Identification of Candidate Genes Associated with Trichothecene Biosynthesis in Species Complex Combined with Transcriptomic and Proteomic Analysis.

The species complex is the main causal agent of wheat head blight worldwide. Trichothecenes produced by the pathogen in infected grains have important food safety implications. Previously reported studies on trichothecene production have all focused on the conditions conducive to mycotoxin production, while the molecular mechanisms of trichothecene biosynthesis in strains under normal or non-inducing conditions are still unclear. Here, a global analysis of the fungal gene expression of three strains using the Affymetrix GeneChip under non-inducing conditions is reported. Differentially expressed genes were identified among strains with different trichothecene-production ability, and some novel genes associated with trichothecene biosynthesis were found by bioinformatics analysis. To verify the transcriptome results, proteomic analyses of the three strains were conducted under the same culture conditions. In total, 69 unique fungal proteins were identified in 77 protein spots. Combined with transcriptome and proteome analysis, 27 novel genes were predicted to be associated with trichothecene mycotoxin production. A protein, encoded by , was found to be associated with trichothecene production via proteome analysis. Gene knock-out mutations of resulted in mutants with increased production of trichothecenes. Future functional analysis of the candidate genes identified in this study may reveal new insights into the negative regulation of trichothecene production in the species complex.