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Use of the Protease Fluorescent Detection Kit to Determine Protease Activity
Published on: August 4, 2009
SRCチロシンキナーゼの活性化ループフォスフォチロジンに対する分子認識役割の特定
Elizabeth J Videlock1, Victor K Chung, Justin M Hall
1Department of Chemistry, Yale University, New Haven, CT 06520, USA.
Journal of the American Chemical Society
|February 11, 2005
まとめ
フォスファディチルイノシトール-3キナーゼ (PI3K) のN端のSH2ドメインは,Srcチロシンキナーゼの活性化ループに結合する. Srcのリン酸化に依存するこの相互作用は,新しいタンパク質認識機構を明らかにします.
科学分野:
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
- 細胞シグナリング 細胞シグナリング
背景:
- キナーゼ活性化ループのリン酸化は通常,タンパク質とタンパク質の相互作用ではなく,酵素構成に影響します.
- Srcチロシンキナーゼは,細胞の信号伝達経路の重要な調節因子である.
- フォスファディチルイノシトール-3キナーゼ (PI3K) は,細胞の成長,増殖,生存において重要な役割を果たします.
研究 の 目的:
- キナーゼシグナル伝達に関与する新しいタンパク質相互作用ドメインを特定する.
- タンパク質認識における活性化ループのリン酸化の役割を調査する.
- SrcチロシンキナーゼとPI3Kの規制サブユニット間の相互作用を特徴付ける.
主な方法:
- Src活性化ループのフォスフォチロシンのフォスフォペプチド模倣を用いたファージディスプレイライブラリスクリーニング.
- 相互作用するタンパク質を隔離し,確認するためにアフィニティ染色体.
- 相互作用を検証するために,マウスの線維芽細胞における生化学的測定.
主要な成果:
- PI3Kのp85調節サブユニットのN端のSH2ドメインは,Src活性化ループフォスホペプチドの結合ドメインとして特定されました.
- 相互作用は,Src活性化ループのフォスフォチロジンに依存することが確認されました.
- 生化学的評価は,リン酸化Src活性化ループのN端SH2ドメインの特異性を実証した.
結論:
- Srcチロシンキナーゼの活性化ループのリン酸化は,直接のタンパク質-タンパク質認識を媒介することができます.
- PI3K p85サブユニットのN端のSH2ドメインは,リン酸化Src.を認識する役割を果たします.
- この発見は,タイロシンキナーゼとPI3Kを含む信号伝導の既知のメカニズムを拡張しています.
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