The Innovative Role of Epigenetic Regulation in Plant Stress Responses

Abstract

In the face of escalating climate change, plants are subjected to an increasing frequency and intensity of abiotic and biotic stresses. While adaptation through natural selection on genetic variation is fundamental, the pace of environmental change often outstrips the rate of genetic adaptation. This review explores the pivotal and innovative role of epigenetic regulation as a crucial mechanism enabling plants to cope with environmental challenges rapidly and flexibly. Epigenetics, comprising heritable changes in gene expression without alterations to the DNA sequence itself, provides a responsive layer of control that integrates environmental signals into the genome's functional output. We delve into the core mechanisms of epigenetic regulation-including DNA methylation, histone modifications, chromatin remodelling, and the action of non-coding RNAs-and detail how they modulate gene expression networks in response to stresses such as drought, salinity, extreme temperatures, and pathogen attack. Furthermore, we examine the compelling evidence for the transgenerational inheritance of stress-induced epigenetic states, positing it as a mechanism for short-term adaptive evolution and ecological memory. The review also discusses the intricate interplay between epigenetic marks and genetic variation, highlighting how epigenetics can influence the rate of phenotypic evolution. Finally, we explore the translational potential of epigenetics in breeding climate-resilient crops and its implications for ecological conservation. By synthesizing recent advances, this article underscores that epigenetic regulation is not merely a companion to genetics but an innovative and central player in plant adaptive responses, offering a new dimension to our understanding of plant evolution and environmental adaptation.