9GO2

C1C2 Channelrhodopsin - SMX Light activated structure

9GO2 の概要

• エントリーDOI: 10.2210/pdb9go2/pdb
• 分子名称: Archaeal-type opsin 1,Archaeal-type opsin 2, (2R)-2,3-dihydroxypropyl (9Z)-octadec-9-enoate, RETINAL, ... (4 entities in total)
• 機能のキーワード: channelrhodopsin, light-activated, membrane protein
• 由来する生物種: Chlamydomonas reinhardtii (Chlamydomonas smithii); 詳細
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 40935.28

構造登録者

Mulder, M.,Weinert, T.,Skopintsev, P.,Bruenle, S.,Broser, M.,Hegemann, P.,Standfuss, J. (登録日: 2024-09-04, 公開日: 2025-01-29)

主引用文献

Mulder, M.,Hwang, S.,Broser, M.,Brunle, S.,Skopintsev, P.,Schattenberg, C.,Schnick, C.,Hartmann, S.,Church, J.,Schapiro, I.,Dworkowski, F.,Weinert, T.,Hegemann, P.,Sun, H.,Standfuss, J.
Structural Insights Into the Opening Mechanism of C1C2 Channelrhodopsin.
J.Am.Chem.Soc., 147:1282-1290, 2025

PubMed Abstract: Channelrhodopsins, light-gated cation channels, enable precise control of neural cell depolarization or hyperpolarization with light in the field of optogenetics. This study integrates time-resolved serial crystallography and atomistic molecular dynamics (MD) simulations to resolve the structural changes during C1C2 channelrhodopsin activation. Our observations reveal that within the crystal environment, C1C2 predominantly remains in a light-activated state with characteristics of the M intermediate. Here, rearrangement of retinal within its binding pocket partially opens the central gate toward the extracellular vestibule. These structural changes initiate channel opening but were insufficient to allow K flow. Adjusting protonation states to represent the subsequent N intermediate in our MD simulations induced further conformational changes, including rearrangements of transmembrane helices 2 and 7, that opened the inner gate and the putative ion-translocation pathway. This allowed spontaneous cation conduction with low conductance, aligning with experimental findings. Our findings provide critical structural insights into key intermediates of the channel opening mechanism, enhancing our understanding of ion conduction and selectivity in channelrhodopsins at an atomistic level.

PubMed: 39680650
DOI: 10.1021/jacs.4c15402

実験手法

X-RAY DIFFRACTION (2.7 Å)