C. elegans RNAseq during Leucobacter infections
We measured host transcriptional responses in an animal-microbe system that leverages naturally coinfecting bacterial symbionts of Caenorhabditis nematodes and the model host organism Caenorhabditis elegans (N2 line). Coinfection with the defensive symbiont (Leucobacter celer CBX151) compared to infection by the parasite alone (Leucobacter musarum CBX152) attenuates overall virulence. We measured host gene transcription at early and late infection timepoints to profile stage-specific responses across parasite only, defender only, and coinfection treatments. We hypothesized that protected-host responses to infection could be (i) reduced, essentially outsourcing immunity to the defender, (ii) held mostly constant, combining typical endogenous defenses with symbiont protection, (iii) increased or altered to a distinct coinfected-host response to complement microbial protection. As Leucobacter is a globally ubiquitous genus of symbionts with broad host range, our findings not only bear ecological relevance, but advance our fundamental understanding of how hosts interact with defensive microbes.