The direct regulation ofAalbdsxonAalVgRis indispensable for ovarian development inAedes albopictus

AbstractBACKGROUNDAedes albopictusis an important vector with an extensive worldwide distribution. Only female mosquitoes play a significant role in the transmission of pathogens.Doublesex(dsx) is a central nexus gene in the insect somatic sex determination hierarchy.RESULTSIn this study, we characterized the full-length sex-specific splicing forms of theAe. albopictus dsxgene (Aalbdsx). Then, we identified 15 direct target genes of DSX in adult females using digital gene expression (DGE) combined with qPCR following a chromatin immunoprecipitation assay (ChIP) with specific DSX antibodies. The knockdown ofAalbdsxsuppressed ovarian development, and the transcript levels of theAalbdsxtargetvitellogenin receptor(VgR) gene decreased, whereasvitellogenin(Vg) expression showed an increase in the fat body. Genes in the majorVgregulatory pathway were also upregulated. Our results suggest that the effects ofAalbdsxRNAi on ovarian development are exerted mainly viaVgRrather thanVg.CONCLUSIONThe results of our study not only provide a reference for the further elucidation of the sex determination cascade and comparative analyses ofdsxtarget interactions in mosquitoes but also reveal potential molecular targets for application to the development of sterile male mosquitoes to be released for vector control.