MAPキナーゼ不活性化に対するSte5スキャフォールドタンパク質の分離体の適合制御
Jesse G Zalatan1, Scott M Coyle, Saravanan Rajan
1Department of Cellular and Molecular Pharmacology, University of California, San Francisco, 600 16th Street, San Francisco, CA 94158, USA.
Science (New York, N.Y.)
|August 11, 2012
まとめ
イーストの骨組みタンパク質Ste5は,交配経路の誤通を隔離によってではなく,分子内相互作用によって防ぐ. フェロモン信号は,この自己抑制を放出し,交尾信号の伝送を可能にします.
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.
- シグナルトランスデュークション.
背景:
- 細胞は複数の経路でシグナル伝達タンパク質を利用し,クロストークのリスクを冒します.
- スキャフォールドタンパク質は,タンパク質セクステレーションによる誤通を防ぐために仮説化されている.
- イーストの交配ミトーゲン活性化タンパク質キナーゼ (MAPK) 経路は,Ste5・エスカフォルドタンパク質に依存しています.
研究 の 目的:
- Ste5スキャフォールドタンパク質が,酵母交配のMAPK経路における誤通信を防止するメカニズムを調査する.
- Ste5が封じ込めまたは他のメカニズムを使用して経路活動を調節するかどうかを判断する.
主な方法:
- Ste5タンパク質の相互作用と構成の分析.
- ステップ5.5における分子内相互作用の役割を調査する.
- フェロモンのシグナル伝達がSte5機能に与える影響を研究.
主要な成果:
- Ste5は,タンパク質連結による交配経路の活性化を防ぐことはできません.
- Ste5のプレックストリンホモロジー (PH) とフォン・ウィルブランド型A (VWA) ドメインの分子内相互作用は,基礎条件下でFus3 MAPKの活性化を阻害する.
- フェロモン誘発の膜結合は,この自己抑制を放出し,信号伝達を可能にします.
結論:
- Ste5は,交配経路の活動を制御するために,結合ではなく,形状的メカニズムを使用しています.
- Ste5はフェロモン信号の直接センサーとして作用し,交配のMAPK経路への信号伝送を調節します.
- このメカニズムは,酵母が交配反応を正確に制御することを保証します.
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