MAPキナーゼによって媒介されるc-junのリン酸化
B J Pulverer1, J M Kyriakis, J Avruch
1Ludwig Institute for Cancer Research, London, UK.
Nature
|October 17, 1991
まとめ
この研究は,ミトゲン活性化タンパク質 (MAP) キナーゼがc-junタンパク質の特定の部位をリン酸化し,その活性性を高めることを明らかにしています. このリン酸化メカニズムは,様々な成長信号がc-jun転写因子を活性化する方法を説明しています.
科学分野:
- 分子生物学は分子生物学である.
- 細胞シグナル伝達 細胞信号伝達
- 腫瘍生成 (オンコゲネシス) について
背景:
- プロトオンコゲンc-junは,核現象を調節する転写因子である.
- c-junの活動は,リン酸化,特にカルボキシ末端での脱リン酸化によって調節されます.
- フォルボールのエステルを含む細胞外刺激は,c-jun活性に影響する.
研究 の 目的:
- ミトゲンによって調節されるc-junの特定のリン酸化部位を特定する.
- c-jun酸化におけるミトゲン活性化タンパク質 (MAP) キナーゼの役割を調査する.
- MAPキナーゼ媒介のリン酸化がc-junの転写活動にどのように影響するかを決定する.
主な方法:
- c-jun.のリン酸化部位のマッピング
- 純化されたMAPキナーゼを用いたインビトロキナーゼアッセイ (pp54,pp42/44).
- リン酸化後のc-junトランザクティベーション活動の分析.
主要な成果:
- c-jun amino-terminal A1ドメインの2つのセリン残基は,リン酸化の標的として特定されました.
- ミトゲン,ホルボールのエステル,および活性化されたラスは,これらの部位でリン酸化を誘導する.
- MAPキナーゼ pp54とpp42/44は,これらのセリン残基を特にリン酸化し,c-junトランザクティベーションが増加します.
結論:
- A1ドメインの特定のセリン残基のMAPキナーゼ媒介のリン酸化により,c-junの活性が正に調節される.
- このメカニズムは,ミトゲン,成長因子,および腫瘍遺伝子が一般的にc-jun.をどのように刺激するかについての洞察を提供します.
- この発見は,成長信号に対する細胞の反応における重要な規制経路を強調しています.
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