Research Division of Microbial Sciences, Kyoto University, Kyoto, Japan.
FEMS Yeast Res. 2014 May;14(3):425-34. doi: 10.1111/1567-1364.12136. Epub 2014 Feb 3.
In Saccharomyces cerevisiae, oxidative stress plays an inhibitory role during industrial fermentation. Although previous reports have identified genes required for oxidative stress tolerance, employing the yeast genome-wide screening, these screenings used a homozygous mutant collection which did not include the essential genes whose deletions result in lethality. Here, we report a truly genome-wide screening for the genes required for oxidative stress tolerance, using a heterozygous mutant collection which includes both essential and nonessential genes. Approximately 6300 heterozygous deletion mutants were grown in the presence or absence of H2 O2 . The screening identified a total of 331 genes whose heterozygotes conferred hypersensitivity to H2 O2 , indicating that these genes are required for oxidative stress tolerance. Notably, among these genes, 71 were essential genes. We classified these 71 essential genes based on localization, indicating that the localization of gene products from these essential genes was enriched in the nucleus and nucleolus. Classification of these essential genes based on functional categorizations showed that rRNA synthesis and tRNA synthesis were over-represented, suggesting that nuclear function, such as RNA synthesis, is important in the response to oxidative stress. These results provide a helpful resource for the understanding of the molecular basis of oxidative stress-tolerant mechanisms.
在酿酒酵母中，氧化应激在工业发酵过程中起着抑制作用。尽管之前的研究已经确定了耐氧化应激所需的基因，但这些筛选使用的是纯合突变体集合，其中不包括那些缺失会导致致死的必需基因。在这里，我们使用包含必需基因和非必需基因的杂合突变体集合，报告了一项真正的全基因组筛选，以确定耐氧化应激所需的基因。大约 6300 个杂合缺失突变体在有或没有 H2 O2 的情况下生长。筛选总共鉴定出 331 个基因，其杂合子对 H2 O2 敏感，表明这些基因是耐氧化应激所必需的。值得注意的是，其中 71 个是必需基因。我们根据定位对这 71 个必需基因进行了分类，表明这些必需基因的产物定位于细胞核和核仁中。根据功能分类对这些必需基因进行分类表明，rRNA 合成和 tRNA 合成过度表达，表明核功能，如 RNA 合成，在应对氧化应激中很重要。这些结果为理解氧化应激耐受机制的分子基础提供了有价值的资源。
