Snf2核群構造によって明らかにされたクロマチンの改造のメカニズム
Xiaoyu Liu1,2,3, Meijing Li1,2,3, Xian Xia1,2
1Ministry of Education Key Laboratory of Protein Science, Tsinghua University, Beijing 100084, China.
Nature
|April 21, 2017
まとめ
SWI/SNF2のようなクロマチンの改造機は ATPを使って DNAの構造を変えます この研究では,酵母SWI/SNF2が核細胞に結合し,DNAを調節するためにどのように結合し,変形するかを明らかにしています.
科学分野:
- 分子生物学
- 構造生物学
- 生物化学
背景:
- 染色体改造剤はATPに依存する酵素で,核細胞の構造を変えることでDNAのアクセシビリティを調節する.
- これらの酵素の仕組みを理解することは 遺伝子調節と細胞過程の解読に不可欠です
研究 の 目的:
- 酵母スイッチ/不発酵サクラソース (SWI2/SNF2) のクロマチンリモデラーの高解像度構造を決定する.
- 核細胞結合とATP駆動の染色体改造の基礎となる分子メカニズムを解明する.
主な方法:
- 構造データを得るために,冷凍電子顕微鏡 (cryo-EM) が使用された.
- 酵素と核細胞の相互作用を研究するために生化学的測定が暗示された.
主要な成果:
- 凍結EM構造は,核細胞結合時にSnf2コアドメインの調整された構成を示し,酵素の活性化を示しています.
- 2つの誘導ブレスヘリクスは,Snf2コアドメインの接触を媒介し,ATP水解と再構成を結びつけるのに不可欠である.
- Snf2は,そのヘリケースモチーフを通じて核細胞DNAのリン酸脊髄を巻き込み,充電された表面を持つ第2のDNA回転にアンカーします.
- 結合部位でのSnf2による局所的DNA変形は,リモデリングのための基板を準備します.
結論:
- この構造は,SWI2/SNF2リモデラーの結合とニュクレオソームの操作に関する前例のないメカニズム的な洞察を提供します.
- 発見は,異なる改造者間で保存された基板の関与メカニズムを強調しています.
- この研究は,ATP依存の染色体改造の構造的基礎を理解するための基礎を築いている.
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