Variation in Bombyx mori immune response against fungal pathogen Beauveria bassiana with variability in cell wall β‐1,3‐glucan

Strains of a single species of pathogenic fungi that differ in cell wall components can induce differences ofBombyx mori inner immune recognition. AbstractEntomopathogenic fungi are protected by a cell wall with dynamic structure for adapting to various environmental conditions.β-1,3-Glucan recognition proteins activate the innate immune system of insects by recognizing surface molecules of fungi. However, the associations between pathogenicity and the different components of entomopathogenic fungal cell walls remain unclear. ThreeBeauveria bassiana strains were selected that have significantly differing virulence againstBombyx mori. The molecular mechanisms underlying the immune response inB. mori were investigated using RNA sequencing, which revealed differences in the immune response to differentB. bassiana strains at 12  h post-infection. Immunofluorescence assays revealed thatβ-1,3-glucan content had an opposite trend to that of fungal virulence.β-1,3-Glucan injection upregulatedBm βGRP4 expression and significantly reduced the virulence of the high-virulence strain but not that of the medium-virulence or low-virulence strains.Bm βGRP4 silencing inB. mori with RNA interference resulted in the opposite virulence pattern, indicating that the virulence ofB. bassiana was affected by the cell walls ’ content ofβ-1,3-glucan, which could be recognized by BmβGRP4. Furthermore, interference with the geneCnA (calcineurin catalytic A subunit) involved inβ-1,3-glucan synt...
Source: Insect Science - Category: Biology Authors: Tags: ORIGINAL ARTICLE Source Type: research