1.A.4.2.10
TRPV5 epithelial Ca²⁺ channel (ECaC1) (forms homo- and heterotetrameric channels with TRPV6; requires the S100A10-annexin 2 complex for routing to the plasma membrane) (Hoenderop et al., 2003; van de Graaf et al., 2003).  The kidney maintains whole body calcium homoeostasis due to the reabsorption of Ca²⁺ filtered by the kidney glomerulus. TRPV5 regulates urinary Ca²⁺ excretion by mediating active Ca²⁺ reabsorption in the distal convoluted tubule of the kidney. The histidine kinase, nucleoside diphosphate kinase B (NDPK-B), activates TRPV5 channel activity and Ca²⁺ flux, and this activation requires histidine 711 in the carboxy terminal tail of TRPV5. In addition, the histidine phosphatase, protein histidine phosphatase 1 (PHPT1), inhibits NDPK-B activated TRPV5 (Cai et al. 2014).  TRPV5 also transports cadmium (Cd²⁺). The L530R mutation is associated with recurrent kidney stones (Wang et al. 2017).  May be stabilized by Mucin-1 (Muc1; P15941) (Al-Bataineh et al. 2017). TRPV5 inhibitors have been identified (Hughes et al. 2019). A modular and reusable model of epithelial transport in the proximal convoluted tubuleof the kidney has appeared (Noroozbabaee et al. 2022).