Transcript assembly and quantification by RNA-seq reveals significant differences in gene expression and genetic variants in mosquitoes of the Culex pipiens (Diptera: Culicidae) complex

Authors: Kang, Dave; KIM, SUNGSHIL - Baylor University; COTTEN, MICHAEL - Baylor University; SIM, CHEOLHO - Baylor University

Submitted to: Journal of Medical Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/15/2020
Publication Date: 8/31/2020
Citation: Kang, D.S., Kim, S., Cotten, M.A., Sim, C. 2020. Transcript assembly and quantification by RNA-seq reveals significant differences in gene expression and genetic variants in mosquitoes of the Culex pipiens (Diptera: Culicidae) complex. Journal of Medical Entomology. 58(1):139–145. https://doi.org/10.1093/jme/tjaa167.
DOI: https://doi.org/10.1093/jme/tjaa167

Interpretive Summary: The taxonomy of Culex pipiens complex of mosquitoes is still debated, but in North America it includes three sub-species, Culex pipiens pipiens, Culex pipiens molestus, and Culex quinquefasciatus (or Culex pipiens quinquefasciatus). Although these mosquito sub-species look very similar, they each have unique life history strategies specifically adapted to their ecological niche. Differences include the capability for overwintering diapause, bloodmeal preference, mating behaviors, and reliance on blood meals to produce eggs. These differences are important because they can influence the success of mosquito control programs. Here, we used genetic analysis to identify specific genes that link to sub-species-specific traits between Culex pipiens pipiens and Culex pipiens molestus. The traits include resistance to water loss, reproduction and the ability to detect human hosts. This new information is important to mosquito researchers who will use it to design new mosquito control methods that can be targeted specifically to each sub-species. Such methods will benefit people living in the mosquito territories by reducing mosquito-borne virus infections and have much wider impact as models for design of control programs based on species- and sub-species differences.

Technical Abstract: We utilize transcriptomics to discover significant differences in homologous gene expression and genetic variation between two closely related species of mosquitoes, Culex pipiens pipiens and Culex pipiens molestus. The differences between the two mosquitoes correspond to their divergent life-history traits and include genes related to desiccation resistance, reproduction, autogeny (the ability to reproduce without blood-feeding), olfaction, and inflammatory immune response. This new information will be used by researchers in comparative studies to utilize the genetic differences between the two mosquitoes to develop new methods of control of these vectors of human disease.