RPS-BLAST 2.2.26 [Sep-21-2011]

Database: CDD.v3.10 
           44,354 sequences; 10,937,602 total letters

Searching..................................................done

Query= psy10225
         (207 letters)



>gnl|CDD|212795 cd11861, SH3_DLG-like, Src Homology 3 domain of Disks large
          homolog proteins.  The DLG-like proteins are
          scaffolding proteins that cluster at synapses and are
          also called PSD (postsynaptic density)-95 proteins or
          SAPs (synapse-associated proteins). They play important
          roles in synaptic development and plasticity, cell
          polarity, migration and proliferation. They are members
          of the MAGUK (membrane-associated guanylate kinase)
          protein family, which is characterized by the presence
          of a core of three domains: PDZ, SH3, and guanylate
          kinase (GuK). The GuK domain in MAGUK proteins is
          enzymatically inactive; instead, the domain mediates
          protein-protein interactions and associates
          intramolecularly with the SH3 domain. DLG-like proteins
          contain three PDZ domains and varying N-terminal
          regions. All DLG proteins exist as
          alternatively-spliced isoforms. Vertebrates contain
          four DLG proteins from different genes, called DLG1-4.
          DLG4 and DLG2 are found predominantly at postsynaptic
          sites and they mediate surface ion channel and receptor
          clustering. DLG3 is found axons and some presynaptic
          terminals. DLG1 interacts with AMPA-type glutamate
          receptors and is critical in their maturation and
          delivery to synapses. The SH3 domain of DLG4 binds and
          clusters the kainate subgroup of glutamate receptors
          via two proline-rich sequences in their C-terminal
          tail. It also binds AKAP79/150 (A-kinase anchoring
          protein). SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 61

 Score =  130 bits (328), Expect = 9e-40
 Identities = 43/61 (70%), Positives = 55/61 (90%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSK 78
          + RALFDYDP++D GLPS+GL F +GDILHVTNASDDEWWQARRV P+G+E+ +G++PSK
Sbjct: 1  YVRALFDYDPSRDSGLPSQGLSFKFGDILHVTNASDDEWWQARRVTPNGEEEEVGVIPSK 60

Query: 79 K 79
          +
Sbjct: 61 R 61


>gnl|CDD|212965 cd12032, SH3_DLG2, Src Homology 3 domain of Disks Large homolog
          2.  DLG2, also called postsynaptic density-93 (PSD93)
          or Channel-associated protein of synapse-110 (chapsyn
          110), is a scaffolding protein that clusters at
          synapses and plays an important role in synaptic
          development and plasticity. The DLG2 delta isoform
          binds inwardly rectifying potassium Kir2 channels,
          which determine resting membrane potential in neurons.
          It regulates the spatial and temporal distribution of
          Kir2 channels within neuronal membranes. DLG2 is a
          member of the MAGUK (membrane-associated guanylate
          kinase) protein family, which is characterized by the
          presence of a core of three domains: PDZ, SH3, and
          guanylate kinase (GuK). The GuK domain in MAGUK
          proteins is enzymatically inactive; instead, the domain
          mediates protein-protein interactions and associates
          intramolecularly with the SH3 domain. DLG2 contains
          three PDZ domains. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 74

 Score =  112 bits (281), Expect = 9e-33
 Identities = 46/68 (67%), Positives = 57/68 (83%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSK 78
          + RA+FDY+ +KD GLPS+GL F YGDILHV NASDDEWWQARRV P GD + +G++PSK
Sbjct: 7  YVRAMFDYEKSKDSGLPSQGLSFRYGDILHVINASDDEWWQARRVTPDGDSEEMGVIPSK 66

Query: 79 KRWERKQR 86
          +R ERK+R
Sbjct: 67 RRVERKER 74


>gnl|CDD|212964 cd12031, SH3_DLG1, Src Homology 3 domain of Disks Large homolog
          1.  DLG1, also called synapse-associated protein 97
          (SAP97), is a scaffolding protein that clusters at
          synapses and plays an important role in synaptic
          development and plasticity. DLG1 plays roles in
          regulating cell polarity, proliferation, migration, and
          cycle progression. It interacts with AMPA-type
          glutamate receptors and is critical in their maturation
          and delivery to synapses. It also interacts with
          PKCalpha and promotes wound healing. DLG1 is a member
          of the MAGUK (membrane-associated guanylate kinase)
          protein family, which is characterized by the presence
          of a core of three domains: PDZ, SH3, and guanylate
          kinase (GuK). The GuK domain in MAGUK proteins is
          enzymatically inactive; instead, the domain mediates
          protein-protein interactions and associates
          intramolecularly with the SH3 domain. DLG1 contains
          three PDZ domains. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 67

 Score =  102 bits (255), Expect = 7e-29
 Identities = 43/64 (67%), Positives = 52/64 (81%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSK 78
          + RALFDYD TKD GLPS+GL F +GDILHV NASDDEWWQAR+V   G+ + IG++PSK
Sbjct: 4  YVRALFDYDKTKDSGLPSQGLNFKFGDILHVVNASDDEWWQARQVTADGESEEIGVIPSK 63

Query: 79 KRWE 82
          +R E
Sbjct: 64 RRVE 67


>gnl|CDD|212962 cd12029, SH3_DLG3, Src Homology 3 domain of Disks Large homolog
          3.  DLG3, also called synapse-associated protein 102
          (SAP102), is a scaffolding protein that clusters at
          synapses and plays an important role in synaptic
          development and plasticity. Mutations in DLG3 cause
          midgestational embryonic lethality in mice and may be
          associated with nonsyndromic X-linked mental
          retardation in humans. It interacts with the NEDD4
          (neural precursor cell-expressed developmentally
          downregulated 4) family of ubiquitin ligases and
          promotes apical tight junction formation. DLG3 is a
          member of the MAGUK (membrane-associated guanylate
          kinase) protein family, which is characterized by the
          presence of a core of three domains: PDZ, SH3, and
          guanylate kinase (GuK). The GuK domain in MAGUK
          proteins is enzymatically inactive; instead, the domain
          mediates protein-protein interactions and associates
          intramolecularly with the SH3 domain. DLG3 contains
          three PDZ domains. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 67

 Score = 99.0 bits (246), Expect = 2e-27
 Identities = 44/64 (68%), Positives = 51/64 (79%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSK 78
          + RALFDYD T+D  LPS+GL F YGDILHV NASDDEWWQAR V P G+ + IG++PSK
Sbjct: 4  YVRALFDYDRTRDSCLPSQGLSFSYGDILHVINASDDEWWQARLVTPHGESEQIGVIPSK 63

Query: 79 KRWE 82
          KR E
Sbjct: 64 KRVE 67


>gnl|CDD|212963 cd12030, SH3_DLG4, Src Homology 3 domain of Disks Large homolog
          4.  DLG4, also called postsynaptic density-95 (PSD95)
          or synapse-associated protein 90 (SAP90), is a
          scaffolding protein that clusters at synapses and plays
          an important role in synaptic development and
          plasticity. It is responsible for the membrane
          clustering and retention of many transporters and
          receptors such as potassium channels and PMCA4b, a
          P-type ion transport ATPase, among others. DLG4 is a
          member of the MAGUK (membrane-associated guanylate
          kinase) protein family, which is characterized by the
          presence of a core of three domains: PDZ, SH3, and
          guanylate kinase (GuK). The GuK domain in MAGUK
          proteins is enzymatically inactive; instead, the domain
          mediates protein-protein interactions and associates
          intramolecularly with the SH3 domain. DLG4 contains
          three PDZ domains. The SH3 domain of DLG4 binds and
          clusters the kainate subgroup of glutamate receptors
          via two proline-rich sequences in their C-terminal
          tail. It also binds AKAP79/150 (A-kinase anchoring
          protein). SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 66

 Score = 93.8 bits (233), Expect = 1e-25
 Identities = 36/64 (56%), Positives = 46/64 (71%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSK 78
          + RALFDYD TKD G  S+ L F +GD+LHV +A D+EWWQARRV    + + IG +PSK
Sbjct: 3  YIRALFDYDKTKDCGFLSQALSFRFGDVLHVIDAGDEEWWQARRVHSDSETEEIGFIPSK 62

Query: 79 KRWE 82
          +R E
Sbjct: 63 RRVE 66


>gnl|CDD|212796 cd11862, SH3_MPP, Src Homology 3 domain of Membrane Protein,
          Palmitoylated (or MAGUK p55 subfamily member) proteins.
           The MPP/p55 subfamily of MAGUK (membrane-associated
          guanylate kinase) proteins includes at least eight
          vertebrate members (MPP1-7 and CASK), four Drosophila
          proteins (Stardust, Varicose, CASK and Skiff), and
          other similar proteins; they all contain one each of
          the core of three domains characteristic of MAGUK
          proteins: PDZ, SH3, and guanylate kinase (GuK). In
          addition, most members except for MPP1 contain
          N-terminal L27 domains and some also contain a Hook
          (Protein 4.1 Binding) motif in between the SH3 and GuK
          domains. CASK has an additional calmodulin-dependent
          kinase (CaMK)-like domain at the N-terminus. Members of
          this subfamily are scaffolding proteins that play
          important roles in regulating and establishing cell
          polarity, cell adhesion, and synaptic targeting and
          transmission, among others. The GuK domain in MAGUK
          proteins is enzymatically inactive; instead, the domain
          mediates protein-protein interactions and associates
          intramolecularly with the SH3 domain. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 61

 Score = 81.1 bits (201), Expect = 1e-20
 Identities = 32/63 (50%), Positives = 40/63 (63%), Gaps = 6/63 (9%)

Query: 19 FSRALFDYDPTKDDGLPSR--GLPFHYGDILHVTNASDDEWWQARRVLPSGDEQG-IGIV 75
          F RALFDYDP +D  +P +  GL F  GDIL + N  D  WWQAR+V   GD  G  G++
Sbjct: 1  FVRALFDYDPEEDPLIPCKEAGLSFKKGDILQIVNQDDPNWWQARKV---GDPNGRAGLI 57

Query: 76 PSK 78
          PS+
Sbjct: 58 PSQ 60


>gnl|CDD|212968 cd12035, SH3_MPP1-like, Src Homology 3 domain of Membrane
          Protein, Palmitoylated 1 (or MAGUK p55 subfamily member
          1)-like proteins.  This subfamily includes MPP1, CASK
          (Calcium/calmodulin-dependent Serine protein Kinase),
          Caenorhabditis elegans lin-2, and similar proteins.
          MPP1 and CASK are scaffolding proteins from the MAGUK
          (membrane-associated guanylate kinase) protein family,
          which is characterized by the presence of a core of
          three domains: PDZ, SH3, and guanylate kinase (GuK). In
          addition, they also have the Hook (Protein 4.1 Binding)
          motif in between the SH3 and GuK domains. The GuK
          domain in MAGUK proteins is enzymatically inactive;
          instead, the domain mediates protein-protein
          interactions and associates intramolecularly with the
          SH3 domain. CASK and lin-2 also contain an N-terminal
          calmodulin-dependent kinase (CaMK)-like domain and two
          L27 domains. MPP1 is ubiquitously-expressed and plays
          roles in regulating neutrophil polarity, cell shape,
          hair cell development, and neural development and
          patterning of the retina. CASK is highly expressed in
          the mammalian nervous system and plays roles in
          synaptic protein targeting, neural development, and
          gene expression regulation. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 62

 Score = 70.9 bits (174), Expect = 1e-16
 Identities = 27/61 (44%), Positives = 38/61 (62%), Gaps = 4/61 (6%)

Query: 19 FSRALFDYDPTKDDGLPSR--GLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVP 76
          + RA FDYDP+KDD +P +  G+ F  GDIL + +  D  WWQAR   P   ++  G++P
Sbjct: 1  YVRAQFDYDPSKDDLIPCQQAGIAFKTGDILQIISKDDHNWWQAR--KPGASKEPAGLIP 58

Query: 77 S 77
          S
Sbjct: 59 S 59


>gnl|CDD|212969 cd12036, SH3_MPP5, Src Homology 3 domain of Membrane Protein,
          Palmitoylated 5 (or MAGUK p55 subfamily member 5).
          MPP5, also called PALS1 (Protein associated with Lin7)
          or Nagie oko protein in zebrafish or Stardust in
          Drosophila, is a scaffolding protein which associates
          with Crumbs homolog 1 (CRB1), CRB2, or CRB3 through its
          PDZ domain and with PALS1-associated tight junction
          protein (PATJ) or multi-PDZ domain protein 1 (MUPP1)
          through its L27 domain. The resulting tri-protein
          complexes are core proteins of the Crumb complex, which
          localizes at tight junctions or subapical regions, and
          is involved in the maintenance of apical-basal polarity
          in epithelial cells and the morphogenesis and function
          of photoreceptor cells. MPP5 is critical for the proper
          stratification of the retina and is also expressed in T
          lymphocytes where it is important for TCR-mediated
          activation of NFkB. Drosophila Stardust exists in
          several isoforms, some of which show opposing functions
          in photoreceptor cells, which suggests that the
          relative ratio of different Crumbs complexes regulates
          photoreceptor homeostasis. MPP5 contains two L27
          domains followed by the core of three domains
          characteristic of MAGUK (membrane-associated guanylate
          kinase) proteins: PDZ, SH3, and guanylate kinase (GuK).
          In addition, it also contains the Hook (Protein 4.1
          Binding) motif in between the SH3 and GuK domains. The
          GuK domain in MAGUK proteins is enzymatically inactive;
          instead, the domain mediates protein-protein
          interactions and associates intramolecularly with the
          SH3 domain. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 63

 Score = 69.7 bits (171), Expect = 3e-16
 Identities = 31/63 (49%), Positives = 36/63 (57%), Gaps = 8/63 (12%)

Query: 21 RALFDYDPTKDDGLPSR--GLPFHYGDILHVTNASDDEWWQARRVLPSGDEQG---IGIV 75
          RA FDYDP  D  +P R  GL F  GDILHV +  D  WWQA R    G+E      G++
Sbjct: 3  RAHFDYDPEDDPYIPCRELGLSFQKGDILHVISQEDPNWWQAYR---EGEEDNQSLAGLI 59

Query: 76 PSK 78
          PSK
Sbjct: 60 PSK 62


>gnl|CDD|213013 cd12080, SH3_MPP1, Src Homology 3 domain of Membrane Protein,
          Palmitoylated 1 (or MAGUK p55 subfamily member 1).
          MPP1, also called 55 kDa erythrocyte membrane protein
          (p55), is a ubiquitously-expressed scaffolding protein
          that plays roles in regulating neutrophil polarity,
          cell shape, hair cell development, and neural
          development and patterning of the retina. It was
          originally identified as an erythrocyte protein that
          stabilizes the actin cytoskeleton to the plasma
          membrane by forming a complex with 4.1R protein and
          glycophorin C. MPP1 is one of seven vertebrate homologs
          of the Drosophila Stardust protein, which is required
          in establishing cell polarity, and it contains the
          three domains characteristic of MAGUK
          (membrane-associated guanylate kinase) proteins: PDZ,
          SH3, and guanylate kinase (GuK). In addition, it also
          contains the Hook (Protein 4.1 Binding) motif in
          between the SH3 and GuK domains. The GuK domain in
          MAGUK proteins is enzymatically inactive; instead, the
          domain mediates protein-protein interactions and
          associates intramolecularly with the SH3 domain. SH3
          domains are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 62

 Score = 64.6 bits (157), Expect = 3e-14
 Identities = 26/61 (42%), Positives = 36/61 (59%), Gaps = 4/61 (6%)

Query: 19 FSRALFDYDPTKDDGLPSR--GLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVP 76
          + RA FDYDP KD+ +P +  GL F  GDI+ + N  D  WWQ R  +    E+  G++P
Sbjct: 1  YMRAQFDYDPKKDNLIPCKEAGLKFQTGDIIQIINKDDSNWWQGR--VEGSGEESAGLIP 58

Query: 77 S 77
          S
Sbjct: 59 S 59


>gnl|CDD|212972 cd12039, SH3_MPP3, Src Homology 3 domain of Membrane Protein,
          Palmitoylated 3 (or MAGUK p55 subfamily member 3).
          MPP3 is a scaffolding protein that colocalizes with
          MPP5 and CRB1 at the subdpical region adjacent to
          adherens junctions and may function in photoreceptor
          polarity. It interacts with some nectins and regulates
          their trafficking and processing. Nectins are cell-cell
          adhesion proteins involved in the establishment
          apical-basal polarity at cell adhesion sites. It is one
          of seven vertebrate homologs of the Drosophila Stardust
          protein, which is required in establishing cell
          polarity, and it contains two L27 domains followed by
          the core of three domains characteristic of MAGUK
          (membrane-associated guanylate kinase) proteins: PDZ,
          SH3, and guanylate kinase (GuK). The GuK domain in
          MAGUK proteins is enzymatically inactive; instead, the
          domain mediates protein-protein interactions and
          associates intramolecularly with the SH3 domain. SH3
          domains are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 62

 Score = 61.1 bits (148), Expect = 5e-13
 Identities = 31/64 (48%), Positives = 40/64 (62%), Gaps = 6/64 (9%)

Query: 19 FSRALFDYDPTKDDGLPSR--GLPFHYGDILHVTNASDDEWWQARRVLPSGDEQ-GIGIV 75
          F RALFDY+P +D  +P +  GLPF   DIL V +  D  WWQA+RV   GD     G++
Sbjct: 1  FMRALFDYNPYEDRAIPCQEAGLPFKRRDILEVVSQDDPTWWQAKRV---GDTNLRAGLI 57

Query: 76 PSKK 79
          PSK+
Sbjct: 58 PSKQ 61


>gnl|CDD|213014 cd12081, SH3_CASK, Src Homology 3 domain of
          Calcium/calmodulin-dependent Serine protein Kinase.
          CASK is a scaffolding protein that is highly expressed
          in the mammalian nervous system and plays roles in
          synaptic protein targeting, neural development, and
          gene expression regulation. CASK interacts with many
          different binding partners including parkin, neurexin,
          syndecans, calcium channel proteins, caskin, among
          others, to perform specific functions in different
          subcellular locations. Disruption of the CASK gene in
          mice results in neonatal lethality while mutations in
          the human gene have been associated with X-linked
          mental retardation. Drosophila CASK is associated with
          both pre- and postsynaptic membranes and is crucial in
          synaptic transmission and vesicle cycling. CASK
          contains an N-terminal calmodulin-dependent kinase
          (CaMK)-like domain, two L27 domains, followed by the
          core of three domains characteristic of MAGUK
          (membrane-associated guanylate kinase) proteins: PDZ,
          SH3, and guanylate kinase (GuK). In addition, it also
          contains the Hook (Protein 4.1 Binding) motif in
          between the SH3 and GuK domains. The GuK domain in
          MAGUK proteins is enzymatically inactive; instead, the
          domain mediates protein-protein interactions and
          associates intramolecularly with the SH3 domain. SH3
          domains are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 62

 Score = 59.5 bits (144), Expect = 2e-12
 Identities = 24/61 (39%), Positives = 34/61 (55%), Gaps = 4/61 (6%)

Query: 19 FSRALFDYDPTKDDGLPSR--GLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVP 76
          + RA F+YDP KDD +P +  G+ F  GDIL + +  D  WWQA+           G++P
Sbjct: 1  YVRAQFEYDPLKDDLIPCKQAGIRFRVGDILQIISKDDHNWWQAKLENSKNGTA--GLIP 58

Query: 77 S 77
          S
Sbjct: 59 S 59


>gnl|CDD|212966 cd12033, SH3_MPP7, Src Homology 3 domain of Membrane Protein,
          Palmitoylated 7 (or MAGUK p55 subfamily member 7).
          MPP7 is a scaffolding protein that binds to DLG1 and
          promotes tight junction formation and epithelial cell
          polarity. Mutations in the MPP7 gene may be associated
          with the pathogenesis of diabetes and extreme bone
          mineral density. It is one of seven vertebrate homologs
          of the Drosophila Stardust protein, which is required
          in establishing cell polarity, and it contains two L27
          domains followed by the core of three domains
          characteristic of MAGUK (membrane-associated guanylate
          kinase) proteins: PDZ, SH3, and guanylate kinase (GuK).
          The GuK domain in MAGUK proteins is enzymatically
          inactive; instead, the domain mediates protein-protein
          interactions and associates intramolecularly with the
          SH3 domain. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 61

 Score = 57.0 bits (137), Expect = 2e-11
 Identities = 27/63 (42%), Positives = 37/63 (58%), Gaps = 6/63 (9%)

Query: 19 FSRALFDYDPTKDDGLPSR--GLPFHYGDILHVTNASDDEWWQARRVLPSGDEQ-GIGIV 75
          F +ALFDY+P +D  +P +  GL F  GDIL + +  D  WWQA+     GD     G++
Sbjct: 1  FIKALFDYNPNEDKAIPCKEAGLSFKKGDILQIMSQDDATWWQAKH---EGDANPRAGLI 57

Query: 76 PSK 78
          PSK
Sbjct: 58 PSK 60


>gnl|CDD|212967 cd12034, SH3_MPP4, Src Homology 3 domain of Membrane Protein,
          Palmitoylated 4 (or MAGUK p55 subfamily member 4).
          MPP4, also called Disks Large homolog 6 (DLG6) or
          Amyotrophic lateral sclerosis 2 chromosomal region
          candidate gene 5 protein (ALS2CR5), is a
          retina-specific scaffolding protein that plays a role
          in organizing presynaptic protein complexes in the
          photoreceptor synapse, where it localizes to the plasma
          membrane. It is required in the proper localization of
          calcium ATPases and for maintenance of calcium
          homeostasis. MPP4 is one of seven vertebrate homologs
          of the Drosophila Stardust protein, which is required
          in establishing cell polarity, and it contains two L27
          domains followed by the core of three domains
          characteristic of MAGUK (membrane-associated guanylate
          kinase) proteins: PDZ, SH3, and guanylate kinase (GuK).
          The GuK domain in MAGUK proteins is enzymatically
          inactive; instead, the domain mediates protein-protein
          interactions and associates intramolecularly with the
          SH3 domain. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 61

 Score = 56.4 bits (136), Expect = 3e-11
 Identities = 24/61 (39%), Positives = 35/61 (57%), Gaps = 4/61 (6%)

Query: 19 FSRALFDYDPTKDDGLP--SRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVP 76
          + RA+ DY P +D  +P    GLPF  GDIL + + +D  WWQAR++         G++P
Sbjct: 1  YVRAMVDYWPQQDPSIPCADAGLPFRKGDILQIVDQNDSLWWQARKLSDLA--ACAGLIP 58

Query: 77 S 77
          S
Sbjct: 59 S 59


>gnl|CDD|214620 smart00326, SH3, Src homology 3 domains.  Src homology 3 (SH3)
          domains bind to target proteins through sequences
          containing proline and hydrophobic amino acids.
          Pro-containing polypeptides may bind to SH3 domains in
          2 different binding orientations.
          Length = 56

 Score = 54.1 bits (131), Expect = 2e-10
 Identities = 22/57 (38%), Positives = 27/57 (47%), Gaps = 10/57 (17%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          RAL+DY     D L      F  GDI+ V   SDD WW+ R     G  +  G+ PS
Sbjct: 6  RALYDYTAQDPDELS-----FKKGDIITVLEKSDDGWWKGRL----GRGK-EGLFPS 52


