Pathogen-induced alterations in methylome during Lr48-mediated APR in wheat (Triticum aestivum L.) 

Abstract Differential DNA methylation due to APR gene Lr48 for leaf rust resistance in wheat cv. CSP44 was examined at pre-adult plant (P-AP) susceptible stage and adult plant (AP) resistant stage. As many as 52,872 differentially methylated regions (DMRs) carrying 897 differentially methylated genes (DMGs) and many intergenic regions were identified. DMGs included exons/introns, promoters and UTRs. Little less than half of DMGs, were also compared with transcriptome data based on RNA-sEq. Susceptibility (at P-AP) was found to be governed by activation (due to hypomethylation) of relatively more genes, whereas resistance (at AP) involved silencing of relatively large number of genes. Using GO terms, DMGs were found to belong to a variety of biological processes including transcription regulation, protein synthesis, signal transduction, defense, photosynthesis, lipid and carbohydrate metabolism. The results of the present study improved our understanding of the epigenetic control of leaf rust APR in wheat.