Identification And Function Research Of Sugar Transport Factor FgFst1 In Fusarium Graminearum

As an important food crop both at home and abroad,wheat has always attracted great attention from all parties.Fusarium graminearum,the causative agent of wheat scab,produces a variety of toxins during the infection of wheat grains,which has a great impact on human health.Studies have found that the deletion of the inositol transporter Fst1 in Fusarium verticillium not only leads to changes in the morphology of the conidia of the mutant strains,but also reduces the mycelial hydrophobicity,and even affects the change in the production of FB1 toxins,but Fst1 in Fusarium graminearum The function of the bacteria is not yet clear.In this study,the BLAST tool on the NCBI website was used to perform a homologous analysis of the gene sequence of Fst1 in Fusarium verticillium,and a gene with high homology to Fst1 in Fusarium graminearum was found by comparison: FgFst1,FGSG＿03168.Bioinformatics analysis found that FgFst1 has 12 α-helical transmembrane structures,which are consistent with the unique structural characteristics of superfamily transporters,and its protein structure is similar to that of sugar transporters.Based on the principle of homologous recombination,the protoplast transformation method was used to knock out FgFst1,and it was found that the mutant strain after losing FgFst1 had significantly reduced conidia production and the number of membranes,and the conidia germination rate decreased significantly.The transcription levels of Tri3 and Tri12 genes involved in the biosynthesis and transport of DON toxin in the mutant strains increased significantly.Compared with the wild-type strain PH-1 and complement strains,the mutant strains have obvious resistance to the fungicide fludioxonil;in the galactose concentration of 0.05 % glycogen and 0.05 % fructose nutrient,ΔFgFst1 colonies Growth is significantly inhibited;in media with fructose concentrations of 1 % and 5 %,the growth inhibition of ΔFgFst1 is lower than that of wild-type strain PH-1;in the absence of sucrose,ΔFgFst1 is less affected by glycogen loss than PH-1.The results show that FgFst1,as a member of the superfamily transporter,may be involved in regulating the biosynthesis of DON toxin and sugar transport in Fusarium graminearum.