Genome-wide expression profiling of Fusarium graminearum in response to azole fungicide treatment

In this study, a newly developed 8x15K Fusarium graminearum Agilent microarray was applied to analyze transcriptional responses to azole fungicide treatment. Comparative statistical analysis of expression profiles from treated versus untreated fungal liquid cultures uncovered 1058 genes that were significantly differentially expressed. Among the 596 genes with significantly increased transcript levels, analyses using GeneOntology and FunCat annotations detected the ergosterol-biosynthesis pathway genes as the most significantly responding category, providing statistical confirmation of the mode-of-action of azole fungicides. Transcriptional profiling of 54 genes, which encode ABC transporters in F. graminearum, suggested that several of these might be involved in reducing intracellular fungicide concentration. In addition, several genes encoding transcription factors with similarity to yeast genes known to co-ordinate fungicide responses exhibited significant differential expression. Hybridization was performed with cRNA samples either derived from three independent untreated or three independent azole-treated liquid cultures (12 h at 5 mg/l tebuconazole).