The Dynamics of Supply and Demand in mRNA Translation

M. Carmen Romano, Institute for Complex Systems and Mathematical Biology, University of Aberdeen

We study the elongation stage of mRNA translation and show that, in contrast to assumptions of previous models, both the supply and the demand for tRNA resources are important for determining the translation rate of proteins. We extend the paradigmatic totally asymmetric exclusion process (TASEP) to include the fact that the number of available amino acid-tRNAs changes according to the demand in the cell. This corresponds to having hopping rates in the TASEP that are not fixed but depend on the availability of resources. We identify a new limited resources regime, where the current is severely reduced. Importantly, we show that for biologically relevant parameters, mRNA translation is well within this regime.