DNAの二重鎖の断裂は,Eco1 (Ctf7) を通してゲノム全体の姉妹染色体結合を誘発する
Elçin Unal1, Jill M Heidinger-Pauli, Douglas Koshland
1Carnegie Institution, Howard Hughes Medical Institute, Department of Embryology, 3520 San Martin Drive, Baltimore, MD 21218, USA.
Science (New York, N.Y.)
|July 14, 2007
まとめ
姉妹染色体結合は,Eco1 (Ctf7) によるDNA二重鎖断裂 (DSB) に反応して,DNA複製とは無関係に確立される. このプロセスは,全ゲノムにわたる染色体の完全性を保護します.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- コヘシンは姉妹染色体の結束を媒介し,忠実な染色体分離とDNA二重鎖断裂 (DSB) 修復に不可欠である.
- 結束の確立は,伝統的に,複素体とEco1 (Ctf7) と結合したDNA複製の間にのみ発生すると考えられていた.
研究 の 目的:
- DNA複製以外のDSBに対する反応として結束生成のメカニズムを調査する.
- 凝結とDNA損傷反応におけるEco1 (Ctf7) の二重機能を解明する.
主な方法:
- 芽生える酵母をモデル生物として利用した.
- G2/M段階におけるDSBに対する対応として調査されたEco1 (Ctf7) 活動と結束の確立.
- エコ1のアセチルトランスフェラーゼ活性とDNA損傷のチェックポイントの役割を分析した.
主要な成果:
- G2/MにおけるDSBに対する反応として,Eco1 (Ctf7) に依存し,複製に依存しないコヘション生成が実証された.
- Eco1 (Ctf7) の2つの異なる機能が特定されました:DSBとDNA損傷チェックポイントへの反応として,そのアセチルトランスファーゼ活動を通じて,直接的な凝結の確立と凝結の誘発です.
- 壊れた染色体と未壊れた染色体の両方でDSB誘発の凝結が観察されました.
結論:
- 統一性は複製から独立して確立できることを示すことによって,確立されたモデルに挑戦しました.
- ゲノム安定性におけるEco1 (Ctf7) の二重な役割を強調し,DSB修復とDNA損傷チェックポイントを結びつけました.
- エコ1 (Ctf7) を介して作用するDNA損傷チェックポイントは,染色体の完全性のゲノム全体の保護を提供することを提案しました.
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