Abstract

With the improvement of single-cell observation techniques it has been found that stochastic processes are vital for many important biological functions. However in many cases it is not known how stochasticity in gene regulatory networks give rise to functional behaviours. We are interested in understanding a new type of stochastic gene regulation: frequency modulated stochastic pulsing which is observed in the expression of bacterial alternative sigma factors. Alternative sigma factors control key biological pathways in bacteria, such as antibiotic resistance. We aim to characterise the regulatory architecture necessary for stochastic pulse regulation, and to explore the evolutionary benefits it confers to the cell. I am taking a quantitative approach by building mathematical models that help us to understand sigma factor pulsing dynamics. From here it is possible to make predictions and generate hypotheses which we can test in the lab. During my talk I will cover some background of stochastic cellular processes, before talking about the biological evidence we have for stochastic pulse regulation in sigma factor expression. I will then introduce the model that I am working on, and talk about its validity and findings, and their implications.