>gnl|CDD|212971 cd12038, SH3_MPP6, Src Homology 3 domain of Membrane Protein,
          Palmitoylated 6 (or MAGUK p55 subfamily member 6).
          MPP6, also called Veli-associated MAGUK 1 (VAM-1) or
          PALS2, is a scaffolding protein that binds to Veli-1, a
          homolog of Caenorhabditis Lin-7. It is one of seven
          vertebrate homologs of the Drosophila Stardust protein,
          which is required in establishing cell polarity, and it
          contains two L27 domains followed by the core of three
          domains characteristic of MAGUK (membrane-associated
          guanylate kinase) proteins: PDZ, SH3, and guanylate
          kinase (GuK). In addition, it also contains the Hook
          (Protein 4.1 Binding) motif in between the SH3 and GuK
          domains. The GuK domain in MAGUK proteins is
          enzymatically inactive; instead, the domain mediates
          protein-protein interactions and associates
          intramolecularly with the SH3 domain. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 61

 Score = 53.5 bits (128), Expect = 4e-10
 Identities = 24/62 (38%), Positives = 34/62 (54%), Gaps = 5/62 (8%)

Query: 19 FSRALFDYDPTKDDGLPSR--GLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVP 76
          F +  FDY+P  D+ +P +  GL F  G+IL + N  D  WWQA  V   G     G++P
Sbjct: 1  FVKCHFDYNPYNDNLIPCKEAGLKFSKGEILQIVNREDPNWWQASHVKEGGSA---GLIP 57

Query: 77 SK 78
          S+
Sbjct: 58 SQ 59


>gnl|CDD|212970 cd12037, SH3_MPP2, Src Homology 3 domain of Membrane Protein,
          Palmitoylated 2 (or MAGUK p55 subfamily member 2).
          MPP2 is a scaffolding protein that interacts with the
          non-receptor tyrosine kinase c-Src in epithelial cells
          to negatively regulate its activity and morphological
          function. It is one of seven vertebrate homologs of the
          Drosophila Stardust protein, which is required in
          establishing cell polarity, and it contains two L27
          domains followed by the core of three domains
          characteristic of MAGUK (membrane-associated guanylate
          kinase) proteins: PDZ, SH3, and guanylate kinase (GuK).
          In addition, it also contains the Hook (Protein 4.1
          Binding) motif in between the SH3 and GuK domains. The
          GuK domain in MAGUK proteins is enzymatically inactive;
          instead, the domain mediates protein-protein
          interactions and associates intramolecularly with the
          SH3 domain. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 59

 Score = 53.0 bits (127), Expect = 5e-10
 Identities = 26/63 (41%), Positives = 35/63 (55%), Gaps = 8/63 (12%)

Query: 19 FSRALFDYDPTKDDGLPSR--GLPFHYGDILHVTNASDDEWWQARRVLPSGDEQG-IGIV 75
          F +  FDYDP+ D  +P +  GL F  GD+L + N  D  WWQA  V     E G  G++
Sbjct: 1  FVKCHFDYDPSSDSLIPCKEAGLKFRAGDLLQIVNQEDPNWWQACHV-----EGGSAGLI 55

Query: 76 PSK 78
          PS+
Sbjct: 56 PSQ 58


>gnl|CDD|212690 cd00174, SH3, Src Homology 3 domain superfamily.  Src Homology 3
          (SH3) domains are protein interaction domains that bind
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. Thus, they
          are referred to as proline-recognition domains (PRDs).
          SH3 domains are less selective and show more diverse
          specificity compared to other PRDs. They have been
          shown to bind peptide sequences that lack the PxxP
          motif; examples include the PxxDY motif of Eps8 and the
          RKxxYxxY sequence in SKAP55. SH3 domain containing
          proteins play versatile and diverse roles in the cell,
          including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies, among others. Many members of this
          superfamily are adaptor proteins that associate with a
          number of protein partners, facilitating complex
          formation and signal transduction.
          Length = 51

 Score = 52.9 bits (128), Expect = 5e-10
 Identities = 19/57 (33%), Positives = 26/57 (45%), Gaps = 10/57 (17%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          RAL+DY+   DD L      F  GDI+ V    DD WW+        +    G+ P+
Sbjct: 3  RALYDYEAQDDDELS-----FKKGDIITVLEKDDDGWWEGEL-----NGGREGLFPA 49


>gnl|CDD|212707 cd11773, SH3_Sla1p_1, First Src Homology 3 domain of the fungal
          endocytic adaptor protein Sla1p.  Sla1p facilitates
          endocytosis by playing a role as an adaptor protein in
          coupling components of the actin cytoskeleton to the
          endocytic machinery. It interacts with Abp1p, Las17p
          and Pan1p, which are activator proteins of
          actin-related protein 2/3 (Arp2/3). Sla1p contains
          multiple domains including three SH3 domains, a SAM
          (sterile alpha motif) domain, and a Sla1 homology
          domain 1 (SHD1), which binds to the NPFXD motif that is
          found in many integral membrane proteins such as the
          Golgi-localized Arf-binding protein Lsb5p and the
          P4-ATPases, Drs2p and Dnf1p. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 57

 Score = 50.5 bits (121), Expect = 4e-09
 Identities = 21/58 (36%), Positives = 36/58 (62%), Gaps = 6/58 (10%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQAR-RVLPSGDEQGIGIVPS 77
          +AL+DY+P  +D L          DIL++   SDD+WW+ + +V  S D++ +G+VP+
Sbjct: 3  KALYDYEPQTEDELT-----IQEDDILYLLEKSDDDWWKVKLKVNSSDDDEPVGLVPA 55


>gnl|CDD|215659 pfam00018, SH3_1, SH3 domain.  SH3 (Src homology 3) domains are
          often indicative of a protein involved in signal
          transduction related to cytoskeletal organisation.
          First described in the Src cytoplasmic tyrosine kinase.
          The structure is a partly opened beta barrel.
          Length = 47

 Score = 49.1 bits (118), Expect = 1e-08
 Identities = 20/57 (35%), Positives = 26/57 (45%), Gaps = 10/57 (17%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
           AL+DY   + D L      F  GDI+ V   SDD WW+ R           G++PS
Sbjct: 1  VALYDYTAREPDELS-----FKKGDIIIVLEKSDDGWWKGRL-----KGGKEGLIPS 47


>gnl|CDD|212779 cd11845, SH3_Src_like, Src homology 3 domain of Src kinase-like
          Protein Tyrosine Kinases.  Src subfamily members
          include Src, Lck, Hck, Blk, Lyn, Fgr, Fyn, Yrk, Yes,
          and Brk. Src (or c-Src) proteins are cytoplasmic (or
          non-receptor) PTKs which are anchored to the plasma
          membrane. They contain an N-terminal SH4 domain with a
          myristoylation site, followed by SH3 and SH2 domains, a
          tyr kinase domain, and a regulatory C-terminal region
          containing a conserved tyr. They are activated by
          autophosphorylation at the tyr kinase domain, but are
          negatively regulated by phosphorylation at the
          C-terminal tyr by Csk (C-terminal Src Kinase). However,
          Brk lacks the N-terminal myristoylation sites. Src
          proteins are involved in signaling pathways that
          regulate cytokine and growth factor responses,
          cytoskeleton dynamics, cell proliferation, survival,
          and differentiation. They were identified as the first
          proto-oncogene products, and they regulate cell
          adhesion, invasion, and motility in cancer cells, and
          tumor vasculature, contributing to cancer progression
          and metastasis. Src kinases are overexpressed in a
          variety of human cancers, making them attractive
          targets for therapy. They are also implicated in acute
          inflammatory responses and osteoclast function. Src,
          Fyn, Yes, and Yrk are widely expressed, while Blk, Lck,
          Hck, Fgr, Lyn, and Brk show a limited expression
          pattern. This subfamily also includes Drosophila
          Src42A, Src oncogene at 42A (also known as Dsrc41)
          which accumulates at sites of cell-cell or cell-matrix
          adhesion, and participates in Drosphila development and
          wound healing. It has been shown to promote tube
          elongation in the tracheal system, is essential for
          proper cell-cell matching during dorsal closure, and
          regulates cell-cell contacts in developing Drosophila
          eyes. The SH3 domain of Src kinases contributes to
          substrate recruitment by binding adaptor
          proteins/substrates, and regulation of kinase activity
          through an intramolecular interaction. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 52

 Score = 47.2 bits (113), Expect = 7e-08
 Identities = 24/58 (41%), Positives = 31/58 (53%), Gaps = 11/58 (18%)

Query: 21 RALFDYDP-TKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
           AL+DY+  T DD      L F  GD L + + SD +WW AR  L +G E   G +PS
Sbjct: 3  VALYDYEARTDDD------LSFKKGDRLQILDDSDGDWWLARH-LSTGKE---GYIPS 50


>gnl|CDD|212706 cd11772, SH3_OSTF1, Src Homology 3 domain of metazoan osteoclast
          stimulating factor 1.  OSTF1, also named OSF or SH3P2,
          is a signaling protein containing SH3 and
          ankyrin-repeat domains. It acts through a Src-related
          pathway to enhance the formation of osteoclasts and
          bone resorption. It also acts as a negative regulator
          of cell motility. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 53

 Score = 44.6 bits (106), Expect = 7e-07
 Identities = 20/57 (35%), Positives = 31/57 (54%), Gaps = 11/57 (19%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          RAL+DY+    D L      F  GD+L++++ SD  WW+A      G +   G++PS
Sbjct: 3  RALYDYEAQHPDELS-----FEEGDLLYISDKSDPNWWKAT----CGGKT--GLIPS 48


>gnl|CDD|212789 cd11855, SH3_Sho1p, Src homology 3 domain of High osmolarity
          signaling protein Sho1p.  Sho1p (or Sho1), also called
          SSU81 (Suppressor of SUA8-1 mutation), is a yeast
          membrane protein that regulates adaptation to high salt
          conditions by activating the HOG (high-osmolarity
          glycerol) pathway. High salt concentrations lead to the
          localization to the membrane of the MAPKK Pbs2, which
          is then activated by the MAPKK Ste11 and in turn,
          activates the MAPK Hog1. Pbs2 is localized to the
          membrane though the interaction of its PxxP motif with
          the SH3 domain of Sho1p. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 55

 Score = 42.8 bits (101), Expect = 3e-06
 Identities = 24/57 (42%), Positives = 33/57 (57%), Gaps = 9/57 (15%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          RAL+ YD + DD      L F  G+IL V++ S  +WWQAR+   +G+    GI PS
Sbjct: 3  RALYPYDASPDD---PNELSFEKGEILEVSDTS-GKWWQARK--SNGE---TGICPS 50


>gnl|CDD|212741 cd11807, SH3_ASPP, Src homology 3 domain of Apoptosis Stimulating
          of p53 proteins (ASPP).  The ASPP family of proteins
          bind to important regulators of apoptosis (p53, Bcl-2,
          and RelA) and cell growth (APCL, PP1). They share
          similarity at their C-termini, where they harbor a
          proline-rich region, four ankyrin (ANK) repeats, and an
          SH3 domain. Vertebrates contain three members of the
          family: ASPP1, ASPP2, and iASPP. ASPP1 and ASPP2
          activate the apoptotic function of the p53 family of
          tumor suppressors (p53, p63, and p73), while iASPP is
          an oncoprotein that specifically inhibits p53-induced
          apoptosis. The expression of ASPP proteins is altered
          in tumors; ASPP1 and ASPP2 are downregulated whereas
          iASPP is upregulated is some cancer types. ASPP
          proteins also bind and regulate protein phosphatase 1
          (PP1), and this binding is competitive with p53
          binding. The SH3 domain and the ANK repeats of ASPP
          contribute to the p53 binding site; they bind to the
          DNA binding domain of p53. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 57

 Score = 41.6 bits (98), Expect = 9e-06
 Identities = 21/53 (39%), Positives = 24/53 (45%), Gaps = 12/53 (22%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDD---EWWQARRVLPSGDEQG 71
          ALFDY+    D      L F  GD L V    DD   EWW AR      D++G
Sbjct: 5  ALFDYEAENGD-----ELSFREGDELTVLRKGDDDETEWWWAR----LNDKEG 48


>gnl|CDD|212882 cd11949, SH3_GRB2_C, C-terminal Src homology 3 domain of Growth
          factor receptor-bound protein 2.  GRB2 is a critical
          signaling molecule that regulates the Ras pathway by
          linking tyrosine kinases to the Ras guanine nucleotide
          releasing protein Sos (son of sevenless), which
          converts Ras to the active GTP-bound state. It is
          ubiquitously expressed in all tissues throughout
          development and is important in cell cycle progression,
          motility, morphogenesis, and angiogenesis. In
          lymphocytes, GRB2 is associated with antigen receptor
          signaling components. GRB2 contains an N-terminal SH3
          domain, a central SH2 domain, and a C-terminal SH3
          domain. The C-terminal SH3 domain of GRB2 binds to Gab2
          (Grb2-associated binder 2) through epitopes containing
          RxxK motifs, as well as to the proline-rich C-terminus
          of FGRF2. SH3 domains are protein interaction domains
          that typically bind to proline-rich ligands with
          moderate affinity and selectivity, preferentially to
          PxxP motifs. They play versatile and diverse roles in
          the cell including the regulation of enzymes, changing
          the subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 53

 Score = 41.0 bits (96), Expect = 1e-05
 Identities = 16/41 (39%), Positives = 23/41 (56%), Gaps = 5/41 (12%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQ 59
          + +ALFD+DP +D  L      F  GD + V + SD  WW+
Sbjct: 1  YVQALFDFDPQEDGELG-----FRRGDFIEVMDNSDPNWWK 36


>gnl|CDD|219499 pfam07653, SH3_2, Variant SH3 domain.  SH3 (Src homology 3)
          domains are often indicative of a protein involved in
          signal transduction related to cytoskeletal
          organisation. First described in the Src cytoplasmic
          tyrosine kinase. The structure is a partly opened beta
          barrel.
          Length = 53

 Score = 40.9 bits (97), Expect = 1e-05
 Identities = 17/60 (28%), Positives = 24/60 (40%), Gaps = 11/60 (18%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSKKR 80
          R +FDY  T         L    GD++ V +  D+ WW+  R          G+VPS   
Sbjct: 3  RVIFDYVATDP-----NELSLKKGDVVKVLDKDDNGWWEGER------GGRRGLVPSSYV 51


>gnl|CDD|212692 cd11758, SH3_CRK_N, N-terminal Src Homology 3 domain of Ct10
          Regulator of Kinase adaptor proteins.  CRK adaptor
          proteins consists of SH2 and SH3 domains, which bind
          tyrosine-phosphorylated peptides and proline-rich
          motifs, respectively. They function downstream of
          protein tyrosine kinases in many signaling pathways
          started by various extracellular signals, including
          growth and differentiation factors. Cellular CRK
          (c-CRK) contains a single SH2 domain, followed by
          N-terminal and C-terminal SH3 domains. It is involved
          in the regulation of many cellular processes including
          cell growth, motility, adhesion, and apoptosis. CRK has
          been implicated in the malignancy of various human
          cancers. The N-terminal SH3 domain of CRK binds a
          number of target proteins including DOCK180, C3G, SOS,
          and cABL. The CRK family includes two alternatively
          spliced protein forms, CRKI and CRKII, that are
          expressed by the CRK gene, and the CRK-like (CRKL)
          protein, which is expressed by a distinct gene (CRKL).
          SH3 domains are protein interaction domains that bind
          to proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 55

 Score = 40.0 bits (94), Expect = 3e-05
 Identities = 20/57 (35%), Positives = 30/57 (52%), Gaps = 12/57 (21%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQG-IGIVP 76
          RALFD+    D+ LP     F  G+IL V    +++WW AR      + +G  G++P
Sbjct: 4  RALFDFPGNDDEDLP-----FKKGEILTVIRKPEEQWWNAR------NSEGKTGMIP 49


>gnl|CDD|212739 cd11805, SH3_GRB2_like_C, C-terminal Src homology 3 domain of
          Growth factor receptor-bound protein 2 (GRB2) and
          related proteins.  This family includes the adaptor
          protein GRB2 and related proteins including Drosophila
          melanogaster Downstream of receptor kinase (DRK),
          Caenorhabditis elegans Sex muscle abnormal protein 5
          (Sem-5), GRB2-related adaptor protein (GRAP), GRAP2,
          and similar proteins. Family members contain an
          N-terminal SH3 domain, a central SH2 domain, and a
          C-terminal SH3 domain. GRB2/Sem-5/DRK is a critical
          signaling molecule that regulates the Ras pathway by
          linking tyrosine kinases to the Ras guanine nucleotide
          releasing protein Sos (son of sevenless), which
          converts Ras to the active GTP-bound state. GRAP2 plays
          an important role in T cell receptor (TCR) signaling by
          promoting the formation of the SLP-76:LAT complex,
          which couples the TCR to the Ras pathway. GRAP acts as
          a negative regulator of T cell receptor (TCR)-induced
          lymphocyte proliferation by downregulating the
          signaling to the Ras/ERK pathway. The C-terminal SH3
          domains (SH3c) of GRB2 and GRAP2 have been shown to
          bind to classical PxxP motif ligands, as well as to
          non-classical motifs. GRB2 SH3c binds Gab2
          (Grb2-associated binder 2) through epitopes containing
          RxxK motifs, while the SH3c of GRAP2 binds to the
          phosphatase-like protein HD-PTP via a RxxxxK motif. SH3
          domains are protein interaction domains that typically
          bind to proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 53

 Score = 39.9 bits (94), Expect = 4e-05
 Identities = 14/43 (32%), Positives = 24/43 (55%), Gaps = 5/43 (11%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQAR 61
            +AL+D++P +   L      F  GDI+ V ++SD +WW+  
Sbjct: 1  RVQALYDFNPQEPGELE-----FRRGDIITVLDSSDPDWWKGE 38


>gnl|CDD|212939 cd12006, SH3_Fyn_Yrk, Src homology 3 domain of Fyn and Yrk
          Protein Tyrosine Kinases.  Fyn and Yrk (Yes-related
          kinase) are members of the Src subfamily of proteins,
          which are cytoplasmic (or non-receptor) PTKs. Fyn,
          together with Lck, plays a critical role in T-cell
          signal transduction by phosphorylating ITAM
          (immunoreceptor tyr activation motif) sequences on
          T-cell receptors, ultimately leading to the
          proliferation and differentiation of T-cells. In
          addition, Fyn is involved in the myelination of
          neurons, and is implicated in Alzheimer's and
          Parkinson's diseases. Yrk has been detected only in
          chickens. It is primarily found in neuronal and
          epithelial cells and in macrophages. It may play a role
          in inflammation and in response to injury. Src kinases
          contain an N-terminal SH4 domain with a myristoylation
          site, followed by SH3 and SH2 domains, a tyr kinase
          domain, and a regulatory C-terminal region containing a
          conserved tyr. They are activated by
          autophosphorylation at the tyr kinase domain, but are
          negatively regulated by phosphorylation at the
          C-terminal tyr by Csk (C-terminal Src Kinase). The SH3
          domain of Src kinases contributes to substrate
          recruitment by binding adaptor proteins/substrates, and
          regulation of kinase activity through an intramolecular
          interaction. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 56

 Score = 39.6 bits (92), Expect = 5e-05
 Identities = 22/57 (38%), Positives = 33/57 (57%), Gaps = 11/57 (19%)

Query: 22 ALFDYDP-TKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          AL+DY+  T+DD      L FH G+   + N+S+ +WW+AR  L +G     G +PS
Sbjct: 5  ALYDYEARTEDD------LSFHKGEKFQILNSSEGDWWEARS-LTTG---ETGYIPS 51


>gnl|CDD|212754 cd11820, SH3_STAM, Src homology 3 domain of Signal Transducing
          Adaptor Molecules.  STAMs were discovered as proteins
          that are highly phosphorylated following cytokine and
          growth factor stimulation. They function in cytokine
          signaling and surface receptor degradation, as well as
          regulate Golgi morphology. They associate with many
          proteins including Jak2 and Jak3 tyrosine kinases, Hrs,
          AMSH, and UBPY. STAM adaptor proteins contain VHS
          (Vps27, Hrs, STAM homology), ubiquitin interacting
          (UIM), and SH3 domains. There are two vertebrate STAMs,
          STAM1 and STAM2, which may be functionally redundant;
          vertebrate STAMs contain ITAM motifs. They are part of
          the endosomal sorting complex required for transport
          (ESCRT-0). STAM2 deficiency in mice did not cause any
          obvious abnormality, while STAM1 deficiency resulted in
          growth retardation. Loss of both STAM1 and STAM2 in
          mice proved lethal, indicating that STAMs are important
          for embryonic development. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 54

 Score = 39.4 bits (92), Expect = 6e-05
 Identities = 17/57 (29%), Positives = 30/57 (52%), Gaps = 11/57 (19%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          RAL+D++  +D+ L      F  G+I+ V + SD  WW+        + +G G+ P+
Sbjct: 4  RALYDFEAAEDNELT-----FKAGEIITVLDDSDPNWWKGS------NHRGEGLFPA 49


>gnl|CDD|212884 cd11951, SH3_GRAP_C, C-terminal Src homology 3 domain of
          GRB2-related adaptor protein.  GRAP is a GRB-2 like
          adaptor protein that is highly expressed in lymphoid
          tissues. It acts as a negative regulator of T cell
          receptor (TCR)-induced lymphocyte proliferation by
          downregulating the signaling to the Ras/ERK pathway. It
          has been identified as a regulator of TGFbeta signaling
          in diabetic kidney tubules and may have a role in the
          pathogenesis of the disease. GRAP contains an
          N-terminal SH3 domain, a central SH2 domain, and a
          C-terminal SH3 domain. The C-terminal SH3 domains
          (SH3c) of the related proteins, GRB2 and GRAP2, have
          been shown to bind to classical PxxP motif ligands, as
          well as to non-classical motifs. GRB2 SH3c binds Gab2
          (Grb2-associated binder 2) through epitopes containing
          RxxK motifs, while the SH3c of GRAP2 binds to the
          phosphatase-like protein HD-PTP via a RxxxxK motif. SH3
          domains are protein interaction domains that typically
          bind to proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 53

 Score = 38.6 bits (90), Expect = 8e-05
 Identities = 13/43 (30%), Positives = 19/43 (44%), Gaps = 5/43 (11%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQAR 61
          F +A +D+            L F  GDI+ V +  D  WW+ R
Sbjct: 1  FVQAQYDFSAED-----PSQLSFRRGDIIEVLDCPDPNWWRGR 38


>gnl|CDD|212760 cd11826, SH3_Abi, Src homology 3 domain of Abl Interactor
          proteins.  Abl interactor (Abi) proteins are adaptor
          proteins serving as binding partners and substrates of
          Abl tyrosine kinases. They are involved in regulating
          actin cytoskeletal reorganization and play important
          roles in membrane-ruffling, endocytosis, cell motility,
          and cell migration. They localize to sites of actin
          polymerization in epithelial adherens junction and
          immune synapses, as well as to the leading edge of
          lamellipodia. Vertebrates contain two Abi proteins,
          Abi1 and Abi2. Abi1 displays a wide expression pattern
          while Abi2 is highly expressed in the eye and brain.
          Abi proteins contain a homeobox homology domain, a
          proline-rich region, and a SH3 domain. The SH3 domain
          of Abi binds to a PxxP motif in Abl. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 52

