Acts as chemorepulsive guidance molecule critical for axon fasciculation and for determining both the initial direction and subsequent pathfinding events of the Ti axon projection.
Plays a role in growth cones guidance. Required for both proper adult behavior and survival. Can function in vivo as a selective target-derived signal that inhibits the formation of specific synaptic terminal arbors.
Bifunctional axonal guidance cue regulated by sulfated proteoglycans; attractive effects result from interactions with heparan sulfate proteoglycans (HSPGs), while the inhibitory effects depend on interactions with chondroitin sulfate proteoglycans (CSPGs). Ligand for receptor PLXNB3. In glioma cells, SEMA5A stimulation of PLXNB3 results in the disassembly of F-actin stress fibers, disruption of focal adhesions and cellular collapse as well as inhibition of cell migration and invasion through ARHGDIA-mediated inactivation of RAC1. May promote angiogenesis by increasing endothelial cell proliferation and migration and inhibiting apoptosis.
Sema1A is a transmembrane protein. It has been shown to mediate the defasciculation of motor axon bundles at specific choice points. Sema1A binds to its receptor plexin A (PlexA), which in turn triggers downstream signaling events involving the receptor tyrosine kinase Otk, the evolutionarily conserved flavoprotein monooxygenase molecule interacting with CasL (MICAL), and the A kinase anchoring protein Nervy, leading to repulsive growth-cone response. Sema1A has also been shown to be involved in synaptic formation. It is a member of the semaphorin family of proteins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 446
>gnl|CDD|200496 cd11235, Sema_semaphorin, The Sema domain, a protein interacting module, of semaphorins
Semaphorins are regulator molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. They can be divided into 7 classes. Vertebrates have members in classes 3-7, whereas classes 1 and 2 are known only in invertebrates. Class 2 and 3 semaphorins are secreted proteins; classes 1 and 4 through 6 are transmembrane proteins; and class 7 is membrane associated via glycosylphosphatidylinositol (GPI) linkage. The semaphorins exert their function through their receptors, the neuropilin and plexin families. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 437
>gnl|CDD|200526 cd11265, Sema_5C, The Sema domain, a protein interacting module, of semaphorin 5C (sema5C)
In Drosophila, Sema5C was identified as an early development gene, which is expressed in stage 2 embryos with a striped pattern emerging at later stages. Sema5c may play a role in odor-guided behavior and in tumorigenesis. Sema5C belongs to class 5 semaphorin family of proteins, which are transmembrane glycoproteins characterized by unique thrombospondin specific repeats in the extracellular region of the protein. Semaphorins are regulatory molecules involved in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 433
>gnl|CDD|200499 cd11238, Sema_2A, The Sema domain, a protein interacting module, of semaphorin 2A (Sema2A)
Sema2A, a secreted semaphorin, signals through its receptor plexin B (PlexB) to regulate central and peripheral axon pathfinding. In the Drosophila embryo, Sema2A secreted by oenocytes interacts with PlexB to guide sensory axons. Sema2A is a member of the semaphorin family of proteins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 452
>gnl|CDD|200502 cd11241, Sema_5, The Sema domain, a protein interacting module, of semaphorin 5 (Sema5)
Class 5 semaphorins are transmembrane glycoproteins characterized by unique thrombospondin specific repeats in the extracellular region of the protein. There are three subfamilies in class 5 semaphorins, namely 5A, 5B and 5C. Sema5A and Sema5B function as guidance cues for optic and corticofugal nerve development, respectively. Sema5A-induced cell migration requires Met signaling. Sema5C is an early development gene and may play a role in odor-guided behavior. Sema5A is also implicated in cancer. In a screening model for metastasis, the Drosophila Sema5A ortholog, Dsema-5C, has been found to be required in tumorigenicity and metastasis. Sema5A is highly expressed in human pancreatic cancer cells and is associated with tumor growth, invasion and metastasis. Semaphorins are regulatory molecules involved in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 438
