Proton transfer reactions in the red light-activatable channelrhodopsin variant ReaChR and their relevance for its function.

ABSTRACT: Channelrhodopsins (ChRs) are light-gated ion channels widely used for activating selected cells in large cellular networks. ChR variants with a red-shifted absorption maximum, such as the modified Volvox carteri ChR1 red-activatable channelrhodopsin ("ReaChR," λ_max = 527 nm), are of particular interest because longer wavelengths allow optical excitation of cells in deeper layers of organic tissue. In all ChRs investigated so far, proton transfer reactions and hydrogen bond changes are crucial for the formation of the ion-conducting pore and the selectivity for protons versus cations, such as Na⁺, K⁺, and Ca²⁺ (1). By using a combination of electrophysiological measurements and UV-visible and FTIR spectroscopy, we characterized the p

SUBMITTER: Kaufmann JCD 

PROVIDER: S-EPMC5572910 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature