ヘテロクロマチン内の再結合修復には,ATPに依存したクロマチンの改造が必要です
Manisha Sinha1, Shinya Watanabe, Aaron Johnson
1University of Massachusetts Medical School, Worcester, MA 01605, USA.
Cell
|September 22, 2009
まとめ
酵母ヘテロクロマチンのサータンパク質は,同種の再結合を抑制する. SWI/SNFのようなクロマチンリモデレータは,この抑制を克服し,DNA修復プロセスを促進することができます.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- クロマチン生物学 クロマチン生物学
背景:
- ヘテロクロマチンは,同種の再結合を阻害することにより,染色体の完全性を維持するために重要である.
- Sir2p,Sir3p,Sir4pは,Saccharomyces cerevisiaeのヘテロクロマチンの重要な構造成分であり,テロメアと静かな交配型ロシオに位置しています.
研究 の 目的:
- ミニ染色体内のSirタンパク質が,再結合修復の初期段階をin vitroでどのように調節するかを調査する.
- ヘテロクロマチン媒介によるDNA修復抑制の克服におけるクロマチンの改造の役割を決定する.
主な方法:
- ヌクレオソーム基板を用いたインビトロ生化学分析.
- yRad51p触媒による関節形成に対するSir2p,Sir3p,Sir4pの影響を調査する.
- SWI/SNF染色体リモデリング酵素が修復中介物質を容易にする役割を評価する.
主要な成果:
- Sir3pが核細胞基質に添加され,Sir2p/Sir4pによって強化され,yRad51p触媒による関節形成を抑制した.
- Sir媒介抑制は,体内静音化に不可欠なヒストンの残留物に依存していた.
- SWI/SNF酵素はSir3pを駆逐し,Rad54p依存性鎖の侵入を促進し,同類再結合の重要なステップである.
結論:
- ヘテロクロマチンは,再結合修復経路に制約を課します.
- SWI/SNFのようなATP依存の染色体改造酵素は,これらの制約を克服し,ヘテロクロマチン内のDNA修復を促進するために不可欠です.
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