Wolbachia is a common heritable bacterial symbiont in insects. Its evolutionary success lies in the diverse phenotypic effects it has on its hosts coupled to its propensity to move between host species over evolutionary timescales. In a survey of natural host–symbiont associations in a range of Drosophila species, we found that 10 of 16 Wolbachia strains protected their hosts against viral infection. By moving Wolbachia strains between host species, we found that the symbiont genome had a much greater influence on the level of antiviral protection than the host genome. The reason for this was that the level of protection depended on the density of the symbiont in host tissues, and Wolbachia rather than the host-controlled density. The finding that virus resistance and symbiont density are largely under the control of symbiont genes in this system has important implications both for the evolution of these traits and for public health programmes using Wolbachia to prevent mosquitoes from transmitting disease.
Survival data in experiment 1 (Original hosts)
Column headers correspond to the Fly species, the Wolbachia strain (W_strain), the Wolbachia infection status (Status), the virus infection treatment (Treatment), the vial number, the total number of flies in a replicate vial (Sum), the number of flies lost during the experiment (Lost) and the number of days post-viral infection. Values in the latter columns indicate the cumulative number of dead flies after virus infection.
Survival_experiment1.txt
Survival data in experiment 2 (Original hosts and STCP line)
Column headers correspond to the batch of infection, the type of host, the Fly species, the Wolbachia strain (W_strain), the Wolbachia infection status (Status), the virus infection treatment (Treatment), the vial number, the total number of flies in a replicate vial (Sum), the number of flies lost during the experiment (Lost) and the number of days post-viral infection. Values in the latter columns indicate the cumulative number of dead flies after virus infection.
Survival_experiment2.txt
FHV titer qPCR data in experiment 1 (Original hosts)
Column headers correspond to the Wolbachia infection status (Status), the Wolbachia strain (W_strain), the Ct values for FHV and the control fly gene Rpl32 (2 technical replicates for each).
FHV_titer_experiment1.txt
FHV titer qPCR data in experiment 2 (Original hosts and STCP line)
Column headers correspond to the type of host, the fly species, the Wolbachia strain (W_strain), the Wolbachia infection status (Status), the Ct values for FHV and the control fly gene Rpl32 (2 technical replicates for each).
FHV_titer_experiment2.txt
Wolbachia density qPCR data in experiment 2 (Original hosts and STCP line)
Column headers correspond to the type of host, the fly species, the Wolbachia strain (W_strain), the Ct values for the Wolbachia gene atpD and the control fly gene Rpl32 (2 technical replicates for each).
Wolbachia_density_experiment2.txt