 Score = 38.5 bits (90), Expect = 9e-05
 Identities = 17/39 (43%), Positives = 23/39 (58%), Gaps = 5/39 (12%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQ 59
           AL+DY   KDD L      F  GDI++VT  +DD W++
Sbjct: 3  VALYDYTADKDDELS-----FQEGDIIYVTKKNDDGWYE 36


>gnl|CDD|212797 cd11863, SH3_CACNB, Src Homology 3 domain of Voltage-dependent
          L-type calcium channel subunit beta.  Voltage-dependent
          calcium channels (Ca(V)s) are multi-protein complexes
          that regulate the entry of calcium into cells. They
          impact muscle contraction, neuronal migration, hormone
          and neurotransmitter release, and the activation of
          calcium-dependent signaling pathways. They are composed
          of four subunits: alpha1, alpha2delta, beta, and gamma.
          The beta subunit is a soluble and intracellular protein
          that interacts with the transmembrane alpha1 subunit.
          It facilitates the trafficking and proper localization
          of the alpha1 subunit to the cellular plasma membrane.
          Vertebrates contain four different beta subunits from
          distinct genes (beta1-4); each exists as multiple
          splice variants. All are expressed in the brain while
          other tissues show more specific expression patterns.
          The beta subunits show similarity to MAGUK
          (membrane-associated guanylate kinase) proteins in that
          they contain SH3 and inactive guanylate kinase (GuK)
          domains; however, they do not appear to contain a PDZ
          domain. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 62

 Score = 38.4 bits (90), Expect = 1e-04
 Identities = 20/60 (33%), Positives = 27/60 (45%), Gaps = 5/60 (8%)

Query: 20 SRALFDYDPTKDDGLPSRG--LPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
           R    YD + DD  P  G  + F   D LH+    +++WW  R V    D   IG +PS
Sbjct: 3  VRTNVGYDGSLDDDSPVPGYAVSFEAKDFLHIKEKYNNDWWIGRLVKEGCD---IGFIPS 59


>gnl|CDD|212896 cd11963, SH3_STAM2, Src homology 3 domain of Signal Transducing
          Adaptor Molecule 2.  STAM2, also called EAST (Epidermal
          growth factor receptor-associated protein with SH3 and
          TAM domain) or Hbp (Hrs binding protein), is part of
          the endosomal sorting complex required for transport
          (ESCRT-0). It plays a role in sorting mono-ubiquinated
          endosomal cargo for trafficking to the lysosome for
          degradation. It is also involved in the regulation of
          exocytosis. STAMs were discovered as proteins that are
          highly phosphorylated following cytokine and growth
          factor stimulation. They function in cytokine signaling
          and surface receptor degradation, as well as regulate
          Golgi morphology. They associate with many proteins
          including Jak2 and Jak3 tyrosine kinases, Hrs, AMSH,
          and UBPY. STAM adaptor proteins contain VHS (Vps27,
          Hrs, STAM homology), ubiquitin interacting (UIM), and
          SH3 domains. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 57

 Score = 38.1 bits (88), Expect = 2e-04
 Identities = 18/57 (31%), Positives = 32/57 (56%), Gaps = 11/57 (19%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          RAL+D++  +D+ L      F +G+I+ V + SD  WW+        + +G+G+ PS
Sbjct: 5  RALYDFEAVEDNELT-----FKHGEIIIVLDDSDANWWKGE------NHRGVGLFPS 50


>gnl|CDD|212762 cd11828, SH3_ARHGEF9_like, Src homology 3 domain of ARHGEF9-like
          Rho guanine nucleotide exchange factors.  Members of
          this family contain a SH3 domain followed by RhoGEF
          (also called Dbl-homologous or DH) and Pleckstrin
          Homology (PH) domains. They include the Rho guanine
          nucleotide exchange factors ARHGEF9, ASEF (also called
          ARHGEF4), ASEF2, and similar proteins. GEFs activate
          small GTPases by exchanging bound GDP for free GTP.
          ARHGEF9 specifically activates Cdc42, while both ASEF
          and ASEF2 can activate Rac1 and Cdc42. ARHGEF9 is
          highly expressed in the brain and it interacts with
          gephyrin, a postsynaptic protein associated with GABA
          and glycine receptors. ASEF plays a role in
          angiogenesis and cell migration. ASEF2 is important in
          cell migration and adhesion dynamics. ASEF exists in an
          autoinhibited form and is activated upon binding of the
          tumor suppressor APC (adenomatous polyposis coli),
          leading to the activation of Rac1 or Cdc42. In its
          autoinhibited form, the SH3 domain of ASEF forms an
          extensive interface with the DH and PH domains,
          blocking the Rac binding site. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 53

 Score = 37.7 bits (88), Expect = 2e-04
 Identities = 17/53 (32%), Positives = 25/53 (47%), Gaps = 9/53 (16%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQG 71
           + AL+D+  T D       L F  GD++ V + SD +WW         DE+G
Sbjct: 1  LAEALWDHV-TMDP----EELGFKAGDVIEVLDMSDKDWWWGSI----RDEEG 44


>gnl|CDD|212737 cd11803, SH3_Endophilin_A, Src homology 3 domain of Endophilin-A.
           Endophilins play roles in synaptic vesicle formation,
          virus budding, mitochondrial morphology maintenance,
          receptor-mediated endocytosis inhibition, and endosomal
          sorting. They are classified into two types, A and B.
          Vertebrates contain three endophilin-A isoforms (A1,
          A2, and A3). Endophilin-A proteins are enriched in the
          brain and play multiple roles in receptor-mediated
          endocytosis. They tubulate membranes and regulate
          calcium influx into neurons to trigger the activation
          of the endocytic machinery. They are also involved in
          the sorting of plasma membrane proteins, actin filament
          assembly, and the uncoating of clathrin-coated vesicles
          for fusion with endosomes. Endophilins contain an
          N-terminal N-BAR domain (BAR domain with an additional
          N-terminal amphipathic helix), followed by a variable
          region containing proline clusters, and a C-terminal
          SH3 domain. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 55

 Score = 37.6 bits (88), Expect = 2e-04
 Identities = 15/41 (36%), Positives = 26/41 (63%), Gaps = 5/41 (12%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQAR 61
          RAL+D++P +++G     L F  GDI+ +TN  D+ W++  
Sbjct: 4  RALYDFEP-ENEG----ELGFKEGDIITLTNQIDENWYEGM 39


>gnl|CDD|212897 cd11964, SH3_STAM1, Src homology 3 domain of Signal Transducing
          Adaptor Molecule 1.  STAM1 is part of the endosomal
          sorting complex required for transport (ESCRT-0) and is
          involved in sorting ubiquitinated cargo proteins from
          the endosome. It may also be involved in the regulation
          of IL2 and GM-CSF mediated signaling, and has been
          implicated in neural cell survival. STAMs were
          discovered as proteins that are highly phosphorylated
          following cytokine and growth factor stimulation. They
          function in cytokine signaling and surface receptor
          degradation, as well as regulate Golgi morphology. They
          associate with many proteins including Jak2 and Jak3
          tyrosine kinases, Hrs, AMSH, and UBPY. STAM adaptor
          proteins contain VHS (Vps27, Hrs, STAM homology),
          ubiquitin interacting (UIM), and SH3 domains. SH3
          domains are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 55

 Score = 36.9 bits (85), Expect = 4e-04
 Identities = 18/57 (31%), Positives = 29/57 (50%), Gaps = 11/57 (19%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          RA++D++  +D+ L      F  GDI+ + + SD  WW+          QG G+ PS
Sbjct: 4  RAIYDFEAAEDNELT-----FKAGDIITILDDSDPNWWKGE------TPQGTGLFPS 49


>gnl|CDD|212883 cd11950, SH3_GRAP2_C, C-terminal Src homology 3 domain of
          GRB2-related adaptor protein 2.  GRAP2 is also called
          GADS (GRB2-related adapter downstream of Shc), GrpL,
          GRB2L, Mona, or GRID (Grb2-related protein with insert
          domain). It is expressed specifically in the
          hematopoietic system. It plays an important role in T
          cell receptor (TCR) signaling by promoting the
          formation of the SLP-76:LAT complex, which couples the
          TCR to the Ras pathway. It also has roles in
          antigen-receptor and tyrosine kinase mediated
          signaling. GRAP2 is unique from other GRB2-like adaptor
          proteins in that it can be regulated by caspase
          cleavage. It contains an N-terminal SH3 domain, a
          central SH2 domain, and a C-terminal SH3 domain. The
          C-terminal SH3 domain of GRAP2 binds to different
          motifs found in substrate peptides including the
          typical PxxP motif in hematopoietic progenitor kinase 1
          (HPK1), the RxxK motif in SLP-76 and HPK1, and the
          RxxxxK motif in phosphatase-like protein HD-PTP. SH3
          domains are protein interaction domains that typically
          bind to proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 53

 Score = 36.7 bits (85), Expect = 5e-04
 Identities = 15/41 (36%), Positives = 26/41 (63%), Gaps = 5/41 (12%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQAR 61
          RAL+D++  +DD L      F+ GD++ V ++S+  WW+ R
Sbjct: 3  RALYDFEALEDDELG-----FNSGDVIEVLDSSNPSWWKGR 38


>gnl|CDD|212942 cd12009, SH3_Blk, Src homology 3 domain of Blk Protein Tyrosine
          Kinase.  Blk is a member of the Src subfamily of
          proteins, which are cytoplasmic (or non-receptor) PTKs.
          It is expressed specifically in B-cells and is involved
          in pre-BCR (B-cell receptor) signaling. Src kinases
          contain an N-terminal SH4 domain with a myristoylation
          site, followed by SH3 and SH2 domains, a tyr kinase
          domain, and a regulatory C-terminal region containing a
          conserved tyr. They are activated by
          autophosphorylation at the tyr kinase domain, but are
          negatively regulated by phosphorylation at the
          C-terminal tyr by Csk (C-terminal Src Kinase). The SH3
          domain of Src kinases contributes to substrate
          recruitment by binding adaptor proteins/substrates, and
          regulation of kinase activity through an intramolecular
          interaction. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 54

 Score = 36.3 bits (84), Expect = 6e-04
 Identities = 20/56 (35%), Positives = 28/56 (50%), Gaps = 10/56 (17%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          A +D+ P+ +     R L    G+ L V   SD EWW A+  L +G E   G +PS
Sbjct: 4  AQYDFVPSNE-----RDLQLKKGEKLQVL-KSDGEWWLAKS-LTTGKE---GYIPS 49


>gnl|CDD|212886 cd11953, SH3_ASPP2, Src Homology 3 (SH3) domain of Apoptosis
          Stimulating of p53 protein 2.  ASPP2 is the full length
          form of the previously-identified tumor supressor,
          p53-binding protein 2 (p53BP2). ASPP2 activates the
          apoptotic function of the p53 family of tumor
          suppressors (p53, p63, and p73). It plays a central
          role in regulating apoptosis and cell growth;
          ASPP2-deficient mice show postnatal death.
          Downregulated expression of ASPP2 is frequently found
          in breast tumors, lung cancer, and diffuse large B-cell
          lymphoma where it is correlated with a poor clinical
          outcome. ASPP2 contains a proline-rich region, four
          ankyrin (ANK) repeats, and an SH3 domain at its
          C-terminal half. The SH3 domain and the ANK repeats of
          ASPP2 contribute to the p53 binding site; they bind to
          the DNA binding domain of p53. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 57

 Score = 36.1 bits (83), Expect = 0.001
 Identities = 17/43 (39%), Positives = 21/43 (48%), Gaps = 8/43 (18%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGD---ILHVTNASDDEWWQAR 61
          AL+DY+   DD      L F  GD   IL   +  + EWW AR
Sbjct: 5  ALWDYEGESDD-----ELSFKEGDCMTILRREDEDETEWWWAR 42


>gnl|CDD|212811 cd11878, SH3_Bem1p_1, First Src Homology 3 domain of Bud
          emergence protein 1 and similar domains.  Members of
          this subfamily bear similarity to Saccharomyces
          cerevisiae Bem1p, containing two Src Homology 3 (SH3)
          domains at the N-terminus, a central PX domain, and a
          C-terminal PB1 domain. Bem1p is a scaffolding protein
          that is critical for proper Cdc42p activation during
          bud formation in yeast. During budding and mating,
          Bem1p migrates to the plasma membrane where it can
          serve as an adaptor for Cdc42p and some other proteins.
          Bem1p also functions as an effector of the G1 cyclin
          Cln3p and the cyclin-dependent kinase Cdc28p in
          promoting vacuolar fusion. SH3 domains bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs; they play a
          role in the regulation of enzymes by intramolecular
          interactions, changing the subcellular localization of
          signal pathway components and mediate multiprotein
          complex assemblies.
          Length = 54

 Score = 35.3 bits (82), Expect = 0.002
 Identities = 18/57 (31%), Positives = 24/57 (42%), Gaps = 10/57 (17%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTN-ASDDEWWQARRVLPSGDEQGIGIVP 76
          RAL+DY            L F  GD  HV       EW++A    P   ++  G+VP
Sbjct: 3  RALYDYRAQT-----PGELSFSKGDFFHVIGEEDQGEWYEATN--PVTGKR--GLVP 50


>gnl|CDD|212979 cd12046, SH3_p67phox_C, C-terminal (or second) Src Homology 3
          domain of the p67phox subunit of NADPH oxidase.
          p67phox, also called Neutrophil cytosol factor 2
          (NCF-2), is a cytosolic subunit of the phagocytic NADPH
          oxidase complex (also called Nox2 or gp91phox) which
          plays a crucial role in the cellular response to
          bacterial infection. NADPH oxidase catalyzes the
          transfer of electrons from NADPH to oxygen during
          phagocytosis forming superoxide and reactive oxygen
          species. p67phox plays a regulatory role and contains
          N-terminal TPR, first SH3 (or N-terminal or central
          SH3), PB1, and C-terminal SH3 domains. It binds, via
          its C-terminal SH3 domain, to a proline-rich region of
          p47phox and upon activation, this complex assembles
          with flavocytochrome b558, the Nox2-p22phox
          heterodimer. Concurrently, RacGTP translocates to the
          membrane and interacts with the TPR domain of p67phox,
          which leads to the activation of NADPH oxidase. The PB1
          domain of p67phox binds to its partner PB1 domain in
          p40phox, and this facilitates the assembly of
          p47phox-p67phox at the membrane. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 53

 Score = 35.2 bits (81), Expect = 0.002
 Identities = 17/57 (29%), Positives = 29/57 (50%), Gaps = 13/57 (22%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQG-IGIVPS 77
          ALF Y+ ++ + L      F  GD++ V +  +++W +       G  +G IGI PS
Sbjct: 4  ALFSYEASQPEDLE-----FQKGDVILVLSKVNEDWLE-------GQCKGKIGIFPS 48


>gnl|CDD|212816 cd11883, SH3_Sdc25, Src Homology 3 domain of Sdc25/Cdc25 guanine
          nucleotide exchange factors.  This subfamily is
          composed of the Saccharomyces cerevisiae guanine
          nucleotide exchange factors (GEFs) Sdc25 and Cdc25, and
          similar proteins. These GEFs regulate Ras by
          stimulating the GDP/GTP exchange on Ras. Cdc25 is
          involved in the Ras/PKA pathway that plays an important
          role in the regulation of metabolism, stress responses,
          and proliferation, depending on available nutrients and
          conditions. Proteins in this subfamily contain an
          N-terminal SH3 domain as well as REM (Ras exchanger
          motif) and RasGEF domains at the C-terminus. SH3
          domains bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs; they play a role in the regulation of enzymes
          by intramolecular interactions, changing the
          subcellular localization of signal pathway components
          and mediate multiprotein complex assemblies.
          Length = 55

 Score = 34.9 bits (81), Expect = 0.002
 Identities = 13/38 (34%), Positives = 18/38 (47%), Gaps = 5/38 (13%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWW 58
           AL+D+ P   + L      F  GDI++V N     WW
Sbjct: 3  VALYDFTPKSKNQLS-----FKAGDIIYVLNKDPSGWW 35


>gnl|CDD|212793 cd11859, SH3_ZO, Src homology 3 domain of the Tight junction
          proteins, Zonula occludens (ZO) proteins.  ZO proteins
          are scaffolding proteins that associate with each other
          and with other proteins of the tight junction, zonula
          adherens, and gap junctions. They play roles in
          regulating cytoskeletal dynamics at these cell
          junctions. They are considered members of the MAGUK
          (membrane-associated guanylate kinase) protein family,
          which is characterized by the presence of a core of
          three domains: PDZ, SH3, and guanylate kinase (GuK).
          The GuK domain in MAGUK proteins is enzymatically
          inactive; instead, the domain mediates protein-protein
          interactions and associates intramolecularly with the
          SH3 domain. Vertebrates contain three ZO proteins
          (ZO-1, ZO-2, and ZO-3) with redundant and non-redundant
          roles. They contain three PDZ domains, followed by SH3
          and GuK domains; in addition, ZO-1 and ZO-2 contains a
          proline-rich (PR) actin binding domain at the
          C-terminus while ZO-3 contains this PR domain between
          the second and third PDZ domains. The C-terminal
          regions of the three ZO proteins are unique. The SH3
          domain of ZO-1 has been shown to bind ZONAB, ZAK,
          afadin, and Galpha12. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 62

 Score = 34.6 bits (80), Expect = 0.003
 Identities = 20/67 (29%), Positives = 29/67 (43%), Gaps = 8/67 (11%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDE---WWQARRVLPSGDEQGIGIV 75
          + R  FDY+           L F  G++ HV +         WQA RV  +  E   G++
Sbjct: 1  YIRTHFDYEKP-----AKGELSFKKGEVFHVVDTLYQGTVGSWQAVRVGRNHQELERGVI 55

Query: 76 PSKKRWE 82
          P+K R E
Sbjct: 56 PNKSRAE 62


>gnl|CDD|212758 cd11824, SH3_PSTPIP1, Src homology 3 domain of
          Proline-Serine-Threonine Phosphatase-Interacting
          Protein 1.  PSTPIP1, also called CD2 Binding Protein 1
          (CD2BP1), is mainly expressed in hematopoietic cells.
          It is a binding partner of the cell surface receptor
          CD2 and PTP-PEST, a tyrosine phosphatase which
          functions in cell motility and Rac1 regulation. It also
          plays a role in the activation of the Wiskott-Aldrich
          syndrome protein (WASP), which couples actin
          rearrangement and T cell activation. Mutations in the
          gene encoding PSTPIP1 cause the autoinflammatory
          disorder known as PAPA (pyogenic sterile arthritis,
          pyoderma gangrenosum, and acne) syndrome. PSTPIP1
          contains an N-terminal F-BAR domain, PEST motifs, and a
          C-terminal SH3 domain. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 53

 Score = 34.3 bits (79), Expect = 0.003
 Identities = 15/50 (30%), Positives = 21/50 (42%), Gaps = 7/50 (14%)

Query: 19 FSRALFDYDPTKDDGLP-SRGLPFHYGDILHVTNASDDEWWQARRVLPSG 67
              L+DY   +DD L  S+G      D++ V    +D WW   R    G
Sbjct: 1  KYSVLYDYTAQEDDELSISKG------DVVAVIEKGEDGWWTVERNGQKG 44


>gnl|CDD|212994 cd12061, SH3_betaPIX, Src Homology 3 domain of beta-Pak
          Interactive eXchange factor.  Beta-PIX, also called Rho
          guanine nucleotide exchange factor 7 (ARHGEF7) or Cool
          (Cloned out of Library)-1, activates small GTPases by
          exchanging bound GDP for free GTP. It acts as a GEF for
          both Cdc42 and Rac 1, and plays important roles in
          regulating neuroendocrine exocytosis, focal adhesion
          maturation, cell migration, synaptic vesicle
          localization, and insulin secretion. PIX proteins
          contain an N-terminal SH3 domain followed by RhoGEF
          (also called Dbl-homologous or DH) and Pleckstrin
          Homology (PH) domains, and a C-terminal leucine-zipper
          domain for dimerization. The SH3 domain of PIX binds to
          an atypical PxxxPR motif in p21-activated kinases
          (PAKs) with high affinity. The binding of PAKs to PIX
          facilitate the localization of PAKs to focal complexes
          and also localizes PAKs to PIX targets Cdc43 and Rac,
          leading to the activation of PAKs. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 54

 Score = 34.3 bits (78), Expect = 0.004
 Identities = 14/40 (35%), Positives = 21/40 (52%), Gaps = 5/40 (12%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQA 60
          RA F++  T +D L      F  GD++HVT   +  WW+ 
Sbjct: 3  RAKFNFQQTNEDELS-----FSKGDVIHVTRVEEGGWWEG 37


>gnl|CDD|212703 cd11769, SH3_CSK, Src Homology 3 domain of C-terminal Src kinase.
           CSK is a cytoplasmic (or nonreceptor) tyr kinase
          containing the Src homology domains, SH3 and SH2,
          N-terminal to the catalytic tyr kinase domain. They
          negatively regulate the activity of Src kinases that
          are anchored to the plasma membrane. To inhibit Src
          kinases, CSK is translocated to the membrane via
          binding to specific transmembrane proteins, G-proteins,
          or adaptor proteins near the membrane. CSK catalyzes
          the tyr phosphorylation of the regulatory C-terminal
          tail of Src kinases, resulting in their inactivation.
          It is expressed in a wide variety of tissues and plays
          a role, as a regulator of Src, in cell proliferation,
          survival, and differentiation, and consequently, in
          cancer development and progression. In addition, CSK
          also shows Src-independent functions. It is a critical
          component in G-protein signaling, and plays a role in
          cytoskeletal reorganization and cell migration. SH3
          domains are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 57

 Score = 34.2 bits (79), Expect = 0.004
 Identities = 16/56 (28%), Positives = 27/56 (48%), Gaps = 11/56 (19%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDD-EWWQARRVLPSGDEQGIGIVP 76
          A ++++     G     LPF  GDIL +   + D  W++A+     G E   G++P
Sbjct: 6  AKYNFN-----GASEEDLPFKKGDILTIVAVTKDPNWYKAKNK--DGRE---GMIP 51


>gnl|CDD|212974 cd12041, SH3_CACNB1, Src Homology 3 domain of Voltage-dependent
          L-type calcium channel subunit beta-1.  The beta1
          subunit of voltage-dependent calcium channels (Ca(V)s)
          is one of four beta subunits present in vertebrates. It
          is the only beta subunit, as the beta1a variant,
          expressed in skeletal muscle; the beta1b variant is
          also widely expressed in other tissues including the
          heart and brain. Knockout of the beta1 gene in mice
          results in embryonic lethality, demonstrating its
          importance in development. Ca(V)s are multi-protein
          complexes that regulate the entry of calcium into
          cells. They impact muscle contraction, neuronal
          migration, hormone and neurotransmitter release, and
          the activation of calcium-dependent signaling pathways.
          They are composed of four subunits: alpha1,
          alpha2delta, beta, and gamma. The beta subunit is a
          soluble and intracellular protein that interacts with
          the transmembrane alpha1 subunit. It facilitates the
          trafficking and proper localization of the alpha1
          subunit to the cellular plasma membrane. Vertebrates
          contain four different beta subunits from distinct
          genes (beta1-4); each exists as multiple splice
          variants. All are expressed in the brain while other
          tissues show more specific expression patterns. The
          beta subunits show similarity to MAGUK
          (membrane-associated guanylate kinase) proteins in that
          they contain SH3 and inactive guanylate kinase (GuK)
          domains; however, they do not appear to contain a PDZ
          domain. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 68

