Aqp1
Domain
Aquaporins contain two tandem repeats each containing three membrane-spanning domains and a pore-forming loop with the signature motif Asn-Pro-Ala (NPA).
Function
Forms a water channel that facilitates the transport of water across cell membranes, playing a crucial role in water homeostasis in various tissues. Could also be permeable to small solutes including hydrogen peroxide, glycerol and gases such as amonnia (NH3), nitric oxide (NO) and carbon dioxide (CO2). Recruited to the ankyrin-1 complex, a multiprotein complex of the erythrocyte membrane, it could be part of a CO2 metabolon, linking facilitated diffusion of CO2 across the membrane, anion exchange of Cl(-)/HCO3(-) and interconversion of dissolved CO2 and carbonic acid in the cytosol. In vitro, it shows non-selective gated cation channel activity and may be permeable to cations like K(+) and Na(+) in vivo.
Sequence Similarities
Belongs to the MIP/aquaporin (TC 1.A.8) family.
Tissue Specificity
Erythrocytes and renal tubules.
Cellular localization
- Cell membrane
- Multi-pass membrane protein
Alternative names
Chip28, Aqp1, Aquaporin-1, AQP-1, Aquaporin-CHIP