A Gate Hinge Controls the Epithelial Calcium Channel TRPV5.

ABSTRACT: TRPV5 is unique within the large TRP channel family for displaying a high Ca²⁺ selectivity together with Ca²⁺-dependent inactivation. Our study aims to uncover novel insights into channel gating through in-depth structure-function analysis. We identify an exceptional tryptophan (W583) at the terminus of the intracellular pore that is unique for TRPV5 (and TRPV6). A combination of site-directed mutagenesis, biochemical and electrophysiological analysis, together with homology modeling, demonstrates that W583 is part of the gate for Ca²⁺ permeation. The W583 mutants show increased cell death due to profoundly enhanced Ca²⁺ influx, resulting from altered channel function. A glycine residue above W583 might act as flexible linker to rearrange the try

SUBMITTER: van der Wijst J 

PROVIDER: S-EPMC5379628 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature