Criticality in gene regulatory networks

Ascertain whether naturally occurring gene regulatory networks operate near dynamical criticality (the edge of chaos), characterized by a maximum Lyapunov exponent close to zero, given the current lack of direct experimental evidence.

Background

Reservoir computing theory and prior work in artificial networks suggest optimal performance at the edge of chaos, balancing ordered and chaotic dynamics. The authors quantify the maximum Lyapunov exponent (MLE) and critical memory capacity in the E. coli recurrent core across spectral radius values and find maximal memory near the onset of chaos.

While cortical circuits have evidence of operating near criticality, the authors note that direct evidence for gene regulatory networks doing so is currently lacking, though synthetic implementations of critical behavior in E. coli exist.

This motivates determining whether GRNs in vivo are tuned to criticality, potentially via controllable parameters affecting global gene expression strength.