The Sema domain occurs in semaphorins, which are a large family of secreted and transmembrane proteins, some of which function as repellent signals during axon guidance. Sema domains also occur in the hepatocyte growth factor receptor and human plexin A-3. Length = 435
>gnl|CDD|200503 cd11242, Sema_6, The Sema domain, a protein interacting module, of class 6 semaphorins (Sema6)
Class 6 semaphorins (Sema6s) are membrane associated semaphorins. There are 6 subfamilies named 6A to 6D. Sema6s bind to plexin As in a neuropilin independent fashion. Sema6-plexin A signaling plays important roles in lamina-specific axon projections. Interactions between plexin A2, plexin A4, and Sema6A control lamina-restricted projection of hippocampal mossy fibers. Interactions between Sema6C, Sema6D and plexin A1 shape the stereotypic trajectories of sensory axons in the spinal cord. In addition to axon targeting, Sema6D-plexin A1 interactions influence a wide range of other biological processes. During cardiac development, Sema6D attracts or repels endothelial cells in the cardiac tube depending on the expression patterns of specific coreceptors in addition to plexin A1. Furthermore, Sema6D binds a receptor complex comprising of plexin A1, Trem2 (triggering receptor expressed on myeloid cells 2), and DAP12 on dendritic cells and osteoclasts to mediate T-cell-DC interactions and to control bone development, respectively. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 465
>gnl|CDD|200524 cd11263, Sema_5A, The Sema domain, a protein interacting module, of semaphorin 5A (Sema5A)
Originally, mouse Sema5A was identified as a protein that induces inhibitory responses during optic nerve development. Recent studies show that Sema5A controls innate immunity in mice. It also has been identified as a candidate gene for causing idiopathic autism in humans. Plexin B3 functions as a binding partner and receptor for Sema5A. Furthermore, Sema5A is also implicated in cancer. The role of the Drosophila Sema5A ortholog, Dsema-5C, in tumorigenicity and metastasis has been reported. Sema5A is highly expressed in human pancreatic cancer cells and is associated with tumor growth, invasion and metastasis. Sema5A belongs to class 5 semaphorin family of proteins, which are transmembrane glycoproteins characterized by unique thrombospondin specific repeats in the extracellular region of the protein. Semaphorins are regulatory molecules involved in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 436
>gnl|CDD|200525 cd11264, Sema_5B, The Sema domain, a protein interacting module, of semaphorin 5B (Sema5B)
Sema5B is expressed in regions of the basal telencephalon in rat. Sema5B is an inhibitory cue for corticofugal axons and acts as a source of repulsion for the appropriate guidance of cortical axons away from structures such as the ventricular zone as they navigate toward and within subcortical regions. In addition to its role as a guidance cue, Sema5B regulates the development and maintenance of synapse size and number in hippocampal neurons. In addition, the sema domain of Sema5B can be cleaved of the whole protein and exerts its function in regulation of synapse morphology. Sema5B belongs to the class 5 semaphorin family of proteins, which are transmembrane glycoproteins characterized by unique thrombospondin specific repeats in the extracellular region of the protein. Semaphorins are regulatory molecules involved in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 437
>gnl|CDD|200530 cd11269, Sema_6D, The Sema domain, a protein interacting module, of semaphorin 6D (Sema6D)
Sema6D is expressed predominantly in the nervous system during embryogenesis and it uses Plexin-A1 as a receptor. It displays repellent activity for dorsal root ganglion axons. Sema6D also acts as a regulator of late phase primary immune responses. In addition, Sema6D is overexpressed in gastric carcinoma, indicating that it may have an important role in the occurrence and development of the cancer. Sema6D is a member of the class 6 semaphorin family of proteins, which are membrane associated semaphorins. Semaphorins are regulatory molecules involved in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 465
