The reasonable and unreasonable effectiveness of equilibrium statistical mechanics in gene regulation

21 March 2025

Leonor Saiz
Department of Biomedical Engineering
UC Davis

Abstract

Gene regulation exemplifies a duality wherein equilibrium statistical mechanics effectively describes quasi-equilibrium behaviors, yet systems maintain functionality under significant perturbations. Time scale separation facilitates quasi-equilibrium conditions, enabling predictive modeling of regulatory mechanisms. However, the persistence of regulatory function during substantial disturbances, such as DNA replication, challenges equilibrium assumptions. This robustness can emerge from compensatory mechanisms, such as transcription factor coordination and DNA modifications, that mitigate transient non-equilibrium effects. This talk will examine how these strategies complement quasi-equilibrium dynamics, revealing the strengths and limits of equilibrium models in explaining gene regulation resilience.