Characterization of aquaporins in Culex pipiens quinquefasciatus

Because of its broad geographical range and its feeding preference for a wide range of hosts, Culex pipiens quinquefasciatus poses a significant threat to both human and veterinary health. Female mosquitoes must feed on vertebrate blood in order to obtain the nutrients required to produce mature eggs. When a female mosquito takes a blood meal, she more than doubles her weight, which impairs her flight ability and leaves her susceptible to predators. In order to reduce fluid volume and weight, female mosquitoes rapidly excrete urine during and after taking a blood meal. Aquaporins are water channel proteins that facilitate the movement of water across cell membranes. They have been shown to have a critical function in the excretion of urine by female Aedes aegypti during and after a blood meal. In this study, expression of various aquaporins in different postembryonic developmental stages and tissues of adult female C. pipiens quinquefasciatus was characterized using qPCR. Aquaporins expressed in the malpighian tubules were knocked down using RNAi. Diuresis and desiccation assays were performed to evaluate the knock down effect on the mosquitoes' ability to excrete urine or survive under low humidity conditions.