活性化されたCdc42はc-Cblを隔離し,EGF受容体の分解を防ぐ
Wen Jin Wu1, Shine Tu, Richard A Cerione
1Department of Molecular Medicine, Veterinary Medical Center, Baker Laboratory, Cornell University, Ithaca, NY 14853, USA.
Cell
|September 25, 2003
まとめ
Cdc42の活性化は,c-CblによるEGF受容体のユビキチネーションを防止し,これは細胞成長の調節における重要なステップである. 不調は,持続的なシグナル伝達と細胞の変容につながります.
科学分野:
- 細胞生物学 細胞生物学
- 分子シグナル伝達です.
- がん研究 がん研究
背景:
- Rasに関連するタンパク質であるCdc42は,細胞の成長を調節し,細胞の変容に関与しています.
- 皮膜成長因子 (EGF) 信号伝達には,EGF受容体とc-Cblユビキチンリガゼが関与しています.
- これらの経路の異常な調節は,制御不能な細胞増殖につながる可能性があります.
研究 の 目的:
- EGF受容体の活性を調節するCdc42の役割を調査する.
- Cdc42がEGF受容体ユビキチン化に影響を与える分子メカニズムを解明する.
- Cdc42の調節不良が細胞の変容にどのように寄与するかを理解する.
主な方法:
- 活性化されたCdc42とp85Cool-1/beta-Pix.の相互作用を調査しました.
- EGF受容体へのc-Cblの結合に対するCdc42の影響を評価した.
- 持続的なシグナリング効果を研究するために,構成的に活性なCdc42 (Cdc42(F28L)) を利用しました.
主要な成果:
- 活性化されたCdc42はp85Cool-1/beta-Pixと結合し,c-CblによるEGF受容体のユビキチン化を阻害する.
- この阻害は,EGF受容体の負の調節を防ぐ.
- 構成的に活性なCdc42は,EGF受容体の持続的なシグナル伝達とERK活性化につながり,細胞の変容を促進します.
結論:
- Cdc42は,EGF受容体-c-Cbl相互作用のタイミングに重要な役割を果たしています.
- Cdc42は,c-Cbl媒介による分解に対するEGF受容体の保護因子として作用する.
- Cdc42によるこの調節軸の乱れは,腫瘍形成に寄与する.
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