>gnl|CDD|200529 cd11268, Sema_6C, The Sema domain, a protein interacting module, of semaphorin 6C (Sema6C, also called semaphorin Y)
Sema6C is highly expressed in adult brain and skeletal muscle and it shows growth cone collapsing activity. It may play a role in the maintenance and remodelling of neuronal connections. In adult skeletal muscle, this role includes prevention of motor neuron sprouting and uncontrolled motor neuron growth. The expression of Sema6C in adult skeletal muscle is down-regulated following denervation. Sema6C is a member of the class 6 semaphorin family of proteins, which are membrane associated semaphorins. Semaphorins are regulatory molecules involved in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 465
>gnl|CDD|200527 cd11266, Sema_6A, The Sema domain, a protein interacting module, of semaphorins 6A (Sema6A)
In the cerebellum, Sema6A-plexin A2 signaling modulates granule cell migration by controlling centrosome positioning. Besides plexin A2, plexin A4 is also found to be a receptor of Sema6A. Interactions between plexin A2, plexin A4, and Sema6A control lamina-restricted projection of hippocampal mossy fibers. It is required for the clustering of boundary cap cells at the PNS/CNS interface and thus, prevents motoneurons from streaming out of the ventral spinal cord. At the dorsal root entry site, it organizes the segregation of dorsal roots. Sema6A may also be involved in axonal pathfinding processes in the periinfarct and homotopic contralateral cortex. Sema6A is a member of the class 6 semaphorin family of proteins, which are membrane associated semaphorins. Semaphorins are regulatory molecules involved in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 466
>gnl|CDD|200528 cd11267, Sema_6B, The Sema domain, a protein interacting module, of semaphorin 6B (Sema6B)
Score = 112 bits (281), Expect = 1e-30
Identities = 55/105 (52%), Positives = 67/105 (63%), Gaps = 6/105 (5%)
Query: 1 MDPIIYRE-----PLQTEQYDSMSLNAPNFVSSLTQGDFVYFFFRETAVEFINCGKAVYS 55
+D +IYR L+T ++DS P FV ++ G VYFFFRE A+EF K V S
Sbjct: 146 IDAVIYRSLGDSPALRTVKHDSKWFKEPYFVHAVEWGSHVYFFFREIAMEFNYLEKVVVS 205
Query: 56 RVARVCKYDRGGPHR-FRNRWTSFLKSRLNCSVPGDFPFYFDEIQ 99
RVARVCK D GG R +WTSFLK+RLNCSVPGD FYF+ +Q
Sbjct: 206 RVARVCKNDMGGSQRVLEKQWTSFLKARLNCSVPGDSHFYFNVLQ 250
Sema6B functions as repellents for axon growth; this repulsive activity is mediated by its receptor Plexin A4. Sema6B is expressed in CA3, and repels mossy fibers in a Plexin A4 dependent manner. In human, it was shown that peroxisome proliferator-activated receptors (PPARs) and 9-cis-retinoic acid receptor (RXR) regulate human semaphorin 6B (Sema6B) gene expression. Sema6B is a member of the class 6 semaphorin family of proteins, which are membrane associated semaphorins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 466
>gnl|CDD|200531 cd11270, Sema_6E, The Sema domain, a protein interacting module, semaphorin 6E (sema6E)
Sema6E is expressed predominantly in the nervous system during embryogenesis. It binds Plexin A1 and might utilize it as a receptor to repel axons of specific types during development. Sema6E acts as a repellent to dorsal root ganglion axons as well as sympathetic axons. Sema6E is a member of the class 6 semaphorin family of proteins, which are membrane associated semaphorins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 462
>gnl|CDD|200500 cd11239, Sema_3, The Sema domain, a protein interacting module, of class 3 semaphorins
Class 3 semaphorins (Sema3s) are secreted regulator molecules involved in the development of the nervous system, vasculogenesis, angiogenesis,and tumorigenesis. There are 7 distinct subfamilies named Sema3A to 3G. Sema3s function as repellent signals during axon guidance by repelling neurons away from the source of Sema3s. However, Sema3s that are secreted by tumor cells play an inhibitory role in tumor growth and angiogenesis (specifically Sema3B and Sema3F). Sema3s functions by forming complexes with neuropilins and A-type plexins, where neuropilins serve as the ligand binding moiety and the plexins function as signal transduction component. Sema3s primarily inhibit the cell motility and migration of tumor and endothelial cells by inducing collapse of the actin cytoskeleton via neuropilins and plexins. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 471
