We map a class of well-mixed stochastic models of biochemical feedback in steady state to the mean-field Ising model near the critical point. The mapping provides an effective temperature, magnetic field, order parameter, and heat capacity that can be extracted from biological data without fitting or knowledge of the underlying molecular details. We demonstrate this procedure on fluorescence data from mouse T cells, which reveals distinctions between how the cells respond to different drugs. We also show that the heat capacity allows inference of the absolute molecule number from fluorescence intensity. We explain this result in terms of the underlying fluctuations, and we demonstrate the generality of our work.
Bibliographical noteFunding Information:
This work was supported by Human Frontier Science Program Grant No. LT000123/2014 (A.E.), National Institutes of Health (NIH) Grant No. R01 GM082938 (A.E.), Simons Foundation Grant No. 376198 (T.A.B. and A.M.), and the Intramural Research Program of the NIH, Center for Cancer Research, National Cancer Institute.
© 2019 American Physical Society.