2FY8

Crystal structure of MthK rck domain in its ligand-free gating-ring form

2FY8 の概要

• エントリーDOI: 10.2210/pdb2fy8/pdb
• 関連するPDBエントリー: 1LNQ 2AEF 2AEJ 2AEM
• 分子名称: Calcium-gated potassium channel mthK (2 entities in total)
• 機能のキーワード: transport, ionic channel, alternative initiation, transmembrane, ion transport, potassium, potassium transport, membrane, gating ring, closed conformation, partially open conformation, transition state, transport protein
• 由来する生物種: Methanothermobacter thermautotrophicus
• 細胞内の位置: Cell membrane; Multi-pass membrane protein: O27564
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 203576.00

構造登録者

Ye, S.,Jiang, Y. (登録日: 2006-02-07, 公開日: 2006-09-05, 最終更新日: 2023-08-30)

主引用文献

Ye, S.,Li, Y.,Chen, L.,Jiang, Y.
Crystal Structures of a Ligand-free MthK Gating Ring: Insights into the Ligand Gating Mechanism of K(+) Channels.
Cell(Cambridge,Mass.), 126:1161-1173, 2006

PubMed Abstract: MthK is a prokaryotic Ca(2+)-gated K(+) channel that, like other ligand-gated channels, converts the chemical energy of ligand binding to the mechanical force of channel opening. The channel's eight ligand-binding domains, the RCK domains, form an octameric gating ring in which Ca(2+) binding induces conformational changes that open the channel. Here we present the crystal structures of the MthK gating ring in closed and partially open states at 2.8 A, both obtained from the same crystal grown in the absence of Ca(2+). Furthermore, our biochemical and electrophysiological analyses demonstrate that MthK is regulated by both Ca(2+) and pH. Ca(2+) regulates the channel by changing the equilibrium of the gating ring between closed and open states, while pH regulates channel gating by affecting gating-ring stability. Our findings, along with the previously determined open MthK structure, allow us to elucidate the ligand gating mechanism of RCK-regulated K(+) channels.

PubMed: 16990139
DOI: 10.1016/j.cell.2006.08.029

実験手法

X-RAY DIFFRACTION (2.79 Å)