"Delays and Oscillations: Some counterintutive results in biomolecular feedback systems"

This event is sponsored by FAMU-FSU College of Engineering Department of Chemical & Biomedical Engineering.

Abstract: Positive and negative feedback are common network motifs in biomolecular feedback systems, and often networks of positive and negative feedback are synthesized in laboratories to engineer biological processes. Positive feedback is important because it can give rise to multi-stationarity, and negative feedback is important because it is a principal driver of oscillations. In this talk, we will show: (1) that stochasticity in delays can suppress oscillations in negative feedback oscillators and (2) that oscillations are possible in positive feedback systems. Both are counterintuitive results. Negative feedback is observed as generating oscillations in the interior of living cells, which are crowded, heterogeneous, fluctuating environments. The theory we develop shows that oscillations are suppressed in such situations. Positive feedback systems are widely accepted as displaying non-oscillatory dynamics, as they are mainly meant to evoke a large response or none at all, thereby avoiding oscillations. We will discuss potential mechanisms for both of these counterintuitive results.

Bhargav Ram Karamched, Ph.D.

Department of Mathematics and the Institute of Molecular Biophysics

Florida State University

Speaker Bio: Bhargav Karamched is a Biomathematician and theoretical biophysicist. He obtained his Ph. D. from the University of Utah in 2017 in mathematical biology under the supervision of Paul Bressloff, developing models of molecular motor dynamics at the subcellular level. Karamched did his postdoc at the University of Houston and Rice University under Krešimir Josić and Matthew Bennett, developing models of spatial dynamics in synthetic microbial consortia. He began as an Assistant Professor at FSU in 2020 in Biomathematics and Molecular Biophysics. In 2022 Karamched became affiliated with the Program in Neuroscience. His current research focuses on stochastic processes, dynamical systems, non-equilibrium statistical physics, and control theory, with particular applications to biomolecular feedback systems, spatiotemporal ordering in biological systems, and social decision-making. Karamched is specifically interested in developing mathematical models of biological and decision-making processes and analyzing them with mathematical techniques to unveil fundamental principles underlying them.