RNAi of rpS3a suggests a link between this gene and arrested ovarian development during adult diapause in Culex pipiens

Abstract

In mosquitoes that do not enter diapause, rpS3a is consistently expressed, but in mosquitoes programmed for diapause, expression of rpS3a is intermitted during early diapause, but is then consistently elevated in females 1 month and older. RNAi was performed to evaluate a possible function for rpS3a related to the arrested ovarian development during diapause. dsRNA injected into non-diapausing females suppressed ovarian development. Decreased expression of rpS3a following dsRNA injection was confirmed by Northern blot hybridization. Topical application of JHIII, an endocrine trigger for diapause termination in this species, yielded an almost complete recovery from the RNAi effect. We propose that rpS3a is involved in the shut down of ovarian development that characterizes the adult diapause of Cx. pipiens.