電圧ゲート型ナトリウムチャネルの結晶構造
Jian Payandeh1, Todd Scheuer, Ning Zheng
1Department of Pharmacology, University of Washington, Seattle, Washington 98195, USA.
Nature
|July 12, 2011
まとめ
電圧ゲートされたナトリウムチャネル (NavAb) の結晶構造は,その閉孔構造を明らかにします. この原子レベルでの理解は,イオン選択性と刺激性の高い細胞における薬物ブロックメカニズムを説明します.
科学分野:
- 構造生物学 構造生物学とは
- バイオフィジックス 生物物理学
- 分子薬理学 分子薬理学
背景:
- ボルテージゲートナトリウムチャネル (Na(V)) は,興奮性細胞の電気信号伝達に不可欠です.
- 活性化,イオン選択性,および薬物相互作用を制御するそれらの正確な原子構造は,ほとんど不明のままである.
- Na(V) 経路の構造を理解することは,神経学的および心臓病の治療法の開発に不可欠です.
研究 の 目的:
- 高解像度のナトリウムチャネルの結晶構造を測定する.
- 電圧依存活性化,イオン選択性,薬物結合の構造的基礎を解明する.
- Na (V) チャンネル機能と薬理学を理解するための構造的なテンプレートを提供すること.
主な方法:
- 2.7 Å の解像度のX線結晶学.
- 閉孔状態のアルコバクター・ブツレリ (Arcobacter butzleri) の電圧ゲートナトリウムチャネル (NavAb) の構造分析.
- カリウムチャネルによる比較構造分析.
主要な成果:
- NavAbチャネル構造は,閉孔形状の活性化された電圧センサーを明らかにします.
- アルギニンゲーティング電荷は,電圧センサー内の重要な水性相互作用を形成します.
- 短くて狭い選択性フィルターと酸性サイドチェーンは,高フィールド強度のアニオン部位を通じたNa (((+)) 選択性を授与します.
- 毛孔モジュールの窓口は,水害性の薬物の侵入を可能にします.
結論:
- 決定された構造は,電圧ゲートされたナトリウムチャネルの前例のない原子詳細を提供します.
- この発見は,Na(+) の選択性を説明し,潜在的な薬物結合部位を明らかにする.
- この構造的なテンプレートは,電気信号と関連疾患の理解を深めていきます.
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