报告题目：Systems Biology of cellular aging - Multigenerational silencing dynamics control cell aging

报  告 人：Prof. Nan HAO (郝楠), University of California San Diego

报告时间：12月20日（周三）上午10:00

报告地点：闵行校区生物药学楼2号楼116会议室

联  系 人：谢志平 zxie@sjtu.edu.cn

报告摘要：

Cellular aging plays an important role in many diseases, such as cancers, metabolic syndromes, and neurodegenerative disorders. There has been steady progress in identifying aging-related factors such as reactive oxygen species and genomic instability, yet an emerging challenge is to reconcile the contributions of these factors with the fact that genetically identical cells can age at significantly different rates. Such complexity requires single-cell analyses designed to unravel the interplay of aging dynamics and cell-to-cell variability. Here we use microfluidic technologies to track the replicative aging of single yeast cells and reveal that the temporal patterns of heterochromatin silencing loss regulate cellular life span. We found that cells show sporadic waves of silencing loss in the heterochromatic ribosomal DNA during the early phases of aging, followed by sustained loss of silencing preceding cell death. Isogenic cells have different lengths of the early intermittent silencing phase that largely determine their final life spans. Combining computational modeling and experimental approaches, we found that the intermittent silencing dynamics is important for longevity and is dependent on the conserved Sir2 deacetylase, whereas either sustained silencing or sustained loss of silencing shortens life span. These findings reveal that the temporal patterns of a key molecular process can directly influence cellular aging, and thus could provide guidance for the design of temporally controlled strategies to extend life span.

报告人简介：

郝楠，博士。2001年于北京大学获学士学位，2006年于北卡罗来纳大学获博士学位，之后在北卡罗来纳大学和哈佛大学/霍华德休斯研究所从事博士后研究，2013年加入加州大学加州大学圣迭戈分校。实验室研究主要关注逆境、衰老和疾病背景下的信号网络结构及动态变化。