Data from: The route of infection determines (Wolbachia) antibacterial protection in (Drosophila)

Bacterial symbionts are widespread among metazoans, and provide a range of beneficial functions. Wolbachia-mediated protection against viral infection has been extensively demonstrated in <i>Drosophila</i>. In mosquitoes that are artificially transfected with <i>D. melanogaster </i>Wolbachia (wMel), protection from both viral and bacterial infections has been demonstrated. However, no evidence for Wolbachia-mediated antibacterial protection has been demonstrated in <i>Drosophila</i> to date. Here we show that the route of infection is key for Wolbachia-mediated antibacterial protection. <i>D. melanogaster </i>carrying Wolbachia showed reduced mortality during enteric – but not systemic - infection with the opportunist pathogen <i>Pseudomonas aeruginosa</i>. Wolbachia-mediated protection was more pronounced in male flies and is associated with increased early expression of the antimicrobial peptide <i>Attacin A</i>, and also increased expression of a ROS detoxification gene (<i>Gst D8</i>). These results highlight that the route of infection is important for symbiont-mediated protection from infection, that Wolbachia can protect hosts by eliciting a combination of resistance and disease tolerance mechanisms, and that these effects are sexually dimorphic. We discuss the importance of using ecologically relevant routes of infection to gain a better understanding of symbiont-mediated protection.