多能性因子Oct4はCtcfと相互作用し,X染色体のペアリングとカウントを制御します
Mary E Donohoe1, Susana S Silva, Stefan F Pinter
1Howard Hughes Medical Institute, USA.
Nature
|June 19, 2009
まとめ
主要な多能性因子であるOct4は,同類染色体のペアリングとカウントを調節することによって,X染色体不活性化 (XCI) を開始します. この発見は,Oct4を明らかにしています.
科学分野:
- エピジェネティクスと遺伝子調節
- 幹細胞生物学 幹細胞生物学
- ゲノミクスと染色体生物学
背景:
- 胚性幹細胞 (ES) の多能性は,転写因子によって制御される.
- X染色体不活性化 (XCI) は,遺伝子用量のために差別化中に1つの女性X染色体を静止させます.
- XCIは,同種の染色体ペアリング,カウント,およびランダムな選択を伴うもので,細胞の分化と密接に関連しています.
研究 の 目的:
- プラリポテンシー因子とX染色体不活性化 (XCI) の相互関係を解明する.
- XCIの調節におけるOct4の役割を特定する.
- Oct4がX染色体のペアリングとカウントにどのように影響するかを理解するために.
主な方法:
- X不活性化センターで,Oct4の規制性非コーディングRNA遺伝子 (TsixとXite) に結合することを調査した.
- Oct4とXCIトランスファクター (CtcfとYy1) のタンパク質相互作用を調べた.
- 女性細胞における同類のX染色体ペアリングとXCIに対するOct4減少の影響を評価した.
主要な成果:
- Oct4は,XCIの重要な規制者であるTixとXiteと直接結びついています.
- Oct4はCtcfとYy1との複合体を形成し,XCIにとって不可欠である.
- Oct4の枯渇は同類のX染色体ペアリングを廃止し,バイアレルX染色体不活性化につながる.
結論:
- Oct4は,XCI階層のトップにあるマスターレギュレータとして識別されています.
- Oct4は同類のX染色体のペアリングとカウントを誘発し,適切なXCIに不可欠です.
- この研究は,X染色体再プログラムと表遺伝的調節におけるOct4に新しい機能を割り当てています.
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