クロマチンの内在的および制御された相分離による組織
Bryan A Gibson1, Lynda K Doolittle1, Maximillian W G Schneider2
1Department of Biophysics and Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
Cell
|September 24, 2019
まとめ
クロマチンはヒストンの尾によって駆動される液体液相分離 (LLPS) を経て,動的滴を形成する. このプロセスはヒストンH1とアセチル化によって影響を受け,ゲノムを異なる核サブドメインに編成するのに役立ちます.
科学分野:
- 分子生物学
- バイオ物理学
- ゲノミクス
背景:
- ユーカリオットクロマチンは,サブドメインに組織された非常に凝縮された,しかしながら動的にアクセス可能な構造です.
- 染色体組織を制御する 物理的原理を理解することは ゲノム調節を解読するのに 極めて重要です
研究 の 目的:
- クロマチン組織における液体液相分離 (LLPS) の役割を調査する.
- ヒストンの改変とタンパク質がクロマチンの相分離とサブドメイン形成にどのように影響するか調べる.
主な方法:
- クロマチンの復元 in vitro
- 細胞核に微小注射したクロマチン
- クロマチンのドロップレットの特性とダイナミクスの特徴
- ヒストンアセチル化とマルチブロモドメインタンパク質 (例えばBRD4) の効果を調査する.
主要な成果:
- 復元されたクロマチンはヒストンの尻尾駆動によるLLPSを受け,密集した動的滴をインビトロおよび核で形成する.
- リンカーヒストーンH1と特定の核細胞間リンカー長さは,クロマチンの相分離を促進し,調節する.
- ヒストンのアセチル化がLLPSを反発させ,マルチブロモドメインタンパク質は,異なる,不混合のクロマチン相を誘導する.
結論:
- クロマチンの固有の相分離特性は,ゲノム組織とサブドメイン形成を理解するための枠組みを提供します.
- LLPSはクロマチンのアクセシビリティと核構造を調節する重要なメカニズムです.
- ヒストンの改変とタンパク質の相互作用により,クロマチンの相行動が動的に制御され,異なる核区画が形成される.
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