プロモーター核細胞体の位置とアイデンティティを特定するメカニズム
Paul D Hartley1, Hiten D Madhani
1Department of Biochemistry and Biophysics, University of California, San Francisco, 94158, USA.
Cell
|May 5, 2009
まとめ
RSCの再構築複合体および特定のタンパク質は,遺伝子プロモーターで核細胞フリー領域 (NFR) を確立します. NFR形成は,H2A.Zの堆積に不可欠であり,プロモータークロマチンの組立のための秩序ある経路を明らかにします.
科学分野:
- 分子生物学は分子生物学である.
- エピジェネティクス エピジェネティクス
- クロマチンのダイナミクス
背景:
- ユカリオット遺伝子のプロモーターは,通常,H2A.Zの変異型核細胞に囲まれた核細胞フリー領域 (NFR) を特徴とする.
- DNA-ヒストン熱力学を用いて核細胞の位置を予測することは,限られた成功を収めている.
研究 の 目的:
- 核細胞複合体の再構成が,理論的な予測と核細胞位置の実験的観測の間の不一致を説明する役割を調査する.
- プロモータークロマチンのアーキテクチャアセンブリのオーダーされた経路を解明する.
主な方法:
- S. cerevisiaeにおけるRSCリモデリング複合体の枯渇は,NFRと核子の位置づけへの影響を観察するために.
- RSC,Abf1,Reb1,H2A.Z.の存在または欠如における核細胞体の位置づけの分析
- ステロイド誘導性タンパク質スプライシング戦略を用いて,H2A.Zの堆積を調節する.
主要な成果:
- RSCの枯渇は,NFRの縮小につながり,予測された場所に向かって核細胞体の位置をシフトさせます.
- Mybファミリーのタンパク質Abf1とReb1は,特定のプロモーターの核細胞位置づけに必要であり,結合部位はNFRsで濃縮されています.
- H2A.Zの堆積は核細胞の位置づけに不可欠ではなく,NFRの確立に依存しています.
結論:
- RSCリモデリング複合体は,遺伝子プロモーターのNFRの確立と維持に重要な役割を果たします.
- プロモータークロマチンの組成には,RSC,Abf1,Reb1と,その後のH2A.Zの堆積を含む,オーダーされた経路が存在する.
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