Speaker
Description
Many insect species harbour intracellular symbiotic bacteria that are passed on from mothers to offspring. These symbionts employ various strategies that enhance their proliferation, which may impact the host’s fitness in multiple ways. Wolbachia is a common facultative endosymbiont of arthropods but is especially frequent in bees an ecologically important group of pollinators. The reason for its success in this particular group of insects is unclear. We here explore two alternative, not mutually exclusive roles Wolbachia may play in bees. First, we determined if Wolbachia may block viral infections in bees, as has been described for other hosts. We sampled hundreds of bee individuals from three common species for which we characterized the virome, and determined viral and Wolbachia loads. We found no conclusive evidence for Wolbachia influencing viral titres in bees. Second, we used comparative genomics across a wide range of Wolbachia strains to identify potential signatures for nutritional supplementation by the symbiont. This revealed that unlike in most other hosts, Wolbachia in bees is able to synthesize biotin, which may be supplemented to the host. This ability has at least two independent origins in bee Wolbachia which were facilitated by mobile genetic element transfer into the symbiont’s genome. Our data suggests that the ability to produce biotin is a major reason for Wolbachia’s success in many solitary bee species. Furthermore, we observe that biotin provisioning by facultative symbionts may be required for specialised solitary bees that rely on a single plant species as only nutritional source. Overall, our data highlight nutritional supplementation as a potentially common, but so far overlooked mechanism of symbiont spreading in arthropod species.
| Status Group | Other |
|---|---|
| FOR TALKS: Poster Presentation Option | Yes, I’m willing to present as a poster. |