Title: Relaxation rate of gene expression kinetics reveals the feedback sign of auto-regulatory gene network
Authors: Chen Jia - University of Texas at Dallas (United States)
Hong Qian - University of Washington (United States)
Min Chen - University of Texas at Dallas (United States) [presenting]
Michael Zhang - University of Texas at Dallas (United States)
Abstract: The transient response to a stimulus and subsequent recovery to a steady state is a fundamental characteristics of a dynamic organism. We study the relaxation kinetics of auto-regulatory gene networks based on the Delbruck-Gillespie process description of single-cell stochastic gene expression. We report a novel relation between the rate of relaxation, characterized by spectral gap of the process, and the sign of feedback loop in the gene regulation. When a network has no feedback, the relaxation rate is precisely the degradation rate of the protein. We show that positive feedback always decreases the relaxation rate while negative feedback always increases it. Numerical simulations demonstrate that this relation provides an effective method for the inference of gross feedback topology of the underlying gene regulatory network by using time-series data of gene expression from either single cells or cell populations.