Abstract
Epigenetic modifications, including DNA methylation and histone modifications, play crucial roles in regulating gene expression and plant development. This study investigates the potential of harnessing natural and induced epigenetic variation for crop improvement, focusing on stress tolerance and yield stability. We analyzed DNA methylation patterns and histone modification marks (H3K4me3, H3K9ac, H3K27me3) in rice (Oryza sativa) and wheat (Triticum aestivum) under drought, salt, and heat stress conditions using bisulfite sequencing and ChIP-seq. Our results reveal that stress-induced epigenetic changes are associated with altered expression of stress-responsive genes, with some modifications stably inherited across generations. In rice, drought stress led to hypermethylation in promoter regions of negative regulators, while salt stress induced hypomethylation in stress-tolerant genotypes. Histone modifications showed dynamic changes, with H3K4me3 enrichment correlating with gene activation and H3K27me3 with repression. We identified epialleles associated with improved stress tolerance and developed epigenetic markers for breeding. Additionally, we demonstrate that targeted epigenetic editing using dCas9-SunTag systems can enhance stress tolerance without genetic modification. Our findings highlight the potential of epigenetic variation as a resource for crop improvement, offering new avenues for sustainable agriculture under climate change.
Keywords
Epigenetic variation, DNA methylation, Histone modifications, Crop improvement, Stress tolerance, Rice, Wheat, Epigenetic editing