>gnl|CDD|200511 cd11250, Sema_3B, The Sema domain, a protein interacting module, of semaphorin 3B (Sema3B)
Sema3B is coexpressed with semaphorin 3F and both proteins are candidate tumor suppressors. Both Sema3B and Sema3F show high levels of expression in normal tissues and low-grade tumors but are down-regulated in highly metastatic tumors in the lung, melanoma cells, bladder carcinoma cells and prostate carcinoma. They are upregulated by estrogen and inhibit cell motility and invasiveness through decreased FAK phosphorylation and inhibition of MMP-2 and MMP-9 expression. Two receptor families, the neuropilins (NP) and plexins, have been implicated in mediating the actions of semaphorins 3B and 3F. Sema3B is a member of the class 3 semaphorin family of proteins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 471
>gnl|CDD|200515 cd11254, Sema_3F, The Sema domain, a protein interacting module, of semaphorin 3F (Sema3F)
Score = 91.4 bits (227), Expect = 3e-23
Identities = 47/112 (41%), Positives = 63/112 (56%), Gaps = 15/112 (13%)
Query: 2 DPIIYRE-----PLQTEQYDSMSLNAPNFV-------SSLTQGDFVYFFFRETAVEFINC 49
D I+R ++T+QY+S LN P FV SS D +YFFFRE ++E
Sbjct: 152 DAAIFRTMGKQPAMRTDQYNSRWLNDPAFVHAHLIPDSSEKNDDKLYFFFREKSLEAPQ- 210
Query: 50 GKAVYSRVARVCKYDRGGPHRFRNRWTSFLKSRLNCSVPGD--FPFYFDEIQ 99
AV SR+ RVC D GG N+W++FLK+RL CSVPG +FDE++
Sbjct: 211 SPAVLSRIGRVCLNDDGGHCCLVNKWSTFLKARLVCSVPGADGIETHFDELR 262
Sema3F is coexpressed with semaphorin3B. Both Sema3B and Sema3F proteins are candidate tumor suppressors that are down-regulated in highly metastatic tumors. Two receptor families, the neuropilins and plexins, have been implicated in mediating the actions of semaphorins 3B and 3F. Sema3F is a member of the class 3 semaphorin family of proteins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 470
>gnl|CDD|200510 cd11249, Sema_3A, The Sema domain, a protein interacting module, of semaphorin 3A (Sema3A)
Sema3A has been reported to inhibit the growth of certain experimental tumors and to regulate endothelial cell migration and apoptosis in vitro, as well as arteriogenesis in the muscle, skin vessel permeability, and tumor angiogenesis in vivo. The function of Sema3A is mediated through receptors neuropilin-1 (NP1) and plexins, although little is known about the requirement of specific plexins in its receptor complex. It is known however that Plexin-A4 is the receptor for Sema3A in the Toll-like receptor- and sepsis-induced cytokine storm during immune response. Sema3A is a member of the Class 3 semaphorin family of secreted proteins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 493
>gnl|CDD|200514 cd11253, Sema_3E, The Sema domain, a protein interacting module, of semaphorin 3E (Sema3E)
Score = 86.8 bits (215), Expect = 2e-21
Identities = 44/112 (39%), Positives = 59/112 (52%), Gaps = 14/112 (12%)
Query: 2 DPIIYR-----EPLQTEQYDSMSLNAPNFVSSLT-------QGDFVYFFFRETAVEFINC 49
D I+R ++TE D L P FV S + VYFFF E A+E
Sbjct: 151 DAAIFRTMNHLAHIRTEHDDERLLKEPKFVGSYMIPDNEDPDDNKVYFFFTEKALEAEGG 210
Query: 50 GKAVYSRVARVCKYDRGGPHRFRNRWTSFLKSRLNCSVPG--DFPFYFDEIQ 99
A+Y+RV RVC D+GG N+W++FLK+RL CSVPG +FDE++
Sbjct: 211 NHAIYTRVGRVCANDQGGQRMLVNKWSTFLKTRLICSVPGPNGIDTHFDELE 262
Sema3E is a secreted molecule implicated in axonal path finding and inhibition of developmental and postischemic angiogenesis. It is also highly expressed in metastatic cancer cells. Sema3E signaling, through its high affinity functional receptor Plexin D1, drives cancer cell invasiveness and metastatic spreading. Sema3E is a member of the class 3 semaphorin family of proteins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 471
>gnl|CDD|200501 cd11240, Sema_4, The Sema domain, a protein interacting module, of class 4 semaphorins (Sema4)
