Trafficking mechanism of water channel aquaporin‐2

Abstract

Targeted positioning of the water channel AQP2 (aquaporin‐2) strictly regulates body water homoeostasis. Trafficking of AQP2 to the apical membrane is critical for the reabsorption of water in renal collecting ducts. In addition to the cAMP‐mediated effect of vasopressin on AQP2 trafficking to the apical membrane, other signalling cascades can also induce this sorting. Recently, AQP2‐binding proteins which could regulate this trafficking have been discovered; SPA‐1 (signal‐induced proliferation‐associated gene‐1), a GAP (GTPase‐activating protein) for Rap1, and the cytoskeletal protein actin. This review summarizes recent advances related to the trafficking mechanisms of AQP2.