段階分離は,遺伝子体核細胞のユビキチン化を指示する
Laura D Gallego1, Maren Schneider1, Chitvan Mittal2
1Max Perutz Labs, Medical University of Vienna, Vienna Biocenter Campus (VBC), Vienna, Austria.
Nature
|March 28, 2020
まとめ
イーストのBre1およびRad6酵素は,液体-液体相分離を使用してヒストンH2Bをモノビキチナートする. このプロセスはクロマチンの反応室を作り,遺伝子体のユビキチネーションを高め,潜在的に人間の神経疾患に影響を与えます.
科学分野:
- 分子生物学
- エピジェネティクス
- 生物化学
背景:
- ヒストンH2Bモノビキチネーションは,Bre1 (E3ユビキチンリガゼ) とRad6 (E2酵素) によって触媒される遺伝子転写に不可欠である.
- Bre1とRad6が遺伝子体全体でプロセス的なH2Bのユビキチネーションを達成するメカニズムは,まだ十分に理解されていません.
- 以前のモデルでは 酵素がRNAポリメラーゼIIと共に 移動する可能性があると示唆していましたが これは観察されたパターンを完全に説明できません
研究 の 目的:
- 遺伝子体におけるヒストンH2Bのユビキチネーションのメカニズムを解明する.
- H2Bのユビキチネーションプロセスにおける液体-液体相分離の役割を調査する.
- クロマチン関連酵素が 触媒活性を増やす方法を理解する
主な方法:
- Bre1-Rad6-Lge1システムの生化学的再構成
- 脚架タンパク質Lge1の相分離特性解析
- 酵母遺伝子を用いて,Lge1の凝縮物形成領域の機能を評価する in vivo 研究.
主要な成果:
- 脚本タンパク質Lge1は,液体-液体相分離を駆動し,Bre1で層状の凝縮物を形成する.
- これらの凝縮物はRad6と核細胞基板を誘導し,H2Bのユビキチン化を著しく加速する.
- Lge1の凝縮物形成領域は,生体内では+1核素を超えたH2Bのユビキチン化に不可欠である.
結論:
- ヒストン修正酵素の層状の凝縮物は,クロマチン関連反応室として作用し,遺伝子ボディに沿って触媒的活動を強化します.
- この相分離メカニズムは,転写中の表遺伝子調節に関する新しい理解を提供します.
- 人間の細胞における相分離の障害は 神経学的疾患と関連付けられる.
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