 Score = 34.6 bits (79), Expect = 0.004
 Identities = 19/59 (32%), Positives = 31/59 (52%), Gaps = 5/59 (8%)

Query: 26 YDPTKDDGLPSRGL--PFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSKKRWE 82
          Y+P+  D +P +G+   F   D LH+    +++WW  R V   G E  +G +PS  + E
Sbjct: 13 YNPSPGDDVPVQGMAISFEPKDFLHIKEKYNNDWWIGRLV-KEGCE--VGFIPSPVKLE 68


>gnl|CDD|212891 cd11958, SH3_RUSC1, Src homology 3 domain of RUN and SH3
          domain-containing protein 1.  RUSC1, also called NESCA
          (New molecule containing SH3 at the carboxy-terminus),
          is highly expressed in the brain and is translocated to
          the nuclear membrane from the cytoplasm upon
          stimulation with neurotrophin. It plays a role in
          facilitating neurotrophin-dependent neurite outgrowth.
          It also interacts with NEMO (or IKKgamma) and may
          function in NEMO-mediated activation of NF-kB. RUSC
          proteins are adaptor proteins consisting of RUN,
          leucine zipper, and SH3 domains. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 51

 Score = 34.0 bits (78), Expect = 0.004
 Identities = 18/56 (32%), Positives = 27/56 (48%), Gaps = 12/56 (21%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVP 76
          RAL D+  ++        L F  G+ L V    D++W + RR    GD +  G+VP
Sbjct: 3  RALCDHAGSES------QLSFRKGEELQVLGTVDEDWIRCRR----GDRE--GLVP 46


>gnl|CDD|212702 cd11768, SH3_Tec_like, Src Homology 3 domain of Tec-like Protein
          Tyrosine Kinases.  The Tec (Tyrosine kinase expressed
          in hepatocellular carcinoma) subfamily is composed of
          Tec, Btk, Bmx (Etk), Itk (Tsk, Emt), Rlk (Txk), and
          similar proteins. They are cytoplasmic (or nonreceptor)
          tyr kinases containing Src homology protein interaction
          domains (SH3, SH2) N-terminal to the catalytic tyr
          kinase domain. Most Tec subfamily members (except Rlk)
          also contain an N-terminal pleckstrin homology (PH)
          domain, which binds the products of PI3K and allows
          membrane recruitment and activation. In addition, some
          members contain the Tec homology (TH) domain, which
          contains proline-rich and zinc-binding regions. Tec
          kinases are expressed mainly by haematopoietic cells,
          although Tec and Bmx are also found in endothelial
          cells. B-cells express Btk and Tec, while T-cells
          express Itk, Txk, and Tec. Collectively, Tec kinases
          are expressed in a variety of myeloid cells such as
          mast cells, platelets, macrophages, and dendritic
          cells. Each Tec kinase shows a distinct cell-type
          pattern of expression. The function of Tec kinases in
          lymphoid cells have been studied extensively. They play
          important roles in the development, differentiation,
          maturation, regulation, survival, and function of
          B-cells and T-cells. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 54

 Score = 33.8 bits (78), Expect = 0.005
 Identities = 18/57 (31%), Positives = 28/57 (49%), Gaps = 12/57 (21%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQG-IGIVPS 77
          AL+D+ P +   LP        G+   V + S++ WW+AR      D+ G  G +PS
Sbjct: 4  ALYDFQPIEPGDLPLEK-----GEEYVVLDDSNEHWWRAR------DKNGNEGYIPS 49


>gnl|CDD|212973 cd12040, SH3_CACNB2, Src Homology 3 domain of Voltage-dependent
          L-type calcium channel subunit beta2.  The beta2
          subunit of voltage-dependent calcium channels (Ca(V)s)
          is one of four beta subunits present in vertebrates. It
          is expressed in the heart and is present in specific
          neuronal cells including cerebellar Purkinje cells,
          hippocampal pyramidal neurons, and photoreceptors.
          Knockout of the beta2 gene in mice results in embryonic
          lethality, demonstrating its importance in development.
          Ca(V)s are multi-protein complexes that regulate the
          entry of calcium into cells. They impact muscle
          contraction, neuronal migration, hormone and
          neurotransmitter release, and the activation of
          calcium-dependent signaling pathways. They are composed
          of four subunits: alpha1, alpha2delta, beta, and gamma.
          The beta subunit is a soluble and intracellular protein
          that interacts with the transmembrane alpha1 subunit.
          It facilitates the trafficking and proper localization
          of the alpha1 subunit to the cellular plasma membrane.
          Vertebrates contain four different beta subunits from
          distinct genes (beta1-4); each exists as multiple
          splice variants. All are expressed in the brain while
          other tissues show more specific expression patterns.
          The beta subunits show similarity to MAGUK
          (membrane-associated guanylate kinase) proteins in that
          they contain SH3 and inactive guanylate kinase (GuK)
          domains; however, they do not appear to contain a PDZ
          domain. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 69

 Score = 34.2 bits (78), Expect = 0.005
 Identities = 17/59 (28%), Positives = 26/59 (44%), Gaps = 5/59 (8%)

Query: 26 YDPTKDDGLP--SRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSKKRWE 82
          Y    +D +P     + F   D LHV    +++WW  R V    +   IG +PS  + E
Sbjct: 14 YSAAHEDDVPVPGMAISFEAKDFLHVKEKFNNDWWIGRLVKEGCE---IGFIPSPVKLE 69


>gnl|CDD|212696 cd11762, SH3_FCHSD_2, Second Src Homology 3 domain of FCH and
          double SH3 domains proteins.  This group is composed of
          FCH and double SH3 domains protein 1 (FCHSD1) and
          FCHSD2. These proteins have a common domain structure
          consisting of an N-terminal F-BAR (FES-CIP4 Homology
          and Bin/Amphiphysin/Rvs), two SH3, and C-terminal
          proline-rich domains. They have only been characterized
          in silico and their functions remain unknown. This
          group also includes the insect protein, nervous wreck,
          which acts as a regulator of synaptic growth signaling.
          SH3 domains are protein interaction domains that bind
          to proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 57

 Score = 33.9 bits (78), Expect = 0.005
 Identities = 19/64 (29%), Positives = 28/64 (43%), Gaps = 17/64 (26%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNAS----DDEWWQARRVLPSGDEQG-IG 73
            RAL+DY+   D+      L F  G I+ +        DD WW+       G+  G +G
Sbjct: 1  LVRALYDYEAQSDE-----ELSFPEGAIIRILRKDDNGVDDGWWE-------GEFNGRVG 48

Query: 74 IVPS 77
          + PS
Sbjct: 49 VFPS 52


>gnl|CDD|212975 cd12042, SH3_CACNB3, Src Homology 3 domain of Voltage-dependent
          L-type calcium channel subunit beta3.  The beta3
          subunit of voltage-dependent calcium channels (Ca(V)s)
          is one of four beta subunits present in vertebrates. It
          is the main beta subunit present in smooth muscles and
          is strongly expressed in the brain; it is predominant
          in the olfactory bulb, cortex, and hippocampus. It may
          play a role in regulating the NMDAR
          (N-methyl-d-aspartate receptor) activity in the
          hippocampus and thus, activity-dependent synaptic
          plasticity and cognitive behaviors. Ca(V)s are
          multi-protein complexes that regulate the entry of
          calcium into cells. They impact muscle contraction,
          neuronal migration, hormone and neurotransmitter
          release, and the activation of calcium-dependent
          signaling pathways. They are composed of four subunits:
          alpha1, alpha2delta, beta, and gamma. The beta subunit
          is a soluble and intracellular protein that interacts
          with the transmembrane alpha1 subunit. It facilitates
          the trafficking and proper localization of the alpha1
          subunit to the cellular plasma membrane. Vertebrates
          contain four different beta subunits from distinct
          genes (beta1-4); each exists as multiple splice
          variants. All are expressed in the brain while other
          tissues show more specific expression patterns. The
          beta subunits show similarity to MAGUK
          (membrane-associated guanylate kinase) proteins in that
          they contain SH3 and inactive guanylate kinase (GuK)
          domains; however, they do not appear to contain a PDZ
          domain. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 68

 Score = 34.2 bits (78), Expect = 0.005
 Identities = 18/54 (33%), Positives = 26/54 (48%), Gaps = 5/54 (9%)

Query: 31 DDGLPSRG--LPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSKKRWE 82
          D+  P +G  + F   D LH+     ++WW  R V   GD   I  +PS +R E
Sbjct: 18 DEECPVQGAAINFEAKDFLHIKEKYSNDWWIGRLVKEGGD---IAFIPSPQRLE 68


>gnl|CDD|212976 cd12043, SH3_CACNB4, Src Homology 3 domain of Voltage-dependent
          L-type calcium channel subunit beta4.  The beta4
          subunit of voltage-dependent calcium channels (Ca(V)s)
          is one of four beta subunits present in vertebrates. It
          is the only beta subunit expressed in the cochlea and
          is highly expressed in the brain, predominantly in the
          cerebellum. Ca(V)s are multi-protein complexes that
          regulate the entry of calcium into cells. They impact
          muscle contraction, neuronal migration, hormone and
          neurotransmitter release, and the activation of
          calcium-dependent signaling pathways. They are composed
          of four subunits: alpha1, alpha2delta, beta, and gamma.
          The beta subunit is a soluble and intracellular protein
          that interacts with the transmembrane alpha1 subunit.
          It facilitates the trafficking and proper localization
          of the alpha1 subunit to the cellular plasma membrane.
          Vertebrates contain four different beta subunits from
          distinct genes (beta1-4); each exists as multiple
          splice variants. All are expressed in the brain while
          other tissues show more specific expression patterns.
          The beta subunits show similarity to MAGUK
          (membrane-associated guanylate kinase) proteins in that
          they contain SH3 and inactive guanylate kinase (GuK)
          domains; however, they do not appear to contain a PDZ
          domain. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 68

 Score = 34.2 bits (78), Expect = 0.006
 Identities = 16/53 (30%), Positives = 25/53 (47%), Gaps = 3/53 (5%)

Query: 30 KDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSKKRWE 82
          +D  +P   + F   D LH+    +++WW  R V    +   IG +PS  R E
Sbjct: 19 EDVPVPGTAISFDAKDFLHIKEKYNNDWWIGRLVKEGCE---IGFIPSPLRLE 68


>gnl|CDD|212940 cd12007, SH3_Yes, Src homology 3 domain of Yes Protein Tyrosine
          Kinase.  Yes (or c-Yes) is a member of the Src
          subfamily of proteins, which are cytoplasmic (or
          non-receptor) PTKs. c-Yes kinase is the cellular
          homolog of the oncogenic protein (v-Yes) encoded by the
          Yamaguchi 73 and Esh sarcoma viruses. It displays
          functional overlap with other Src subfamily members,
          particularly Src. It also shows some unique functions
          such as binding to occludins, transmembrane proteins
          that regulate extracellular interactions in tight
          junctions. Yes also associates with a number of
          proteins in different cell types that Src does not
          interact with, like JAK2 and gp130 in pre-adipocytes,
          and Pyk2 in treated pulmonary vein endothelial cells.
          Although the biological function of Yes remains
          unclear, it appears to have a role in regulating
          cell-cell interactions and vesicle trafficking in
          polarized cells. Src kinases contain an N-terminal SH4
          domain with a myristoylation site, followed by SH3 and
          SH2 domains, a tyr kinase domain, and a regulatory
          C-terminal region containing a conserved tyr. They are
          activated by autophosphorylation at the tyr kinase
          domain, but are negatively regulated by phosphorylation
          at the C-terminal tyr by Csk (C-terminal Src Kinase).
          The SH3 domain of Src kinases contributes to substrate
          recruitment by binding adaptor proteins/substrates, and
          regulation of kinase activity through an intramolecular
          interaction. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 58

 Score = 33.5 bits (76), Expect = 0.007
 Identities = 14/43 (32%), Positives = 24/43 (55%), Gaps = 7/43 (16%)

Query: 22 ALFDYDP-TKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRV 63
          AL+DY+  T +D      L F  G+   + N ++ +WW+AR +
Sbjct: 5  ALYDYEARTTED------LSFKKGERFQIINNTEGDWWEARSI 41


>gnl|CDD|212881 cd11948, SH3_GRAP_N, N-terminal Src homology 3 domain of
          GRB2-related adaptor protein.  GRAP is a GRB-2 like
          adaptor protein that is highly expressed in lymphoid
          tissues. It acts as a negative regulator of T cell
          receptor (TCR)-induced lymphocyte proliferation by
          downregulating the signaling to the Ras/ERK pathway. It
          has been identified as a regulator of TGFbeta signaling
          in diabetic kidney tubules and may have a role in the
          pathogenesis of the disease. GRAP contains an
          N-terminal SH3 domain, a central SH2 domain, and a
          C-terminal SH3 domain. The N-terminal SH3 domain of the
          related protein GRB2 binds to Sos and Sos-derived
          proline-rich peptides. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 54

 Score = 33.3 bits (76), Expect = 0.007
 Identities = 15/39 (38%), Positives = 21/39 (53%), Gaps = 5/39 (12%)

Query: 20 SRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWW 58
          + AL+ +  T+ D LP     F  GDIL + N  DD+ W
Sbjct: 2  AVALYSFQATESDELP-----FQKGDILKILNMEDDQNW 35


>gnl|CDD|212753 cd11819, SH3_Cortactin_like, Src homology 3 domain of Cortactin
          and related proteins.  This subfamily includes
          cortactin, Abp1 (actin-binding protein 1),
          hematopoietic lineage cell-specific protein 1 (HS1),
          and similar proteins. These proteins are involved in
          regulating actin dynamics through direct or indirect
          interaction with the Arp2/3 complex, which is required
          to initiate actin polymerization. They all contain at
          least one C-terminal SH3 domain. Cortactin and HS1 bind
          Arp2/3 and actin through an N-terminal region that
          contains an acidic domain and several copies of a
          repeat domain found in cortactin and HS1. Abp1 binds
          actin via an N-terminal actin-depolymerizing factor
          (ADF) homology domain. Yeast Abp1 binds Arp2/3 directly
          through two acidic domains. Mammalian Abp1 does not
          directly interact with Arp2/3; instead, it regulates
          actin dynamics indirectly by interacting with dynamin
          and WASP family proteins. The C-terminal region of
          these proteins acts as an adaptor or scaffold that can
          connect membrane trafficking and signaling proteins
          that bind the SH3 domain within the actin network. SH3
          domains are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 54

 Score = 33.4 bits (77), Expect = 0.007
 Identities = 16/57 (28%), Positives = 25/57 (43%), Gaps = 10/57 (17%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          +AL+DY   +D+      + F  GDI+      D+ WW    V   G     G+ P+
Sbjct: 3  KALYDYQAAEDN-----EISFVEGDIITQIEQIDEGWWLG--VNAKGQ---KGLFPA 49


>gnl|CDD|212781 cd11847, SH3_Brk, Src homology 3 domain of Brk (Breast tumor
          kinase) Protein Tyrosine Kinase (PTK), also called
          PTK6.  Brk is a cytoplasmic (or non-receptor) PTK with
          limited homology to Src kinases. It has been found to
          be overexpressed in a majority of breast tumors. It
          plays roles in normal cell differentiation,
          proliferation, survival, migration, and cell cycle
          progression. Brk substrates include RNA-binding
          proteins (SLM-1/2, Sam68), transcription factors
          (STAT3/5), and signaling molecules (Akt, paxillin,
          IRS-4). Src kinases in general contain an N-terminal
          SH4 domain with a myristoylation site, followed by SH3
          and SH2 domains, a tyr kinase domain, and a regulatory
          C-terminal region containing a conserved tyr; they are
          activated by autophosphorylation at the tyr kinase
          domain, but are negatively regulated by phosphorylation
          at the C-terminal tyr by Csk (C-terminal Src Kinase).
          However, Brk lacks the N-terminal myristoylation site.
          The SH3 domain of Src kinases contributes to substrate
          recruitment by binding adaptor proteins/substrates, and
          regulation of kinase activity through an intramolecular
          interaction. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 58

 Score = 33.3 bits (76), Expect = 0.008
 Identities = 17/55 (30%), Positives = 24/55 (43%), Gaps = 6/55 (10%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVP 76
          AL+D+    D+ L      F  GD   +   S D WW A ++  +G     G VP
Sbjct: 4  ALWDFKARGDEELS-----FQAGDQFRIAERSGD-WWTALKLDRAGGVVAQGFVP 52


>gnl|CDD|212906 cd11973, SH3_ASEF, Src homology 3 domain of APC-Stimulated
          guanine nucleotide Exchange Factor.  ASEF, also called
          ARHGEF4, exists in an autoinhibited form and is
          activated upon binding of the tumor suppressor APC
          (adenomatous polyposis coli). GEFs activate small
          GTPases by exchanging bound GDP for free GTP. ASEF can
          activate Rac1 or Cdc42. Truncated ASEF, which is found
          in colorectal cancers, is constitutively active and has
          been shown to promote angiogenesis and cancer cell
          migration. ASEF contains a SH3 domain followed by
          RhoGEF (also called Dbl-homologous or DH) and
          Pleckstrin Homology (PH) domains. In its autoinhibited
          form, the SH3 domain of ASEF forms an extensive
          interface with the DH and PH domains, blocking the Rac
          binding site. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 73

 Score = 33.8 bits (77), Expect = 0.008
 Identities = 19/51 (37%), Positives = 28/51 (54%), Gaps = 5/51 (9%)

Query: 11 LISTHLFSFSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQAR 61
          LIS      + AL+D+  T DD    + L F  GD++ V +A++ EWW  R
Sbjct: 11 LISDGSVVCAEALWDH-VTMDD----QELGFKAGDVIEVMDATNKEWWWGR 56


>gnl|CDD|212810 cd11877, SH3_PIX, Src Homology 3 domain of Pak Interactive
          eXchange factors.  PIX proteins are Rho guanine
          nucleotide exchange factors (GEFs), which activate
          small GTPases by exchanging bound GDP for free GTP.
          They act as GEFs for both Cdc42 and Rac 1, and have
          been implicated in cell motility, adhesion, neurite
          outgrowth, and cell polarity. Vertebrates contain two
          proteins from the PIX subfamily, alpha-PIX and
          beta-PIX. Alpha-PIX, also called ARHGEF6, is localized
          in dendritic spines where it regulates spine
          morphogenesis. Mutations in the ARHGEF6 gene cause
          X-linked intellectual disability in humans. Beta-PIX
          play roles in regulating neuroendocrine exocytosis,
          focal adhesion maturation, cell migration, synaptic
          vesicle localization, and insulin secretion. PIX
          proteins contain an N-terminal SH3 domain followed by
          RhoGEF (also called Dbl-homologous or DH) and
          Pleckstrin Homology (PH) domains, and a C-terminal
          leucine-zipper domain for dimerization. The SH3 domain
          of PIX binds to an atypical PxxxPR motif in
          p21-activated kinases (PAKs) with high affinity. The
          binding of PAKs to PIX facilitate the localization of
          PAKs to focal complexes and also localizes PAKs to PIX
          targets Cdc43 and Rac, leading to the activation of
          PAKs. SH3 domains are protein interaction domains that
          bind to proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 53

 Score = 33.1 bits (76), Expect = 0.008
 Identities = 14/39 (35%), Positives = 21/39 (53%), Gaps = 5/39 (12%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQ 59
          RA F+++ T +D L      F  GDI+ VT   +  WW+
Sbjct: 3  RAKFNFEGTNEDELS-----FDKGDIITVTQVVEGGWWE 36


>gnl|CDD|212820 cd11887, SH3_Bbc1, Src Homology 3 domain of Bbc1 and similar
          domains.  This subfamily is composed of Saccharomyces
          cerevisiae Bbc1p, also called Mti1p (Myosin tail
          region-interacting protein), and similar proteins.
          Bbc1p interacts with and regulates type I myosins in
          yeast, Myo3p and Myo5p, which are involved in actin
          cytoskeletal reorganization. It also binds and inhibits
          Las17, a WASp family protein that functions as an
          activator of the Arp2/3 complex. Bbc1p contains an
          N-terminal SH3 domain. SH3 domains bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs; they play a role in the
          regulation of enzymes by intramolecular interactions,
          changing the subcellular localization of signal pathway
          components and mediate multiprotein complex assemblies.
          Length = 60

 Score = 33.1 bits (76), Expect = 0.009
 Identities = 16/56 (28%), Positives = 27/56 (48%), Gaps = 6/56 (10%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVP 76
          +AL+ Y+   +D L      F  G ++ VT   D +W+    V  +G+ +  GI P
Sbjct: 5  KALYPYESDHEDDLN-----FDVGQLITVTEEEDADWYFGEYVDSNGNTK-EGIFP 54


>gnl|CDD|212755 cd11821, SH3_ASAP, Src homology 3 domain of ArfGAP with SH3
          domain, ankyrin repeat and PH domain containing
          proteins.  ASAPs are Arf GTPase activating proteins
          (GAPs) and they function in regulating cell growth,
          migration, and invasion. They contain an N-terminal BAR
          domain, followed by a Pleckstrin homology (PH) domain,
          an Arf GAP domain, ankyrin (ANK) repeats, and a
          C-terminal SH3 domain. Vertebrates contain at least
          three members, ASAP1, ASAP2, and ASAP3, but some ASAP3
          proteins do not seem to harbor a C-terminal SH3 domain.
          ASAP1 and ASAP2 show GTPase activating protein (GAP)
          activity towards Arf1 and Arf5. They do not show GAP
          activity towards Arf6, but are able to mediate Arf6
          signaling by binding stably to GTP-Arf6. ASAP3 is an
          Arf6-specific GAP. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 53

 Score = 32.7 bits (75), Expect = 0.011
 Identities = 17/38 (44%), Positives = 20/38 (52%), Gaps = 5/38 (13%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWW 58
          RAL+D     DD L      F  G+I+ VT   DDEWW
Sbjct: 3  RALYDCQADNDDELT-----FSEGEIIVVTGEEDDEWW 35


>gnl|CDD|212928 cd11995, SH3_Intersectin1_5, Fifth Src homology 3 domain (or
          SH3E) of Intersectin-1.  Intersectin-1 (ITSN1) is an
          adaptor protein that functions in exo- and endocytosis,
          actin cytoskeletal reorganization, and signal
          transduction. It plays a role in clathrin-coated pit
          (CCP) formation. It binds to many proteins through its
          multidomain structure and facilitate the assembly of
          multimeric complexes. ITSN1 localizes in membranous
          organelles, CCPs, the Golgi complex, and may be
          involved in the cell membrane trafficking system. It
          exists in alternatively spliced short and long
          isoforms. The short isoform contains two Eps15 homology
          domains (EH1 and EH2), a coiled-coil region and five
          SH3 domains (SH3A-E), while the long isoform, in
          addition, contains RhoGEF (also called Dbl-homologous
          or DH), Pleckstrin homology (PH) and C2 domains. The
          fifth SH3 domain (or SH3E) of ITSN1 has been shown to
          bind many protein partners including SGIP1, Sos1,
          dynamin1/2, CIN85, c-Cbl, SHIP2, N-WASP, and
          synaptojanin-1, among others. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 54

