c-SrcとHckのSH2とSH3ドメインのダイナミックなカップリングは,C端のチロシンリン酸化によるそれらの不活性化に基礎を置いている
M A Young1, S Gonfloni, G Superti-Furga
1Laboratories of Molecular Biophysics, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA.
Cell
|April 13, 2001
まとめ
Srcキナーゼのリン酸化
科学分野:
- バイオケミストリーと分子生物学
- 細胞シグナル伝達 細胞信号伝達
- タンパク質キナーゼの研究
背景:
- Srcキナーゼは,細胞信号伝達経路の重要なレギュレーターです.
- 彼らの活動は,SH2とSH3を含む規制ドメインによって厳しく制御されています.
- C末端のチロシンリン酸化は,Srcキナーゼの活性を調節する上で重要な役割を果たします.
研究 の 目的:
- Hck キナーゼとc-Src キナーゼの分子動態に対するC端のチロシンリン酸化の影響を調査する.
- キナーゼ活性化を調節するSH2-SH3コネクタの役割を明らかにする.
- 尾のリン酸化がドメインカップリングに影響を与えるメカニズムを理解するために.
主な方法:
- 分子ダイナミクスシミュレーションは,Hckとc-Srcキナーゼの行動を研究するために使用されました.
- C端末の脱リン酸化とSH2-SH3コネクターの変異の効果をシミュレートした.
- 酵母 Schizosaccharomyces pombe.でc-Srcの変異分析が行われました.
主要な成果:
- 不活性なSrcキナーゼのSH2およびSH3ドメインは,コネクタによって緊密に結合され,活性化を阻害します.
- C端尾の脱酸化により,SH2-SH3ドメインの結合が減少する.
- SH2-SH3コネクタをグリシンで変異させると,c-Srcが活性化され,規制的な役割が示唆される.
結論:
- SH2-SH3コネクタは,誘導可能な"スナップロック"メカニズムとして機能します.
- 尾性リン酸化は,SH2およびSH3ドメインを締め付け,キナーゼの不活性性を維持する.
- 尾のリン酸化の放出により,柔軟性が認められ,キナーゼの活性化が促進されます.
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