Genomic anlysis of stenogmay mating behavior in the Culex pipiens complex.

The Culex pipiens complex mosquitoes are major vectors for several arboviruses including West Nile virus in the United States. Within Cx. pipiens complex there are three biotypes that differ mainly in eco-physiological and behavioral characteristics such as habitat selection, blood meal preference, mating behavior and overwintering strategy and yet are difficult to differentiate morphologically. The three biotypes are Cx. pipiens form molestus F., Cx. pipiens f. pipiens L. and Cx. pipiens quinquefasciatus (aka Cx. quinquefasciatus). The low number of genetic markers has been the key obstacle in performing genetic studies in the Cx. pipiens complex. In post genomic era plethora of single nucleotide polymorphisms (SNPs) were discovered from carious genomic data and provide a valuable resource to develop informative molecular markers. In the species complex, the bioytpes’ morphological similarity creates a need for accurate identification methods to differentiate between biotypes. Utilizing the novel SNPs found, here we show high resolution melting curve analysis as a method which distinguish biotypes efficiently at low cost. Reproductive behavior of vector mosquitoes is important to understanding the processes of disease transmission. Hybridization of these biotypes is known to occur, even though form pipiens mate above ground in larges spaces (eurygamy) and form molestus preferentially in small spaces (stenogamy). Hybridization allow gene flow of biotype-specific traits that are crucial in the disease transmission cycle including host preferences, diapause and autogeny. In this study, we have also examined the mating behaviors, insemination rates, fecundity and fertility in parental and F1 hybrids between Culex pipiens form pipiens and Cx. pipiens f. molestus in stenogamy conditions to look at mate competitiveness and specificity for the sterile insect program. In summary, manipulating genes that control either directly or indirectly to the mating behavior of Culex pipiens complex mosquitoes is crucial for the sterile insect technique (SIT). In this context, a functional genomics study can elucidate the potential genes to be utilized for a genetically driven SIT program. Here we have performed RNA-seq to quantify genetic variations by linking SNPs and transcripts of two Culex pipiens biotypes that exhibit stenogamy and eurygamy mating behavior.