Biological & Soft Matter Seminar: Single-cell epigenetic inheritance dynamics; can we predict phenotypic changes in future generations?
Hanna Salman, University of Pittsburgh
Non-genetic heterogeneity in physical and functional characteristics of cells proliferates within a population due to stochasticity in intracellular biochemical processes and in the distribution of resources during divisions. On the other hand, it is limited in part by the inheritance of cellular components between consecutive generations. In this talk I will present our new study in which, we measure the dynamics of epigenetic inheritance in the simple bacterial model organism E. coli, and reveal how it contributes to regulating the various cellular properties (size, growth rate, etc.) in future generations. This is achieved using a novel microfluidic device that enables us to track how two sister cells become different from each other over time. Our measurements provide the inheritance dynamics of different cellular properties, and the ‘inertia’ of cells to maintain these properties along time, i.e. cellular memory. We find that cellular memory is property specific, and can last up to ∼10 generations, but decreases under stress. Our findings also provide new insights into how E. coli cell-size is regulated to prevent size divergence over time. The results obtained from this study can help uncover mechanisms of non-genetic inheritance and develop quantitative description of cellular phenotypic changes over extended timescales.