 Score = 33.0 bits (75), Expect = 0.012
 Identities = 18/57 (31%), Positives = 27/57 (47%), Gaps = 13/57 (22%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQG-IGIVPS 77
           ++DY    DD L      F  G I++V N  D +WW+       G+  G +G+ PS
Sbjct: 5  GMYDYTAQNDDELA-----FSKGQIINVLNKEDPDWWK-------GELNGQVGLFPS 49


>gnl|CDD|212721 cd11787, SH3_SH3RF_2, Second Src Homology 3 domain of SH3 domain
          containing ring finger proteins.  This model represents
          the second SH3 domain of SH3RF1 (or POSH), SH3RF2 (or
          POSHER), SH3RF3 (POSH2), and similar domains. Members
          of this family are scaffold proteins that function as
          E3 ubiquitin-protein ligases. They all contain an
          N-terminal RING finger domain and multiple SH3 domains;
          SH3RF1 and SH3RF3 have four SH3 domains while SH3RF2
          has three. SH3RF1 plays a role in calcium homeostasis
          through the control of the ubiquitin domain protein
          Herp. It may also have a role in regulating death
          receptor mediated and JNK mediated apoptosis. SH3RF3
          interacts with p21-activated kinase 2 (PAK2) and
          GTP-loaded Rac1. It may play a role in regulating JNK
          mediated apoptosis in certain conditions. SH3RF2 acts
          as an anti-apoptotic regulator of the JNK pathway by
          binding to and promoting the degradation of SH3RF1. SH3
          domains are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 53

 Score = 32.7 bits (75), Expect = 0.013
 Identities = 18/58 (31%), Positives = 28/58 (48%), Gaps = 8/58 (13%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVP 76
            +AL+D++   +D      L F  GD++ V    D+ W + R     GD+  IGI P
Sbjct: 1  QCKALYDFEMKDED--EKDCLTFKKGDVITVIRRVDENWAEGRL----GDK--IGIFP 50


>gnl|CDD|212738 cd11804, SH3_GRB2_like_N, N-terminal Src homology 3 domain of
          Growth factor receptor-bound protein 2 (GRB2) and
          related proteins.  This family includes the adaptor
          protein GRB2 and related proteins including Drosophila
          melanogaster Downstream of receptor kinase (DRK),
          Caenorhabditis elegans Sex muscle abnormal protein 5
          (Sem-5), GRB2-related adaptor protein (GRAP), GRAP2,
          and similar proteins. Family members contain an
          N-terminal SH3 domain, a central SH2 domain, and a
          C-terminal SH3 domain. GRB2/Sem-5/DRK is a critical
          signaling molecule that regulates the Ras pathway by
          linking tyrosine kinases to the Ras guanine nucleotide
          releasing protein Sos (son of sevenless), which
          converts Ras to the active GTP-bound state. GRAP2 plays
          an important role in T cell receptor (TCR) signaling by
          promoting the formation of the SLP-76:LAT complex,
          which couples the TCR to the Ras pathway. GRAP acts as
          a negative regulator of T cell receptor (TCR)-induced
          lymphocyte proliferation by downregulating the
          signaling to the Ras/ERK pathway. The N-terminal SH3
          domain of GRB2 binds to Sos and Sos-derived
          proline-rich peptides. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 52

 Score = 32.3 bits (74), Expect = 0.014
 Identities = 14/39 (35%), Positives = 17/39 (43%), Gaps = 5/39 (12%)

Query: 20 SRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWW 58
          + A  D+  T +D L      F  G IL V N  DD  W
Sbjct: 2  AVAKHDFKATAEDELS-----FKKGSILKVLNMEDDPNW 35


>gnl|CDD|212785 cd11851, SH3_RIM-BP, Src homology 3 domains of Rab3-interacting
          molecules (RIMs) binding proteins.  RIMs binding
          proteins (RBPs, RIM-BPs) associate with calcium
          channels present in photoreceptors, neurons, and hair
          cells; they interact simultaneously with specific
          calcium channel subunits, and active zone proteins,
          RIM1 and RIM2. RIMs are part of the matrix at the
          presynaptic active zone and are associated with
          synaptic vesicles through their interaction with the
          small GTPase Rab3. RIM-BPs play a role in regulating
          synaptic transmission by serving as adaptors and
          linking calcium channels with the synaptic vesicle
          release machinery. RIM-BPs contain three SH3 domains
          and two to three fibronectin III repeats. Invertebrates
          contain one, while vertebrates contain at least two
          RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called
          peripheral-type benzodiazapine receptor associated
          protein 1 (PRAX-1). Mammals contain a third protein,
          RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly
          expressed in the brain where they display overlapping
          but distinct expression patterns, while RIM-BP3 is
          almost exclusively expressed in the testis and is
          essential in spermiogenesis. The SH3 domains of RIM-BPs
          bind to the PxxP motifs of RIM1, RIM2, and L-type
          (alpha1D) and N-type (alpha1B) calcium channel
          subunits. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 62

 Score = 32.7 bits (75), Expect = 0.014
 Identities = 13/37 (35%), Positives = 19/37 (51%), Gaps = 2/37 (5%)

Query: 21 RALFDYDP--TKDDGLPSRGLPFHYGDILHVTNASDD 55
           AL+DY+P     +  P   L FH GD++ V    D+
Sbjct: 3  VALYDYNPETMSPNDDPEEELSFHAGDVVRVYGPMDE 39


>gnl|CDD|212821 cd11888, SH3_ARHGAP9_like, Src Homology 3 domain of Rho
          GTPase-activating protein 9 and similar proteins.  This
          subfamily is composed of Rho GTPase-activating proteins
          including mammalian ARHGAP9, and vertebrate ARHGAPs 12
          and 27. RhoGAPs (or ARHGAPs) bind to Rho proteins and
          enhance the hydrolysis rates of bound GTP. ARHGAP9
          functions as a GAP for Rac and Cdc42, but not for RhoA.
          It negatively regulates cell migration and adhesion. It
          also acts as a docking protein for the MAP kinases Erk2
          and p38alpha, and may facilitate cross-talk between the
          Rho GTPase and MAPK pathways to control actin
          remodeling. ARHGAP27, also called CAMGAP1, shows GAP
          activity towards Rac1 and Cdc42. It binds the adaptor
          protein CIN85 and may play a role in clathrin-mediated
          endocytosis. ARHGAP12 has been shown to display GAP
          activity towards Rac1. It plays a role in regulating
          HFG-driven cell growth and invasiveness. ARHGAPs in
          this subfamily contain SH3, WW, Pleckstin homology
          (PH), and RhoGAP domains. SH3 domains bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs; they play a
          role in the regulation of enzymes by intramolecular
          interactions, changing the subcellular localization of
          signal pathway components and mediate multiprotein
          complex assemblies.
          Length = 54

 Score = 32.3 bits (74), Expect = 0.015
 Identities = 13/42 (30%), Positives = 21/42 (50%), Gaps = 3/42 (7%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARR 62
            L+ ++ T  DG   R +    G+   +   S+D+WWQ RR
Sbjct: 3  VVLYPFEYTGKDG---RKVSIKEGERFLLLKKSNDDWWQVRR 41


>gnl|CDD|212701 cd11767, SH3_Nck_3, Third Src Homology 3 domain of Nck adaptor
          proteins.  This group contains the third SH3 domain of
          Nck, the first SH3 domain of Caenorhabditis elegans
          Ced-2 (Cell death abnormality protein 2), and similar
          domains. Nck adaptor proteins regulate actin
          cytoskeleton dynamics by linking proline-rich effector
          molecules to protein tyrosine kinases and
          phosphorylated signaling intermediates. They contain
          three SH3 domains and a C-terminal SH2 domain. They
          function downstream of the PDGFbeta receptor and are
          involved in Rho GTPase signaling and actin dynamics.
          Vertebrates contain two Nck adaptor proteins: Nck1
          (also called Nckalpha) and Nck2 (also called Nckbeta or
          Growth factor receptor-bound protein 4, Grb4), which
          show partly overlapping functions but also bind
          distinct targets. Their SH3 domains are involved in
          recruiting downstream effector molecules, such as the
          N-WASP/Arp2/3 complex, which when activated induces
          actin polymerization that results in the production of
          pedestals, or protrusions of the plasma membrane. The
          third SH3 domain of Nck appears to prefer ligands with
          a PxAPxR motif. SH3 domains are protein interaction
          domains that usually bind to proline-rich ligands with
          moderate affinity and selectivity, preferentially a
          PxxP motif. Ced-2 is a cell corpse engulfment protein
          that interacts with Ced-5 in a pathway that regulates
          the activation of Ced-10, a Rac small GTPase.
          Length = 56

 Score = 32.3 bits (74), Expect = 0.018
 Identities = 13/41 (31%), Positives = 19/41 (46%), Gaps = 7/41 (17%)

Query: 39 LPFHYGDILHVTN--ASDDEWWQARRVLPSGDEQGIGIVPS 77
          L F  G+ L +      D +WW+AR  L +      G+VP 
Sbjct: 16 LSFEKGERLEIIEKPEDDPDWWKARNALGT-----TGLVPR 51


>gnl|CDD|212792 cd11858, SH3_Myosin-I_fungi, Src homology 3 domain of Type I
          fungal Myosins.  Type I myosins (myosin-I) are
          actin-dependent motors in endocytic actin structures
          and actin patches. They play roles in membrane traffic
          in endocytic and secretory pathways, cell motility, and
          mechanosensing. Saccharomyces cerevisiae has two
          myosins-I, Myo3 and Myo5, which are involved in
          endocytosis and the polarization of the actin
          cytoskeleton. Myosin-I contains an N-terminal
          actin-activated ATPase, a phospholipid-binding TH1
          (tail homology 1) domain, and a C-terminal extension
          which includes an F-actin-binding TH2 domain, an SH3
          domain, and an acidic peptide that participates in
          activating the Arp2/3complex. The SH3 domain of
          myosin-I is required for myosin-I-induced actin
          polymerization. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 55

 Score = 32.4 bits (74), Expect = 0.019
 Identities = 16/57 (28%), Positives = 28/57 (49%), Gaps = 9/57 (15%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          +AL+D+      G  +  L     DI+++    D+ WW A+++    DE   G VP+
Sbjct: 3  KALYDFA-----GSVANELSLKKDDIVYIVQKEDNGWWLAKKL----DESKEGWVPA 50


>gnl|CDD|212757 cd11823, SH3_Nostrin, Src homology 3 domain of Nitric Oxide
          Synthase TRaffic INducer.  Nostrin is expressed in
          endothelial and epithelial cells and is involved in the
          regulation, trafficking and targeting of endothelial
          NOS (eNOS). It facilitates the endocytosis of eNOS by
          coordinating the functions of dynamin and the
          Wiskott-Aldrich syndrome protein (WASP). Increased
          expression of Nostrin may be correlated to
          preeclampsia. Nostrin contains an N-terminal F-BAR
          domain and a C-terminal SH3 domain. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 53

 Score = 32.3 bits (74), Expect = 0.019
 Identities = 13/39 (33%), Positives = 18/39 (46%), Gaps = 5/39 (12%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQ 59
          +AL+ Y   ++D L         GDI+ V    DD WW 
Sbjct: 3  KALYSYTANREDELS-----LQPGDIIEVHEKQDDGWWL 36


>gnl|CDD|212704 cd11770, SH3_Nephrocystin, Src Homology 3 domain of Nephrocystin
          (or Nephrocystin-1).  Nephrocystin contains an SH3
          domain involved in signaling pathways that regulate
          cell adhesion and cytoskeletal organization. It is a
          protein that in humans is associated with juvenile
          nephronophthisis, an inherited kidney disease
          characterized by renal fibrosis that lead to chronic
          renal failure in children. It is localized in cell-cell
          junctions in renal duct cells, and is known to interact
          with Ack1, an activated Cdc42-associated kinase. SH3
          domains are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 54

 Score = 32.3 bits (74), Expect = 0.020
 Identities = 12/39 (30%), Positives = 18/39 (46%), Gaps = 5/39 (12%)

Query: 39 LPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          L F  G++L + +   D WW A      G+    G+VP 
Sbjct: 16 LSFKKGEVLRIISKRADGWWLAEN--SKGNR---GLVPK 49


>gnl|CDD|212992 cd12059, SH3_MLK1-3, Src Homology 3 domain of Mixed Lineage
          Kinases 1, 2, and 3.  MLKs 1, 2, and 3 are
          Serine/Threonine Kinases (STKs), catalyzing the
          transfer of the gamma-phosphoryl group from ATP to S/T
          residues on protein substrates. MLKs act as
          mitogen-activated protein kinase kinase kinases
          (MAP3Ks, MKKKs, MAPKKKs), which phosphorylate and
          activate MAPK kinases (MAPKKs or MKKs or MAP2Ks), which
          in turn phosphorylate and activate MAPKs during
          signaling cascades that are important in mediating
          cellular responses to extracellular signals. MLKs play
          roles in immunity and inflammation, as well as in cell
          death, proliferation, and cell cycle regulation. Little
          is known about the specific function of MLK1, also
          called MAP3K9. It is capable of activating the c-Jun
          N-terminal kinase pathway. Mice lacking both MLK1 and
          MLK2 are viable, fertile, and have normal life spans.
          MLK2, also called MAP3K10, is abundant in brain,
          skeletal muscle, and testis. It functions upstream of
          the MAPK, c-Jun N-terminal kinase. It binds
          hippocalcin, a calcium-sensor protein that protects
          neurons against calcium-induced cell death. Both MLK2
          and hippocalcin may be associated with the pathogenesis
          of Parkinson's disease. MLK3, also called MAP3K11, is
          highly expressed in breast cancer cells and its
          signaling through c-Jun N-terminal kinase has been
          implicated in the migration, invasion, and malignancy
          of cancer cells. It also functions as a negative
          regulator of Inhibitor of Nuclear Factor-KappaB Kinase
          (IKK) and thus, impacts inflammation and immunity. MLKs
          contain an SH3 domain, a catalytic kinase domain, a
          leucine zipper, a proline-rich region, and a CRIB
          domain that mediates binding to GTP-bound Cdc42 and
          Rac. SH3 domains are protein interaction domains that
          bind to proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 58

 Score = 32.0 bits (73), Expect = 0.022
 Identities = 18/60 (30%), Positives = 27/60 (45%), Gaps = 14/60 (23%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHV----TNASDDEWWQARRVLPSGDEQGIGIVPS 77
          A+FDY+ + +D L  R      GD + V    +  S DE W   ++        +GI PS
Sbjct: 4  AVFDYEASAEDELTLR-----RGDRVEVLSKDSAVSGDEGWWTGKI-----NDRVGIFPS 53


>gnl|CDD|212751 cd11817, SH3_Eve1_4, Fourth Src homology 3 domain of ADAM-binding
          protein Eve-1.  Eve-1, also called SH3
          domain-containing protein 19 (SH3D19) or EEN-binding
          protein (EBP), exists in multiple alternatively spliced
          isoforms. The longest isoform contains five SH3 domain
          in the C-terminal region and seven proline-rich motifs
          in the N-terminal region. It is abundantly expressed in
          skeletal muscle and heart, and may be involved in
          regulating the activity of ADAMs (A disintegrin and
          metalloproteases). Eve-1 interacts with EEN, an
          endophilin involved in endocytosis and may be the
          target of the MLL-EEN fusion protein that is implicated
          in leukemogenesis. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 50

 Score = 31.7 bits (72), Expect = 0.024
 Identities = 20/57 (35%), Positives = 27/57 (47%), Gaps = 13/57 (22%)

Query: 22 ALFDYD-PTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          AL+D+   T++D      L F  GD + VT   D EW + R    +G E   GI P 
Sbjct: 4  ALYDFTGETEED------LSFQRGDRILVTEHLDAEWSRGRL---NGRE---GIFPR 48


>gnl|CDD|212938 cd12005, SH3_Lck, Src homology 3 domain of Lck Protein Tyrosine
          Kinase.  Lck is a member of the Src subfamily of
          proteins, which are cytoplasmic (or non-receptor) PTKs.
          Lck is expressed in T-cells and natural killer cells.
          It plays a critical role in T-cell maturation,
          activation, and T-cell receptor (TCR) signaling. Lck
          phosphorylates ITAM (immunoreceptor tyr activation
          motif) sequences on several subunits of TCRs, leading
          to the activation of different second messenger
          cascades. Phosphorylated ITAMs serve as binding sites
          for other signaling factor such as Syk and ZAP-70,
          leading to their activation and propagation of
          downstream events. In addition, Lck regulates
          drug-induced apoptosis by interfering with the
          mitochondrial death pathway. The apototic role of Lck
          is independent of its primary function in T-cell
          signaling. Src kinases contain an N-terminal SH4 domain
          with a myristoylation site, followed by SH3 and SH2
          domains, a tyr kinase domain, and a regulatory
          C-terminal region containing a conserved tyr. They are
          activated by autophosphorylation at the tyr kinase
          domain, but are negatively regulated by phosphorylation
          at the C-terminal tyr by Csk (C-terminal Src Kinase).
          The SH3 domain of Src kinases contributes to substrate
          recruitment by binding adaptor proteins/substrates, and
          regulation of kinase activity through an intramolecular
          interaction. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 54

 Score = 31.7 bits (72), Expect = 0.030
 Identities = 18/55 (32%), Positives = 27/55 (49%), Gaps = 10/55 (18%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVP 76
          AL+ Y+P+ D       L F  G+ L +      EWW+A+  L +G E   G +P
Sbjct: 4  ALYSYEPSHDG-----DLGFEKGEKLRILE-QSGEWWKAQS-LTTGQE---GFIP 48


>gnl|CDD|212839 cd11906, SH3_BTK, Src Homology 3 domain of Bruton's tyrosine
          kinase.  BTK is a cytoplasmic (or nonreceptor) tyr
          kinase containing Src homology protein interaction
          domains (SH3, SH2) N-terminal to the catalytic tyr
          kinase domain. It also contains an N-terminal
          pleckstrin homology (PH) domain, which binds the
          products of PI3K and allows membrane recruitment and
          activation, and the Tec homology (TH) domain with
          proline-rich and zinc-binding regions. Btk is expressed
          in B-cells, and a variety of myeloid cells including
          mast cells, platelets, neutrophils, and dendrictic
          cells. It interacts with a variety of partners, from
          cytosolic proteins to nuclear transcription factors,
          suggesting a diversity of functions. Stimulation of a
          diverse array of cell surface receptors, including
          antigen engagement of the B-cell receptor (BCR), leads
          to PH-mediated membrane translocation of Btk and
          subsequent phosphorylation by Src kinase and
          activation. Btk plays an important role in the life
          cycle of B-cells including their development,
          differentiation, proliferation, survival, and
          apoptosis. Mutations in Btk cause the primary
          immunodeficiency disease, X-linked agammaglobulinaemia
          (XLA) in humans. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 55

 Score = 31.7 bits (72), Expect = 0.031
 Identities = 18/58 (31%), Positives = 25/58 (43%), Gaps = 14/58 (24%)

Query: 22 ALFDYDP-TKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGI-GIVPS 77
          AL+DY P    D      L    G+   +   S+  WW+AR      D+ G  G +PS
Sbjct: 5  ALYDYTPMNAQD------LQLRKGEEYVILEESNLPWWRAR------DKNGREGYIPS 50


>gnl|CDD|212700 cd11766, SH3_Nck_2, Second Src Homology 3 domain of Nck adaptor
          proteins.  Nck adaptor proteins regulate actin
          cytoskeleton dynamics by linking proline-rich effector
          molecules to protein tyrosine kinases and
          phosphorylated signaling intermediates. They contain
          three SH3 domains and a C-terminal SH2 domain. They
          function downstream of the PDGFbeta receptor and are
          involved in Rho GTPase signaling and actin dynamics.
          Vertebrates contain two Nck adaptor proteins: Nck1
          (also called Nckalpha) and Nck2 (also called Nckbeta or
          Growth factor receptor-bound protein 4, Grb4), which
          show partly overlapping functions but also bind
          distinct targets. Their SH3 domains are involved in
          recruiting downstream effector molecules, such as the
          N-WASP/Arp2/3 complex, which when activated induces
          actin polymerization that results in the production of
          pedestals, or protrusions of the plasma membrane. The
          second SH3 domain of Nck appears to prefer ligands
          containing the APxxPxR motif. SH3 domains are protein
          interaction domains that usually bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially a PxxP motif. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 53

 Score = 31.5 bits (72), Expect = 0.034
 Identities = 12/41 (29%), Positives = 18/41 (43%), Gaps = 5/41 (12%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQAR 61
             F+Y+  ++D L  R      GD + V   S D WW+  
Sbjct: 3  VVKFNYEAQREDELSLRK-----GDRVLVLEKSSDGWWRGE 38


>gnl|CDD|212714 cd11780, SH3_Sorbs_3, Third (or C-terminal) Src Homology 3 domain
          of Sorbin and SH3 domain containing (Sorbs) proteins
          and similar domains.  This family, also called the
          vinexin family, is composed predominantly of adaptor
          proteins containing one sorbin homology (SoHo) and
          three SH3 domains. Members include the third SH3
          domains of Sorbs1 (or ponsin), Sorbs2 (or ArgBP2),
          Vinexin (or Sorbs3), and similar domains. They are
          involved in the regulation of cytoskeletal
          organization, cell adhesion, and growth factor
          signaling. Members of this family bind multiple
          partners including signaling molecules like c-Abl,
          c-Arg, Sos, and c-Cbl, as well as cytoskeletal
          molecules such as vinculin and afadin. They may have
          overlapping functions. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 55

 Score = 31.5 bits (72), Expect = 0.038
 Identities = 19/56 (33%), Positives = 24/56 (42%), Gaps = 9/56 (16%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVP 76
          RAL+ Y P  +D L  R      GDI++V    DD W+    V  S      G  P
Sbjct: 3  RALYSYTPQNEDELELRE-----GDIVYVMEKCDDGWF----VGTSERTGLFGTFP 49


>gnl|CDD|212783 cd11849, SH3_SPIN90, Src homology 3 domain of SH3 protein
          interacting with Nck, 90 kDa (SPIN90).  SPIN90 is also
          called NCK interacting protein with SH3 domain
          (NCKIPSD), Dia-interacting protein (DIP), 54 kDa
          vimentin-interacting protein (VIP54), or
          WASP-interacting SH3-domain protein (WISH). It is an
          F-actin binding protein that regulates actin
          polymerization and endocytosis. It associates with the
          Arp2/3 complex near actin filaments and determines
          filament localization at the leading edge of
          lamellipodia. SPIN90 is expressed in the early stages
          of neuronal differentiation and plays a role in
          regulating growth cone dynamics and neurite outgrowth.
          It also interacts with IRSp53 and regulates cell
          motility by playing a role in the formation of membrane
          protrusions. SPIN90 contains an N-terminal SH3 domain,
          a proline-rich domain, and a C-terminal VCA
          (verprolin-homology and cofilin-like acidic) domain.
          SH3 domains are protein interaction domains that bind
          to proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 53

