Speaker
Description
Plasmids are extrachromosomal DNA molecules widely used in synthetic biology to implement gene circuits and control protein production. At the single-cell level, plasmids replicate stochastically and segregate at division, generating copy-number variability, while at the population level cell growth and division shape plasmid distributions. Existing models typically focus on either intracellular or population dynamics and fail to capture their coupling. We propose an age-structured model linking intracellular plasmid dynamics to population-level distributions. We investigate the long-time behavior of the model in both low-copy and high-copy plasmid regimes. Our analysis reveals how intracellular stochasticity propagates to population-level copy-number distributions and how cell-cycle variability influences plasmid copy-number dynamics and loss. Finally, we calibrate the model against single-cell measurements of plasmid copy numbers and obtain quantitative agreement across distinct plasmid regimes.
