The desensitized channelrhodopsin-2 photointermediate contains 13 -cis, 15 -syn retinal Schiff base

  • Channelrhodopsin-2 (ChR2) is a light-gated cation channel and was used to lay the foundations of optogenetics. Its dark state X-ray structure has been determined in 2017 for the wild-type, which is the prototype for all other ChR variants. However, the mechanistic understanding of the channel function is still incomplete in terms of structural changes after photon absorption by the retinal chromophore and in the framework of functional models. Hence, detailed information needs to be collected on the dark state as well as on the different photointermediates. For ChR2 detailed knowledge on the chromophore configuration in the different states is still missing and a consensus has not been achieved. Using DNP-enhanced solid-state MAS NMR spectroscopy on proteoliposome samples, we unambiguously determined the chromophore configuration in the desensitized state, and we show that this state occurs towards the end of the photocycle.
Author:Johanna Becker-Baldus, Alexander Leeder, Lynda J. Brown, C. D. Brown, Christian Bamann, Clemens Glaubitz
Parent Title (German):Angewandte Chemie
Place of publication:Weinheim
Document Type:Article
Date of Publication (online):2021/05/11
Date of first Publication:2021/05/11
Publishing Institution:Universitätsbibliothek Johann Christian Senckenberg
Release Date:2022/04/05
Tag:channelrhodopsin; dynamic nuclear polarization; membrane proteins; photocycle; solid-state NMR spectroscopy
Page Number:6
First Page:16442
Last Page:16447
The work was funded by Deutsche Forschungs-gemeinschaft/Sonderforschungsbereich 807 Transport and Communications across Membranes. The dynamic nuclear polarization experiments were enabled through DFG Equipment Grant GL 307/4-1 and the Cluster of Excellence Frankfurt: Macromolecular Complexes Frankfurt. Work at the Center for Biomolecular Magnetic Resonance is supported by the State of Hesse. Open access funding enabled and organized by Projekt DEAL.
Institutes:Biochemie, Chemie und Pharmazie
Wissenschaftliche Zentren und koordinierte Programme / Zentrum für Biomolekulare Magnetische Resonanz (BMRZ)
Dewey Decimal Classification:5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften
5 Naturwissenschaften und Mathematik / 57 Biowissenschaften; Biologie / 570 Biowissenschaften; Biologie
Licence (German):License LogoCreative Commons - Namensnennung 4.0