Irreversibility in Bacterial Regulatory Networks

TL;DR

This study explores the concept of irreversibility in bacterial gene regulatory networks, revealing how transient gene perturbations can lead to lasting state changes and linking these dynamics to evolutionary responses.

Contribution

It introduces an analysis of irreversibility in extit{E. coli} regulatory networks, highlighting the relationship between network topology and response to perturbations.

Findings

Irreversibility increases near positive circuits in the network.

Predicted irreversibility correlates with evolutionary adaptation.

Transient perturbations can cause lasting state changes in bacterial regulation.

Abstract

Irreversibility, in which a transient perturbation leaves a system in a new state, is an emergent property in systems of interacting entities. This property has well-established implications in statistical physics but remains underexplored in biological networks, especially for bacteria and other prokaryotes whose regulation of gene expression occurs predominantly at the transcriptional level. Focusing on the reconstructed regulatory network of \emph{Escherichia coli}, we examine network responses to transient single-gene perturbations. We predict irreversibility in numerous cases and find that the incidence of irreversibility increases with the proximity of the perturbed gene to positive circuits in the network. Comparison with experimental data suggests a connection between the predicted irreversibility to transient perturbations and the evolutionary response to permanent perturbations.