Wolbachia -mediated antiviral protection is driven by its multimodal effects on Drosophila melanogaster metabolism

Wolbachia , a common endosymbiont of Drosophila melanogaster , provides a profound antiviral effect in insects. Wolbachia -mediated viral interference has been employed to limit the spread of arboviruses, including dengue. However, the mechanisms underpinning Wolbachia -mediated viral interference are not consistently understood. Previous studies have identified resource competition as a potential mechanism by which Wolbachia disrupts viral replication. Our study uses nuclear magnetic resonance (NMR)-based metabolomics to characterize the bi- and tripartite host- Wolbachia -virus interactions using the model insect Drosophila melanogaster , the protective Wolbachia strain w Mel and the pathogenic Drosophila C virus (DCV). The findings reveal that w Mel-infected flies showed increased simple carbohydrate catabolism relative to uninfected Drosophila . DCV infection perturbed nucleotide synthesis and nucleotide abundance in Drosophila compared to uninfected Drosophila , driving metabolism to likely meet the viral replication demands imposed on the host. Notably, co-infected Drosophila exhibited a metabolic profile more similar to w Mel-infected flies than DCV-infected flies, suggesting that w Mel drives metabolism in a direction that at least temporarily inhibits DCV replication. The metabolic profile is indicative of a hypoxic environment that has been known to trigger immune pathways that further contribute to Wolbachia -mediated pathogen blocking. It is probable that Wolbachia -mediated antiviral protection is a multimodal consequence of w Mel's influence on host metabolism, rather than a single mechanism. These findings will guide future research and contribute to the continued success of Wolbachia -based vector control strategies against RNA arboviruses, potentially leading to novel approaches for defending against such pathogens and improving vector control strategies.