4ILC

The GLIC pentameric ligand-gated ion channel in complex with sulfates

4ILC の概要

• エントリーDOI: 10.2210/pdb4ilc/pdb
• 関連するPDBエントリー: 4HFI 4IL4 4IL9 4ILA 4ILB
• 分子名称: Proton-gated ion channel, ACETATE ION, DIUNDECYL PHOSPHATIDYL CHOLINE, ... (9 entities in total)
• 機能のキーワード: pentameric ligand-gated ion channel, ion channel, membrane, membrane protein, transport protein
• 由来する生物種: Gloeobacter violaceus
• 細胞内の位置: Cell inner membrane; Multi-pass membrane protein (Probable): Q7NDN8
• タンパク質・核酸の鎖数: 5
• 化学式量合計: 192832.33

構造登録者

Sauguet, L.,Malherbe, L.,Corringer, P.J.,Delarue, M. (登録日: 2012-12-29, 公開日: 2013-02-20, 最終更新日: 2023-09-20)

主引用文献

Sauguet, L.,Poitevin, F.,Murail, S.,Van Renterghem, C.,Moraga-Cid, G.,Malherbe, L.,Thompson, A.W.,Koehl, P.,Corringer, P.J.,Baaden, M.,Delarue, M.
Structural basis for ion permeation mechanism in pentameric ligand-gated ion channels.
Embo J., 32:728-741, 2013

PubMed Abstract: To understand the molecular mechanism of ion permeation in pentameric ligand-gated ion channels (pLGIC), we solved the structure of an open form of GLIC, a prokaryotic pLGIC, at 2.4 Å. Anomalous diffraction data were used to place bound anions and cations. This reveals ordered water molecules at the level of two rings of hydroxylated residues (named Ser6' and Thr2') that contribute to the ion selectivity filter. Two water pentagons are observed, a self-stabilized ice-like water pentagon and a second wider water pentagon, with one sodium ion between them. Single-channel electrophysiology shows that the side-chain hydroxyl of Ser6' is crucial for ion translocation. Simulations and electrostatics calculations complemented the description of hydration in the pore and suggest that the water pentagons observed in the crystal are important for the ion to cross hydrophobic constriction barriers. Simulations that pull a cation through the pore reveal that residue Ser6' actively contributes to ion translocation by reorienting its side chain when the ion is going through the pore. Generalization of these findings to the pLGIC family is proposed.

PubMed: 23403925
DOI: 10.1038/emboj.2013.17

実験手法

X-RAY DIFFRACTION (2.99 Å)