Score = 85.9 bits (213), Expect = 3e-21
Identities = 45/107 (42%), Positives = 54/107 (50%), Gaps = 17/107 (15%)
Query: 3 PIIYR-----EPLQTEQYDSMSLNAPNFVSS----------LTQGDFVYFFFRETAVEFI 47
P+I R L+TE LN P FV S D +YFFF ETAVE+
Sbjct: 147 PVISRNHSEGNVLKTE-NTLRWLNEPAFVGSAHIRESIDSPDGDDDKIYFFFTETAVEYD 205
Query: 48 NCGKAVYSRVARVCKYDRGGPHRFRNRWTSFLKSRLNCSVPG-DFPF 93
K SRVARVCK D GG + +WT+FLK++L CS P PF
Sbjct: 206 FYEKVTVSRVARVCKGDLGGQRTLQKKWTTFLKAQLVCSQPDSGLPF 252
Class 4 semaphorins (Sema4s) are transmembrane regulator molecules involved in the development of the nervous system, immune response, cytoskeletal organization, angiogenesis, and cell-cell interactions. There are 7 distinct subfamilies in class 4 semaphorins, named 4A to 4G. Several class 4 subfamilies play important roles in the immune system and are called "immune semaphorins". Sema4A plays critical roles in T cell-DC interactions in the immune response. Sema4D/CD100, expressed by lymphocytes, promotes the aggregation and survival of B lymphocytes and inhibits cytokine-induced migration of immune cells in vitro. It is required for normal activation of B and T lymphocytes. Sema4B negatively regulates basophil functions through T cell-basophil contacts and significantly inhibits IL-4 and IL-6 production from basophils in response to various stimuli, including IL-3 and papain. Sema4s not only influence the activation state of cells but also modulate their migration and survival. The effects of Sema4s on nonlymphoid cells are mediated by plexin D1 and plexin Bs. The Sema4G and Sema4C genes are expressed in the developing cerebellar cortex and are involved in neural tube closure and development of cerebellar granules cells through receptor plexin B2. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 456
>gnl|CDD|200519 cd11258, Sema_4C, The Sema domain, a protein interacting module, of semaphorin 4C (Sema4C)
Score = 84.5 bits (209), Expect = 1e-20
Identities = 44/113 (38%), Positives = 65/113 (57%), Gaps = 17/113 (15%)
Query: 2 DPIIYR-----EPLQTEQYDSMSLNAPNFVSS----------LTQGDFVYFFFRETAVEF 46
+P+I R ++TE Y + LN P+FV S D +YFFF E AVE+
Sbjct: 147 EPVILRNLGQHYSMKTE-YLAFWLNEPHFVGSAFVPESVGSFTGDDDKIYFFFSERAVEY 205
Query: 47 INCGKAVYSRVARVCKYDRGGPHRFRNRWTSFLKSRLNCSVPGDFPFYFDEIQ 99
+ V +RVARVCK D GG + +WT+FLK+RL CS+P ++ YF++++
Sbjct: 206 DCDSEQVVARVARVCKGDLGGARTLQKKWTTFLKARLLCSIP-EWQLYFNQLK 257
Sema4C acts as a Plexin B2 ligand to regulate the development of cerebellar granule cells and to modulate ureteric branching in the developing kidney. The binding of Sema4C to Plexin B2 results the phosphorylation of downstream regulator ErbB-2 and the plexin protein itself. The cytoplasmic region of Sema4C binds a neurite-outgrowth-related protein SFAP75, suggesting that Sema4C may also play a role in neural function. Sema4C belongs to the class 4 transmembrane semaphorin family of proteins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 458
>gnl|CDD|200521 cd11260, Sema_4E, The Sema domain, a protein interacting module, of semaphorin 4E (Sema4E)
Score = 81.5 bits (201), Expect = 1e-19
Identities = 45/100 (45%), Positives = 60/100 (60%), Gaps = 14/100 (14%)
Query: 2 DPIIYR---EPLQTEQYDSMSLNAPNFVS--SLTQG--------DFVYFFFRETAVEFIN 48
+P+I R ++TE + S LN PNF+ ++ + D +Y FF ETAVE+
Sbjct: 146 EPVIMRSSPITIRTE-FKSSWLNEPNFIYMAAVPESEDSPEGDDDKIYLFFSETAVEYDF 204
Query: 49 CGKAVYSRVARVCKYDRGGPHRFRNRWTSFLKSRLNCSVP 88
K V SRVARVCK D GG + +WTSFLK+RL+CSVP
Sbjct: 205 YNKLVVSRVARVCKGDLGGQRTLQKKWTSFLKARLDCSVP 244
Sema4E is expressed in the epithelial cells that line the pharyngeal arches in zebrafish. It may act as a guidance molecule to restrict the branchiomotor axons to the mesenchymal cells. Gain-of-function and loss-of-function studies demonstrate that Sema4E is essential for the guidance of facial axons from the hindbrain into their pharyngeal arch targets and is sufficient for guidance of gill motor axons. Sema4E guides facial motor axons by a repulsive action. Sema4E belongs to the class 4 transmembrane semaphorin family of proteins. Semaphorins are regulatory molecules involved in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 456
>gnl|CDD|200518 cd11257, Sema_4B, The Sema domain, a protein interacting module, of semaphorin 4B (Sema4B)
