Snf2によるクロマチンの改造の基礎となるDNA転位のメカニズム
Meijing Li1,2,3,4, Xian Xia1,2,4, Yuanyuan Tian1,2,3,4
1MOE Key Laboratory of Protein Science, Tsinghua University, Beijing, China.
Nature
|March 15, 2019
まとめ
構造研究は,Snf2 (サクラロース非発酵性2) 酵素がATPの水解を用いて核細胞をスライドする方法を明らかにしている. 酵素について
科学分野:
- 分子生物学
- 構造生物学
- 生物化学
背景:
- クロマチンの改造剤はDNAのアクセシビリティを修正する酵素です.
- 核細胞のスライディングは多くの染色体リモデラーの重要な機能です.
- Snf2はクロマチンの改造を研究するための原型酵素である.
研究 の 目的:
- Snf2による核細胞転移のメカニズムを解明する.
- 異なるヌクレオチド状態のヌクレオソームに結合するSnf2の構造を決定する.
主な方法:
- X線結晶学
- 生化学的測定法
- 核細胞に結合したSaccharomyces cerevisiae Snf2の構造分析
主要な成果:
- Snf2はADP結合状態で開いた形状を採用し,SHL2でDNAの歪みを誘導する.
- DNAの歪みは DNA鎖の転移を誘導する
- ADP-BeFx結合は閉じた形状を誘導し,核体をリセットする.
結論:
- Snf2の構造の変化は核酸結合状態と相関し,DNA転位を説明する.
- クロマチンの改造におけるATP依存のDNA転位の基本的メカニズムが提案されている.
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