 Score = 31.1 bits (71), Expect = 0.040
 Identities = 15/58 (25%), Positives = 23/58 (39%), Gaps = 10/58 (17%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSK 78
          RAL+D+   +        L F  G+   +   S+  WW       SG+    G VP+ 
Sbjct: 3  RALYDFKSAE-----PNTLSFSEGETFLLLERSNAHWWLVTNH--SGE---TGYVPAN 50


>gnl|CDD|212929 cd11996, SH3_Intersectin2_5, Fifth Src homology 3 domain (or
          SH3E) of Intersectin-2.  Intersectin-2 (ITSN2) is an
          adaptor protein that functions in exo- and endocytosis,
          actin cytoskeletal reorganization, and signal
          transduction. It plays a role in clathrin-coated pit
          (CCP) formation. It binds to many proteins through its
          multidomain structure and facilitate the assembly of
          multimeric complexes. ITSN2 also functions as a
          specific GEF for Cdc42 activation in epithelial
          morphogenesis, and is required in mitotic spindle
          orientation. It exists in alternatively spliced short
          and long isoforms. The short isoform contains two Eps15
          homology domains (EH1 and EH2), a coiled-coil region
          and five SH3 domains (SH3A-E), while the long isoform,
          in addition, contains RhoGEF (also called
          Dbl-homologous or DH), Pleckstrin homology (PH) and C2
          domains. The fifth SH3 domain (or SH3E) of ITSN2 is
          expected to bind protein partners, similar to ITSN1
          which has been shown to bind many protein partners
          including SGIP1, Sos1, dynamin1/2, CIN85, c-Cbl, SHIP2,
          N-WASP, and synaptojanin-1, among others. SH3 domains
          are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 54

 Score = 31.1 bits (70), Expect = 0.042
 Identities = 18/57 (31%), Positives = 28/57 (49%), Gaps = 13/57 (22%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGI-GIVPS 77
          A++DY    +D L      F  G +++V N  D +WWQ       G+  G+ G+ PS
Sbjct: 5  AMYDYTANNEDELS-----FSKGQLINVLNKDDPDWWQ-------GEINGVTGLFPS 49


>gnl|CDD|212865 cd11932, SH3_SH3RF2_2, Second Src Homology 3 domain of SH3 domain
          containing ring finger 2.  SH3RF2 is also called POSHER
          (POSH-eliminating RING protein) or HEPP1 (heart protein
          phosphatase 1-binding protein). It acts as an
          anti-apoptotic regulator of the JNK pathway by binding
          to and promoting the degradation of SH3RF1 (or POSH), a
          scaffold protein that is required for pro-apoptotic JNK
          activation. It may also play a role in cardiac
          functions together with protein phosphatase 1. SH3RF2
          contains an N-terminal RING finger domain and three SH3
          domains. This model represents the second SH3 domain,
          located C-terminal of the first SH3 domain at the
          N-terminal half, of SH3RF2. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 57

 Score = 31.3 bits (71), Expect = 0.045
 Identities = 16/53 (30%), Positives = 26/53 (49%), Gaps = 5/53 (9%)

Query: 21 RALFDYD-PTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGI 72
          RAL+++D   K+       L F   DI+ V +  D+ W + +     GD+ GI
Sbjct: 3  RALYNFDLKEKNREESKDCLKFQKDDIITVISRVDENWAEGKL----GDQVGI 51


>gnl|CDD|212774 cd11840, SH3_Intersectin_5, Fifth Src homology 3 domain (or SH3E)
          of Intersectin.  Intersectins (ITSNs) are adaptor
          proteins that function in exo- and endocytosis, actin
          cytoskeletal reorganization, and signal transduction.
          They are essential for initiating clathrin-coated pit
          formation. They bind to many proteins through their
          multidomain structure and facilitate the assembly of
          multimeric complexes. Vertebrates contain two ITSN
          proteins, ITSN1 and ITSN2, which exist in alternatively
          spliced short and long isoforms. The short isoforms
          contain two Eps15 homology domains (EH1 and EH2), a
          coiled-coil region and five SH3 domains (SH3A-E), while
          the long isoforms, in addition, contain RhoGEF (also
          called Dbl-homologous or DH), Pleckstrin homology (PH)
          and C2 domains. ITSN1 and ITSN2 are both widely
          expressed, with variations depending on tissue type and
          stage of development. The fifth SH3 domain (or SH3E) of
          ITSN1 has been shown to bind many protein partners
          including SGIP1, Sos1, dynamin1/2, CIN85, c-Cbl, SHIP2,
          N-WASP, and synaptojanin-1, among others. SH3 domains
          are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 53

 Score = 31.2 bits (71), Expect = 0.047
 Identities = 14/39 (35%), Positives = 20/39 (51%), Gaps = 5/39 (12%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQ 59
           ALF Y    +D L      F  GDI++V +  D +WW+
Sbjct: 3  IALFPYTAQNEDELS-----FQKGDIINVLSKDDPDWWR 36


>gnl|CDD|212989 cd12056, SH3_CD2AP_3, Third Src Homology 3 domain (SH3C) of
          CD2-associated protein.  CD2AP, also called CMS (Cas
          ligand with Multiple SH3 domains) or METS1
          (Mesenchyme-to-Epithelium Transition protein with SH3
          domains), is a cytosolic adaptor protein that plays a
          role in regulating the cytoskeleton. It is critical in
          cell-to-cell union necessary for kidney function. It
          also stabilizes the contact between a T cell and
          antigen-presenting cells. It is primarily expressed in
          podocytes at the cytoplasmic face of the slit diaphragm
          and serves as a linker anchoring podocin and nephrin to
          the actin cytoskeleton. CD2AP contains three SH3
          domains, a proline-rich region, and a C-terminal
          coiled-coil domain. All of these domains enable CD2AP
          to bind various protein partners and assemble complexes
          that have been implicated in many different functions.
          This alignment model represents the third SH3 domain
          (SH3C) of CD2AP. SH3C has been shown to bind ubiquitin.
          SH3 domains are protein interaction domains that bind
          to proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 57

 Score = 31.3 bits (71), Expect = 0.048
 Identities = 12/43 (27%), Positives = 22/43 (51%), Gaps = 7/43 (16%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVT--NASDDEWWQ 59
          + +ALF Y+ T +D      L F  G+I+ +   +  +  WW+
Sbjct: 3  YCKALFHYEGTNED-----ELDFKEGEIILIISKDTGEPGWWK 40


>gnl|CDD|213018 cd12142, SH3_D21-like, Src Homology 3 domain of SH3
          domain-containing protein 21 (SH3D21) and similar
          proteins.  N-terminal SH3 domain of the uncharacterized
          protein SH3 domain-containing protein 21, and similar
          uncharacterized domains, it belongs to the CD2AP-like_3
          subfamily of proteins. The CD2AP-like_3 subfamily is
          composed of the third SH3 domain (SH3C) of CD2AP, CIN85
          (Cbl-interacting protein of 85 kDa), and similar
          domains. CD2AP and CIN85 are adaptor proteins that bind
          to protein partners and assemble complexes that have
          been implicated in T cell activation, kidney function,
          and apoptosis of neuronal cells. They also associate
          with endocytic proteins, actin cytoskeleton components,
          and other adaptor proteins involved in receptor
          tyrosine kinase (RTK) signaling. CD2AP and the main
          isoform of CIN85 contain three SH3 domains, a
          proline-rich region, and a C-terminal coiled-coil
          domain. All of these domains enable CD2AP and CIN85 to
          bind various protein partners and assemble complexes
          that have been implicated in many different functions.
          SH3C of both proteins have been shown to bind to
          ubiquitin. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 55

 Score = 31.3 bits (71), Expect = 0.048
 Identities = 14/41 (34%), Positives = 21/41 (51%), Gaps = 7/41 (17%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNAS--DDEWWQ 59
          R LFDY+P   D L  +      GD++ V +    D+ WW+
Sbjct: 3  RVLFDYNPVAPDELALK-----KGDVIEVISKETEDEGWWE 38


>gnl|CDD|212961 cd12028, SH3_ZO-3, Src homology 3 domain of the Tight junction
          protein, Zonula occludens protein 3.  ZO-3 is a
          scaffolding protein that associates with other ZO
          proteins and other proteins of the tight junction,
          zonula adherens, and gap junctions. ZO proteins play
          roles in regulating cytoskeletal dynamics at these cell
          junctions. ZO-3 is critical for epidermal barrier
          function. It regulates cyclin D1-dependent cell
          proliferation. It is considered a member of the MAGUK
          (membrane-associated guanylate kinase) protein family,
          which is characterized by the presence of a core of
          three domains: PDZ, SH3, and guanylate kinase (GuK).
          The GuK domain in MAGUK proteins is enzymatically
          inactive; instead, the domain mediates protein-protein
          interactions and associates intramolecularly with the
          SH3 domain. The C-terminal region of ZO-3 is the
          smallest of the three ZO proteins. The SH3 domain of
          the related protein ZO-1 has been shown to bind ZONAB,
          ZAK, afadin, and Galpha12. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 65

 Score = 31.4 bits (71), Expect = 0.048
 Identities = 22/63 (34%), Positives = 29/63 (46%), Gaps = 4/63 (6%)

Query: 21 RALFDYDPTKDDGLP-SRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSKK 79
          R  FDY+P    GL  +RG  FH  D +H         W A R+     E   GI+P++ 
Sbjct: 6  RTHFDYEPDPPSGLSFTRGEVFHVLDTMHRGKLGS---WLAVRMGRDLREMEKGIIPNQS 62

Query: 80 RWE 82
          R E
Sbjct: 63 RAE 65


>gnl|CDD|212890 cd11957, SH3_RUSC2, Src homology 3 domain of RUN and SH3
          domain-containing protein 2.  RUSC2, also called Iporin
          or Interacting protein of Rab1, is expressed
          ubiquitously with highest amounts in the brain and
          testis. It interacts with the small GTPase Rab1 and the
          Golgi matrix protein GM130, and may function in linking
          GTPases to certain intracellular signaling pathways.
          RUSC proteins are adaptor proteins consisting of RUN,
          leucine zipper, and SH3 domains. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 52

 Score = 31.0 bits (70), Expect = 0.051
 Identities = 13/38 (34%), Positives = 20/38 (52%), Gaps = 6/38 (15%)

Query: 39 LPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVP 76
          L F+ GDIL V + +D +W +       G +   G+VP
Sbjct: 16 LSFNKGDILQVLSRADGDWLRCSL----GPDS--GLVP 47


>gnl|CDD|213019 cd12143, SH3_ARHGAP9, Src Homology 3 domain of Rho
          GTPase-activating protein 9 and similar proteins.  Rho
          GTPase-activating proteins (RhoGAPs or ARHGAPs) bind to
          Rho proteins and enhance the hydrolysis rates of bound
          GTP. ARHGAP9 functions as a GAP for Rac and Cdc42, but
          not for RhoA. It negatively regulates cell migration
          and adhesion. It also acts as a docking protein for the
          MAP kinases Erk2 and p38alpha, and may facilitate
          cross-talk between the Rho GTPase and MAPK pathways to
          control actin remodeling. It contains SH3, WW,
          Pleckstin homology (PH), and RhoGAP domains. SH3
          domains bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs; they play a role in the regulation of enzymes
          by intramolecular interactions, changing the
          subcellular localization of signal pathway components
          and mediate multiprotein complex assemblies.
          Length = 57

 Score = 31.0 bits (70), Expect = 0.051
 Identities = 13/42 (30%), Positives = 21/42 (50%), Gaps = 3/42 (7%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRV 63
          AL+ Y  T  DG   R +    G+   +   ++ +WWQ RR+
Sbjct: 4  ALYAYQYTGADG---RQVSIAEGERFLLLRKTNSDWWQVRRL 42


>gnl|CDD|212763 cd11829, SH3_GAS7, Src homology 3 domain of Growth Arrest
          Specific protein 7.  GAS7 is mainly expressed in the
          brain and is required for neurite outgrowth. It may
          also play a role in the protection and migration of
          embryonic stem cells. Treatment-related acute myeloid
          leukemia (AML) has been reported resulting from
          mixed-lineage leukemia (MLL)-GAS7 translocations as a
          complication of primary cancer treatment. GAS7 contains
          an N-terminal SH3 domain, followed by a WW domain, and
          a central F-BAR domain. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 52

 Score = 30.6 bits (69), Expect = 0.062
 Identities = 11/44 (25%), Positives = 20/44 (45%), Gaps = 4/44 (9%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARR 62
            R L+ +   +      +GL F  G+++ V  A D  WW+  +
Sbjct: 1  LCRTLYAFTGEQHQ----QGLSFEAGELIRVLQAPDGGWWEGEK 40


>gnl|CDD|212740 cd11806, SH3_PRMT2, Src homology 3 domain of Protein arginine
          N-methyltransferase 2.  PRMT2, also called HRMT1L1,
          belongs to the arginine methyltransferase protein
          family. It functions as a coactivator to both estrogen
          receptor alpha (ER-alpha) and androgen receptor (AR),
          presumably through arginine methylation. The ER-alpha
          transcription factor is involved in cell proliferation,
          differentiation, morphogenesis, and apoptosis, and is
          also implicated in the development and progression of
          breast cancer. PRMT2 and its variants are upregulated
          in breast cancer cells and may be involved in
          modulating the ER-alpha signaling pathway during
          formation of breast cancer. PRMT2 also plays a role in
          regulating the function of E2F transcription factors,
          which are critical cell cycle regulators, by binding to
          the retinoblastoma gene product (RB). It contains an
          N-terminal SH3 domain and an AdoMet binding domain. SH3
          domains are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 53

 Score = 30.8 bits (70), Expect = 0.064
 Identities = 13/41 (31%), Positives = 16/41 (39%), Gaps = 5/41 (12%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARR 62
          A+ D+  T D  L      F  GD L V      +WW A  
Sbjct: 4  AIADFVATDDSQLS-----FESGDKLLVLRKPSVDWWWAEH 39


>gnl|CDD|212887 cd11954, SH3_ASPP1, Src Homology 3 domain of Apoptosis
          Stimulating of p53 protein 1.  ASPP1, like ASPP2,
          activates the apoptotic function of the p53 family of
          tumor suppressors (p53, p63, and p73). In addition, it
          functions in the cytoplasm to regulate the nuclear
          localization of the transcriptional cofactors YAP and
          TAZ by inihibiting their phosphorylation; YAP and TAZ
          are important regulators of cell expansion,
          differentiation, migration, and invasion. ASPP1 is
          downregulated in breast tumors expressing wild-type
          p53. It contains a proline-rich region, four ankyrin
          (ANK) repeats, and an SH3 domain at its C-terminal
          half. The SH3 domain and the ANK repeats of ASPP1
          contribute to the p53 binding site; they bind to the
          DNA binding domain of p53. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 57

 Score = 30.4 bits (68), Expect = 0.087
 Identities = 18/53 (33%), Positives = 24/53 (45%), Gaps = 12/53 (22%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDD---EWWQARRVLPSGDEQG 71
          AL+DY+    D L      F  GD + +    DD   EWW AR      D++G
Sbjct: 5  ALWDYEAQNADELS-----FQEGDAITILRRKDDSETEWWWARL----NDKEG 48


>gnl|CDD|212807 cd11874, SH3_CD2AP-like_2, Second Src Homology 3 domain (SH3B) of
          CD2-associated protein and similar proteins.  This
          subfamily is composed of the second SH3 domain (SH3B)
          of CD2AP, CIN85 (Cbl-interacting protein of 85 kDa),
          and similar domains. CD2AP and CIN85 are adaptor
          proteins that bind to protein partners and assemble
          complexes that have been implicated in T cell
          activation, kidney function, and apoptosis of neuronal
          cells. They also associate with endocytic proteins,
          actin cytoskeleton components, and other adaptor
          proteins involved in receptor tyrosine kinase (RTK)
          signaling. CD2AP and the main isoform of CIN85 contain
          three SH3 domains, a proline-rich region, and a
          C-terminal coiled-coil domain. All of these domains
          enable CD2AP and CIN85 to bind various protein partners
          and assemble complexes that have been implicated in
          many different functions. SH3B of both proteins have
          been shown to bind to Cbl. In the case of CD2AP, its
          SH3B binds to Cbl at a site distinct from the
          c-Cbl/SH3A binding site. The CIN85 SH3B also binds
          ubiquitin. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 53

 Score = 30.0 bits (68), Expect = 0.10
 Identities = 15/51 (29%), Positives = 22/51 (43%), Gaps = 10/51 (19%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARR-----VLPS 66
          + LF Y P  +D L    L    GD + V    ++ WW+ +      V PS
Sbjct: 3  KVLFSYTPQNEDEL---ELKV--GDTIEVLGEVEEGWWEGKLNGKVGVFPS 48


>gnl|CDD|212907 cd11974, SH3_ASEF2, Src homology 3 domain of APC-Stimulated
          guanine nucleotide Exchange Factor 2.  ASEF2, also
          called Spermatogenesis-associated protein 13 (SPATA13),
          is a GEF that localizes with actin at the leading edge
          of cells and is important in cell migration and
          adhesion dynamics. GEFs activate small GTPases by
          exchanging bound GDP for free GTP. ASEF2 can activate
          both Rac 1 and Cdc42, but only Rac1 activation is
          necessary for increased cell migration and adhesion
          turnover. Together with APC (adenomatous polyposis
          coli) and Neurabin2, a scaffold protein that binds
          F-actin, it is involved in regulating HGF-induced cell
          migration. ASEF2 contains a SH3 domain followed by
          RhoGEF (also called Dbl-homologous or DH) and
          Pleckstrin Homology (PH) domains. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 54

 Score = 30.0 bits (67), Expect = 0.11
 Identities = 16/43 (37%), Positives = 25/43 (58%), Gaps = 5/43 (11%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQAR 61
          ++ AL+D+  T DD    + L F  GD++ V  AS+ +WW  R
Sbjct: 2  YAEALWDH-VTMDD----QELAFKAGDVIRVLEASNKDWWWGR 39


>gnl|CDD|212746 cd11812, SH3_AHI-1, Src Homology 3 domain of Abelson helper
          integration site-1 (AHI-1).  AHI-1, also called
          Jouberin, is expressed in high levels in the brain,
          gonad tissues, and skeletal muscle. It is an adaptor
          protein that interacts with the small GTPase Rab8a and
          regulates it distribution and function, affecting
          cilium formation and vesicle transport. Mutations in
          the AHI-1 gene can cause Joubert syndrome, a disorder
          characterized by brainstem malformations, cerebellar
          aplasia/hypoplasia, and retinal dystrophy. AHI-1
          variation is also associated with susceptibility to
          schizophrenia and type 2 diabetes mellitus progression.
          AHI-1 contains WD40 and SH3 domains. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 52

 Score = 29.8 bits (67), Expect = 0.12
 Identities = 15/42 (35%), Positives = 19/42 (45%), Gaps = 5/42 (11%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRV 63
          AL+DY   + D L       H GDI+ V    +D WW    V
Sbjct: 4  ALYDYTANRSDELT-----IHRGDIIRVLYKDNDNWWFGSLV 40


>gnl|CDD|212710 cd11776, SH3_PI3K_p85, Src Homology 3 domain of the p85
          regulatory subunit of Class IA Phosphatidylinositol
          3-kinases.  Class I PI3Ks convert PtdIns(4,5)P2 to the
          critical second messenger PtdIns(3,4,5)P3. They are
          heterodimers and exist in multiple isoforms consisting
          of one catalytic subunit (out of four isoforms) and one
          of several regulatory subunits. Class IA PI3Ks
          associate with the p85 regulatory subunit family, which
          contains SH3, RhoGAP, and SH2 domains. The p85 subunits
          recruit the PI3K p110 catalytic subunit to the
          membrane, where p110 phosphorylates inositol lipids.
          Vertebrates harbor two p85 isoforms, called alpha and
          beta. SH3 domains are protein interaction domains that
          bind to proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 72

 Score = 30.6 bits (69), Expect = 0.12
 Identities = 19/72 (26%), Positives = 30/72 (41%), Gaps = 16/72 (22%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSKKR 80
          RAL+DY+  +D+      +    GD+L V N           +L  G   G   VP  + 
Sbjct: 4  RALYDYEKERDE-----DIILKTGDVLVVENPE---------LLALGVPDGKETVPKPEG 49

Query: 81 W--ERKQRARDR 90
          W   + +R  +R
Sbjct: 50 WLEGKNERTGER 61


>gnl|CDD|212790 cd11856, SH3_p47phox_like, Src homology 3 domains of the p47phox
          subunit of NADPH oxidase and similar domains.  This
          family is composed of the tandem SH3 domains of p47phox
          subunit of NADPH oxidase and Nox Organizing protein 1
          (NoxO1), the four SH3 domains of Tks4 (Tyr kinase
          substrate with four SH3 domains), the five SH3 domains
          of Tks5, the SH3 domain of obscurin, Myosin-I,  and
          similar domains. Most members of this group also
          contain Phox homology (PX) domains, except for obscurin
          and Myosin-I. p47phox and NoxO1 are regulators of the
          phagocytic NADPH oxidase complex (also called Nox2 or
          gp91phox) and nonphagocytic NADPH oxidase Nox1,
          respectively. They play roles in the activation of
          their respective NADPH oxidase, which catalyzes the
          transfer of electrons from NADPH to molecular oxygen to
          form superoxide. Tks proteins are Src substrates and
          scaffolding proteins that play important roles in the
          formation of podosomes and invadopodia, the dynamic
          actin-rich structures that are related to cell
          migration and cancer cell invasion. Obscurin is a giant
          muscle protein that plays important roles in the
          organization and assembly of the myofibril and the
          sarcoplasmic reticulum. Type I myosins (Myosin-I) are
          actin-dependent motors in endocytic actin structures
          and actin patches. They play roles in membrane traffic
          in endocytic and secretory pathways, cell motility, and
          mechanosensing. Myosin-I contains an N-terminal
          actin-activated ATPase, a phospholipid-binding TH1
          (tail homology 1) domain, and a C-terminal extension
          which includes an F-actin-binding TH2 domain, an SH3
          domain, and an acidic peptide that participates in
          activating the Arp2/3complex. The SH3 domain of
          myosin-I is required for myosin-I-induced actin
          polymerization. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 53

 Score = 29.9 bits (68), Expect = 0.13
 Identities = 14/51 (27%), Positives = 24/51 (47%), Gaps = 9/51 (17%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQG 71
           A+ DY+   DD +         G+++ V   +D  WW  R+    GD++G
Sbjct: 3  VAIADYEAQGDDEIS-----LQEGEVVEVLEKNDSGWWYVRK----GDKEG 44


