%0 Journal Article
%A Bestsennaia, Ekaterina
%A Maslov, Ivan
%A Balandin, Taras
%A Alekseev, Alexey
%A Yudenko, Anna
%A Abu Shamseye, Assalla
%A Zabelskii, Dmitrii
%A Baumann, Arnd
%A Catapano, Claudia
%A Karathanasis, Christos
%A Gordeliy, Valentin
%A Heilemann, Mike
%A Gensch, Thomas
%A Borshchevskiy, Valentin
%T Channelrhodopsin‐2 Oligomerization in Cell Membrane Revealed by Photo‐Activated Localization Microscopy
%J Angewandte Chemie
%V 63
%N 11
%@ 1433-7851
%C Weinheim
%I Wiley-VCH
%M FZJ-2024-01648
%P e202307555
%D 2024
%X Microbialrhodopsinsare retinalmembraneproteinsthat founda broadapplicationin optogenetics.Theoligomericstate of rhodopsinsis importantfor their functionalityand stability.Of particularinterestis the oligomericstate in the cellularnativemembraneenvironment.Fluorescencemicroscopyprovidespowerfultools to determinetheoligomericstate of membraneproteinsdirectlyin cells. Amongthese methodsis quantitativephotoactivatedlocalizationmicroscopy(qPALM)allowingthe investigationof molecularorganizationat the level of singleproteinclusters.Here,we applyqPALMto investigatethe oligomericstate of the first and most used optogenetictool Channelrhodopsin-2(ChR2)in the plasmamembraneof eukaryoticcells. ChR2appearedpredominantlyas a dimerin the cell membraneanddid not form higheroligomers.The disulfidebondsbetweenCys34and Cys36of adjacentChR2monomerswere notrequiredfor dimerformationand mutationsdisruptingthese bondsresultedin only partialmonomerizationof ChR2.The monomericfractionincreasedwhenthe total concentrationof mutantChR2in the membranewas low. Thedissociationconstantwas estimatedfor this partiallymonomerizedmutantChR2as 2.2�0.9 proteins/μm2. Our findingsare importantfor understandingthe mechanisticbasis of ChR2activityas well as for improvingexistingand developingfutureoptogenetictools.
%F PUB:(DE-HGF)16
%9 Journal Article
%$ 38226794
%U <Go to ISI:>//WOS:001155410200001
%R 10.1002/anie.202307555
%U https://juser.fz-juelich.de/record/1023075