Infection-specific transcriptional patterns of the maize pathogen Cochliobolus heterostrophus

Southern corn leaf blight (SCLB) caused by Cochliobolus heterostrophus is a destructive disease that threatens global maize (Zea mays) production. Despite a mass of studies were conducted, very little is known about molecular processes employed by the pathogen during infection. There is a need to understand the fungal arms strategy and identify novel functional genes as target for fungicide development. Transcriptome analysis based on RNA sequencing was carried out across conidia germination and host infection of C. heterostrophus. The present study revealed major changes in C. heterostrophus gene expression during host infection. Several differential expressed genes (DEGs) induced in C. heterostrophus infection could be linked toinvolved in biosynthesis of secondary metabolites, peroxisome, energy metabolism, amino acid degradation, and oxidative phosphorylation. In addition, histone acetyltransferase, secreted proteins, peroxisomal proteins, NADPH oxidase, and transcriptional factors were selected for further functional validation. Here, we demonstrated that histone acetyltransferases (Hat2 and Rtt109), secreted proteins (Cel61A and Mep1), peroxisomal proteins (Pex11A and Pex14), NADPH oxidases (NoxA, NoxD, and NoxR), and transcriptional factors (Crz1 and MtfA) play essential roles in C. heterostrophus conidiation, stress adaption, and virulence. Taken together, our study revealed major changes in gene expression associated with C. heterostrophus infection and identified a diverse repertoire of genes critical for successful infection.