Suppr超能文献

控制减数分裂重组修复——明确ZMMs、Sgs1和Mus81/Mms4在交叉形成中的作用。

Controlling meiotic recombinational repair - specifying the roles of ZMMs, Sgs1 and Mus81/Mms4 in crossover formation.

作者信息

Oke Ashwini, Anderson Carol M, Yam Phoebe, Fung Jennifer C

机构信息

Department of Obstetrics, Gynecology and Reproductive Sciences, Center of Reproductive Sciences, University of California, San Francisco, San Francisco, California, United States of America.

出版信息

PLoS Genet. 2014 Oct 16;10(10):e1004690. doi: 10.1371/journal.pgen.1004690. eCollection 2014 Oct.

Abstract

Crossovers (COs) play a critical role in ensuring proper alignment and segregation of homologous chromosomes during meiosis. How the cell balances recombination between CO vs. noncrossover (NCO) outcomes is not completely understood. Further lacking is what constrains the extent of DNA repair such that multiple events do not arise from a single double-strand break (DSB). Here, by interpreting signatures that result from recombination genome-wide, we find that synaptonemal complex proteins promote crossing over in distinct ways. Our results suggest that Zip3 (RNF212) promotes biased cutting of the double Holliday-junction (dHJ) intermediate whereas surprisingly Msh4 does not. Moreover, detailed examination of conversion tracts in sgs1 and mms4-md mutants reveal distinct aberrant recombination events involving multiple chromatid invasions. In sgs1 mutants, these multiple invasions are generally multichromatid involving 3-4 chromatids; in mms4-md mutants the multiple invasions preferentially resolve into one or two chromatids. Our analysis suggests that Mus81/Mms4 (Eme1), rather than just being a minor resolvase for COs is crucial for both COs and NCOs in preventing chromosome entanglements by removing 3'- flaps to promote second-end capture. Together our results force a reevaluation of how key recombination enzymes collaborate to specify the outcome of meiotic DNA repair.

摘要

交叉互换(COs)在减数分裂过程中确保同源染色体正确配对和分离方面起着关键作用。细胞如何平衡CO与非交叉互换(NCO)结果之间的重组尚不完全清楚。更缺乏的是限制DNA修复程度的因素,以使单个双链断裂(DSB)不会引发多个事件。在这里,通过解释全基因组重组产生的特征,我们发现联会复合体蛋白以不同方式促进交叉互换。我们的结果表明,Zip3(RNF212)促进双Holliday连接(dHJ)中间体的偏向切割,而令人惊讶的是,Msh4并非如此。此外,对sgs1和mms4-md突变体中转换片段的详细检查揭示了涉及多个染色单体侵入的不同异常重组事件。在sgs1突变体中,这些多次侵入通常涉及3 - 4条染色单体的多染色单体侵入;在mms4-md突变体中,多次侵入优先解析为一两条染色单体。我们的分析表明,Mus81/Mms4(Eme1)不仅是COs的次要解离酶,对于COs和NCOs通过去除3' - 翼片以促进第二末端捕获来防止染色体缠结也至关重要。我们的结果共同促使人们重新评估关键重组酶如何协作来确定减数分裂DNA修复的结果。

https://cdn.ncbi.nlm.nih.gov/pmc/blobs/2346/4199502/ff8d06d70bf2/pgen.1004690.g001.jpg

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍。

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索

文档翻译

学术文献翻译模型,支持多种主流文档格式。

立即体验