Rik1-Dos2複合体によるDNA複製とヒストンの改変の調整
Fei Li1, Rob Martienssen, W Zacheus Cande
1Department of Biology, New York University, New York, New York 10003, USA. fl43@nyu.edu
Nature
|July 5, 2011
まとめ
分裂酵母は,DNA複製中にヘテロクロマチンを維持するためにRNA干渉を使用します. 新しく特定された複合体は,DNA複製をヒストンのメチル化と結び付け,エピジェネティック継承を保証する.
科学分野:
- エピジェネティクス エピジェネティクス
- 分子生物学は分子生物学である.
- クロマチンの生物学
背景:
- ヒストンの改変マークは,染色体プロセスにおいて極めて重要です.
- DNA複製中のヒストンマークの正確な遺伝は,まだ十分に理解されていません.
- 分裂酵母はRNA干渉 (RNAi) を利用して,細胞周期調節によるヒストンの甲基化を行う.
研究 の 目的:
- 核分裂酵母における新種の静音化複合体を特徴づけるために.
- ヘテロクロマチン調節とDNA複製における複合体の役割を調査する.
- DNA複製とエピジェネティックマークの伝播の間の分子関連を解明する.
主な方法:
- Dos2,Rik1,Mms19,Cdc20を含む静音複合体の特性について
- ヘテロクロマチン内のRNAポリメラーゼIIの活性分析.
- 複合体のDNA複製とヘテロクロマチン組成に対する要求の評価.
主要な成果:
- Dos2,Rik1,Mms19,Cdc20を含む新しいサイレンスコンプレックスが特定されました.
- この複合体は,ヘテロクロマチンにおけるRNAポリメラーゼIIの活性を調節する.
- この複合体は,分裂酵母におけるDNA複製とヘテロクロマチン組成に不可欠である.
結論:
- 特定された複合体は,DNA複製とヒストンのメチル化との間の分子リンクを提供する.
- この発見は,細胞サイクル中の表遺伝子マーク伝播のメカニズムに光を当てています.
- この過程を理解することは,代々どのようにエピジェネティック状態が遺伝されるかを理解する鍵です.
関連する概念動画
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In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.
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