極のT1インターフェースは,電圧ゲートされたカリウムチャネルを開く構造変化と関連しています
D L Minor1, Y F Lin, B C Mobley
1Howard Hughes Medical Institute and Department of Physiology, University of California, San Francisco 94143, USA. minor@itsa.ucsf.edu
Cell
|September 28, 2000
まとめ
電圧ゲート型カリウムチャネル (Kv) はゲート化のためにT1ドメインに依存しています. 変異とドメイン置換実験によって示されたように,極性T1表面の構造の変化は,チャネル開通に不可欠です.
科学分野:
- 分子生物学は分子生物学である.
- バイオフィジックス 生物物理学
- イオンチャネル機能のイオンチャネル機能
背景:
- Kv電圧ゲートカリウムチャネルは,細胞の電気信号伝送に不可欠です.
- サイトプラズマのT1ドメインは,KVチャネル組立に関与することが知られている.
- 以前の研究では,ゲーティングにおけるT1の役割が示唆されていたが,直接的な構造的証拠は欠けていた.
研究 の 目的:
- KvチャネルゲーティングメカニズムにおけるT1ドメインの直接的関与を調査する.
- チャンネル構成の変化におけるT1の役割の構造的基礎を解明する.
主な方法:
- Kv1.2 T1領域内の特定の残留物のサイト指向型変異.
- 構造的影響と機能的変化を評価するためのイソステル変異分析.
- テトラメリックコイルドコイルを使用したドメイン置換実験.
主要な成果:
- 哺乳類のKv1.2チャネルのゲーティングは,極界面内の補完的なT1表面の残留物に依存しています.
- このインターフェースのイソステリック変異は構造をわずかに変えたが,閉じたチャネルとT1テトラメアを安定させた.
- T1ドメインをテトラメリックコイルドコイルで置き換えると,閉じたチャネル状態が不安定になります.
結論:
- 埋もれた極性T1表面内の構造的再配置は,KVチャネルゲートに不可欠です.
- T1ドメインの構造は,チャネル開通に必要な形状の変化に直接影響を与えます.
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Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several types of...
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