Intra‐ and trans‐generational effects of larval diet on susceptibility to an entomopathogenic fungus, Beauveria bassiana, in the greater wax moth, Galleria mellonella

Abstract

In addition to nutritional conditions experienced by individuals themselves, those experienced by their parents can affect their immune function. Here, we studied the intra-and trans-generational effects of larval diet on susceptibility to an entomopathogenic fungus, Beauveria bassiana, in the greater wax moth, Galleria mellonella. In the first part of the study, a split-brood design was used to compare the susceptibility of full sibs raised either on low-or on high-nutrition larval diet. In the second part of the study, a similar experimental design was employed to investigate the effects of maternal and paternal diet as well as their interaction on offspring's susceptibility. In the first part of the study, we found that individuals fed with high-nutrition diet had higher mortality from infection than individuals fed with lownutrition diet. However, diet did not affect post-infection survival time. Conversely, in the second part of the study, maternal diet was found to have no significant effect on final mortality rate of offspring, but it affected survival time: larvae with high-nutrition maternal diet survived fewer days after infection than larvae with low-nutrition maternal diet. Paternal diet had no significant effect on offspring's susceptibility to the fungus, indicating that paternal effects are not as important as maternal effects in influencing immune function in this species. Our findings provide further indication that maternal nutrition affects immune function in insects, and suggest that the direct effects of nutrition on immunity may be different, yet parallel, to those caused by parental nutrition.

Experimental evolution of immunological specificity

“…The divergent transcriptome signatures for the specific vs. unspecific selection treatments (Fig. 3 and Dataset S6) suggest that the microevolution of specificity relies on changes in metabolism, which is often a deciding factor in the outcome of host-pathogen interactions (48, 49), and immunity. Within the specific selection treatment, the strong transcriptional response upon priming with Btt included gram-positive responsive genes, such as a Toll-3-like receptor and Persephone (14, 45, 46, 50, 51), indicative of Toll pathway activation.…”

Immunity of the greater wax mothGalleria mellonella

“…G. mellonella resistance changes with larval age and depends on many factors such as external temperature, hormones, and diet (Wojda et al, 2004;Wojda & Jakubowicz, 2007;Kangassalo et al, 2015;Krams et al, 2015;Wu et al, 2015a). There is also an increasing number of reports concerning the role of lipid mediators-eicosanoids-in the modulation of G. mellonella immunity (Buyukguzel et al, 2007(Buyukguzel et al, , 2011Stanley et al, 2009).…”

Diet–microbiome–disease: Investigating diet’s influence on infectious disease resistance through alteration of the gut microbiome

“…For example, mice infected with protozoan parasites that cause murine malaria and fed folate-supplemented diets have decreased survival and decreased resistance compared with mice fed the standard dose of recommended folate [28]. Similarly, greater wax moths infected with a fungal parasite and fed high-nutrition diets were more susceptible and experienced a higher mortality rate than infected individuals raised on low-nutrition diet [29].…”