Score = 81.4 bits (201), Expect = 1e-19
Identities = 51/111 (45%), Positives = 60/111 (54%), Gaps = 23/111 (20%)
Query: 2 DPIIYRE-----PLQTEQYDSMSLN---APNFVSSL--------TQG--DFVYFFFRETA 43
DPIIYR PL+TE SLN P FV S G D +YFFF ET
Sbjct: 153 DPIIYRSLGSGTPLKTEN----SLNWLQDPAFVGSAYIQESLPKLVGDDDKIYFFFSETG 208
Query: 44 VEFINCGKAVYSRVARVCKYDRGGPHRFRNRWTSFLKSRLNCSVPGD-FPF 93
EF + SR+ARVCK D GG + RWT+FLK++L CS+P D FPF
Sbjct: 209 KEFDFFENTIVSRIARVCKGDEGGERVLQKRWTTFLKAQLLCSLPDDGFPF 259
Sema4B, expressed in T and B cells, is an immune semaphorin. It functions as a negative regulatory of basophils through T cell-basophil contacts and it significantly inhibits IL-4 and IL-6 production from basophils in response to various stimuli, including IL-3 and papain. In addition, T cell-derived Sema4B suppresses basophil-mediated Th2 skewing and humoral memory responses. Sema4B may be also involved in lung cancer cell mobility by inducing the degradation of CLCP1 (CUB, LCCL-homology, coagulation factor V/VIII homology domains protein). Sema4B is characterized by a PDZ-binding motif at the carboxy-terminus, which mediates interaction with the post-synaptic density protein PSD-95/SAP90, which is thought to play a central role during synaptogenesis and in the structure and function of post-synaptic specializations of excitatory synapses. Sema4B belongs to class 4 transmembrane semaphorin family proteins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 464
>gnl|CDD|200520 cd11259, Sema_4D, The Sema domain, a protein interacting module, of semaphorin 4D (Sema4D, also known as CD100)
Sema4D/CD100 is expressed in immune cells and plays critical roles in immune response; it is thus termed an "immune semaphorin". It is expressed by lymphocytes and promotes the aggregation and survival of B lymphocytes and inhibits cytokine-induced migration of immune cells in vitro. Sema4D/CD100 knock-out mice demonstrate that Sema4D is required for normal activation of B and T lymphocytes. Sema4D increases B-cell and DC function using either Plexin B1 or CD72 as receptors. The function of Sema4D in immune response implicates its role in infectious and noninfectious diseases. Sema4D belongs to the class 4 transmembrane semaphorin family of proteins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 471
>gnl|CDD|200517 cd11256, Sema_4A, The Sema domain, a protein interacting module, of semaphorin 4A (Sema4A)
Sema4A is expressed in immune cells and is thus termed an "immune semaphorin". It plays critical roles in T cell-DC interactions in the immune response. It has been reported to enhance activation and differentiation of T cells in vitro and generation of antigen-specific T cells in vivo. The function of Sema4A in the immune response implicates its role in infectious and noninfectious diseases. Sema4A exerts its function through three receptors, namely Plexin B, Plexin D1, and Tim-2. Sema4A belongs to the class 4 transmembrane semaphorin family of proteins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. TThe Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 447
>gnl|CDD|200495 cd09295, Sema, The Sema domain, a protein interacting module, of semaphorins and plexins
Score = 78.8 bits (194), Expect = 9e-19
Identities = 39/96 (40%), Positives = 50/96 (52%), Gaps = 8/96 (8%)
Query: 2 DPIIYRE-----PLQTEQYDSMSLNAPNFVSSLTQG---DFVYFFFRETAVEFINCGKAV 53
P + R L+ S L+ FV + G D VYFFFR+ VE++ G
Sbjct: 144 RPALSRRSSNVHYLRIVVDSSTGLDEITFVYAFVSGDDDDEVYFFFRQEPVEYLKKGMVY 203
Query: 54 YSRVARVCKYDRGGPHRFRNRWTSFLKSRLNCSVPG 89
R+ARVCK D GG HR + + TSFLK+ LNCS P
Sbjct: 204 VPRIARVCKLDVGGCHRLKKKLTSFLKADLNCSRPQ 239
