ZAP-70のチロシンキナーゼ活性抑制の構造的基礎
Sebastian Deindl1, Theresa A Kadlecek, Tomas Brdicka
1Department of Molecular and Cell Biology, Department of Chemistry, and Howard Hughes Medical Institute, University of California, Berkeley, CA 94720, USA.
Cell
|May 22, 2007
まとめ
ZAP-70キナーゼの活性化には,明確な自己抑制メカニズムが含まれています. T細胞の調節部とキナーゼドメインの間の相互作用を不安定化させることは,T細胞受容体シグナル伝達を開始するための鍵です.
科学分野:
- 分子生物学は分子生物学である.
- 免疫学 免疫学とは
- 構造生物学 構造生物学とは
背景:
- ZAP-70 (ゼータ鎖関連タンパク質キナーゼ70) は,T細胞抗原受容体 (TCR) 信号伝達における重要な細胞質チロシンキナーゼである.
- その活動は,免疫受容体チロシンベースの活性化モチーフ (ITAM) に結合するタンデムSH2ドメインを含むセグメントによって調節されます.
研究 の 目的:
- ZAP-70自己抑制の構造的基礎を解明する.
- T細胞シグナル伝達におけるZAP-70活性化のメカニズムを理解する.
主な方法:
- 自己抑制されたZAP-70の結晶構造を決定した.
- 規制セグメントとキナーゼ領域内の相互作用を分析した.
主要な成果:
- 不活性なZAP-70キナーゼドメインは,CDKとSrcキナーゼに似た構造を採用しています.
- 自動阻害は,制御セグメントとヒンジ領域の間のユニークな相互作用を含み,キナーゼの柔軟性を減少させます.
- SH2-キナーゼリンカー内の酸化可能なチロシン残基は,アロマティック-アロマティック相互作用に参加し,ITAM結合を阻害します.
結論:
- ZAP-70の自己抑制メカニズムは,他のキナーゼと異なる.
- これらのアロマ相互作用の破壊による自己抑制型構造の不安定化は,ZAP-70の活性化における最初のステップである可能性が高い.
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