Aquaporin-6 (AQP6)

Aquaporin-6 (AQP6) is a member of the aquaporin membrane protein family and is encoded by the AQP6 gene in humans. It is predominantly expressed in intracellular vesicles within renal epithelial cells and less commonly found at the plasma membrane. While most aquaporins function as selective water channels, AQP6 is notable for its ability to transport anions (such as nitrate and chloride) in response to acidic pH and to partially function as a water channel. Its physiological significance includes participation in renal acid–base homeostasis and possibly in processes like glomerular filtration and endocytosis in the kidney. It is activated by mercurial compounds and exhibits unique amino acid substitutions affecting transport selectivity, making it biochemically distinct within the major intrinsic protein (MIP) family. There are currently no established disease indications or clinical therapeutics targeting AQP6, but it is of interest for antibody-based detection and research on renal epithelial cell function.

Other names

Aquaporin-2-likeKidney-specific aquaporinhKIDAQP2LKIDAquaporin-6

Mercury ions (Hg²⁺) activate AQP6, increasing its anion channel permeability; amino acid mutations (e.g., N60G) can switch its specificity from anion to water channel