タンパク質キナーゼ rafによってMAPキナーゼ経路の活性化
L R Howe1, S J Leevers, N Gómez
1Chester Beatty Laboratories, Institute of Cancer Research, London, England.
Cell
|October 16, 1992
まとめ
この研究は,RAFタンパク質キナーゼがMAPキナーゼの上流に作用することを明らかにしています. Rafは,信号伝達経路の重要な成分として特定され,潜在的にMAPキナーゼキナーゼキナーゼまたはキナーゼキナーゼキナーゼである可能性があります.
科学分野:
- 細胞の信号伝達経路は,
- タンパク質キナーゼの相互作用
- 腫瘍遺伝子の研究
背景:
- ミトゲン活性化タンパク質 (MAP) キナーゼおよびp74raf-1タンパク質キナーゼは,成長因子および腫瘍性p21ras.によって活性化されます.
- MAPキナーゼとRAFシグナリングの正確な関係は,完全に解明されていません.
研究 の 目的:
- MAPキナーゼとRAFタンパク質キナーゼの関係を調査する.
- MAPキナーゼシグナリングカスケード内のRAFの位置を決定する.
主な方法:
- MAPキナーゼERK2の活性化が,腫瘍学的に活性化されたRAFによって研究されている.
- 過剰発現したp74raf-1によるERK2活性化の強化を調査した.
- p74raf-1.によって不活性化されたMAPキナーゼキナーゼの再活性化を評価した.
主要な成果:
- 腫瘍性RAF発現は,MAPキナーゼERK2を細胞の反応から独立して活性化する.
- 過剰発現したp74raf-1は,EGFとTPAによって誘発されたERK2の活性化を高めます.
- 治療された細胞から免疫的に誘発されたp74raf-1は,フォスファタゼで不活性化されたMAPキナーゼキナーゼを活性化します.
結論:
- Rafタンパク質キナーゼは,細胞シグナル伝達において,MAPキナーゼより上流で機能する.
- RafはMAPキナーゼキナーゼキナーゼまたはMAPキナーゼキナーゼキナーゼキナーゼとして提案されています.
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