RNF168は,H2A/H2AX上でK13-15をユビキチネートし,DNA損傷シグナル伝達を推進する
Francesca Mattiroli1, Joseph H A Vissers, Willem J van Dijk
1Division of Biochemistry and Center for Biomedical Genetics, Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.
Cell
|September 18, 2012
まとめ
RNF168は,RNF8ではなく,DNA損傷応答中にK13-15のヒストンH2A/H2AXをモノビキチナートする. この特定のヒストンのユビキチネーションは,ユビキチンの鎖だけでなく,信号伝送に不可欠です.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- バイオケミストリー バイオケミストリー
背景:
- 二重鎖断裂 (DSB) に対するDNA損傷反応 (DDR) は,ユビキチン依存のシグナル伝達を含む.
- RNF8とRNF168は,ヒストンH2AとH2AXをターゲットにすることで,この反応を開始する重要なE3リガゼです.
研究 の 目的:
- DDR中のヒストンのユビキチン化におけるRNF8とRNF168の特定の役割を解明する.
- DSBシグナリングに含まれる正確なオビキチネーションサイトとチェーンリンクを決定する.
主な方法:
- RNF8とRNF168RINGドメインの構造ベースの変異.
- DSBサイトにおけるヒストンのユビキチネーションパターン (モノウビキチネーションとK63結合鎖) の分析.
- ヒストンをターゲットにすることができない変異RNF168を用いた機能評価.
主要な成果:
- RNF8は核群H2Aに対して無活性であり,RNF168はK13-15.5でH2A/H2AXのモノウビキチネーションを触媒化する.
- RINGドメインの充電された残基は,RNF8/RNF168.8.によって核細胞タンパク質の認識を決定する.
- K63のユビキチン鎖は,K118-119ではなく,K13-15でRNF168依存のモノウビキチン化と結合している.
- ユビキチン鎖を触媒するだけでなくヒストンを標的とするRNF168の能力は,DDRシグナル伝達に不可欠です.
結論:
- RNF168は,DSB修復中のK13-15におけるH2A/H2AX単一ビキチン化に起因する主要なE3リガゼである.
- RNF168による特定のヒストンのユビキチン化は,ユビキチン鎖の形成のみから独立して,下流のDDRシグナル伝達の前提条件である.
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