>gnl|CDD|212822 cd11889, SH3_Cyk3p-like, Src Homology 3 domain of Cytokinesis
          protein 3 and similar proteins.  Cytokinesis protein 3
          (Cyk3 or Cyk3p) is a component of the actomyosin ring
          independent cytokinesis pathway in yeast. It interacts
          with Inn1 and facilitates its recruitment to the bud
          neck, thereby promoting cytokinesis. Cyk3p contains an
          N-terminal SH3 domain and a C-terminal
          transglutaminase-like domain. The Cyk3p SH3 domain
          binds to the C-terminal proline-rich region of Inn1.
          SH3 domains bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs; they play a role in the regulation of enzymes
          by intramolecular interactions, changing the
          subcellular localization of signal pathway components
          and mediate multiprotein complex assemblies.
          Length = 53

 Score = 29.8 bits (67), Expect = 0.15
 Identities = 9/29 (31%), Positives = 13/29 (44%)

Query: 33 GLPSRGLPFHYGDILHVTNASDDEWWQAR 61
          G     L F  GD++ V +  D  WW  +
Sbjct: 10 GETEGDLGFLEGDLIEVLSIGDGSWWSGK 38


>gnl|CDD|212908 cd11975, SH3_ARHGEF9, Src homology 3 domain of the Rho guanine
          nucleotide exchange factor ARHGEF9.  ARHGEF9, also
          called PEM2 or collybistin, selectively activates Cdc42
          by exchanging bound GDP for free GTP. It is highly
          expressed in the brain and it interacts with gephyrin,
          a postsynaptic protein associated with GABA and glycine
          receptors. Mutations in the ARHGEF9 gene cause X-linked
          mental retardation with associated features like
          seizures, hyper-anxiety, aggressive behavior, and
          sensory hyperarousal. ARHGEF9 contains a SH3 domain
          followed by RhoGEF (also called Dbl-homologous or DH)
          and Pleckstrin Homology (PH) domains. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 62

 Score = 29.7 bits (66), Expect = 0.17
 Identities = 10/25 (40%), Positives = 17/25 (68%)

Query: 34 LPSRGLPFHYGDILHVTNASDDEWW 58
          + +R L F  GD++ V +AS+ +WW
Sbjct: 16 MANRELAFKAGDVIKVLDASNKDWW 40


>gnl|CDD|212761 cd11827, SH3_MyoIe_If_like, Src homology 3 domain of Myosins Ie,
          If, and similar proteins.  Myosins Ie (MyoIe) and If
          (MyoIf) are nonmuscle, unconventional, long tailed,
          class I myosins containing an N-terminal motor domain
          and a myosin tail with TH1, TH2, and SH3 domains. MyoIe
          interacts with the endocytic proteins, dynamin and
          synaptojanin-1, through its SH3 domain; it may play a
          role in clathrin-dependent endocytosis. In the kidney,
          MyoIe is critical for podocyte function and normal
          glomerular filtration. Mutations in MyoIe is associated
          with focal segmental glomerulosclerosis, a disease
          characterized by massive proteinuria and progression to
          end-stage kidney disease. MyoIf is predominantly
          expressed in the immune system; it plays a role in
          immune cell motility and innate immunity. Mutations in
          MyoIf may be associated with the loss of hearing. The
          MyoIf gene has also been found to be fused to the MLL
          (Mixed lineage leukemia) gene in infant acute myeloid
          leukemias (AML). SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 53

 Score = 29.3 bits (66), Expect = 0.18
 Identities = 13/41 (31%), Positives = 18/41 (43%), Gaps = 5/41 (12%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQAR 61
          +AL+ YD    D L      F+ GDI+ +       WW  R
Sbjct: 3  KALYAYDAQDTDELS-----FNEGDIIEILKEDPSGWWTGR 38


>gnl|CDD|212744 cd11810, SH3_RUSC1_like, Src homology 3 domain of RUN and SH3
          domain-containing proteins 1 and 2.  RUSC1 and RUSC2,
          that were originally characterized in silico. They are
          adaptor proteins consisting of RUN, leucine zipper, and
          SH3 domains. RUSC1, also called NESCA (New molecule
          containing SH3 at the carboxy-terminus), is highly
          expressed in the brain and is translocated to the
          nuclear membrane from the cytoplasm upon stimulation
          with neurotrophin. It plays a role in facilitating
          neurotrophin-dependent neurite outgrowth. It also
          interacts with NEMO (or IKKgamma) and may function in
          NEMO-mediated activation of NF-kB. RUSC2, also called
          Iporin, is expressed ubiquitously with highest amounts
          in the brain and testis. It interacts with the small
          GTPase Rab1 and the Golgi matrix protein GM130, and may
          function in linking GTPases to certain intracellular
          signaling pathways. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 50

 Score = 28.9 bits (65), Expect = 0.22
 Identities = 14/37 (37%), Positives = 16/37 (43%), Gaps = 5/37 (13%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEW 57
          RAL  +  T    L      F  GDIL V    DD+W
Sbjct: 3  RALCHHVATDSGQLS-----FRKGDILRVIARVDDDW 34


>gnl|CDD|212808 cd11875, SH3_CD2AP-like_3, Third Src Homology 3 domain (SH3C) of
          CD2-associated protein and similar proteins.  This
          subfamily is composed of the third SH3 domain (SH3C) of
          CD2AP, CIN85 (Cbl-interacting protein of 85 kDa), and
          similar domains. CD2AP and CIN85 are adaptor proteins
          that bind to protein partners and assemble complexes
          that have been implicated in T cell activation, kidney
          function, and apoptosis of neuronal cells. They also
          associate with endocytic proteins, actin cytoskeleton
          components, and other adaptor proteins involved in
          receptor tyrosine kinase (RTK) signaling. CD2AP and the
          main isoform of CIN85 contain three SH3 domains, a
          proline-rich region, and a C-terminal coiled-coil
          domain. All of these domains enable CD2AP and CIN85 to
          bind various protein partners and assemble complexes
          that have been implicated in many different functions.
          SH3C of both proteins have been shown to bind to
          ubiquitin. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 55

 Score = 29.2 bits (66), Expect = 0.25
 Identities = 14/41 (34%), Positives = 20/41 (48%), Gaps = 7/41 (17%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTN--ASDDEWWQ 59
          R LFDY+   +D L  R      GDI+ + +    D  WW+
Sbjct: 3  RVLFDYEAENEDELTLR-----EGDIVTILSKDCEDKGWWK 38


>gnl|CDD|212904 cd11971, SH3_Abi1, Src homology 3 domain of Abl Interactor 1.
          Abi1, also called e3B1, is a central regulator of actin
          cytoskeletal reorganization through interactions with
          many protein complexes. It is part of WAVE, a
          nucleation-promoting factor complex, that links Rac 1
          activation to actin polymerization causing lamellipodia
          protrusion at the plasma membrane. Abi1 interact with
          formins to promote protrusions at the leading edge of
          motile cells. It also is a target of alpha4 integrin,
          regulating membrane protrusions at sites of integrin
          engagement. Abi proteins are adaptor proteins serving
          as binding partners and substrates of Abl tyrosine
          kinases. They are involved in regulating actin
          cytoskeletal reorganization and play important roles in
          membrane-ruffling, endocytosis, cell motility, and cell
          migration. Abi proteins contain a homeobox homology
          domain, a proline-rich region, and a SH3 domain. The
          SH3 domain of Abi binds to a PxxP motif in Abl. SH3
          domains are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 59

 Score = 29.2 bits (65), Expect = 0.25
 Identities = 14/39 (35%), Positives = 21/39 (53%), Gaps = 5/39 (12%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQA 60
          A++DY   KDD L      F  G I++V   +DD W++ 
Sbjct: 4  AIYDYSKDKDDELS-----FMEGAIIYVIKKNDDGWYEG 37


>gnl|CDD|212946 cd12013, SH3_RIM-BP_3, Third Src homology 3 domain of
          Rab3-interacting molecules (RIMs) binding proteins.
          RIMs binding proteins (RBPs, RIM-BPs) associate with
          calcium channels present in photoreceptors, neurons,
          and hair cells; they interact simultaneously with
          specific calcium channel subunits, and active zone
          proteins, RIM1 and RIM2. RIMs are part of the matrix at
          the presynaptic active zone and are associated with
          synaptic vesicles through their interaction with the
          small GTPase Rab3. RIM-BPs play a role in regulating
          synaptic transmission by serving as adaptors and
          linking calcium channels with the synaptic vesicle
          release machinery. RIM-BPs contain three SH3 domains
          and two to three fibronectin III repeats. Invertebrates
          contain one, while vertebrates contain at least two
          RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called
          peripheral-type benzodiazapine receptor associated
          protein 1 (PRAX-1). Mammals contain a third protein,
          RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly
          expressed in the brain where they display overlapping
          but distinct expression patterns, while RIM-BP3 is
          almost exclusively expressed in the testis and is
          essential in spermiogenesis. The SH3 domains of RIM-BPs
          bind to the PxxP motifs of RIM1, RIM2, and L-type
          (alpha1D) and N-type (alpha1B) calcium channel
          subunits. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 61

 Score = 29.3 bits (66), Expect = 0.27
 Identities = 14/38 (36%), Positives = 18/38 (47%), Gaps = 2/38 (5%)

Query: 21 RALFDYDPTKDDGLP--SRGLPFHYGDILHVTNASDDE 56
           ALFDYDP +          L F  GDI+ V    D++
Sbjct: 3  VALFDYDPRESSPNVDAEVELSFRAGDIITVFGEMDED 40


>gnl|CDD|212767 cd11833, SH3_Stac_1, First C-terminal Src homology 3 domain of
          SH3 and cysteine-rich domain-containing (Stac)
          proteins.  Stac proteins are putative adaptor proteins
          that contain a cysteine-rich C1 domain and one or two
          SH3 domains at the C-terminus. There are three
          mammalian members (Stac1, Stac2, and Stac3) of this
          family. Stac1 and Stac3 contain two SH3 domains while
          Stac2 contains a single SH3 domain at the C-terminus.
          This model represents the first C-terminal SH3 domain
          of Stac1 and Stac3, and the single C-terminal SH3
          domain of Stac2. Stac1 and Stac2 have been found to be
          expressed differently in mature dorsal root ganglia
          (DRG) neurons. Stac1 is mainly expressed in peptidergic
          neurons while Stac2 is found in a subset of
          nonpeptidergic and all trkB+ neurons. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 53

 Score = 28.6 bits (64), Expect = 0.33
 Identities = 13/57 (22%), Positives = 28/57 (49%), Gaps = 11/57 (19%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSK 78
          AL+ + P +++ L  R      GD + + + S+++WW+ +       E  +G  P+ 
Sbjct: 4  ALYKFKPQENEDLEMRP-----GDKITLLDDSNEDWWKGKI------EDRVGFFPAN 49


>gnl|CDD|212889 cd11956, SH3_srGAP4, Src homology 3 domain of Slit-Robo GTPase
          Activating Protein 4.  srGAP4, also called ARHGAP4, is
          highly expressed in hematopoietic cells and may play a
          role in lymphocyte differentiation. It is able to
          stimulate the GTPase activity of Rac1, Cdc42, and RhoA.
          In the nervous system, srGAP4 has been detected in
          differentiating neurites and may be involved in axon
          and dendritic growth. srGAPs are Rho GAPs that interact
          with Robo1, the transmembrane receptor of Slit
          proteins. Slit proteins are secreted proteins that
          control axon guidance and the migration of neurons and
          leukocytes. srGAPs contain an N-terminal F-BAR domain,
          a Rho GAP domain, and a C-terminal SH3 domain. SH3
          domains are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 55

 Score = 28.7 bits (64), Expect = 0.40
 Identities = 17/58 (29%), Positives = 29/58 (50%), Gaps = 13/58 (22%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGI-GIVPSK 78
          A FDY      G  ++ L F  GD+L + + +  +WW+       G+  G+ G++P K
Sbjct: 6  ACFDYT-----GRTAQELSFKRGDVLLLHSKASSDWWR-------GEHNGMRGLIPHK 51


>gnl|CDD|212691 cd11757, SH3_SH3BP4, Src Homology 3 domain of SH3 domain-binding
          protein 4.  SH3 domain-binding protein 4 (SH3BP4) is
          also called transferrin receptor trafficking protein
          (TTP). SH3BP4 is an endocytic accessory protein that
          interacts with endocytic proteins including clathrin
          and dynamin, and regulates the internalization of the
          transferrin receptor (TfR). SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 52

 Score = 28.4 bits (63), Expect = 0.42
 Identities = 19/56 (33%), Positives = 25/56 (44%), Gaps = 11/56 (19%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          A+ DY PT         L F  GD L+V + S  EWW A       +   +G +PS
Sbjct: 4  AIKDYCPTN-----FTTLKFSKGDHLYVLDTSGGEWWYAH------NTTEMGYIPS 48


>gnl|CDD|212742 cd11808, SH3_Alpha_Spectrin, Src homology 3 domain of Alpha
          Spectrin.  Spectrin is a major structural component of
          the red blood cell membrane skeleton and is important
          in erythropoiesis and membrane biogenesis. It is a
          flexible, rope-like molecule composed of two subunits,
          alpha and beta, which consist of many spectrin-type
          repeats. Alpha and beta spectrin associate to form
          heterodimers and tetramers; spectrin tetramer formation
          is critical for red cell shape and deformability.
          Defects in alpha spectrin have been associated with
          inherited hemolytic anemias including hereditary
          spherocytosis (HSp), hereditary elliptocytosis (HE),
          and hereditary pyropoikilocytosis (HPP). Alpha spectrin
          contains a middle SH3 domain and a C-terminal EF-hand
          binding motif in addition to multiple spectrin repeats.
          SH3 domains are protein interaction domains that bind
          to proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 53

 Score = 28.2 bits (63), Expect = 0.43
 Identities = 16/50 (32%), Positives = 24/50 (48%), Gaps = 9/50 (18%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQG 71
          AL+DY          R +    GDIL + N+S+ +WW+    +   D QG
Sbjct: 4  ALYDYQEKS-----PREVSMKKGDILTLLNSSNKDWWK----VEVNDRQG 44


>gnl|CDD|212905 cd11972, SH3_Abi2, Src homology 3 domain of Abl Interactor 2.
          Abi2 is highly expressed in the brain and eye. It
          regulates actin cytoskeletal reorganization at adherens
          junctions and dendritic spines, which is important in
          cell morphogenesis, migration, and cognitive function.
          Mice deficient with Abi2 show defects in orientation
          and migration of lens fibers, neuronal migration,
          dendritic spine morphology, as well as deficits in
          learning and memory. Abi proteins are adaptor proteins
          serving as binding partners and substrates of Abl
          tyrosine kinases. They are involved in regulating actin
          cytoskeletal reorganization and play important roles in
          membrane-ruffling, endocytosis, cell motility, and cell
          migration. Abi proteins contain a homeobox homology
          domain, a proline-rich region, and a SH3 domain. The
          SH3 domain of Abi binds to a PxxP motif in Abl. SH3
          domains are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 61

 Score = 28.4 bits (63), Expect = 0.52
 Identities = 13/39 (33%), Positives = 21/39 (53%), Gaps = 5/39 (12%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQA 60
          A++DY   K+D L      F  G I++V   +DD W++ 
Sbjct: 7  AIYDYTKDKEDELS-----FQEGAIIYVIKKNDDGWYEG 40


>gnl|CDD|212827 cd11894, SH3_FCHSD2_2, Second Src Homology 3 domain of FCH and
          double SH3 domains protein 2.  FCHSD2 has a domain
          structure consisting of an N-terminal F-BAR (FES-CIP4
          Homology and Bin/Amphiphysin/Rvs), two SH3, and
          C-terminal proline-rich domains. It has only been
          characterized in silico and its function is unknown.
          SH3 domains are protein interaction domains that bind
          to proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 56

 Score = 28.4 bits (63), Expect = 0.55
 Identities = 21/63 (33%), Positives = 30/63 (47%), Gaps = 16/63 (25%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHV---TNASDDEWWQARRVLPSGDEQG-IGI 74
          F +AL+DY+   DD      L F  G I+ +    N  DD +W+       G+  G IG+
Sbjct: 1  FVKALYDYEGQTDD-----ELSFPEGAIIRILNKENQDDDGFWE-------GEFNGRIGV 48

Query: 75 VPS 77
           PS
Sbjct: 49 FPS 51


>gnl|CDD|212894 cd11961, SH3_Abp1_fungi_C2, Second C-terminal Src homology 3
          domain of Fungal Actin-binding protein 1.  Abp1 is an
          adaptor protein that functions in receptor-mediated
          endocytosis and vesicle trafficking. It contains an
          N-terminal actin-binding module, the
          actin-depolymerizing factor (ADF) homology domain, a
          central proline-rich region, and a C-terminal SH3
          domain (many yeast Abp1 proteins contain two C-terminal
          SH3 domains). Yeast Abp1 also contains two acidic
          domains that bind directly to the Arp2/3 complex, which
          is required to initiate actin polymerization. The SH3
          domain of yeast Abp1 binds and localizes the kinases,
          Ark1p and Prk1p, which facilitate actin patch
          disassembly following vesicle internalization. It also
          mediates the localization to the actin patch of the
          synaptojanin-like protein, Sjl2p, which plays a key
          role in endocytosis. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 53

 Score = 27.9 bits (62), Expect = 0.58
 Identities = 13/38 (34%), Positives = 19/38 (50%), Gaps = 5/38 (13%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWW 58
          +AL+DYD  +D+ L      F   D +      DD+WW
Sbjct: 3  KALYDYDAAEDNELS-----FFENDKIINIEFVDDDWW 35


>gnl|CDD|212806 cd11873, SH3_CD2AP-like_1, First Src Homology 3 domain (SH3A) of
          CD2-associated protein and similar proteins.  This
          subfamily is composed of the first SH3 domain (SH3A) of
          CD2AP, CIN85 (Cbl-interacting protein of 85 kDa), and
          similar domains. CD2AP and CIN85 are adaptor proteins
          that bind to protein partners and assemble complexes
          that have been implicated in T cell activation, kidney
          function, and apoptosis of neuronal cells. They also
          associate with endocytic proteins, actin cytoskeleton
          components, and other adaptor proteins involved in
          receptor tyrosine kinase (RTK) signaling. CD2AP and the
          main isoform of CIN85 contain three SH3 domains, a
          proline-rich region, and a C-terminal coiled-coil
          domain. All of these domains enable CD2AP and CIN85 to
          bind various protein partners and assemble complexes
          that have been implicated in many different functions.
          SH3A of both proteins bind to an atypical PXXXPR motif
          at the C-terminus of Cbl and the cytoplasmic domain of
          the cell adhesion protein CD2. CIN85 SH3A binds to
          internal proline-rich motifs within the proline-rich
          region; this intramolecular interaction serves as a
          regulatory mechanism to keep CIN85 in a closed
          conformation, preventing the recruitment of other
          proteins. CIN85 SH3A has also been shown to bind
          ubiquitin. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 53

 Score = 28.0 bits (63), Expect = 0.60
 Identities = 11/38 (28%), Positives = 16/38 (42%), Gaps = 5/38 (13%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQ 59
            FDYD  + D L         GDI+      ++ WW+
Sbjct: 4  VEFDYDAEEPDELT-----LKVGDIITNVKKMEEGWWE 36


>gnl|CDD|212851 cd11918, SH3_Vinexin_3, Third (or C-terminal) Src Homology 3
          domain of Vinexin, also called Sorbin and SH3 domain
          containing 3 (Sorbs3).  Vinexin is also called Sorbs3,
          SH3P3, and SH3-containing adapter molecule 1 (SCAM-1).
          It is an adaptor protein containing one sorbin homology
          (SoHo) and three SH3 domains. Vinexin was first
          identified as a vinculin binding protein; it is
          co-localized with vinculin at cell-ECM and cell-cell
          adhesion sites. There are several splice variants of
          vinexin: alpha, which contains the SoHo and three SH3
          domains and displays tissue-specific expression; and
          beta, which contains only the three SH3 domains and is
          widely expressed. Vinexin alpha stimulates the
          accumulation of F-actin at focal contact sites. Vinexin
          also promotes keratinocyte migration and wound healing.
          The SH3 domains of vinexin have been reported to bind a
          number of ligands including vinculin, WAVE2, DLG5, Abl,
          and Cbl. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 58

 Score = 28.0 bits (62), Expect = 0.70
 Identities = 11/38 (28%), Positives = 17/38 (44%), Gaps = 5/38 (13%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWW 58
          +A++ Y P  +D L         GD + V    DD W+
Sbjct: 5  KAVYQYRPQNEDELE-----LREGDRVDVMQQCDDGWF 37


>gnl|CDD|212941 cd12008, SH3_Src, Src homology 3 domain of Src Protein Tyrosine
          Kinase.  Src (or c-Src) is a cytoplasmic (or
          non-receptor) PTK and is the vertebrate homolog of the
          oncogenic protein (v-Src) from Rous sarcoma virus.
          Together with other Src subfamily proteins, it is
          involved in signaling pathways that regulate cytokine
          and growth factor responses, cytoskeleton dynamics,
          cell proliferation, survival, and differentiation. Src
          also play a role in regulating cell adhesion, invasion,
          and motility in cancer cells, and tumor vasculature,
          contributing to cancer progression and metastasis.
          Elevated levels of Src kinase activity have been
          reported in a variety of human cancers. Several
          inhibitors of Src have been developed as anti-cancer
          drugs. Src is also implicated in acute inflammatory
          responses and osteoclast function. Src kinases contain
          an N-terminal SH4 domain with a myristoylation site,
          followed by SH3 and SH2 domains, a tyr kinase domain,
          and a regulatory C-terminal region containing a
          conserved tyr. They are activated by
          autophosphorylation at the tyr kinase domain, but are
          negatively regulated by phosphorylation at the
          C-terminal tyr by Csk (C-terminal Src Kinase). The SH3
          domain of Src kinases contributes to substrate
          recruitment by binding adaptor proteins/substrates, and
          regulation of kinase activity through an intramolecular
          interaction. SH3 domains are protein interaction
          domains that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 56

 Score = 27.8 bits (61), Expect = 0.80
 Identities = 19/57 (33%), Positives = 29/57 (50%), Gaps = 11/57 (19%)

Query: 22 ALFDYDP-TKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          AL+DY+  T+ D      L F  G+ L + N ++ +WW A   L +G     G +PS
Sbjct: 4  ALYDYESRTETD------LSFKKGERLQIVNNTEGDWWLAHS-LTTGQT---GYIPS 50


>gnl|CDD|212993 cd12060, SH3_alphaPIX, Src Homology 3 domain of alpha-Pak
          Interactive eXchange factor.  Alpha-PIX, also called
          Rho guanine nucleotide exchange factor 6 (ARHGEF6) or
          Cool (Cloned out of Library)-2, activates small GTPases
          by exchanging bound GDP for free GTP. It acts as a GEF
          for both Cdc42 and Rac 1, and is localized in dendritic
          spines where it regulates spine morphogenesis. It
          controls dendritic length and spine density in the
          hippocampus. Mutations in the ARHGEF6 gene cause
          X-linked intellectual disability in humans. PIX
          proteins contain an N-terminal SH3 domain followed by
          RhoGEF (also called Dbl-homologous or DH) and
          Pleckstrin Homology (PH) domains, and a C-terminal
          leucine-zipper domain for dimerization. The SH3 domain
          of PIX binds to an atypical PxxxPR motif in
          p21-activated kinases (PAKs) with high affinity. The
          binding of PAKs to PIX facilitate the localization of
          PAKs to focal complexes and also localizes PAKs to PIX
          targets Cdc43 and Rac, leading to the activation of
          PAKs. SH3 domains are protein interaction domains that
          bind to proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 58

