Sinclair D, Mills K, Guarente L
Department of Biology, Massachusetts Institute of Technology, Cambridge 02139, USA.
Annu Rev Microbiol. 1998;52:533-60. doi: 10.1146/annurev.micro.52.1.533.
The budding yeast Saccharomyces cerevisiae divides asymmetrically, giving rise to a mother cell and a smaller daughter cell. Individual mother cells produce a finite number of daughter cells before senescing, undergoing characteristic changes as they age such as a slower cell cycle and sterility. The average life span is fixed for a given strain, implying that yeast aging has a strong genetic component. Genes that determine yeast longevity have highlighted the importance of such processes as cAMP metabolism, epigenetic silencing, and genome stability. The recent finding that yeast aging is caused, in part, by the accumulation of circular rDNA molecules has unified many seemingly disparate observations.
出芽酵母酿酒酵母进行不对称分裂，产生一个母细胞和一个较小的子细胞。单个母细胞在衰老前产生有限数量的子细胞，随着年龄增长会经历特征性变化，如细胞周期变慢和不育。对于给定的菌株，平均寿命是固定的，这意味着酵母衰老具有很强的遗传成分。决定酵母寿命的基因突出了诸如cAMP代谢、表观遗传沉默和基因组稳定性等过程的重要性。最近发现酵母衰老部分是由环状rDNA分子的积累引起的，这统一了许多看似不同的观察结果。
