The transcription factor FgMed1 is involved in early conidiogenesis and DON biosynthesis in the plant pathogenic fungus Fusarium graminearum

In this study, we functionally characterized the FgMed1, a gene encoding an ortholog of conserved MedA transcription factor known to be a key conidiogenesis regulator in Aspergillus nidulans. The gene deletion mutant FgMed1produced significantly less conidia, and these were generated from abnormal conidiophores devoid of phialides. Additionally, we observed defective sexual development along with reduced virulence and deoxynivalenol (DON) production in Fg Med1. The GFP-tagged FgAcr1 protein localized to the nuclei of conidiophores and phialides during early conidiogenesis. Significantly, RNA-Seq analyses showed that a number of the conidiation- and toxin-related genes are differentially expressed in the FgMed1 mutant in early conidiogenesis. These data strongly suggest that FgMed1 involved in regulation of genes associated with early conidiogenesis, DON production and virulence in F. graminearum.