Wolbachia confers sex-specific resistance and tolerance to enteric but not systemic bacterial infection in Drosophila

Radhakrishnan B Vasanthakrishnan; Gupta Vanika; Jonathon A Siva-Jothy; Katy M Monteith; Sam P Brown; Pedro F Vale

doi:10.1101/045757

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Wolbachia confers sex-specific resistance and tolerance to enteric but not systemic bacterial infection in Drosophila

Radhakrishnan B Vasanthakrishnan·Gupta Vanika·Jonathon A Siva-Jothy·Katy M Monteith·Sam P Brown·Pedro F Vale

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Abstract

Wolbachia-mediatedprotection against viral infection has been extensively demonstrated in Drosophila and in mosquitoes that are artificially inoculatedwith D. melanogaster Wolbachia (wMel), but to date no evidence for Wolbachia-mediated antibacterial protection has been demonstrated in Drosophila.Here we show that D. melanogaster carrying wMel shows reduced mortality during enteric - but not systemic - infection with the opportunist pathogen Pseudomonas aeruginosa, and that protection is more pronounced in male flies. Wolbachia-mediated protection is associated with increased early expression of the antimicrobial peptide attacinA, followed by increased expression of a ROS detoxification gene (gstD8), and other tissue damage repair genes which together contribute to greater host resistance and disease tolerance. 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.

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Radhakrishnan B Vasanthakrishnan, Gupta Vanika, Jonathon A Siva-Jothy, Katy M Monteith, Sam P Brown, Pedro F Vale. 2016-04-02. Wolbachia confers sex-specific resistance and tolerance to enteric but not systemic bacterial infection in Drosophila. https://doi.org/10.1101/045757

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