2018.10.08 Functional role of transients in biology
题 目：Functional role of transients in biology
报告人：Arvind Murugan, Ph.D.Assistant Professor of Physics, James Franck Institute, The University of Chicago
The function of biological systems is often explained in terms of the system’s steady states and transients between such states rarely play a leading role. Such explanations are valid when the external environment changes very slowly or very fast relative to internal transients. We argue that many biological systems are in the intermediate regime where the environment changes on the same timescale as internal transients. We show how transients are critical to function in three such systems. In circadian biology, we show how simple transient responses to light changes in the cyanobacterium Prochlorococcus marinus can outperform complex free running clocks in sufficiently noisy conditions. In gene regulation and signaling, we show how regulatory networks can act as temporal feature detectors of high specificity by exploiting transients. Such temporal feature detectors allow different time-varying concentration patterns of one signalling molecule to evoke different downstream outcomes as seen in pathways ranging from Msn2 in yeast to NF-kB in mammalian cells. We conclude with evolutionary dynamics in the immune system where transients can be exploited to find generalist solutions that would otherwise be disfavored.
Arvind Murugan obtained a BS in mathematics from the California Institute of Technology. He earned his PhD in high energy physics from Princeton University. He then transitioned to working on problems at the intersection of biology, theoretical computer science and statistical physics at the Institute for Advanced Study and the John A. Paulson School of Engineering and Applied Sciences at Harvard University. He joined the physics faculty at the University of Chicago in the fall of 2015.