By preventing the growth and egg production, is it possible to prevent the spread of mosquito borne viruses?
Expanded abdomen of female Aedes aegypti with disrupted blood digestion.
The mosquito Aedes aegypti transmits blood-borne viral pathogens that cause worldwide scourges such as dengue fever and West Nile virus. The mosquito’s role in disease transmission is closely tied to its blood meals, which support the production of eggs—a process controlled by nutritional and hormonal pathways in the insect’s digestive tract. Bart Bryant et al. (pp. 22391–22398) have uncovered a key regulator of mosquito physiology that controls both blood digestion and egg maturation. Levels of the regulator, a microRNA dubbed miR-275, rise 12 h after the mosquito feeds on blood, suggesting that nutritional and hormonal signals triggered by blood feeding might prompt production of the microRNA. Compared with controls, female mosquitoes in which the authors depleted miR-275 fed normally, but a day after feeding, large volumes of undigested blood accumulated in a region of the mosquitoes’ gut that normally stores nectar, signaling defects in blood digestion and fluid excretion. Further, depleting miR-275 disrupted the normal development of the mosquitoes’ eggs. Because many insect vectors of human diseases harbor miR-275, the authors suggest microRNAs might represent a promising target for measures aimed at reducing disease transmission by disrupting the vectors’ life cycle. — P.N.