Score = 57.8 bits (138), Expect = 2e-08, Method: Composition-based stats.
Identities = 29/69 (42%), Positives = 40/69 (57%)
Query: 11 LTPADFQGNLGLTTLNKHLTPVQGMGIEFFLGFVLVLVIFGVCDGNKPHAKAPAALAIGL 70
+TP G LG+TT++ +LT G+ +E + F LV IF CD + ALAIG
Sbjct: 136 VTPPSVVGGLGVTTVHGNLTAGHGLLVELIITFQLVFTIFASCDSKRTDVTGSVALAIGF 195
Query: 71 TVALGHLAA 79
+VA+GHL A
Sbjct: 196 SVAIGHLFA 204
Forms a water-specific channel. Osmoreceptor which regulates body water balance and mediates water flow within the central nervous system. It is expressed predominantly in the ependymal cell lining the aqueductal system and over the space of the brain in contact with the subarachnoid space, as cerebrospinal fluid fills these structures it may facilitate water balance between brain parenchyma and the fluid compartment. In the plasma membranes of the neurons of the paraventricular and supraoptic nuclei, it may mediate rapid changes in cell volume in response to local shifts in extracellular osmolarity.
Forms a water-specific channel. May be involved in the transfer of excess sap dietary water from the initial midgut to the terminal midgut and the proximal part of the malpighian tubules.
>gi|91078198|ref|XP_968342.1| PREDICTED: similar to aquaporin [Tribolium castaneum] gi|270002357|gb|EEZ98804.1| hypothetical protein TcasGA2_TC001374 [Tribolium castaneum]
Score = 49.2 bits (118), Expect = 9e-09
Identities = 20/71 (28%), Positives = 28/71 (39%), Gaps = 1/71 (1%)
Query: 10 ALTPADFQGNLGLTTLNKHLTPVQGMGIEFFLGFVLVLVIFGVCDGNKPHAKAP-AALAI 68
+T + +L + Q +E L F LV +F D + + A LAI
Sbjct: 104 GVTNGLQRAGGFANSLAPGVNAGQAFVVEIILTFQLVYTVFATTDDPRNGSLGHVAPLAI 163
Query: 69 GLTVALGHLAA 79
G V L HLA
Sbjct: 164 GFAVFLNHLAG 174
MIP (Major Intrinsic Protein) family proteins exhibit essentially two distinct types of channel properties: (1) specific water transport by the aquaporins, and (2) small neutral solutes transport, such as glycerol by the glycerol facilitators. Length = 218
>gnl|CDD|238204 cd00333, MIP, Major intrinsic protein (MIP) superfamily
Score = 46.9 bits (112), Expect = 6e-08
Identities = 23/71 (32%), Positives = 32/71 (45%), Gaps = 1/71 (1%)
Query: 9 QALTPADFQGNLGLTTLNKHLTPVQGMGIEFFLGFVLVLVIFGVCD-GNKPHAKAPAALA 67
+ L + + T + ++ +EF F+LVLV+F D N P A LA
Sbjct: 107 EFLGANNIVAGIFGTYPSPGVSNGNAFFVEFIGTFILVLVVFATTDDPNGPPPGGLAPLA 166
Query: 68 IGLTVALGHLA 78
IGL VA LA
Sbjct: 167 IGLLVAAIGLA 177
Members of the MIP superfamily function as membrane channels that selectively transport water, small neutral molecules, and ions out of and between cells. The channel proteins share a common fold: the N-terminal cytosolic portion followed by six transmembrane helices, which might have arisen through gene duplication. On the basis of sequence similarity and functional characteristics, the superfamily can be subdivided into two major groups: water-selective channels called aquaporins (AQPs) and glycerol uptake facilitators (GlpFs). AQPs are found in all three kingdoms of life, while GlpFs have been characterized only within microorganisms. Length = 228
>gnl|CDD|233156 TIGR00861, MIP, MIP family channel proteins
Score = 43.1 bits (102), Expect = 2e-06
Identities = 26/72 (36%), Positives = 33/72 (45%), Gaps = 2/72 (2%)
Query: 10 ALTPADFQGNLGLTTLNKH-LTPVQGMGIEFFLGFVLVLVIFGVCDGNKPHAKAP-AALA 67
LT F GNL + ++ Q +EF +LVLVIF D + A LA
Sbjct: 99 GLTSGLFPGNLAVNGSASAGVSSGQAFFVEFIGTAILVLVIFATTDDRNRVPRGGFAPLA 158
Query: 68 IGLTVALGHLAA 79
IGL V L HL+
Sbjct: 159 IGLLVFLIHLSM 170
