A general method for identifying recessive diploid-specific mutations in Saccharomyces cerevisiae, its application to the isolation of mutants blocked at intermediate stages of meiotic prophase and characterization of a new gene SAE2.
A general method for identifying recessive diploid-specific mutations in Saccharomyces cerevisiae, its application to the isolation of mutants blocked at intermediate stages of meiotic prophase and characterization of a new gene SAE2.
复制标题
鉴定酿酒酵母隐性二倍体特异性突变的通用方法，其在减数分裂前期中间阶段阻断的突变体分离中的应用以及新基因 SAE2 的表征。
DOI：
10.1093/genetics/146.3.797
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发表时间：
1997
期刊：
影响因子：
3.3
通讯作者：
Kleckner,N
中科院分区：
文献类型：
--
作者：
McKee,AH;Kleckner,N
我们描述了一种用于鉴定影响酿酒酵母二倍体菌株的隐性突变的通用新方法，以及该方法在鉴定赋予减数分裂前期染色体代谢中间阻断的突变中的应用。该方法使用温度敏感的缀合突变ste7-1与同构现象相结合。感兴趣的突变赋予孢子形成缺陷，该缺陷依赖于启动减数分裂重组和发育减数分裂特异性染色体结构（SPO11）所需的基因。在此筛选中鉴定出DMC1基因的无效突变、RAD50（rad50S）的非无效突变以及命名为SAE1、SAE2和SAE3（SpoEleven缺失时的孢子形成）的三个新基因的突变。还提供了SAE2基因的分子特征以及sae2突变体的减数分裂和有丝分裂表型的特征。由asae2无效突变赋予的表型与之前鉴定的 RAD50 (rad50S) 的非无效突变几乎没有区别。最值得注意的是，这两种突变仅赋予对放射模拟剂甲基磺酸甲酯 (MMS) 的弱敏感性，但完全阻止减数分裂特异性双链断裂的切除和周转。这些观察结果提供了进一步的证据，表明该表型群识别了特定的分子功能。
We describe a general new approach for identifying recessive mutations that affect diploid strains of yeastSaccharomyces cerevisiaeand the application of this method to the identification of mutations that confer an intermediate block in meiotic prophase chromosome metabolism. The method uses a temperature-sensitive conjugation mutationste7-1in combination with homothallism. The mutations of interest confer a defect in spore formation that is dependent upon a gene required for initiation of meiotic recombination and development of meiosis-specific chromosome structure (SPO11). Identified in this screen were null mutations of theDMC1gene, nonnull mutations ofRAD50(rad50S, and mutations in three new genes designatedSAE1, SAE2andSAE3(Sporulation in theAbsence of SpoEleven). Molecular characterization of theSAE2gene and characterization of meiotic and mitotic phenotypes ofsae2mutants are also presented. The phenotypes conferred by asae2null mutation are virtually indistinguishable from those conferred by the previously identified nonnull mutations ofRAD50(rad50S). Most notably, both mutations confer only weak sensitivity to the radiomimetic agent methyl methane sulfonate (MMS) but completely block resection and turnover of meiosis-specific double-strand breaks. These observations provide further evidence that this constellation of phenotypes identifies a specific molecular function.