Xist lncRNAは3次元ゲノムアーキテクチャを利用して,X染色体全体に広がります
Jesse M Engreitz1, Amy Pandya-Jones, Patrick McDonel
1Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA.
Science (New York, N.Y.)
|July 6, 2013
まとめ
XistロングノンコーディングRNA (lncRNA) は,X染色体3D構造を利用して,無活性化時にX染色体を覆う. 結核は染色体構成を変更し,活性領域にアクセスすることで,新しい場所へ広がります.
科学分野:
- エピジェネティクスとゲノミクス
- RNA 生物学 RNA 生物学
- クロマチンの規制
背景:
- 大量のノンコーディングRNA (lncRNAs) はクロマチンの構造と機能の重要な調節因子です.
- XistなどのlncRNAがゲノム標的に局所する正確なメカニズムは,ほとんど不明です.
- X染色体不活性化 (XCI) は,lncRNA媒介の表遺伝子調節を研究するための重要なモデルシステムである.
研究 の 目的:
- X染色体不活性化 (XCI) の開始および維持中のXist lncRNAの局所化メカニズムを調査する.
- XistがX染色体全体で広範なゲノム標的化を達成する方法を解明する.
主な方法:
- XCI中のXist局所化ダイナミクスを調査しました.
- X染色体構成とXストの相互作用を分析し,活発に転写された領域を分析した.
主要な成果:
- XCI開始時に,Xistは当初,特定のDNA配列から独立したX染色体の遠隔部に局所する.
- Xistは,X染色体の3次元 (3D) 構成を用いて,ターゲット領域を特定します.
- Xistのサイレンシングドメインは,アクティブに転写された領域に広がり,完全な染色体コーティングを可能にするために不可欠です.
結論:
- Xistは3D検索メカニズムを通じてX染色体をコーティングします.
- Xistは,染色体構造を積極的に改変して,その拡散を促進し,新しいゲノム部位にアクセスします.
- この研究は,lncRNA媒介の染色体全体の表遺伝的調節のための新しいモデルを提案しています.
関連する概念動画
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02:32X and Y Chromosomes
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The germline cells such as egg and sperm cells carry only half the number of chromosomes, i.e., 22 autosomes and one sex chromosome. All eggs have an X chromosome, while sperm cells can carry an X or...
The germline cells such as egg and sperm cells carry only half the number of chromosomes, i.e., 22 autosomes and one sex chromosome. All eggs have an X chromosome, while sperm cells can carry an X or...