Protein-coding gene in the species Homo sapiens
Transient receptor potential cation channel subfamily V member 5 is a calcium channel protein that in humans is encoded by the TRPV5 gene.[5][6][7]
Function
The TRPV5 gene is a member of the transient receptor family and the TRPV subfamily. The calcium-selective channel, TRPV5, encoded by this gene has 6 transmembrane-spanning domains, multiple potential phosphorylation sites, an N-linked glycosylation site, and 5 ANK repeats. This protein forms homotetramers or heterotetramers and is activated by a low internal calcium level.[8]
Both TRPV5 and TRPV6 are expressed in kidney and intestinal epithelial cells.[9] TRPV5 is mainly expressed in kidney epithelial cells, where it plays an important role in the reabsorption of Ca2+,[10] whereas TRPV6 is mainly expressed in the intestine.[9] The enzyme α-klotho increases kidney calcium reabsorption by stabilizing TPRV5.[9] Klotho is a beta-glucuronidase-like enzyme that activates TRPV5 by removal of sialic acid.[11]
Clinical significance
Normally, about 95% to 98% of Ca2+ filtered from the blood by the kidney is reabsorbed by the kidney's renal tubule, mediated by TRPV5.[12] Genetic deletion of TRPV5 in mice leads to Ca2+ loss in the urine, and consequential hyperparathyroidism, and bone loss.[13]
Interactions
TRPV5 has been shown to interact with S100A10.[15]