Data from: Exploring the role of microbiota in mediating sexually dimorphic infection outcomes in mealworm beetles

Sexually dimorphic responses to pathogenic infections in animals may stem
from sex-specific differences in their life history and immune investment.
Recent evidence highlights that such sex-specific variations in immune
responses can also be critically regulated by microbiota. However, direct
experiments to test how microbiota jointly impacts sex-specific immunity
and vulnerability to pathogens are still limited. To this end, we used
Tenebrio molitor beetles to first establish that sexes appear to differ in
their microbiota composition and infection responses. Females were more
vulnerable to bacterial infections and carried a higher bacterial load
than males. When we depleted the microbiota, only females improved their
post-infection survival, leading to a decrease in the level of sex
specific divergence in infection outcomes. Males, on the other hand,
remained unaffected. Microbiota reconstitution (via feeding on faecal
matter) of microbiota-depleted females increased their susceptibility to
infection again, restoring the strong sexual dimorphism. We thus found a
potential association between microbiota and infection responses. We also
found reduced expression of an antimicrobial peptide tenecin 1 in females,
which could be associated with their higher infection susceptibility, but
such immune gene-vs-phenotypic associations were not consistent across
microbiota manipulations. Immune strategies that are required to mediate
the plausible links between microbiota and infection response might thus
vary with microbiota manipulations, warranting future investigations.