MaAts, an alkylsulfatase, contributes to fungal tolerances against UV-B irradiation and Heat-shock in Metarhizium acridum

Sulfatases are usually divided into three classes, the type I, type II and type III sulfatases. The type III sulfatase, alkylsulfatase, could hydrolyze the primary alkyl sulfates, such as sodium octyl sulfate and sodium dodecyl sulfate. Thus, it has a potential application of SDS biodegradation. However, the roles of alkylsulfatase in biological control fungus still unclear. In this study, an alkylsulfatase gene MaAts was identified from Metarhizium acridum. The deletion strain (disruption of MaAts) and the complemented strain (CP) were constructed to reveal its functions in M. acridum. The activity of alkylsulfatase in deletion MaAts was significantly reduced compared to that in the wild-type strain (WT). Disruption of the MaAts gene delayed conidial germination and conidiation, and significantly declined the fungal tolerances to UV-B irradiation and Heat-shock in M. acridum, while fungal virulence and conidial yield were largely unaffected. RNA-seq was performed to further identify the differetial expression genes (DEGs) influenced by the absence of the MaAts gene in M. acridum. The results showed that 77 DEGs, including 55 upregulated genes and 22 downregulated genes in disruption of MaAts, were screened via the comparative analysis of digital gene expression data from the disruption ofMaAts and WT strains. Of these DEGs, some genes were involved in cell wall synthesis and modification, stress response. These results indicate that MaAts and the DEGs can be exploited to increase the fungal stress tolerances for the improvement of mycopesticides.