インテグリン活性化の抑制:Ras/Rafが誘発するMAPキナーゼ経路の新たな機能
P E Hughes1, M W Renshaw, M Pfaff
1Department of Vascular Biology, The Scripps Research Institute, La Jolla, California 92037, USA.
Cell
|February 21, 1997
まとめ
この研究では,H-RasとRaf-1は,重要な細胞粘着プロセスであるインテグリン活性化を否定的に調節することを明らかにしました. この調節は転写独立であり,ERK MAP キナーゼ経路と関連しており,新しいフィードバックメカニズムを示唆しています.
科学分野:
- 細胞結合生物学 細胞結合生物学
- シグナルトランスデュークション
- 分子細胞生物学 分子細胞生物学
背景:
- インテグリンは重要な細胞粘着受容体であり,リンガンド結合親和性を迅速に調節し,この過程を活性化と呼びます.
- インテグリン活性化の調節を理解することは,細胞-細胞および細胞-マトリックス相互作用を理解するために不可欠です.
研究 の 目的:
- インテグリン活性化の新たなレギュレータを特定する.
- インテグリン親近性調節の基礎となる分子メカニズムを解明する.
主な方法:
- インテグリン活性化の抑制剤のスクリーンを実施しました.
- H-Rasとそのエフェクターキナーゼ,Raf-1.の役割を調査しました.
- インテグリンリン酸化,mRNA転写,タンパク質合成への影響を評価した.
- ERK MAP キナーゼ経路の活性化と相関する抑制.
主要な成果:
- インテグリン活性化の負の調節体としてH-RasとRaf-1を特定した.
- H-Rasが,異なるサブユニットの組み合わせでインテグリン活性化を抑制することを実証した.
- 抑制はインテグリンリン酸化,転写,タンパク質合成とは無関係であることが判明した.
- H-Ras媒介抑制とERK MAPキナーゼ経路の活性化との相関が示されました.
結論:
- インテグリン親和状態は,Ras-リンクされたMAPキナーゼ経路の新しい,転写独立機能によって調節されます.
- この経路は,H-RasとERK MAPキナーゼを含み,インテグリン機能における負のフィードバックループとして作用する可能性があります.
- 細胞粘着を制御する複雑なシグナル伝達ネットワークに関する新しい洞察を提供します.
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