RAP-1因子は,静かな交配型の場所であるHMLでDNAループの形成に必要である
J F Hofmann1, T Laroche, A H Brand
1Swiss Institute for Experimental Cancer Research (ISREC), Epalinges s/Lausanne.
Cell
|June 2, 1989
まとめ
交配型の遺伝子を横に並べている酵母サイレンサーは,核の支架に結合し,DNAループを形成します. RAP-1タンパク質は,このループ形成に不可欠であり,サイレンスが遺伝子サイレンスを維持するクロマチンのループを定義することを示唆しています.
科学分野:
- 分子生物学は分子生物学である.
- イースト遺伝学 イースト遺伝学
- クロマチンの構造 クロマチンの構造
背景:
- イースト (HML alpha) のサイレント・ペアリング・タイプ・ロクスは,サイレンス・エレメントによって制御されます.
- 遺伝子サイレンシングの構造的基礎を理解することは,発達生物学にとって極めて重要です.
研究 の 目的:
- HMLアルファロカスにおけるクロマチン構造の組織化におけるDNAサイレンサーの役割を調査する.
- サイレンサー領域におけるDNAループ形成の媒介に関与するタンパク質を特定する.
主な方法:
- イーストの核支架タンパク質の分離と特徴付け.
- 核抽出物を用いて,配列特異のDNAループをインビトロで再構成する.
- タンパク質RAP-1のアフィニティ浄化と機能性アッセイ
主要な成果:
- サイレンサーを含むDNA断片は,酵母核の支架に特異的に結合する.
- 配列特異的なDNAループは,サイレンサー-サイレンサーおよびサイレンサー-プロモーターの相互作用を含む,インビトロで再構成されます.
- 核タンパク質RAP-1は,サイレンサーとプロモーター領域に結合し,DNAループの再構成に不可欠です.
結論:
- HMLアルファロカスにおけるサイレンサーは,特定のクロマチンのループ構造を定義する.
- RAP-1は,これらのサイレンサーで定義されたクロマチンのループの形成を媒介する重要なタンパク質です.
- これらのループは,交配型遺伝子の不活性状態を維持することに関与している可能性が高い.
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