 Score = 27.7 bits (61), Expect = 0.87
 Identities = 12/40 (30%), Positives = 20/40 (50%), Gaps = 5/40 (12%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQA 60
          +A F++  T +D L         GDI++VT   +  WW+ 
Sbjct: 5  KARFNFKQTNEDELS-----VCKGDIIYVTRVEEGGWWEG 39


>gnl|CDD|212919 cd11986, SH3_Stac3_1, First C-terminal Src homology 3 domain of
          SH3 and cysteine-rich domain-containing protein 3
          (Stac3).  Stac proteins are putative adaptor proteins
          that contain a cysteine-rich C1 domain and one or two
          SH3 domains at the C-terminus. There are three
          mammalian members (Stac1, Stac2, and Stac3) of this
          family. Stac1 and Stac3 contain two SH3 domains while
          Stac2 contains a single SH3 domain at the C-terminus.
          Stac1 and Stac2 have been found to be expressed
          differently in mature dorsal root ganglia (DRG)
          neurons. Stac1 is mainly expressed in peptidergic
          neurons while Stac2 is found in a subset of
          nonpeptidergic and all trkB+ neurons. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 53

 Score = 27.6 bits (61), Expect = 1.00
 Identities = 12/32 (37%), Positives = 19/32 (59%), Gaps = 6/32 (18%)

Query: 30 KDDGLPSRGLPFHYGDILHVTNASDDEWWQAR 61
          KDD      L FH G+ + V + S++EWW+ +
Sbjct: 13 KDD------LDFHPGERITVIDDSNEEWWRGK 38


>gnl|CDD|178782 PLN03244, PLN03244, alpha-amylase; Provisional.
          Length = 872

 Score = 30.0 bits (67), Expect = 1.1
 Identities = 18/39 (46%), Positives = 26/39 (66%), Gaps = 6/39 (15%)

Query: 15  HLFSFSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNAS 53
           HLFSF + L D D  +++G+ SRGLP    +I HV +A+
Sbjct: 747 HLFSFDKDLMDLD--ENEGILSRGLP----NIHHVKDAA 779


>gnl|CDD|212945 cd12012, SH3_RIM-BP_2, Second Src homology 3 domain of
          Rab3-interacting molecules (RIMs) binding proteins.
          RIMs binding proteins (RBPs, RIM-BPs) associate with
          calcium channels present in photoreceptors, neurons,
          and hair cells; they interact simultaneously with
          specific calcium channel subunits, and active zone
          proteins, RIM1 and RIM2. RIMs are part of the matrix at
          the presynaptic active zone and are associated with
          synaptic vesicles through their interaction with the
          small GTPase Rab3. RIM-BPs play a role in regulating
          synaptic transmission by serving as adaptors and
          linking calcium channels with the synaptic vesicle
          release machinery. RIM-BPs contain three SH3 domains
          and two to three fibronectin III repeats. Invertebrates
          contain one, while vertebrates contain at least two
          RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called
          peripheral-type benzodiazapine receptor associated
          protein 1 (PRAX-1). Mammals contain a third protein,
          RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly
          expressed in the brain where they display overlapping
          but distinct expression patterns, while RIM-BP3 is
          almost exclusively expressed in the testis and is
          essential in spermiogenesis. The SH3 domains of RIM-BPs
          bind to the PxxP motifs of RIM1, RIM2, and L-type
          (alpha1D) and N-type (alpha1B) calcium channel
          subunits. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 62

 Score = 27.6 bits (62), Expect = 1.1
 Identities = 13/32 (40%), Positives = 15/32 (46%), Gaps = 5/32 (15%)

Query: 22 ALFDYDPT----KDDGLPSRGLPFHYGDILHV 49
          ALFDYDP       D      LPF  G ++ V
Sbjct: 4  ALFDYDPLTMSPNPDAA-EEELPFKEGQLIKV 34


>gnl|CDD|212888 cd11955, SH3_srGAP1-3, Src homology 3 domain of Slit-Robo GTPase
          Activating Proteins 1, 2, and 3.  srGAP1, also called
          Rho GTPase-Activating Protein 13 (ARHGAP13), is a
          Cdc42- and RhoA-specific GAP and is expressed later in
          the development of central nervous system tissues.
          srGAP2 is expressed in zones of neuronal
          differentiation. It plays a role in the regeneration of
          neurons and axons. srGAP3, also called MEGAP (MEntal
          disorder associated GTPase-Activating Protein), is a
          Rho GAP with activity towards Rac1 and Cdc42. It
          impacts cell migration by regulating actin and
          microtubule cytoskeletal dynamics. The association
          between srGAP3 haploinsufficiency and mental
          retardation is under debate. srGAPs are Rho GAPs that
          interact with Robo1, the transmembrane receptor of Slit
          proteins. Slit proteins are secreted proteins that
          control axon guidance and the migration of neurons and
          leukocytes. srGAPs contain an N-terminal F-BAR domain,
          a Rho GAP domain, and a C-terminal SH3 domain. SH3
          domains are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 53

 Score = 27.2 bits (60), Expect = 1.2
 Identities = 18/57 (31%), Positives = 28/57 (49%), Gaps = 11/57 (19%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPSK 78
          A FDY      G  +R L F  G  L + + + D+WW+ R    +G +   G+VP +
Sbjct: 4  AKFDYV-----GRSARELSFKKGASLLLYHRASDDWWEGRH---NGID---GLVPHQ 49


>gnl|CDD|212863 cd11930, SH3_SH3RF1_2, Second Src Homology 3 domain of SH3 domain
          containing ring finger protein 1, an E3
          ubiquitin-protein ligase.  SH3RF1 is also called POSH
          (Plenty of SH3s) or SH3MD2 (SH3 multiple domains
          protein 2). It is a scaffold protein that acts as an E3
          ubiquitin-protein ligase. It plays a role in calcium
          homeostasis through the control of the ubiquitin domain
          protein Herp. It may also have a role in regulating
          death receptor mediated and JNK mediated apoptosis.
          SH3RF1 also enhances the ubiquitination of ROMK1
          potassium channel resulting in its increased
          endocytosis. It contains an N-terminal RING finger
          domain and four SH3 domains. This model represents the
          second SH3 domain, located C-terminal of the first SH3
          domain at the N-terminal half, of SH3RF1. SH3 domains
          are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 55

 Score = 27.3 bits (60), Expect = 1.2
 Identities = 22/56 (39%), Positives = 29/56 (51%), Gaps = 7/56 (12%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVP 76
          +AL+D++  KD       LPF   DIL V    D+ W  A  +L  GD+  IGI P
Sbjct: 3  KALYDFE-VKDKEADKDCLPFAKDDILTVIRRVDENW--AEGML--GDK--IGIFP 51


>gnl|CDD|212777 cd11843, SH3_PACSIN, Src homology 3 domain of Protein kinase C
          and Casein kinase Substrate in Neurons (PACSIN)
          proteins.  PACSINs, also called Synaptic
          dynamin-associated proteins (Syndapins), act as
          regulators of cytoskeletal and membrane dynamics. They
          bind both dynamin and Wiskott-Aldrich syndrome protein
          (WASP), and may provide direct links between the actin
          cytoskeletal machinery through WASP and
          dynamin-dependent endocytosis. Vetebrates harbor three
          isoforms with distinct expression patterns and specific
          functions. PACSINs contain an N-terminal F-BAR domain
          and a C-terminal SH3 domain. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 53

 Score = 27.0 bits (60), Expect = 1.4
 Identities = 14/38 (36%), Positives = 19/38 (50%), Gaps = 5/38 (13%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWW 58
          RAL+DY+  + D      L F  GDIL      D++ W
Sbjct: 3  RALYDYEGQESD-----ELSFKAGDILTKLEEEDEQGW 35


>gnl|CDD|215519 PLN02960, PLN02960, alpha-amylase.
          Length = 897

 Score = 29.4 bits (66), Expect = 1.5
 Identities = 17/39 (43%), Positives = 21/39 (53%), Gaps = 6/39 (15%)

Query: 15  HLFSFSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNAS 53
           HLFSF +AL   D      + SRGLP    +I HV + S
Sbjct: 772 HLFSFDKALMALDEKY--LILSRGLP----NIHHVNDTS 804


>gnl|CDD|212918 cd11985, SH3_Stac2_C, C-terminal Src homology 3 domain of SH3 and
          cysteine-rich domain-containing protein 2 (Stac2).
          Stac proteins are putative adaptor proteins that
          contain a cysteine-rich C1 domain and one or two SH3
          domains at the C-terminus. There are three mammalian
          members (Stac1, Stac2, and Stac3) of this family. Stac2
          contains a single SH3 domain at the C-terminus unlike
          Stac1 and Stac3, which contain two C-terminal SH3
          domains. Stac1 and Stac2 have been found to be
          expressed differently in mature dorsal root ganglia
          (DRG) neurons. Stac1 is mainly expressed in peptidergic
          neurons while Stac2 is found in a subset of
          nonpeptidergic and all trkB+ neurons. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 53

 Score = 26.8 bits (59), Expect = 1.7
 Identities = 16/56 (28%), Positives = 30/56 (53%), Gaps = 11/56 (19%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQGIGIVPS 77
          AL+ + P +++ LP        GD + V + S+++WW+ +    SGD   +G  P+
Sbjct: 4  ALYKFLPQENNDLP-----LQPGDRVMVVDDSNEDWWKGK----SGDR--VGFFPA 48


>gnl|CDD|212987 cd12054, SH3_CD2AP_2, Second Src Homology 3 domain (SH3B) of
          CD2-associated protein.  CD2AP, also called CMS (Cas
          ligand with Multiple SH3 domains) or METS1
          (Mesenchyme-to-Epithelium Transition protein with SH3
          domains), is a cytosolic adaptor protein that plays a
          role in regulating the cytoskeleton. It is critical in
          cell-to-cell union necessary for kidney function. It
          also stabilizes the contact between a T cell and
          antigen-presenting cells. It is primarily expressed in
          podocytes at the cytoplasmic face of the slit diaphragm
          and serves as a linker anchoring podocin and nephrin to
          the actin cytoskeleton. CD2AP contains three SH3
          domains, a proline-rich region, and a C-terminal
          coiled-coil domain. All of these domains enable CD2AP
          to bind various protein partners and assemble complexes
          that have been implicated in many different functions.
          This alignment model represents the second SH3 domain
          (SH3B) of CD2AP. SH3B binds to c-Cbl in a site
          (TPSSRPLR is the core binding motif) distinct from the
          c-Cbl/SH3A binding site. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 55

 Score = 26.5 bits (58), Expect = 2.0
 Identities = 17/58 (29%), Positives = 25/58 (43%), Gaps = 13/58 (22%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQG-IGIVPS 77
          + LF+Y P  +D L         GDI+ +    ++ WW       SG   G  G+ PS
Sbjct: 4  KVLFEYVPQNEDELE-----LKVGDIIDINEEVEEGWW-------SGTLNGKSGLFPS 49


>gnl|CDD|212717 cd11783, SH3_SH3RF_3, Third Src Homology 3 domain of SH3 domain
          containing ring finger 1 (SH3RF1), SH3RF3, and similar
          domains.  SH3RF1 (or POSH) and SH3RF3 (or POSH2) are
          scaffold proteins that function as E3 ubiquitin-protein
          ligases. They contain an N-terminal RING finger domain
          and four SH3 domains. This model represents the third
          SH3 domain, located in the middle of SH3RF1 and SH3RF3,
          and similar domains. SH3RF1 plays a role in calcium
          homeostasis through the control of the ubiquitin domain
          protein Herp. It may also have a role in regulating
          death receptor mediated and JNK mediated apoptosis.
          SH3RF3 interacts with p21-activated kinase 2 (PAK2) and
          GTP-loaded Rac1. It may play a role in regulating JNK
          mediated apoptosis in certain conditions. SH3 domains
          are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 55

 Score = 26.6 bits (59), Expect = 2.2
 Identities = 12/36 (33%), Positives = 15/36 (41%), Gaps = 5/36 (13%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEW 57
          AL+ Y P K D      L    G++  VT    D W
Sbjct: 4  ALYPYKPQKPD-----ELELRKGEMYTVTEKCQDGW 34


>gnl|CDD|212747 cd11813, SH3_SGSM3, Src Homology 3 domain of Small G protein
          Signaling Modulator 3.  SGSM3 is also called
          Merlin-associated protein (MAP), RUN and SH3
          domain-containing protein (RUSC3), RUN and TBC1
          domain-containing protein 3 (RUTBC3), Rab
          GTPase-activating protein 5 (RabGAP5), or Rab GAP-like
          protein (RabGAPLP). It is expressed ubiquitously and
          functions as a regulator of small G protein RAP- and
          RAB-mediated neuronal signaling. It is involved in
          modulating NGF-mediated neurite outgrowth and
          differentiation. It also interacts with the tumor
          suppressor merlin and may play a role in the
          merlin-associated suppression of cell growth. SGSM3
          contains TBC, SH3, and RUN domains. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 53

 Score = 26.3 bits (58), Expect = 2.3
 Identities = 11/39 (28%), Positives = 19/39 (48%), Gaps = 5/39 (12%)

Query: 20 SRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWW 58
          ++AL D++   DD L      F   DI+ + +  D+  W
Sbjct: 2  AKALLDFERHDDDELG-----FRKNDIITIISQKDEHCW 35


>gnl|CDD|212879 cd11946, SH3_GRB2_N, N-terminal Src homology 3 domain of Growth
          factor receptor-bound protein 2.  GRB2 is a critical
          signaling molecule that regulates the Ras pathway by
          linking tyrosine kinases to the Ras guanine nucleotide
          releasing protein Sos (son of sevenless), which
          converts Ras to the active GTP-bound state. It is
          ubiquitously expressed in all tissues throughout
          development and is important in cell cycle progression,
          motility, morphogenesis, and angiogenesis. In
          lymphocytes, GRB2 is associated with antigen receptor
          signaling components. GRB2 contains an N-terminal SH3
          domain, a central SH2 domain, and a C-terminal SH3
          domain. Its N-terminal SH3 domain binds to Sos and
          Sos-derived proline-rich peptides. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 56

 Score = 26.1 bits (57), Expect = 2.8
 Identities = 16/40 (40%), Positives = 20/40 (50%), Gaps = 6/40 (15%)

Query: 22 ALFDYDPTKDDGLPSRGLPFHYGDILHVTN-ASDDEWWQA 60
          A +D+  T DD L      F  GDIL V N   D  W++A
Sbjct: 5  AKYDFKATADDELS-----FKRGDILKVLNEECDQNWYKA 39


>gnl|CDD|212794 cd11860, SH3_DLG5, Src homology 3 domain of Disks Large homolog
          5.  DLG5 is a multifunctional scaffold protein that is
          located at sites of cell-cell contact and is involved
          in the maintenance of cell shape and polarity.
          Mutations in the DLG5 gene are associated with Crohn's
          disease (CD) and inflammatory bowel disease (IBD). DLG5
          is a member of the MAGUK (membrane-associated guanylate
          kinase) protein family, which is characterized by the
          presence of a core of three domains: PDZ, SH3, and
          guanylate kinase (GuK). The GuK domain in MAGUK
          proteins is enzymatically inactive; instead, the domain
          mediates protein-protein interactions and associates
          intramolecularly with the SH3 domain. DLG5 contains 4
          PDZ domains as well as an N-terminal domain of unknown
          function. SH3 domains are protein interaction domains
          that bind to proline-rich ligands with moderate
          affinity and selectivity, preferentially to PxxP
          motifs. They play versatile and diverse roles in the
          cell including the regulation of enzymes, changing the
          subcellular localization of signaling pathway
          components, and mediating the formation of multiprotein
          complex assemblies.
          Length = 63

 Score = 26.1 bits (58), Expect = 3.2
 Identities = 23/67 (34%), Positives = 32/67 (47%), Gaps = 8/67 (11%)

Query: 19 FSRALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDE---WWQARRVLPSGDEQGIGIV 75
          + RALFD     +D L      F   DIL+V N   +     W+A  V   G ++  GI+
Sbjct: 1  YVRALFDRSAENEDELS-----FKKDDILYVDNTMFNGVFGQWRAWLVDEEGRKRKCGII 55

Query: 76 PSKKRWE 82
          PSK + E
Sbjct: 56 PSKYKVE 62


>gnl|CDD|212728 cd11794, SH3_DNMBP_N1, First N-terminal Src homology 3 domain of
          Dynamin Binding Protein, also called Tuba.  DNMBP or
          Tuba is a cdc42-specific guanine nucleotide exchange
          factor (GEF) that contains four N-terminal SH3 domains,
          a central RhoGEF [or Dbl homology (DH)] domain followed
          by a Bin/Amphiphysin/Rvs (BAR) domain, and two
          C-terminal SH3 domains. It provides a functional link
          between dynamin and key regulatory proteins of the
          actin cytoskeleton. It plays an important role in
          regulating cell junction configuration. The four
          N-terminal SH3 domains of DNMBP binds the GTPase
          dynamin, which plays an important role in the fission
          of endocytic vesicles. SH3 domains are protein
          interaction domains that bind to proline-rich ligands
          with moderate affinity and selectivity, preferentially
          to PxxP motifs. They play versatile and diverse roles
          in the cell including the regulation of enzymes,
          changing the subcellular localization of signaling
          pathway components, and mediating the formation of
          multiprotein complex assemblies.
          Length = 51

 Score = 25.9 bits (57), Expect = 3.5
 Identities = 13/37 (35%), Positives = 19/37 (51%), Gaps = 5/37 (13%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEW 57
          RA+FD+ P+      S  LP   GD++ V    D+ W
Sbjct: 3  RAIFDFCPSV-----SEELPLFAGDVIEVLKVVDEFW 34


>gnl|CDD|212898 cd11965, SH3_ASAP1, Src homology 3 domain of ArfGAP with SH3
          domain, ankyrin repeat and PH domain containing protein
          1.  ASAP1 is also called DDEF1 (Development and
          Differentiation Enhancing Factor 1), AMAP1, centaurin
          beta-4, or PAG2. an Arf GTPase activating protein (GAP)
          with activity towards Arf1 and Arf5 but not Arf6.
          However, it has been shown to bind GTP-Arf6 stably
          without GAP activity. It has been implicated in cell
          growth, migration, and survival, as well as in tumor
          invasion and malignancy. It binds paxillin and
          cortactin, two components of invadopodia which are
          essential for tumor invasiveness. It also binds focal
          adhesion kinase (FAK) and the SH2/SH3 adaptor CrkL.
          ASAP1 contains an N-terminal BAR domain, followed by a
          Pleckstrin homology (PH) domain, an Arf GAP domain,
          ankyrin (ANK) repeats, and a C-terminal SH3 domain. SH3
          domains are protein interaction domains that bind to
          proline-rich ligands with moderate affinity and
          selectivity, preferentially to PxxP motifs. They play
          versatile and diverse roles in the cell including the
          regulation of enzymes, changing the subcellular
          localization of signaling pathway components, and
          mediating the formation of multiprotein complex
          assemblies.
          Length = 57

 Score = 26.1 bits (57), Expect = 3.6
 Identities = 12/38 (31%), Positives = 18/38 (47%), Gaps = 5/38 (13%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWW 58
          + ++D     DD L      F  G+++ VT   D EWW
Sbjct: 3  KTIYDCQADNDDELT-----FVEGEVIIVTGEEDQEWW 35


>gnl|CDD|212715 cd11781, SH3_Sorbs_1, First Src Homology 3 domain of Sorbin and
          SH3 domain containing (Sorbs) proteins and similar
          domains.  This family, also called the vinexin family,
          is composed predominantly of adaptor proteins
          containing one sorbin homology (SoHo) and three SH3
          domains. Members include the first SH3 domains of
          Sorbs1 (or ponsin), Sorbs2 (or ArgBP2), Vinexin (or
          Sorbs3), and similar domains. They are involved in the
          regulation of cytoskeletal organization, cell adhesion,
          and growth factor signaling. Members of this family
          bind multiple partners including signaling molecules
          like c-Abl, c-Arg, Sos, and c-Cbl, as well as
          cytoskeletal molecules such as vinculin and afadin.
          They may have overlapping functions. SH3 domains are
          protein interaction domains that bind to proline-rich
          ligands with moderate affinity and selectivity,
          preferentially to PxxP motifs. They play versatile and
          diverse roles in the cell including the regulation of
          enzymes, changing the subcellular localization of
          signaling pathway components, and mediating the
          formation of multiprotein complex assemblies.
          Length = 53

 Score = 25.0 bits (55), Expect = 6.2
 Identities = 14/58 (24%), Positives = 26/58 (44%), Gaps = 13/58 (22%)

Query: 21 RALFDYDPTKDDGLPSRGLPFHYGDILHVTNASDDEWWQARRVLPSGDEQG-IGIVPS 77
          RAL+ +         ++ L    GDI+++    D  W++       G+  G +GI P+
Sbjct: 3  RALYPFKAQS-----AKELSLKKGDIIYIRRQIDKNWYE-------GEHNGRVGIFPA 48


>gnl|CDD|237131 PRK12536, PRK12536, RNA polymerase sigma factor; Provisional.
          Length = 181

 Score = 26.6 bits (59), Expect = 8.4
 Identities = 27/85 (31%), Positives = 36/85 (42%), Gaps = 23/85 (27%)

Query: 52  ASDDEWWQARRVLPSGDEQGIGIVPSKKRWERKQRARDRTVKFQGHVPVLLEKVSITQFS 111
            SDDE  +ARR L    EQ    +P +      QR     VK +G              S
Sbjct: 111 TSDDEAAEARRDLGKLLEQ----LPDR------QRLPIVHVKLEG-------------LS 147

Query: 112 MIELNTIFKLIEKSVALGLTRGLKA 136
           + E   +  L E +V +G+ RGLKA
Sbjct: 148 VAETAQLTGLSESAVKVGIHRGLKA 172


  Database: CDD.v3.10
    Posted date:  Mar 20, 2013  7:55 AM
  Number of letters in database: 10,937,602
  Number of sequences in database:  44,354
  
Lambda     K      H
   0.323    0.139    0.412 

Gapped
Lambda     K      H
   0.267   0.0813    0.140 


Matrix: BLOSUM62
Gap Penalties: Existence: 11, Extension: 1
Number of Sequences: 44354
Number of Hits to DB: 10,779,070
Number of extensions: 1018020
Number of successful extensions: 977
Number of sequences better than 10.0: 1
Number of HSP's gapped: 941
Number of HSP's successfully gapped: 135
Length of query: 207
Length of database: 10,937,602
Length adjustment: 92
Effective length of query: 115
Effective length of database: 6,857,034
Effective search space: 788558910
Effective search space used: 788558910
Neighboring words threshold: 11
Window for multiple hits: 40
X1: 16 ( 7.5 bits)
X2: 38 (14.6 bits)
X3: 64 (24.7 bits)
S1: 41 (22.0 bits)
S2: 57 (25.6 bits)