Global characterization of GH3 family glycoside hydrolase genes in Fusarium verticillioides and functional analysis of FvGH3-6

To clarify the roles of glycoside hydrolase 3 (GH3) family genes in the growth, development, and pathogenicity of <i>Fusarium verticillioides</i>, GH3 family genes were identified in the genome by bioinformatics software, and their expression levels in the infection process of <i>F. verticillioides</i> were analyzed using transcriptome data. The <i>FvGH3-6</i> gene was knocked out and complemented via genetic transformation to explore the role of <i>F. verticillioides</i>. The results demonstrated that a total of 19 GH3 family genes were identified in the genome of <i>F. verticillioides</i>, which were located on 11 chromosomes, encoding amino acids ranging from 559 to 1,034, with relative molecular weights between 61.20 and 113.97 kDa, and containing 1-6 exons. Transcriptome data indicated that during the infection of maize kernels by <i>F. verticillioides</i>, the expression of nine genes, including <i>FvGH3-6</i>, was upregulated at different stages. Knockout of the <i>FvGH3-6</i> gene did not impact the mycelial growth rate of <i>F. verticillioides</i> but reduced the sporulation ability. Compared with the wild type, the pathogenicity of <i>FvGH3-6</i> knockout mutants towards maize grains and stems was weakened. The above results suggest that the glycoside hydrolase gene family participates in the pathogenicity of <i>F. verticillioides</i>, and the <i>FvGH3-6</i> gene plays a significant role in the conidia production and pathogenicity of <i>F. verticillioides</i>.