製品結合は,酵母複合体の抑制複合体のゲノム特異性を強制する
Phillip A Dumesic1, Christina M Homer1, James J Moresco2
1Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA.
Cell
|December 24, 2014
まとめ
Cryptococcus neoformansのポリコンブ系は,抑圧的なH3K27meドメインを確立しています. Ccc1を混乱させる
科学分野:
- クロマチンの生物学
- エピジェネティクス エピジェネティクス
- 分子微生物学 分子微生物学
背景:
- ポリコンブ抑制複合体2 (PRC2) は,H3K27メチル化 (H3K27me) と遺伝子静止を確立するために重要である.
- PRC2の機能と基板認識のメカニズムを理解することは,表遺伝的調節を解読する鍵です.
- Cryptococcus neoformansは,保存された表遺伝的経路を研究するためのモデルシステムを提供しています.
研究 の 目的:
- Cryptococcus neoformansのPRC2のような複合体を特徴付けるために.
- H3K27meの堆積と認識におけるクロモドメインタンパク質Ccc1の役割を調査する.
- ヒストン修飾酵素によって異なるクロマチンのドメインがどのように確立されるかを解明する.
主な方法:
- Cryptococcus neoformans.からPRC2のようなタンパク質複合体を浄化する.
- EZH,EED,Ccc1のオーソログを含む主要なサブユニットの遺伝的破壊.
- H3K27meとH3K9meのパターンの分析は,クロマチンの免疫降水および他の分子技術を用いて行われます.
- Ccc1とH3K27meの相互作用を調査する.
主要な成果:
- Cryptococcus neoformansのPRC2のような複合体は,動物のPRC2成分とクロモドメインのタンパク質,Ccc1.1のオーソログを含んでいる.
- Ccc1はH3K27me.me.を直接認識しています.
- Ccc1の破壊は,H3K27meの再分布につながり,H3K9meのヘテロクロマチン領域と一致する.
- H3K9メチルトランスファーゼClr4の損失は,再分配されたH3K27me.me.の損失にもつながります.
結論:
- Ccc1サブユニットによるH3K27meの認識は,抑制ドメインを特定の染色体型に限定するために不可欠です.
- クロマチン修飾複合体をその製品に固定することで,他のクロマチン状態との交錯を防ぐことができます.
- このメカニズムは,製品認識モジュールを持つ酵素が,共通の基板にもかかわらず,異なるクロマチンのドメインを確立する方法を説明します.
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