Srcファミリーキナーゼ基質p130Casの機械的な拡張による力感知
Yasuhiro Sawada1, Masako Tamada, Benjamin J Dubin-Thaler
1Department of Biological Sciences, Columbia University, Sherman Fairchild Center Room 715, MC-2416, 1212 Amsterdam Avenue, New York, NY 10027, USA. ys454-ind@umin.ac.jp
Cell
|November 30, 2006
まとめ
細胞の力感知が明確にされる:p130Cas (Cas) タンパク質は,機械的ストレス下で拡張し,そのリン酸化を高め,下流の信号伝達経路を活性化します. これは,Casが物理的な力の重要なセンサーであることを明らかにしています.
科学分野:
- 細胞生物学 細胞生物学
- バイオフィジックス 生物物理学
- 分子シグナリング
背景:
- 物理的な力の細胞感知は,多くの生物学的プロセスに不可欠ですが,まだ十分に理解されていません.
- 以前の研究では,p130Cas (Cas) が力依存シグナル伝達,特に小さなGTPase Rap1.1の活性化に関与していた.
研究 の 目的:
- p130Cas (Cas) のリン酸化における機械力の役割を調査する.
- Cas拡張が細胞における力伝導のメカニズムであるかどうかを判断する.
主な方法:
- 細菌で発現するカス基板領域タンパク質 (CasSD) の機械的な拡張 in vitro.
- Srcファミリーキナーゼを用いた酸化測定法.
- 免疫光顕微鏡では,拡張されたCasSD.を認識する新しい抗体を使用して,無傷の細胞で免疫光顕微鏡を用います.
主要な成果:
- CasSDの in vitro 機械的な拡張により,Src 族キナーゼによるリン酸化が著しく強化されました.
- 拡張されたCasSDを認識する抗体は,広がる細胞の周辺部でCas拡張を検出した.
- これらの領域は,高い牽引力とリン酸化Casと関連しており,生理学的関連性を示しています.
結論:
- p130 カス (Cas) は,物理力の主要なセンサーとして作用します.
- フォーストランスデュークションは,Casの機械的な拡張を伴うため,そのリン酸化と,その後下流の信号伝達経路の活性化が開始されます.
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