美国布兰代斯大学Paul A. Garrity组研究揭示，蚊子寻热是由先天的冷却感受器驱动的。相关论文2020年2月7日发表在《科学》上。

他们确定了离子传递受体IR21a（一种在昆虫中一直保守的受体），是疟疾媒介冈比亚按蚊中寻找热量通路中的关键介质。尽管Ir21a介导了果蝇避热，但他们发现它驱动按蚊中的热量寻找和受热刺激的血液供应。在细胞水平上，Ir21a对于冷却的感知至关重要，这表明在进化过程中寻求蚊子的热量依赖于冷却介导的排斥力。数据表明，按蚊血液喂养的演变涉及重新利用非血液喂养双翅目的先天热感受器。

据了解，蚊子传播的病原体每年杀死超过700,000人。这些昆虫利用体热定位并以温血宿主为食，但是这种行为的分子基础尚不清楚。

附：英文原文

Title: Mosquito heat seeking is driven by an ancestral cooling receptor

Author: Chloe Greppi, Willem J. Laursen, Gonzalo Budelli, Elaine C. Chang, Abigail M. Daniels, Lena van Giesen, Andrea L. Smidler, Flaminia Catteruccia, Paul A. Garrity

Issue&Volume: 2020/02/07

Abstract: 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.

DOI: 10.1126/science.aay9847

Source: https://science.sciencemag.org/content/367/6478/681