GDP-mannose transporters (GMTs) have been implicated in the virulence of some important pathogenic fungi, and guanosine diphosphate (GDP) mannose transporters transport GDP-mannose from the cytosol to the Golgi lumen prior to mannosylation, where mannose attaches to the modified protein. GMTs could be potential targets for new antifungal drugs, as disruption of any step in GDP-mannose biosynthesis can affect fungal viability, growth, or virulence. To date, the GDP-mannose transporter has been extensively studied in yeast, but its biological function in fungi, particularly
F. graminearum, is still unclear. In this experimental study, the role of the GDP-mannose transporter in
F. graminearum was investigated by analysing the
VRG4 gene.
FgGmtA and
FgGmtB were blastp-derived from their
Scvrg4 protein sequences and proved to be their functional homologues. The mutant and complementary strains of
FgGmtA,
FgGmtB and
FgGmtA&B genes were generated and used to evaluate the effect of the two GMTs genes on mycelial growth, asexual reproduction, sexual reproduction, cell wall sensitivity, glyphosate synthesis and drug susceptibility. Only in the
FgGmtB and
FgGmtA&B mutants was the rate of mycelial growth slowed, conidium production increased, sexual reproduction impaired, cell wall sensitivity increased, glycemic content decreased, and drug sensitivity reduced. The results of the pathogenicity assessment of GMTs showed that only
FgGmtB affects the patogenicity of
F. graminearum. At the same time, the effect of GMTs on the ability of rhinoceros to synthesise DON toxins was investigated and the results showed that the ability of Δ
FgGmtB and Δ
FgGmtA&B mutants to produce the DON toxin was significantly reduced, and the expression of toxin-related genes was also reduced.
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