Baker's yeast is a valuable model system for the study of biological aging as it can be utilized for the measurement of replicative and chronological life spans in response to interventions. Whereas replicative aging in Saccharomyces cerevisiae mirrors dividing mammalian cells, chronological aging is seen in non-dividing cells. Aging is strongly influenced by the cellular organelles, especially by mitochondria which house essential functions like oxidative phosphorylation. Additionally, peroxisomes were shown to modulate the aging process, mainly by their turnover of reactive oxygen species. There is a fundamental interest in understanding how mitochondria and peroxisomes contribute to cellular aging. This work analyzes chronological aging in yeast mutants that are affected in peroxisomal proliferation and inheritance. Deletion of INP1 (retention of peroxisomes in the mother cell) or PEX11 (division of peroxisomes) leads to clearly reduced life spans compared to the wild-type control under conditions which depend on peroxisomal metabolism. Δinp1 cells are long-lived in contrast to the wild type and Δpex11 when assayed under conditions that not necessitate peroxisome function. Neither treatment affects the index of respiratory capacity, indicating fully functional mitochondria. Evaluation of stress resistances reveals that Δinp1 has significantly higher resistance to the apoptosis elicitor acetic acid. Old Δpex11 cells from an oleate culture are more susceptible to hydrogen peroxide treatment compared to Δinp1 and the wild type. Finally, aged cells are hyper-sensitive to heat shock treatment in contrast to young cells.

中文翻译：

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酿酒酵母突变体的存活和抗逆性的表征受过氧化物酶体遗传和增殖影响，Δinp1和Δpex11。

贝克酵母是用于研究生物衰老的有价值的模型系统，因为它可用于响应干预措施来测量复制和按时间顺序的寿命。酿酒酵母中的复制性衰老反映出正在分裂的哺乳动物细胞，而在未分裂的细胞中发现了按时间顺序的衰老。衰老受到细胞器特别是线粒体的强烈影响，线粒体具有诸如氧化磷酸化等基本功能。另外，过氧化物酶体主要通过活性氧的转换来调节衰老过程。人们对了解线粒体和过氧化物酶体如何促进细胞衰老有着根本的兴趣。这项工作分析了受过氧化物酶体增殖和遗传影响的酵母突变体的时序老化。与野生型对照相比，在依赖过氧化物酶体代谢的条件下，INP1（母细胞中过氧化物酶体的保留）或PEX11（过氧化物酶体的分裂）的缺失导致寿命明显缩短。在不需要过氧化物酶体功能的条件下进行测定时，与野生型和Δpex11相比，Δinp1细胞的寿命长。两种治疗均不影响呼吸能力指数，表明线粒体功能正常。压力抗性的评估表明，Δinp1对凋亡诱导剂乙酸具有明显更高的抗性。与Δinp1和野生型相比，来自油酸盐培养物的旧Δpex11细胞更容易受到过氧化氢处理。最后，与年轻细胞相比，衰老的细胞对热激处理非常敏感。