Optimal localization patterns in bacterial protein synthesis
Wednesday, the 31th January at 14:00,
room CV003 Uni Carl Vogt
Université Paris 6
Protein synthesis is a process of fundamental importance for life, and involves a complex network of chemical processes and molecular units, such as messenger RNAs (mRNAs) and ribosomes. In the model bacterium Escherichia coli, the strongly condensed DNA nucleoid located at midcell causes strong excluded- volume effects, pushing most mRNAs and ribosomes to the cell poles . Because of this strong spatial inhomogeneity, mRNAs localized to different intracellular locations will be translated at different rates. We will use theoretical models inspired by statistical physics, to quantify the rate of protein synthesis associ- ated with any given mRNA localization pattern. Among the simplest models that can describe phenomena with such a nontrivial spatial structure are the reaction-diffusion equations, which characterize the dependence of concentra- tions of molecular species, such as mRNAs and ribosomes, on space and time. In this presentation, we will seek the mRNA distribution ρ that maximizes the protein synthesis rate given a fixed set of resources, e.g the total mRNA and ribosome number Namely, this results in a constrained, functional optimization problem.