Govindan Rangarajan

Govindan Rangarajan

Indian Institute of Science, India

Title: Critical thresholds in cell fate determination


Govindan Rangarajan obtained his Ph.D. from University of Maryland, College Park, USA. He was a Staff Scientist at the Lawrence Berkeley National Laboratory, USA before moving to the Indian Institute of Science, Bangalore. He is currently a Professor there. His research interests include nonlinear dynamics, computational neuroscience and mathematical biology.


It is well known that cell fate depends on a variety of complex interacting factors. Nevertheless it is important to have simple mathematical models that capture the essential features involved in cell fate determination. We hypothesize that there are critical thresholds for expression levels of key genes (such as Myc) involved in the process. Below the critical threshold, the cell has a particular phenotype (say, normal) and above the threshold, the cell has a different phenotype (say, cancer or stem cell). Using tools from nonlinear dynamics we show that the above assumption can lead to reversible changes in cell phenotype. In particular, we implement the threshold in terms of coupling coefficients of nonlinear oscillators in the cell and we demonstrate that these oscillators undergo a bifurcation leading to oscillator death (and consequent change in cell fate) once the threshold is crossed.