Wolbachia infection alters olfactory cued locomotion in Drosophila

The School of Life Sciences, Hubei University, Wuhan 430062, P.R. China; The School of Integrative Biology, University of Queensland, Brisbane, Qld 4072, Australia

^* To whom correspondence should be addressed. Email: e.mcgraw{at}uq.edu.au.

	Abstract

Wolbachia pipientis is an endosymbiotic bacterium present in diverse insect species. Although well studied for its dramatic effects on host reproductive biology, little is known about its effects on other aspects of host biology despite its presence in a wide array of host tissues. This study examined the effects of three Wolbachia strains, on two different Drosophila species, using a laboratory performance assay for insect locomotion in response to olfactory cues. The results demonstrate that Wolbachia infection can have significant effects on host responsiveness that vary with respect to the Wolbachia strain x host species combination. The wRi strain, native to D. simulans, increases basal activity level of the host insect as well as responsiveness to food cues. By contrast, the wMel and the virulent wMelPop strains, native to D. melanogaster, cause slight decreases in responsiveness to food cues but do not alter basal activity levels in the host. Surprisingly, the virulent wMelPop strain has very little impact on host responsiveness in D. simulans. This novel strain x host relationship was artificially created previously by transinfection. These findings have implications for understanding the evolution and spread of Wolbachia infections in wild populations and for Wolbachia based vector-borne disease control strategies currently being developed.