Aqp2 phospho S269
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-specific channel that provides the plasma membranes of renal collecting duct with high permeability to water, thereby permitting water to move in the direction of an osmotic gradient (PubMed:7508187, PubMed:8429910). Plays an essential role in renal water homeostasis (By similarity). Could also be permeable to glycerol (By similarity).
Post-translational modifications
Ser-256 phosphorylation is necessary and sufficient for expression at the apical membrane. Endocytosis is not phosphorylation-dependent.
N-glycosylated.
Sequence Similarities
Belongs to the MIP/aquaporin (TC 1.A.8) family.
Tissue Specificity
Detected in kidney, in cortical and the medullary collecting tubules (at protein level) (PubMed:8429910). Detected in kidney medulla and cortex (PubMed:7508187, PubMed:8429910).
Cellular localization
- Apical cell membrane
- Multi-pass membrane protein
- Basolateral cell membrane
- Multi-pass membrane protein
- Cell membrane
- Multi-pass membrane protein
- Cytoplasmic vesicle membrane
- Multi-pass membrane protein
- Golgi apparatus
- trans-Golgi network membrane
- Multi-pass membrane protein
- Shuttles from vesicles to the apical membrane. Vasopressin-regulated phosphorylation is required for translocation to the apical cell membrane. PLEKHA8/FAPP2 is required to transport AQP2 from the TGN to sites where AQP2 is phosphorylated.
Alternative names
Aquaporin-2, AQP-2, ADH water channel, Aquaporin-CD, Collecting duct water channel protein, WCH-CD, Water channel protein for renal collecting duct, AQP-CD, Aqp2