Molecular Basis of Cytoplasmic Incompatibility Induced by Wolbachia in the Culex Pipiens Mosquito Complex: Role of Transposable Elements?

Symbiosis is a close interaction between different species. The bacteria Wolbachia is the most common endosymbiont (a symbiont living within host cells) described to date. In mosquitoes, Wolbachia induces a form of sterility in crosses between males and females infected with distinct Wolbachia types. This feature makes Wolbachia infection a promising non-chemical tool to reduce human diseases transmitted by mosquitoes. However, the molecular basis of the Wolbachia-induced sterility is still unknown. In the Weill Lab, studies of the evolution of Wolbachia associated with the mosquito Culex pipiens revealed a large variety of Wolbachia types and sterility mechanisms in the mosquito population. Furthermore, the sterility properties of Wolbachia strains evolved quickly in the laboratory strains. We hypothesize that DNA repetitive elements that are found at an unusually high density in the Wolbachia genome may explain the rapid evolution of sterility in this mosquito. Combining the expertise in Wolbachia of Mylène Weill and those in DNA repetitive elements detection and analysis of Anna-Sophie Fiston-Lavier and Dmitri Petrov, we propose here a collaborative research project to study the role of DNA repetitive elements in mosquito sterility induced by Wolbachia. Such study will help developing new approaches to control human diseases propagation by mosquitoes.