Both semaphorins and plexins have a Sema domain on their N-termini. Plexins function as receptors for the semaphorins. Evolutionarily, plexins may be the ancestor of semaphorins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems, and cancer. Semaphorins can be divided into 7 classes. Vertebrates have members in classes 3-7, whereas classes 1 and 2 are known only in invertebrates. Class 2 and 3 semaphorins are secreted; classes 1 and 4 through 6 are transmembrane proteins; and class 7 is membrane associated via glycosylphosphatidylinositol (GPI) linkage. Plexins are a large family of transmembrane proteins, which are divided into four types (A-D) according to sequence similarity. In vertebrates, type A plexins serve as co-receptors for neuropilins to mediate the signalling of class 3 semaphorins. Plexins serve as direct receptors for several other members of the semaphorin family: class 6 semaphorins signal through type A plexins and class 4 semaphorins through type B plexins. This family also includes the MET and RON receptor tyrosine kinases. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves to recognize and bind receptors. Length = 392
>gnl|CDD|200513 cd11252, Sema_3D, The Sema domain, a protein interacting module, of semaphorin 3D (Sema3D)
Sema3D is a secreted semaphorin expressed during the development of the nervous system. In zebrafish, Sema3D is expressed in the ventral tectum. It guides retinal axons along the dorsoventral axis of the tectum and guides the laterality of retinal ganglion cell (RGC) projections. Both Sema3D knockdown or its ubiquitous overexpression induced aberrant ipsilateral projections. Proper balance of Sema3D is needed at the midline for the progression of RGC axons from the chiasm midline into the contralateral optic tract. Sema3D is a member of the class 3 semaphorin family of proteins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 474
>gnl|CDD|200516 cd11255, Sema_3G, The Sema domain, a protein interacting module, of semaphorin 3G (Sema3G)
Score = 73.8 bits (181), Expect = 6e-17
Identities = 41/103 (39%), Positives = 58/103 (56%), Gaps = 11/103 (10%)
Query: 7 REPLQTEQYDSMSLNAPNFV-------SSLTQGDFVYFFFRETAVEF-INCGKAVYSRVA 58
R PL+TE D L+ P FV ++ D VYFFF E A E + A++SRV
Sbjct: 161 RSPLRTET-DQRLLHEPRFVAAHLIPDNADRDNDKVYFFFTERATETAEDDDGAIHSRVG 219
Query: 59 RVCKYDRGGPHRFRNRWTSFLKSRLNCSVPG--DFPFYFDEIQ 99
R+C D GG N+W++F+K+RL CSVPG +FD+++
Sbjct: 220 RLCANDAGGQRVLVNKWSTFIKARLVCSVPGPHGIQTHFDQLE 262
Semaphorin 3G is identified as a primarily endothelial cell- expressed class 3 semaphorin that controls endothelial and smooth muscle cell functions in autocrine and paracrine manners, respectively. It is mainly expressed in the lung and kidney, and a little in the brain. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 474
>gnl|CDD|200512 cd11251, Sema_3C, The Sema domain, a protein interacting module, of semaphorin 3C (Sema3C)
Sema3C is a secreted semaphorin expressed in and adjacent to cardiac neural crest cells, and causes impaired migration of neural crest cells to the developing cardiac outflow tract, resulting in the interruption of the aortic arch and persistent truncus arteriosus. It has been proposed that Sema3C acts as a guidance molecule, regulating migration of neural crest cells that express semaphorin receptors such as plexin A2. Sema3C may also participate in tumor progression. The cleavage of Sema3C induced by ADAMTS1 promotes the migration of breast cancer cells. Sema3C is a member of the class 3 semaphorin family of secreted proteins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 470
>gnl|CDD|200523 cd11262, Sema_4G, The Sema domain, a protein interacting module, of semaphorin 4G (Sema4G)
The Sema4G and Sema4C genes are expressed in the developing cerebellar cortex. Sema4G and Sema4C proteins specifically bind to Plexin B2 expressed in the cerebellar granule cells. Sema4G and Sema4C are involved in neural tube closure and cerebellar granule cell development through Plexin B2.Sema4G belongs to the class 4 transmembrane semaphorin family of proteins. Semaphorins are regulatory molecules involved in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 457
>gnl|CDD|200522 cd11261, Sema_4F, The Sema domain, a protein interacting module, of semaphorin 4F (Sema4F)
Score = 68.0 bits (166), Expect = 8e-15
Identities = 39/102 (38%), Positives = 53/102 (51%), Gaps = 15/102 (14%)
Query: 2 DPIIYREPLQTEQY----DSMS-LNAPNFVSSLT----------QGDFVYFFFRETAVEF 46
+PII R + E++ S LNAP FV+++ D +YFFF ETA E+
Sbjct: 148 EPIISRAVGRAEEWIRTETLPSWLNAPAFVAAVFLSPAEWGDEDGDDEIYFFFTETAREY 207
Query: 47 INCGKAVYSRVARVCKYDRGGPHRFRNRWTSFLKSRLNCSVP 88
+ + RVARVC D GG + RWT+FLK+ L C P
