Functional Analysis Of MaAL Gene In Metarhizium Acridum

Entomopathogenic fungi,as an important insecticidal microorganism,have the advantages of being environmentally friendly,harmless to humans and animals,and sustainable control,but at the same time,they have the disadvantages of slow insecticidal speed,high production cost,unstable control effect,and susceptibility to environmental factors.Important limiting factors for its actual use in the field.Therefore,it has very important theoretical significance and practical application value for the study of genes related to the biocontrol traits of insect pathogenic fungi.Studies have found that Asp f2is a class II allergen of Aspergillus fumigatus and is related to a variety of allergic diseases.Studies in filamentous fungi have found that their homologous proteins play an important role in the process of growth,development,and pathogenicity.At present,the function of its homologous protein has not been reported in insect pathogenic fungi.Therefore,this article aims to clarify the function of Asp f2 homologous protein MaAL（Metarhizium acdrium Asp f2-like）in the model insect pathogenic fungus M.acridum.After its bioinformatics analysis,the MaAL knockout strain（ΔMaAL）and complement（CP）strains were constructed to study the function of MaAL in Metarhizium anisopliae.Get the following results:Not only the conidial germination and the conidial yield increased after knockout MaAL,but also the virulence both topical inoculation and intrahemocoel injection are significantly enhanced,meanwhile the tolerance to UV and heat has increased.Compared with the control strain,the expression of immune genes in Toll pathway and the phenoloxidase（PO）activity in the locusts haemolymph inoculated with the conidia ofΔMaAL mutant was significantly reduced.Perform RNA-seq data analysis on 21 h Appressorium samples,and define 268 differentially expressed genes when the multiple of difference(|log₂^ΔMaAL/WT|)≥2 and FDR≤0.05.According to the annotated gene function analysis,MaAL may be the regulated growth and development,metabolism,immunity and other related genes to regulate virulence.Altogether,this study found that MaAL can regulate the conidial germination and conidial yield of M.acridum through functional studies of MaAL,and the disruption strains are more resistant to UV and heat,and increased pathogenicity.To further clarify the mechanism of MaAL affecting the growth,stress resistance and virulence of M.acridum.