The Signal within the Noise: Efficient Inference of Stochastic Gene Regulation Models using Fluorescence Histograms and Stochastic Simulations

Motivation: In the noisy cellular environment, stochastic fluctuations at the molecular level manifest as cell-cell variability at the population level that is quantifiable using high throughput single-cell measurements. Such variability is rich with information about the cell’s underlying gene regulatory networks, their architecture, and the parameters of the biochemical reactions at their core. Results: We report a novel method, called INSIGHT, for systematically combining high-throughput, time-course flow cytometry measurements with computer-generated stochastic simulations of candidate gene network models to infer the network’s stochastic model and all its parameters. By exploiting the mathematical relationships between experimental and simulated population histograms, INSIGHT achieves scalability, efficiency, and accuracy while entirely avoiding approximate stochastic methods. We demonstrate our method on a synthetic gene network in bacteria and show that a detailed mechanistic model of this network can be estimated with high accuracy and high efficiency. Our method is completely general and can be used to infer models of signalactivated gene networks in any organism based solely on flow cytometry data and stochastic simulations. Availability: A free C source code implementing the INSIGHT algorithm, together with test data, is available from the authors.