Sbjct: 208 DSYERIKVPRVARVCAGDLGGRKTLQQRWTTFLKADLLCPGP 249
Sema4F plays role in heterotypic cell-cell contacts and controls cell proliferation and suppresses tumorigenesis. In neurofibromatosis type 1 (NF1) patients, reduced Sema4F level disrupts Schwann cell/axonal interactions. Experiments using a yeast two-hybrid system show that the extreme C-terminus of Sema4F interacts with the PDZ domains of post-synaptic density protein SAP90/PSD-95, indicating possible functional involvement of Semas4F at glutamatergic synapses. Recent work also suggests a role for Sema4F in the injury response of intramedullary axotomized motoneuron. Sema4F belongs to the class 4 transmembrane semaphorin family of proteins. Semaphorins are regulator molecules involved in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 460
>gnl|CDD|200504 cd11243, Sema_7A, The Sema domain, a protein interacting module, of semaphorin 7A (Sema7A, also called CD108)
Score = 49.5 bits (118), Expect = 3e-08
Identities = 31/85 (36%), Positives = 43/85 (50%), Gaps = 10/85 (11%)
Query: 23 PNFVSSLT------QGDFVYFFFRETAVEFINCGKAVY-SRVARVCKYDRGG-PHRFRNR 74
P FV + D +Y+FFRE E SRVAR+CK D+GG ++
Sbjct: 151 PQFVKATLLPEDEQYQDKIYYFFREDN-EDKGPEAEPNISRVARLCKEDQGGTSSLSTSK 209
Query: 75 WTSFLKSRLNCSVPGDFPFYFDEIQ 99
W++FLK+RL C P P F+ +Q
Sbjct: 210 WSTFLKARLVCGDPAT-PMNFNRLQ 233
Sema7A plays regulatory roles in both immune and nervous systems. Unlike other semaphorins, which act as repulsive guidance cues, Sema7A enhances central and peripheral axon growth and is required for proper axon tract formation during embryonic development. Sema7A also plays a critical role in the negative regulation of T cell activation and function. Sema7A is a membrane-anchored member of the semaphorin family of proteins. Semaphorins are regulatory molecules in the development of the nervous system and in axonal guidance. They also play important roles in other biological processes, such as angiogenesis, immune regulation, respiration systems and cancer. The Sema domain is located at the N-terminus and contains four disulfide bonds formed by eight conserved cysteine residues. It serves as a receptor-recognition and -binding module. Length = 414
>PF01403 Sema: Sema domain; InterPro: IPR001627 The Sema domain occurs in semaphorins, which are a large family of secreted and transmembrane proteins, some of which function as repellent signals during axon guidance
Sema domains also occur in a hepatocyte growth factor receptor, in SEX protein [] and in viral proteins. CD100 (also called SEMA4D) is associated with PTPase and serine kinase activity. CD100 increases PMA, CD3 and CD2 induced T cell proliferation, increases CD45 induced T cell adhesion, induces B cell homotypic adhesion and down-regulates B cell expression of CD23. The Sema domain is characterised by a conserved set of cysteine residues, which form four disulphide bonds to stabilise the structure. The Sema domain fold is a variation of the beta propeller topology, with seven blades radially arranged around a central axis. Each blade contains a four- stranded (strands A to D) antiparallel beta sheet. The inner strand of each blade (A) lines the channel at the centre of the propeller, with strands B and C of the same repeat radiating outward, and strand D of the next repeat forming the outer edge of the blade. The large size of the Sema domain is not due to a single inserted domain but results from the presence of additional secondary structure elements inserted in most of the blades. The Sema domain uses a 'loop and hook' system to close the circle between the first and the last blades. The blades are constructed sequentially with an N-terminal beta- strand closing the circle by providing the outermost strand (D) of the seventh (C-terminal) blade. The beta-propeller is further stabilised by an extension of the N terminus, providing an additional, fifth beta-strand on the outer edge of blade 6 [, , ]. CD molecules are leucocyte antigens on cell surfaces. CD antigens nomenclature is updated at Protein Reviews On The Web (http://prow.nci.nih.gov/). ; GO: 0005515 protein binding; PDB: 3NVX_A 3NVQ_A 3OL2_A 1OLZ_B 3OKT_A 3AL9_B 3OKY_A 3AL8_B 3NVN_A 3OKW_A ....
