7L1E

The Crystal Structure of Bromide-Bound GtACR1

7L1E の概要

• エントリーDOI: 10.2210/pdb7l1e/pdb
• 分子名称: Anion channelrhodopsin-1, BROMIDE ION, (2R)-2,3-dihydroxypropyl (9Z)-octadec-9-enoate, ... (5 entities in total)
• 機能のキーワード: bromide-bound, anion tunnel, anion channel, rhodopsin, transport protein
• 由来する生物種: Guillardia theta (Cryptophyte, Cryptomonas phi)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 63629.85

構造登録者

Li, H.,Huang, C.Y.,Wang, M.,Spudich, J.L.,Zheng, L. (登録日: 2020-12-14, 公開日: 2021-05-26, 最終更新日: 2023-10-18)

主引用文献

Li, H.,Huang, C.Y.,Govorunova, E.G.,Sineshchekov, O.A.,Yi, A.,Rothschild, K.J.,Wang, M.,Zheng, L.,Spudich, J.L.
The crystal structure of bromide-bound Gt ACR1 reveals a pre-activated state in the transmembrane anion tunnel.
Elife, 10:-, 2021

PubMed Abstract: The crystal structure of the light-gated anion channel ACR1 reported in our previous Research Article (Li et al., 2019) revealed a continuous tunnel traversing the protein from extracellular to intracellular pores. We proposed the tunnel as the conductance channel closed by three constrictions: C1 in the extracellular half, mid-membrane C2 containing the photoactive site, and C3 on the cytoplasmic side. Reported here, the crystal structure of bromide-bound ACR1 reveals structural changes that relax the C1 and C3 constrictions, including a novel salt-bridge switch mechanism involving C1 and the photoactive site. These findings indicate that substrate binding induces a transition from an inactivated state to a pre-activated state in the dark that facilitates channel opening by reducing free energy in the tunnel constrictions. The results provide direct evidence that the tunnel is the closed form of the channel of ACR1 and shed light on the light-gated channel activation mechanism.

PubMed: 33998458
DOI: 10.7554/eLife.65903

実験手法

X-RAY DIFFRACTION (3.2 Å)