アンタゴニストは,cIAP1の構造変化を誘導し,その変化がオートウビキチネーションを促進する
Erin C Dueber1, Allyn J Schoeffler, Andreas Lingel
1Department of Early Discovery Biochemistry, Genentech, 1 DNA Way, South San Francisco, CA 94080, USA.
Science (New York, N.Y.)
|October 25, 2011
まとめ
アポトーシス阻害剤 (IAP) タンパク質は細胞死を調節する. 細胞IAP (cIAP) タンパク質への抗体結合はRING二酸化を誘発し,E3リガース活性を活性化し,細胞死を促進します.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- 細胞死亡規制 細胞死亡規制
背景:
- アポトーシス阻害剤 (IAP) タンパク質は,プログラム細胞死の主要な負の調節因子である.
- IAPファミリーのメンバーは,RINGドメインを通じてE3ユビキチンリガゼ活性を持っています.
- バキュロウイルス IAPリピート (BIR) ドメインと細胞IAP (cIAP) タンパク質に結合するアンタゴニストは,分解とアポトーシスを引き起こす.
- アンタゴニスト結合がRINGドメインの活性に影響するメカニズムは不明である.
研究 の 目的:
- cIAPタンパク質へのアンタゴニスト結合がE3リガース活性に影響する構造的および生化学的メカニズムを解明する.
- RINGドメインの活動は,全体的なcIAP構造によってどのように規制されているかを理解します.
主な方法:
- タンパク質の相互作用と酵素活性を研究するための生化学的測定法.
- タンパク質の構成を決定するために,おそらくX線結晶学や冷凍EMを含む構造研究.
主要な成果:
- 結合していないcIAP1はコンパクトモノマーとして存在し,RINGドメインを隔離し,その二分化を防止します.
- アンタゴニストの結合は,cIAP1.1内の構造変化を誘導する.
- これらの再配列はRINGドメインの二分化を促進し,活性E3ユビキチンリガゼ複合体の形成につながります.
結論:
- アンタゴニスト結合は,cIAP1 E3リゲーゼ活性に対する自己抑制を緩和する重要なアロステリックイベントです.
- この発見は,誘導された形状の変化と二分化によるE3リガース活性化の新しいメカニズムを明らかにしています.
- これは,IAPのタンパク質調節と潜在的な治療標的のより深い理解を提供します.
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