P-582 - Comparative Analysis of Soybean DNA Demethylase Genes to Further Understand Function and Diversification

DNA demethylation is vital for regulating immune response genes during plant pathogen attacks. However, most of our understanding of this process comes from studies in Arabidopsis, while the function of demethylase genes in soybean remains largely unknown. Therefore, this study aims to decipher the functional roles and evolutionary relationship of soybean demethylase genes to understand their role in pathogen infection better. We identified five soybean homologs of Arabidopsis demethylase genes with a conserved DNA glycosylase domain important for DNA demethylation. Our phylogenetic analysis classified demethylase genes into four distinct clades, encompassing Arabidopsis and various plant species. However, soybean genes were found in only two clades, suggesting gene loss or functional divergence. Additionally, a recent gene duplication event in two of the soybean genes was also detected, indicating functional redundancy. Predicted protein models in alphafold3 of DNA demethylase genes in soybean and Arabidopsis contained the same structural two-part DNA glycosylase domain with matching catalytic amino acids, suggesting they have the same enzymatic activity. To further validate our findings, a Ka/Ks analysis and scan of the promoter regions of the genes to examine selection pressure and conserved promoter elements will be done. Soybean DNA demethylase genes share conserved features with Arabidopsis but show potential divergence, suggesting a unique role in pathogen response. These findings provide groundwork for enhancing disease resistance through epigenetic improvement.