RAD6媒介の転写結合H2Bユビキチレーションは,ヒト細胞におけるH3K4メチレーションを直接刺激する
Jaehoon Kim1, Mohamed Guermah, Robert K McGinty
1The Rockefeller University, New York, NY 10065, USA.
Cell
|May 5, 2009
まとめ
この研究は,ヒトのRAD6を,遺伝子転写に不可欠なH2Bの汎用化のためのE2酵素として識別しています. このプロセスがH3K4メチル化を刺激し,遺伝子発現の調節に影響を与える方法を明らかにしています.
科学分野:
- 分子生物学は分子生物学である.
- エピジェネティクス エピジェネティクス
- 遺伝子規制 遺伝子規制
背景:
- H2Bの汎用化は,活性転写と関連しているが,ヒト細胞におけるそのメカニズムは不明である.
- hBRE1は以前,ヒト細胞におけるH2Bのユビキチル化に責任を負うE3リガゼとして特定されていた.
研究 の 目的:
- ヒト細胞におけるH2Bの普遍化のためのE2結合酵素を特定する.
- トランスクリプション中のH2Bの普遍化のメカニズムを解明する.
- トランスクリプションとヒストンの改変に対するH2B普遍化の機能的影響を決定する.
主な方法:
- タンパク質の相互作用を評価するための共免疫プレシピテーション.
- クロマチン免疫降水 (ChIP) は,遺伝子へのタンパク質の徴集を分析する.
- ウェスタン・ブロッティングは,ヒストンのユビキティレーション状態とメチレーション状態を検出します.
主要な成果:
- hRAD6は,H2Bの汎用化のためのE2結合酵素として特定されました.
- hRAD6はhBRE1と直接相互作用し,転写された遺伝子に採用されます.
- リスイン120におけるH2Bの普遍化は,hPAF媒介の転写に依存している.
- H2Bの普遍化は,hSET1依存のH3K4の二,三メチル化を刺激する.
- H2Bの普遍化は,hPAF,SII,p300によって媒介される転写レベルに直接影響を及ぼさない.
結論:
- この研究は,ヒトの細胞におけるH2Bの普遍化のための重要な要因とメカニズムを確立しています.
- H2Bのユビキチテレーションは,転写開始と延長の後方に作用します.
- このユビキティレーションイベントは,下流のエピジェネティック変異,特にH3K4メチレーションを調節する上で重要な役割を果たします.
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