划分在半分裂中的联合分子分离路径可以确定一个交叉特定的分离基
Kseniya Zakharyevich1, Shangming Tang, Yunmei Ma
1Department of Microbiology, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
Cell
|April 17, 2012
概括
三种酶在半变化过程中解决霍莱德结,但涉及Sgs1,Exo1和Mlh1-Mlh3的新途径对于酵母和哺乳动物的交叉形成至关重要.
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:
- 同类的重组最终达到霍莱德结点 (HJ) 解析,产生交叉 (CO) 或非交叉产品.
- 在体内控制HJ分辨率的特定酶仍然难以捉摸.
- 在实验室中发现的三个候选HJ解决方法包括Mus81-Mms4,Slx1-Slx4和Yen1.1.
研究的目的:
- 为了研究Mus81-Mms4,Slx1-Slx4和Yen1在介质霍利德结分辨率中的体内作用.
- 为了确定关键的因素和途径,负责交叉形成在半变化过程中.
主要方法:
- 在发芽的酵母半转化过程中对再组合中间体的物理监测.
- 在三种已知的HJ解析 (mms4 slx4 yen1) 中缺少三重突变的分析.
- 在没有已知的解决方案的情况下,研究交叉形成的遗传依赖.
主要成果:
- 所有三个已识别的内核酶 (Mus81-Mms4,Slx1-Slx4,Yen1) 都在体内有助于HJ分辨率.
- 霍莱德交叉分辨率和交叉在缺乏这些分辨率的三重突变体中有效地发生.
- 在这种三重突变中,交叉交叉矛盾地取决于Sgs1螺旋酶,Exo1核酶和Mlh1-Mlh3复合体.
结论:
- 存在一种新的,以前未被描述的介质交叉形成途径,涉及Sgs1,Exo1和Mlh1-Mlh3.
- 这种Sgs1-Exo1-Mlh1-Mlh3通路是开花酵母和可能的哺乳动物中交叉的主要来源.
- 这些发现重新定义了我们对介质变异中交叉控制机制的理解.
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