独特のクロマチンのシグネチャーは,ヒトの早期発達強化剤を発見する
Alvaro Rada-Iglesias1, Ruchi Bajpai, Tomek Swigut
1Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, California 94305, USA.
Nature
|December 17, 2010
まとめ
研究者らは,ヒト胚性幹細胞 (hESC) で2種類のゲノム制御要素を特定した. 特定の染色体シグネチャーで特徴づけられたこれらの元素は,人間の早期発達を制御し,希少細胞集団の研究の新たな方法を提供します.
科学分野:
- 発達生物学 発達生物学について
- エピジェネティクス エピジェネティクス
- ゲノミクスゲノミクスとは
背景:
- 細胞-フェイト移行は,細胞環境との規制要素からのゲノム情報を統合することに依存しています.
- 人間の胚の発達を制御するゲノム配列を特定することは大きな課題です.
研究 の 目的:
- 人間の胚性幹細胞 (hESCs) のゲノム制御要素の異なるクラスを特定し,特徴づけること.
- 人間の胚の発達と細胞運命を決定するエピジェネティックメカニズムを理解する.
主な方法:
- クロマチンの免疫プレシピテーションに続いてシーケンシング (ChIP-seq) を行い,ユニークなクロマチンのシグネチャーを特定します.
- ヒストンの改変 (H3K4me1,H3K27ac,H3K27me3) とクロマチンの調節体 (p300,BRG1) の分析.
- ゼブラフィッシュの胚における機能的測定法で,強化剤の活性を評価する.
主要な成果:
- hESCでは,特定の染色体マークとレギュレータによって特徴づけられる2つの異なる種類のゲノム要素が特定されました.
- クラス1の元素は,hESC発現遺伝子の活性増強剤である.
- クラス2の"静止系増強剤"は,不活性な発達遺伝子と関連しており,分化時に活性マークを獲得し,細胞タイプとステージに特異的な発現を誘導します.
結論:
- 初期の発達強化剤はhESCで表遺伝子学的に予めマークされ,バランスのとれた強化剤は初期の胚形成において重要な役割を果たします.
- H3K27me3は,初期の発達期における遠隔制御要素において,評価されていない役割を果たしている.
- 特定された調節配列は,初期のヒト胚形成における一時的および希少細胞集団の研究のためのリソースを提供します.
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