Wolbachia and Mosquitoes: Exploring Transmission Modes and Coevolutionary Dynamics in Shandong Province, China

Abstract

Abstract Background Mosquito-borne diseases, including outbreaks of novel mosquito-borne diseases, pose a serious threat to human health. Deployment of the intracellular symbiont Wolbachia has been proposed as a novel strategy to modify mosquitoes with increased resistance to pathogen infection. However, little is known about its interaction with mitochondria during maternal transmission. Method Here, we aimed to determine the genetic structures of 11 Culex pipiens pallens populations and the incidence of Wolbachia infections in Shandong Province, China, to gain a better understanding of the relationship between mosquitoes and Wolbachia. The genetic structure of the Cx. p. pallens population was investigated using the cytochrome oxidase subunit I (COI) gene. Wolbachia infection status assessment, molecular classification, and phylogenetic analysis were performed using molecular markers for the Wolbachia surface protein (WSP) gene. Mosquito–Wolbachia relationship was investigated using tanglegram and distance-based approaches. Results Sequence analysis of the COI gene revealed 26 different mitochondrial DNA haplotypes. The neutrality test and haplotype networks for Cx. p. pallens populations indicated that the species is undergoing demographic expansion in Shandong Province, with significant genetic differentiation between the populations from Qingdao and most other cities. The overall Wolbachia infection rate of Cx. p. pallens was 90.7%; 15 WSP haplotypes were detected. Conclusion Our study revealed the genetic structure of Cx. p. pallens and the prevalence of Wolbachia in Shandong Province, China, offering important scientific information required for developing Wolbachia-based vector control approaches in Shandong Province. These findings would advance current understanding of Wolbachia’s diversity and evolution, aiding in its application as a biocontrol agent.