Racは成長因子誘発型アラキドン酸の放出を媒介する
M P Peppelenbosch1, R G Qiu, A M de Vries-Smits
1Laboratory for Physiological Chemistry Utrecht University, The Netherlands.
Cell
|June 16, 1995
まとめ
成長因子は,RacとRhoタンパク質を通したストレス繊維の形成を誘発し,白血球トリエンの生成を伴う. この研究では,Racは,ストレス繊維の組み立てに不可欠な,表皮成長因子誘発性白血球菌にとって重要であることが明らかになりました.
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:
- 成長因子信号伝達経路は,細胞骨格の動態を調節する.
- ストレス繊維の形成は,細胞の結合と移動に不可欠です.
- RacおよびRhoタンパク質は,アクチン細胞骨格の重要な調節因子である.
研究 の 目的:
- 成長因子誘発のストレス繊維形成におけるRac,Rho,およびルオコトリエン生成の関係を解明する.
- このシグナリングカスケードにおけるRacと白血球トリエンの特定の役割を特定する.
主な方法:
- 皮質成長因子 (EGF) によって誘発されたアラキドン酸の産生におけるRacの役割を調査した.
- EGFと構成的に活性なRac変異体 (Rac V12) に反応した白血球生成を分析した.
- ストレス繊維形成のための白血球トリエンの必要性と十分性を評価し,Rhoタンパク質の必要性を評価した.
主要な成果:
- Racは,EGF誘発によるアラキドン酸の産生と,その後の白血球トリエンの生成に不可欠です.
- 構成的に活性であるRac V12は,成長因子とは無関係に白血球トリエンを生成する.
- EGFまたはRac V12によって生成される白内素は,ストレス繊維形成に必要かつ十分である.
- レウコトリエンに依存するストレス繊維の形成には,Rhoタンパク質が必要です.
結論:
- 成長因子受容体からのシグナル伝達経路を特定し,Rac,アラキドン酸の産生,白血球トリエンの合成,およびRho活性化を含む.
- この経路は,RacがRho依存型細胞骨格の再編成に影響を与える主なメカニズムです.
- レウコトリエンは,RacとRho依存のストレス繊維形成において重要な媒介者として作用する.
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