フォークヘッドの転写因子は,S. cerevisiaeの起源のタイミングと長距離のクラスタリングを確立します
Simon R V Knott1, Jared M Peace, A Zachary Ostrow
1Molecular and Computational Biology Program, University of Southern California, Los Angeles, CA 90089, USA.
Cell
|January 24, 2012
まとめ
イーストフォークヘッド因子Fkh1とFkh2は,初期の起源をクラスタリングすることによって,DNA複製のタイミングをグローバルに制御します. これらの要因は,転写レベルとは無関係に,複製工場に起源を勧誘する.
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
- 細胞生物学 細胞生物学
背景:
- ユカリオットの染色体複製は,複製の起源の表遺伝的調節によって,時間的にも空間的にも組織されています.
- 複製の起源のタイミングは,クロマチンの環境と核の位置づけと関連しているが,そのメカニズムは不明である.
研究 の 目的:
- 複製の起源のタイミングを調節する酵母フォークヘッド転写因子 (Fkh1およびFkh2) の役割を調査する.
- フォークヘッド因子がDNA複製の時間的・空間的組織に影響を与えるメカニズムを解明する.
主な方法:
- Fkh1およびFkh2が欠けている酵母菌株における複製起源のタイミングの分析.
- 複製開始因子 (例えば,Cdc45) と起源認識複合体 (ORC) との起源の関連性の調査.
- フォークヘッド因子,起源,ORCの間の物理的な相互作用の検討.
主要な成果:
- Fkh1とFkh2は,複製起源のタイミングのグローバルな決定因子として識別されています.
- フォークヘッド因子による起源のタイミングの調節は,局所的な転写レベルとは無関係です.
- Fkh1とFkh2は,初期の複製起源のクラスタリングと,G1段階のCdc45との関連付けに不可欠です.
- Fkh1とFkh2は,Fkh活性化された起源と結合し,ORCと物理的に相互作用し,起源のクラスタリングを促進します.
結論:
- Fkh1とFkh2は,複製工場に起源を勧誘することによって,DNA複製のタイミングを組織する上で重要な役割を果たします.
- これらの発見は,フォークヘッド因子が差異的起源発火と染色体領域組織の表遺伝的調節にどのように貢献するかのメカニズムを提供します.
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