Function Analysis Of Peroxisome FgPex11Gene Family In Fusarium Graminearum

In recent years, wheat scab （Fusarium head blight, FHB） occurs in our country more seriously. Thisis a serious kind of plant diseases, which widespreads in many areas, causes by Fusarium graminearumsensu lato. It leads to many hazards, including huge loss of yield, producing trichothecene mycotoxins,endangering food security and so on. Peroxisome is a type of single-layer membrane organelles, whichparticipates in a variety of physiological metabolism of organisms in eukaryotic cells. The proteins, thatcontrol peroxisome assembly and division, are called peroxins （encoded by Pex genes）. Studies showthe disfunction of peroxisome in human results in serious illness. Therefore, researching the function ofPex gene in Fusarium graminearum can reveal its role in the growth of Fusarium graminearum, such asmycotoxins synthesis mechanism and pathogencity. These understandings are useful in drugdevelpements against FHB and reducing mycotoxin contamination of pathogenic mechanisms.In this study, based on the reverse genetics method, after bioinformatics analysis, we select fivegenes of FgPex11gene family, which may have a significant role in peroxisome metabolic pathway. ByPEG-mediated transformation of protoplasts, we obtain target gene deletion mutant strains andcomplementary strains, and then we research the function of the five genes of FgPex11gene family inFusarium graminearum.1. Acquisition of the FgPex11family’s gene deletion and complementary strains.Through bioinformatics strategy, we analysed and identified five peroxidase genes of FgPex11family in Fusarium graminearum, including FgPex11（FGSG₀0724）, FgPex11-2（FGSG₀6942）,FgPex11b（FGSG₀9251）, FgPex11c（FGSG₀2546） and FgPex11c2. Then we constructed the fivegene’s knockout vector and complementary vector. With these vectors, we successfully obtained themutants of the target genes, detecting by PCR and Southern blot.2. The function of FgPex11and FgPex11c geneFgPex11and FgPex11c gene deletion strains caused the PH-1reduction in aerial hyphae; Forglucose, sorbitol osmotic pressure increased sensitivity; decreased sensitivity to hydrogen peroxide（H2O2）; for wheat reduced virulence; reduced the ability of using fatty acid metabolism, specilly longchain fatty acid; reduced the proliferation of peroxisomes.FgPex11gene deletion strain caused reduced sensitivity to lithium chloride （LiCl）; peritheciaproduction decreased in sexual reproduction; FgPex11c gene deletion caused lithium chloride （LiCl） inincreased sensitivity; unable to produce perithecia completed sexual generation.3. The function of FgPex11-2, FgPex11b and FgPex11c2There showed no significant difference, between the wild-type strain in growth traits, osmoticsensitivity, virulence and other aspects of sexual reproduction, after the deletion of these three genes inPH-1.These’s role needed further experimental analysis.according to our research, FgPex11and FgPex11c had a regulatory role in growth, pathogenicity,sensitivity, etc. in Fusarium graminearum; FgPex11-2’s, FgPex11b’s and FgPex11c2’s function pended further experiments.