Andrea Weisse abstract
A mechanistic model of a cell to link cellular trade-offs, gene expression, and growth
Intracellular processes rarely work in isolation but continually interact with the rest of the cell. In microbes, for example, we now know that gene expression across the whole genome typically changes with growth rate. The mechanisms driving such global regulation, however, are not well understood. Here we consider three trade-offs that, because of limitations in levels of cellular energy, free ribosomes, and proteins, are faced by all living cells. We construct a coarse-grained mechanistic model that comprises these trade-offs and describes how the cell imports and digests nutrients from the environment and uses the derived resources for gene expression to drive growth. It thus couples the expression of different types of genes with growth rate and growth rate with a growing population of cells. In this talk, we discuss the essential parts of the model and show how it recovers the typical growth behaviour observed in microbial populations. We then show how the model can be used for applications in systems and synthetic biology. Last, we consider a multi-scale version of the model to simulate competitions between populations of cells in order to study evolutionary benefits of gene regulation.