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CRISPR-Mediated Reorganization of Chromatin Loop Structure
Published on: September 14, 2018
通过抑制多染色体关节分子的形成,BLM ortholog,Sgs1可以防止异常交叉
Steve D Oh1, Jessica P Lao, Patty Yi-Hwa Hwang
1Section of Microbiology, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
Cell
|July 31, 2007
概括
布鲁姆旋酶 (BLM) 通过破坏异常的关节分子,在半分裂过程中防止有害的DNA交叉. 这种机制确保了有效的DNA修复,同时最大限度地降低了与交叉交叉相关的风险.
科学领域:
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 布鲁姆螺旋酶 (BLM) 在DNA双链断裂修复 (DSBR) 过程中防止异常交叉至关重要.
- 据认为,BLM通过拆解或防止双霍利德结 (dHJ) 的形成而起作用.
研究的目的:
- 调查Saccharomyces cerevisiae BLM ortholog,Sgs1在预防变过程中异常交叉的作用.
- 阐明Sgs1与调节关节分子形成中的Msh5和Mlh3亲交叉因子之间的对抗关系.
主要方法:
- 在Saccharomyces cerevisiae中进行遗传分析.
- 研究Sgs1,Msh5和Mlh3突变体之间的相互作用.
- 介质变化过程中关节分子 (JM) 的形成的特征.
主要成果:
- Sgs1抑制了在半分裂过程中涉及三个和四个相互连接的双重体的关节分子 (JMs) 的形成.
- Sgs1对抗转交因子Msh5和Mlh3,防止dHJ在msh5细胞中的形成.
- 在msh5和mlh3突变体中,Sgs1突变减轻了交叉缺陷,这表明存在敌对关系.
结论:
- Sgs1和procrossover因子在DSB末端表现出差异性活性,促进生产性dHJ形成,同时防止多色染色体JM.
- 与BLM相关的螺旋酶如Sgs1会破坏异常的JM,最大限度地提高DNA修复效率,并最大限度地减少半变异过程中的有害交叉.
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