Redox regulation of K_V7 channels through EF3 hand of calmodulin.

ABSTRACT: Neuronal K_V7 channels, important regulators of cell excitability, are among the most sensitive proteins to reactive oxygen species. The S2S3 linker of the voltage sensor was reported as a site-mediating redox modulation of the channels. Recent structural insights reveal potential interactions between this linker and the Ca²⁺-binding loop of the third EF-hand of calmodulin (CaM), which embraces an antiparallel fork formed by the C-terminal helices A and B, constituting the calcium responsive domain (CRD). We found that precluding Ca²⁺ binding to the EF3 hand, but not to EF1, EF2, or EF4 hands, abolishes oxidation-induced enhancement of K_V7.4 currents. Monitoring FRET (Fluorescence Resonance Energy Transfer) between helices A and B using purified C

SUBMITTER: Nunez E 

PROVIDER: S-EPMC9988260 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature