The State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No. 27 Shanda South Road, Jinan, 250100, Shandong, People's Republic of China.
Mol Biol Rep. 2012 Apr;39(4):3573-83. doi: 10.1007/s11033-011-1131-5. Epub 2011 Jun 29.
Elevated levels of reactive oxygen species (ROS) can attack almost all cell components including genomic DNA to induce many types of DNA damage. In this study, we used Saccharomyces cerevisiae with various mutations in a biological network supposed to prevent deleterious effects of endogenous ROS to test the effect of such a network on yeast chronological aging. Our results showed that cells with defects in cellular antioxidation, DNA repair and DNA damage checkpoints displayed a mutation rate higher than that of wild-type strain. Moreover, the chronological life span of most mutants as determined by colony formation was found to be shorter than that of wild-type cells, especially for the mutants defective in DNA replication and DNA damage checkpoints, although the observed cell number was almost the same for wild-type and mutant strains. The mutants were finally found to be more sensitive to SDS and lysing enzyme treatment, and that the degree of sensitivity was correlated with their chronological life span.
活性氧（ROS）水平升高会攻击包括基因组 DNA 在内的几乎所有细胞成分，从而诱导多种类型的 DNA 损伤。在这项研究中，我们使用了酿酒酵母中各种突变体，这些突变体存在于一个被认为可以防止内源性 ROS 产生有害影响的生物网络中，以测试该网络对酵母时序老化的影响。我们的结果表明，细胞抗氧化、DNA 修复和 DNA 损伤检查点缺陷的细胞显示出比野生型菌株更高的突变率。此外，通过菌落形成来确定的大多数突变体的时序寿命比野生型细胞短，特别是对于在 DNA 复制和 DNA 损伤检查点有缺陷的突变体，尽管观察到的野生型和突变型菌株的细胞数量几乎相同。最后发现，突变体对 SDS 和溶菌酶处理更敏感，其敏感性程度与它们的时序寿命相关。
