Uncovering plant epigenetics: new insights into cytosine methylation in rye genomes

In plants, epigenetic modifications play an important role in the regulation of gene expression under different environmental conditions. Methylated cytosine (5mC) is a modification found in many eukaryotes, including plants. However, the synthesis and function of 5mC oxidation derivatives, which play important roles in mammalian systems, is still questionable in plants. Kalinka et al. (2023) examined four species of rye (Secale spp.) to investigate the presence of 5-hydroxymethylcytosine (5hmC) and other 5mC oxidative derivatives. They verified the presence of these derivatives in rye genomes and demonstrated an association with coding regions of DNA, implying a possible role in plant genome regulation.