パドルモチーフ機能の持ち運び性と,電圧センサーの薬理学
Abdulrasheed A Alabi1, Maria Isabel Bahamonde, Hoi Jong Jung
1Molecular Physiology and Biophysics Section, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892, USA.
Nature
|November 16, 2007
まとめ
膜タンパク質の重要なモチーフである電圧センサーパドルは,異なる種とタンパク質タイプで一貫して機能します. この保存されたモジュールは,毒素と薬物開発の重要なターゲットです.
科学分野:
- バイオフィジックス 生物物理学
- 分子生物学は分子生物学である.
- 構造生物学 構造生物学とは
背景:
- 電圧感知ドメイン (VSD) は,膜タンパク質が電圧変化を検知するために不可欠です.
- 多様なタンパク質のVSDメカニズムの保存は,毛穴ドメインのないタンパク質を含む,依然として不明確です.
研究 の 目的:
- 電圧センサーのパドルモチーフの保存された機能とモジュール性を調査するために.
- パドルモチーフがタンパク質間で転送されたときに,電圧ゲートチャネル機能を駆動できるかどうかを判断する.
- 毒素がパドルモチーフと相互作用し,その影響が電圧センサーの活性化に及ぼす影響を調査する.
主な方法:
- KvAP,HV1およびCi-VSPからの電圧センサーパドルモチーフ (S3bおよびS4ヘリク) を真核のカリウムチャネルに移植する.
- パドルモチーフの移植がチャネルゲートに及ぼす機能的影響を評価する.
- タンパク質-脂質界面のパドルモチーフ機能に対するタランチュラ毒素の影響を調査.
主要な成果:
- 移植されたパドルモチーフは,真核系チャネルにおける脱極化時にチャネル開通を成功させた.
- 膜に分解する毒素は,パドルモチーフと相互作用し,両方のチャネルとVSDタンパク質の電圧センサーの活性化を混乱させた.
- パドルモチーフは,異なるタンパク質の文脈でモジュラリティと保存された機能を実証しました.
結論:
- 電圧センサーパドルは,VDS内のモジュラーで保存された機能ユニットです.
- パドルモチーフは,脂質膜環境内で動作し,相対的な移動の自由を示します.
- ボルテージセンサーパドルは,薬理学的介入の重要かつ薬物投与可能なターゲットです.
関連する概念動画
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