CTCFの標的的劣化により,染色体領域の局所的な分離がゲノム分割から分離される
Elphège P Nora1, Anton Goloborodko2, Anne-Laure Valton3
1Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158, USA; Roddenberry Center for Stem Cell Biology and Medicine at Gladstone, San Francisco, CA 94158, USA.
Cell
|May 20, 2017
まとめ
転写因子CTCFは哺乳類の染色体折り畳みとトポロジカルアソシエイトドメイン (TAD) の組織化に不可欠である. CTCF について
科学分野:
- ゲノミクス
- 分子生物学
- エピジェネティクス
背景:
- 哺乳類の染色体折り合いのメカニズムは完全に理解されていません.
- 転写因子CTCFは染色体構造の調節に関与する.
研究 の 目的:
- 哺乳類の染色体折りや,トポロジカルアソシエイトドメイン (TAD) の組織におけるCTCFの役割を調査する.
- CTCFがゲノム分割を維持し,トランスクリプションの絶縁体としての機能に不可欠であるかどうかを判断する.
主な方法:
- マウスの胚性幹細胞でオクシン誘導性デグロンシステムを利用した.
- クロマチンの折りたたみ,TAD隔離,ゲノム分割への影響を観察するためにCTCFを枯渇させた.
- クロマチン組織における指示的役割を評価するために,CTCFレベルを回復した.
主要な成果:
- CTCFは,CTCFの標的部位とTADの隔離を投与量に依存した方法でループするために不可欠です.
- CTCFを復元すると 適切な染色体構造が回復し 学習機能が示されます
- CTCFの枯渇は,アクティブと非アクティブのゲノムコンパートメントの分離を妨げません.
- CTCFは,エンハンサーの阻害によって転写分離を媒介するが,ヘテロクロマチンの拡散を防ぐことによって媒介しない.
結論:
- CTCFは哺乳類の染色体折り畳みとTAD組織において重要な役割を果たします.
- ゲノム分割は,CTCFによるTAD隔離とは独立しています.
- CTCFは,ヘテロクロマチンの拡散を阻害するものではなく,増強剤を阻害するトランスクリプションの絶縁剤として機能する.
- これらの発見は哺乳類のゲノム組織に 根本的な洞察を与えてくれます
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