1.A.8 The Major Intrinsic Protein (MIP) FamilyThe MIP family is large and diverse, possessing over 100 members that all form transmembrane channels. These channel proteins function in water, smallcarbohydrate (e.g., glycerol), urea, NH3, CO2 and possibly ion transport by an energy independent mechanism. They are found ubiquitously in bacteria, archaeaand eukaryotes. The MIP family contains two major groups of channels: aquaporins and glycerol facilitators.The known aquaporins cluster loosely together as do the known glycerol facilitators. MIP family proteins are believed to form aqueous pores that selectively allow passive transport of their solute(s) across the membrane with minimal apparent recognition. Aquaporins selectively transport water (but not glycerol) while glycerol facilitators selectively transport glycerol but not water. Some aquaporins can transport NH3 and CO2. Glycerol facilitators function as solute nonspecific channels, and may transport glycerol, dihydroxyacetone, propanediol, urea and other small neutral molecules in physiologically importantprocesses. Some members of the family, including the yeast FPS protein (TC #1.A.8.5.1) and tobacco NtTIPA may transport both water and small solutes [Transport and binding proteins, Unknown substrate]. Length = 216
>gnl|CDD|223653 COG0580, GlpF, Glycerol uptake facilitator and related permeases (Major Intrinsic Protein Family) [Carbohydrate transport and metabolism]
>PF00230 MIP: Major intrinsic protein; InterPro: IPR000425 A number of transmembrane (TM) channel proteins can be grouped together on the basis of sequence similarities [, , , , ]
These include: Mammalian major intrinsic protein (MIP). MIP is the major component of lens fibre gap junctions. Mammalian aquaporins []. These proteins form water- specific channels that provide the plasma membranes of red cells and kidney prox imal and collecting tubules with high permeability to water, thereby permitting water to move in the direction of an osmotic gradient. Soybean nodulin-26, a major component of the peribacteroid membrane induced during nodulation in legume roots after Rhizobium infection. Plants tonoplast intrinsic proteins (TIP). There are various isoforms of TIP : alpha (seed), gamma, Rt (root), and Wsi (water-stress induced). These proteins may allow the diffusion of water, amino acids and/or peptides from the tonoplas t interior to the cytoplasm. Bacterial glycerol facilitator protein (gene glpF), which facilitates the mo vement of glycerol across the cytoplasmic membrane. Salmonella typhimurium propanediol diffusion fac ilitator (gene pduF). Yeast FPS1, a glycerol uptake/efflux facilitator protein. Drosophila neurogenic protein 'big brain' (bib). This protein may mediate in tercellular communication; it may functions by allowing the transport of certain molecules(s) and thereby sending a signal for an exodermal cell to become an ep idermoblast instead of a neuroblast. Yeast hypothetical protein YFL054c. A hypothetical protein from the pepX region of Lactococcus lactis. The structures of various members of the MIP family have been determined by means of X-ray diffraction [, , ], revealing the fold to comprise a right-handed bundle of 6 transmembrane (TM) alpha-helices [, , ]. Similarities in the N-and C-terminal halves of the molecule suggest that the proteins may have arisen through tandem, intragenic duplication of an ancestral protein that contained 3 TM domains []. Some of the proteins in this group are responsible for the molecular basis of the blood group antigens, surface markers on the outside of the red blood cell membrane. Most of these markers are proteins, but some are carbohydrates attached to lipids or proteins []. Aquaporin-CHIP (Aquaporin 1) belongs to the Colton blood group system and is associated with Co(a/b) antigen.; GO: 0005215 transporter activity, 0006810 transport, 0016020 membrane; PDB: 3NE2_A 2C32_A 1YMG_A 2B6P_A 3C02_A 2B5F_D 3CN6_A 3CN5_A 1Z98_M 3CLL_A ....
