通过Eco1 (Ctf7) 引发全基因组姐妹染色体凝聚力的DNA双链断裂
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
概括
通过Eco1 (Ctf7) 通过DNA双链断裂 (DSB) 独立于DNA复制建立姐妹染色体凝聚力. 这一过程保护了全基因组的染色体完整性.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 凝聚素调解姐妹染色体凝聚力,这对于忠实染色体分离和DNA双链断裂 (DSB) 修复至关重要.
- 传统上,人们认为凝聚力建立仅在DNA复制过程中发生,与复制体和Eco1 (Ctf7) 相结合.
研究的目的:
- 研究DNA复制之外的DSB响应凝聚力生成的机制.
- 阐明Eco1 (Ctf7) 在凝聚力和DNA损伤反应中的双重功能.
主要方法:
- 用了开花酵母作为模型生物.
- 调查Eco1 (Ctf7) 活动和凝聚力建立,以响应G2/M阶段的DSB.
- 分析了Eco1的乙转移酶活性和DNA损伤检查点的作用.
主要成果:
- 证明Eco1 (Ctf7) 依赖的,复制独立的凝聚力产生,以响应G2/M的DSB.
- 确定了Eco1 (Ctf7) 的两个不同的功能:直接建立凝聚力和通过其乙转移酶活性触发凝聚力,以应对DSB和DNA损伤检查点.
- 观察到DSB诱导的结合在破碎和不破碎的染色体上.
结论:
- 通过展示凝聚力可以独立于复制而建立,挑战了既定的模型.
- 突出了Eco1 (Ctf7) 在基因组稳定中的双重作用,将DSB修复和DNA损伤检查点联系起来.
- 建议通过Eco1 (Ctf7) 作用的DNA损伤检查点提供全基因组对染色体完整性的保护.
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