Duration and dose-dependency of female sexual receptivity responses to seminal fluid proteins in Aedes albopictus and Ae. aegypti mosquitoes

Male mosquitoes transfer seminal fluid proteins (hereafter ‘SFPs’) during mating. These proteins can have profound effects on female behavior in the yellow fever mosquito Aedes aegypti and the Asian tiger mosquito Aedes albopictus. SFPs are thought to be responsible for female refractoriness to mating in both species. However, only limited information is available about the duration of induced refractoriness or the quantity of SFPs required to be effective in Ae. albopictus. Here, we tested the duration of the effect of SFPs on female refractory behavior for both Aedes species. Additionally, we determined the lowest SFP dose required to induce female refractory behavior in Ae. aegypti. Virgin females were injected intra-thoracically with doses ranging from 0.25 to 0.008 equivalents of one male’s SFP amount. Our results demonstrate high sensitivity of female Ae. aegypti and Ae. albopictus to SFPs of their own species, with the majority of females becoming refractory at doses ? 0.031 male-equivalents after injection into the hemocoel. This effect was long-lasting in both species; none of the injected females were inseminated when presented with males of their own species 30 to 34 days post-injection, whereas most saline-injected control females mated at this time point. These results will aid future work to characterize individual SFPs involved in post-mating refractoriness in these two species. Moreover, they show that as is the situation in the mosquito Anopheles gambiae, and unlike Drosophila melanogaster, sperm are not required for the maintenance of a sexual refractoriness response in Ae. aegypti and Ae. albopictus.