An perspective on the role of methylation-related genes in wheat - interaction.

Unlabelled: Wheat ( L.), a vital cereal crop, provides over 20% of the total calories and protein in the human diet. However, , the pathogen responsible for Fusarium head blight (FHB), poses a significant threat to wheat production by contaminating grains with harmful mycotoxins. Although Fusarium head blight is currently a minor disease in India, it has the potential to cause substantial yield and quality losses, especially if rain occurs during mid-anthesis. Epigenetic mechanisms, including DNA methylation and sRNA accumulation, are crucial in regulating gene expression and enabling plants to adapt to environmental stresses. Previous studies investigating wheat's response to . through transcriptome analysis of lines differing in 2DL FHB resistance QTLs did not fully explore the role of methylation-related genes. To address this gap, we re-analyzed RNA-Seq data to uncover the response of methylation-related genes to pathogen infection. Our analysis revealed that 16 methylation-related genes were down-regulated in the susceptible line 2-2890, with Gene Ontology (GO) analysis linking these genes to L-methionine salvage from methylthioadenosine (GO:0019509), S-adenosylmethionine metabolism (GO:0033353), and steroid biosynthesis (GO:0006694) (-value = 0.001). Co-expression analysis identified a negative correlation (-0.82) between methionine S-methyl-transferase (MSM; TraesCS1A02G013800) and 3-hydroxy-3-methyl-glutaryl coenzyme A reductase (HMGCR; TraesCS5A02G269300). HMGCR also showed negative correlations (-1.00) with genes encoding pathogenesis-related, detoxification proteins, and xylanase inhibitors, with GO associating these genes with methionine S-methyl transferase activity (-value = 0.001). In pathogen-inoculated samples, the elevated expression of HMGCR (Log2 3.25-4.00) and the suppression of MSM (Log2 1.25-3.25) suggest a dual role in stress response and susceptibility, potentially linked to disrupted DNA methylation and isoprenoid biosynthesis pathways. Furthermore, 43 genes down-regulated by miR9678 were associated with biotic stimulus responses and glucan endo-1,4-beta-glucanase activity, highlighting the complex regulatory networks involved in wheat's defense against . . This study reveals the roles of methylation-related genes in susceptible wheat lines 2-2890, providing new insights into their potential impact on pathogen response and plant susceptibility.

Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-024-04179-0.