Role of Epigenetics in Modulating Phenotypic Plasticity against Abiotic Stresses in Plants

Abstract

Plants being sessile are always exposed to various environmental stresses, and to overcome these stresses, modifications at the epigenetic level can prove vital for their long-term survival. Epigenomics refers to the large-scale study of epigenetic marks on the genome, which include covalent modifications of histone tails (acetylation, methylation, phosphorylation, ubiquitination, and the small RNA machinery). Studies based on epigenetics have evolved over the years especially in understanding the mechanisms at transcriptional and posttranscriptional levels in plants against various environmental stimuli. Epigenomic changes in plants through induced methylation of specific genes that lead to changes in their expression can help to overcome various stress conditions. Recent studies suggested that epigenomics has a significant potential for crop improvement in plants. By the induction and modulation of various cellular processes like DNA methylation, histone modification, and biogenesis of noncoding RNAs, the plant genome can be activated which can help in achieving a quicker response against various plant stresses. Epigenetic modifications in plants allow them to adjust under varied environmental stresses by modulating their phenotypic plasticity and at the same time ensure the quality and yield of crops. The plasticity of the epigenome helps to adapt the plants during pre- and postdevelopmental processes. The variation in DNA methylation in different organisms exhibits variable phenotypic responses. The epigenetic changes also occur sequentially in the genome. Various studies indicated that environmentally stimulated epimutations produce variable responses especially in differentially methylated regions (DMR) that play a major role in the management of stress conditions in plants. Besides, it has been observed that environmental stresses cause specific changes in the epigenome that are closely associated with phenotypic modifications. However, the relationship between epigenetic modifications and phenotypic plasticity is still debatable. In this review, we will be discussing the role of various factors that allow epigenetic changes to modulate phenotypic plasticity against various abiotic stress in plants.

Multi-omics revolution to promote plant breeding efficiency

“…On the other hand, meiosis has the potential to transfer stress-induced DNA methylation states, leading to some types of transgenerational memory ( Dar et al., 2022 ), even though paramutation-like activities might complicate inheritance patterns ( Minow et al., 2022 ). The availability of several important natural or induced epigenetic variations for agriculture, such as rice, maize, and soybean ( Lloyd and Lister, 2022 ), demonstrates how screening epialleles can significantly increase the genetic variation that breeders can exploit to improve agricultural practices.…”

Epigenetic variation: A major player in facilitating plant fitness under changing environmental conditions

“…Plants maximize their phenotypic plasticity either by increasing the natural variation through large population sizes or by modulating the gene expression patterns to produce altered gene functions and novel phenotypes ( Wang et al, 2021 ). Ultimately, it is the availability of sufficient and meaningful plastic response that determines the capacity of plants to fuel reproductive success leading to fitness benefits in changing environments ( Dar et al, 2022 ). Increased reproductive fitness serves as the basis for the survival of natural populations and their colonizing ability in the changing environments, through the amelioration of various kinds of stresses.…”

Molecular insights into mechanisms underlying thermo-tolerance in tomato

“…Acetylation of histones facilitates transcription by loosening condensed chromatin ( Kumar et al., 2021 ). On the other hand, removal of an acetyl moiety from histones by histone deacetylases (HDACs) facilitates chromatin condensation, indicating the significant roles of histone modifications in heat stress ( Füßl et al., 2018 ; Kumar et al., 2021 ; Dar et al., 2022 ). Stress-induced histone modification has been observed in tomato for various kinds of stresses ( Aiese Cigliano et al., 2013 ; González et al., 2013 ; Yu et al., 2018 ; Crespo-Salvador et al., 2020 ; Li et al., 2020 ; Wang et al., 2021 ).…”