Epigenetic Ratchet: Spontaneous Adaptation via Stochastic Gene Expression

TL;DR

This paper proposes a stochastic epigenetic mechanism allowing cells to spontaneously adapt by selecting gene expression patterns that enhance growth, without requiring specific gene regulation networks, supported by simulations and theoretical analysis.

Contribution

It introduces a generic, stochastic adaptation mechanism based on epigenetic modifications and marginal stability, applicable to cell biology.

Findings

The mechanism enables spontaneous adaptation without designed gene networks.

Simulations confirm the selection of beneficial gene expression patterns.

The approach is broadly applicable to stochastic biological systems.

Abstract

Adaptation mechanism of cells on the basis of stochastic gene expression and epigenetic modification is proposed. From marginally stable states generated by epigenetic modification, a gene expression pattern that achieves greater cell growth is selected, as confirmed by simulations and analysis of several models. The mechanism does not require any design of gene regulation networks and is shown to be generic in a stochastic system with marginal stability. General relevance of the mechanism to cell biology is also discussed.