>COG0580 GlpF Glycerol uptake facilitator and related permeases (Major Intrinsic Protein Family) [Carbohydrate transport and metabolism]
Members of the MIP superfamily function as membrane channels that selectively transport water, small neutral molecules, and ions out of and between cells. The channel proteins share a common fold: the N-terminal cytosolic portion followed by six transmembrane helices, which might have arisen through gene duplication. On the basis of sequence similarity and functional characteristics, the superfamily can be subdivided into two major groups: water-selective channels called aquaporins (AQPs) and glycerol uptake facilitators (GlpFs). AQPs are found in all three kingdoms of life, while GlpFs have been characterized only within microorganisms.
Members of the MIP superfamily function as membrane channels that selectively transport water, small neutral molecules, and ions out of and between cells. The channel proteins share a common fold: the N-terminal cytosolic portion followed by six transmembrane helices, which might have arisen through gene duplication. On the basis of sequence similarity and functional characteristics, the superfamily can be subdivided into two major groups: water-selective channels called aquaporins (AQPs) and glycerol uptake facilitators (GlpFs). AQPs are found in all three kingdoms of life, while GlpFs have been characterized only within microorganisms.
processes. Some members of the family, including the yeast FPS protein (TC #1.A.8.5.1) and tobacco NtTIPA may transport both water and small solutes.
>PF00230 MIP: Major intrinsic protein; InterPro: IPR000425 A number of transmembrane (TM) channel proteins can be grouped together on the basis of sequence similarities [, , , , ]
These include: Mammalian major intrinsic protein (MIP). MIP is the major component of lens fibre gap junctions. Mammalian aquaporins []. These proteins form water- specific channels that provide the plasma membranes of red cells and kidney prox imal and collecting tubules with high permeability to water, thereby permitting water to move in the direction of an osmotic gradient. Soybean nodulin-26, a major component of the peribacteroid membrane induced during nodulation in legume roots after Rhizobium infection. Plants tonoplast intrinsic proteins (TIP). There are various isoforms of TIP : alpha (seed), gamma, Rt (root), and Wsi (water-stress induced). These proteins may allow the diffusion of water, amino acids and/or peptides from the tonoplas t interior to the cytoplasm. Bacterial glycerol facilitator protein (gene glpF), which facilitates the mo vement of glycerol across the cytoplasmic membrane. Salmonella typhimurium propanediol diffusion fac ilitator (gene pduF). Yeast FPS1, a glycerol uptake/efflux facilitator protein. Drosophila neurogenic protein 'big brain' (bib). This protein may mediate in tercellular communication; it may functions by allowing the transport of certain molecules(s) and thereby sending a signal for an exodermal cell to become an ep idermoblast instead of a neuroblast. Yeast hypothetical protein YFL054c. A hypothetical protein from the pepX region of Lactococcus lactis. The structures of various members of the MIP family have been determined by means of X-ray diffraction [, , ], revealing the fold to comprise a right-handed bundle of 6 transmembrane (TM) alpha-helices [, , ]. Similarities in the N-and C-terminal halves of the molecule suggest that the proteins may have arisen through tandem, intragenic duplication of an ancestral protein that contained 3 TM domains []. Some of the proteins in this group are responsible for the molecular basis of the blood group antigens, surface markers on the outside of the red blood cell membrane. Most of these markers are proteins, but some are carbohydrates attached to lipids or proteins []. Aquaporin-CHIP (Aquaporin 1) belongs to the Colton blood group system and is associated with Co(a/b) antigen.; GO: 0005215 transporter activity, 0006810 transport, 0016020 membrane; PDB: 3NE2_A 2C32_A 1YMG_A 2B6P_A 3C02_A 2B5F_D 3CN6_A 3CN5_A 1Z98_M 3CLL_A ....
