title: Gut microbiota in Drosophila melanogaster interacts with Wolbachia but does not contribute to Wolbachia-mediated antiviral protection.
abstract: Animals experience near constant infection with microorganisms. A significant proportion of these microbiota reside in the alimentary tract. There is a growing appreciation for the roles gut microbiota play in host biology. The gut microbiota of insects, for example, have been shown to help the host overcome pathogen infection either through direct competition or indirectly by stimulating host immunity. These defenses may also be supplemented by coinfecting maternally inherited microbes such as Wolbachia. The presence of Wolbachia in a host can delay and/or reduce death caused by RNA viruses. Whether the gut microbiota of the host interacts with Wolbachia, or vice versa, the precise role of Wolbachia in antiviral protection is not known. In this study, we used 16S rDNA sequencing to characterise changes in gut microbiota composition in Drosophila melanogaster associated with Wolbachia infection and antibiotic treatment. We subsequently tested whether changes in gut composition via antibiotic treatment altered Wolbachia-mediated antiviral properties. We found that both antibiotics and Wolbachia significantly reduced the biodiversity of the gut microbiota without changing the total microbial load. We also showed that changing the gut microbiota composition with antibiotic treatment enhanced Wolbachia density but did not confer greater antiviral protection against Drosophila C virus to the host. We concluded there are significant interactions between Wolbachia and gut microbiota, but changing gut microbiota composition is not likely to be a means through which Wolbachia conveys antiviral protection to its host.
authors.affiliation: School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia.
authors.forename: Yixin H
authors.initials: YH
authors.lastname: Ye
authors.affiliation: Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, VIC 8006, Australia.
authors.forename: Andrei
authors.initials: A
authors.lastname: Seleznev
authors.affiliation: School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia.
authors.forename: Heather A
authors.initials: HA
authors.lastname: Flores
authors.affiliation: School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia.
authors.forename: Megan
authors.initials: M
authors.lastname: Woolfit
authors.affiliation: School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia. Electronic address: beth.mcgraw@monash.edu.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: McGraw
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D004331:Drosophila melanogaster / Q000382:microbiology*; D000069196:Gastrointestinal Microbiome / Q000187:drug effects; D054884:Host-Pathogen Interactions; D007304:Insect Viruses; D012328:RNA Viruses; D014777:Virus Diseases / Q000382:microbiology*; D020577:Wolbachia
chemical_list: D000900:Anti-Bacterial Agents
keywords: Antiviral protection; Drosophila C virus; Gut microbiota; Wolbachia