Mosquito heat seeking is driven by an ancestral cooling receptor

Mosquitoes transmit pathogens that kill >700,000 people annually. These insects use body heat to locate and feed on warm-blooded hosts, but the molecular basis of such behavior is unknown. Here, we identify ionotropic receptor IR21a, a receptor conserved throughout insects, as a key mediator of heat seeking in the malaria vector Anopheles gambiae. Although Ir21a mediates heat avoidance in Drosophila, we find it drives heat seeking and heat-stimulated blood feeding in Anopheles. At a cellular level, Ir21a is essential for the detection of cooling, suggesting that during evolution mosquito heat seeking relied on cooling-mediated repulsion. Our data indicate that the evolution of blood feeding in Anopheles involves repurposing an ancestral thermoreceptor from non–blood-feeding Diptera.

Source: ScienceNOW - February 5, 2020 Category: Science Authors: Greppi, C., Laursen, W. J., Budelli, G., Chang, E. C., Daniels, A. M., van Giesen, L., Smidler, A. L., Catteruccia, F., Garrity, P. A. Tags: Neuroscience reports Source Type: news