Genomic and Functional Analysis of Carbohydrate Esterases in the Maize Pathogen Exserohilum rostratum

Exserohilum rostratum is a causal agent of severe maize leaf spot, posing a threat to maize production. Carbohydrate esterase (CE) can catalyze the removal of acyl modifications from plant cell wall polysaccharides, thereby promoting polysaccharide hydrolysis. A total of 87 CE genes were identified in the E. rostratum ER1 genome. In this study, we conducted a comprehensive analysis of the E. rostratum CE (ErCE) genes, including physicochemical properties, structural features, promoter cis-acting regulatory elements, and functional analysis. Subcellular localization analysis revealed that more than half of ErCEs were located extracellular. ErCEs contain abundant conserved domains, indicating functional diversity of these proteins. The promoter region of ErCE genes contains a rich variety of cis-acting regulatory elements related to plant hormone regulation, stress response, and developmental processes. Functional enrichment analysis indicated that ErCE genes are predominantly involved in metabolic pathways. In addition, the expression pattern revealed significant changes in ErCE genes during E. rostratum infection, indicating that they play an important role in pathogen invasion and lesion expansion. Overall, this study elucidated the structural characteristics and expression patterns of the CE genes in E. rostratum, providing conditions for further exploration of their roles in fungal pathogenesis and laying the foundation for the improvement of sustainable agricultural systems using related genes.