小型のGTP結合タンパク質racは,成長因子誘発の膜乱れを調節する
A J Ridley1, H F Paterson, C L Johnston
1Institute for Cancer Research, Chester Beatty Laboratories, London, England.
Cell
|August 7, 1992
まとめ
ラスタンパク質は,生長因子誘発の膜ラッフリングと線維芽細胞のアクチン組織に不可欠です. これらのrasに関連するGTP結合タンパク質は,成長因子信号をrhoタンパク質経由でアクチンダイナミクスとリンクします.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
背景:
- RacなどのRas関連のGTP結合タンパク質は,細胞シグナル伝達において重要な役割を果たします.
- アクチン細胞骨格組織は,細胞の構造と機能の基本です.
- 成長因子信号伝達経路は,アクチンダイナミクスを含む多様な細胞プロセスを調節する.
研究 の 目的:
- 線維芽細胞におけるRacタンパク質の機能を調査する.
- 成長因子によるアクチン再構成におけるRacの役割を決定する.
- Rac,Rho,およびアクチン細胞骨格のダイナミクスの関係を解明する.
主な方法:
- スイスの3T3線維芽細胞にRac1と支配的な抑制性N17Rac1変異体の微注射.
- 成長因子による刺激と活性化されたH-ras.
- アクチンフィラメントの蓄積,膜のラッフリング,およびストレス繊維の形成の観察.
主要な成果:
- Rac1のマイクロインジェクションは,アクチンフィラメントの蓄積と膜のラッフリングを急速に誘導しました.
- 成長因子に誘発された膜乱れはN17Rac1によって遮断され,Rac依存性を示した.
- 成長因子はRacを利用して,ストレス繊維形成のためのRho依存の経路を活性化します.
結論:
- 内生 Rac タンパク質は,成長因子誘発の膜乱れのために必要である.
- RacとRhoのタンパク質は,成長因子をアクチン組織と結びつける信号伝達経路で機能する.
- RacとRhoは,ポリメリ化アクチンの調節に不可欠な成分です.
関連する概念動画
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