Damaged DNA repair gene defect leads to decreased life span in Saccharomyces cerevisiae

초록

Damaged DNA accumulation has been referred to be correlated with aging. Environmental DNA damaging agents such as ultraviolet (UV) light and chemical pollutants, and endogeneous factors constantly damage cellular DNA. Such damaged DNA is repaired by various cellular damaged DNA repair systems. Thus, mutations in the DNA repair genes cause damaged DNA accumulation. In our previous study, we showed that mutations in base excision repair (BER) genes drastically increase spontaneous mutagenesis, MMS sensitivity and transcription blockage in yeast. Additional mutations of nucleotide excision repair (NER) genes enhanced these effects. Although accumulation of damaged DNA can lead cells to aging, it is not clearly known of what kinds of DNA damage contribute to aging. To this end, we analyzed the effect of DNA damage repair gene mutation on yeast lifespan. Our results show that mutations of NER and BER genes decreased yeast life span. These results suggest that increased exposure to environmental toxicants reduces life span.