PT - JOURNAL ARTICLE AU - Román A. Corfas AU - Leslie B. Vosshall TI - TRPA1 tunes mosquito thermotaxis to host temperatures AID - 10.1101/027896 DP - 2015 Jan 01 TA - bioRxiv PG - 027896 4099 - http://biorxiv.org/content/early/2015/09/30/027896.short 4100 - http://biorxiv.org/content/early/2015/09/30/027896.full AB - While most ectotherms thermotax only to regulate their temperature, female mosquitoes are attracted to human body heat during pursuit of a blood meal. Here we elucidate the basic rules of Aedes aegypti thermotaxis and test the function of candidate thermoreceptors in this important behavior. We show that host-seeking mosquitoes are maximally attracted to thermal stimuli approximating host body temperatures, seeking relative warmth while avoiding both relative cooling and stimuli exceeding host body temperature. We found that the cation channel TRPA1, in addition to playing a conserved role in thermoregulation and chemosensation, is required for this specialized host-selective thermotaxis in mosquitoes. During host-seeking, AaegTRPA1-/- mutants failed to avoid stimuli exceeding host temperature, and were unable to discriminate between host-temperature and high-temperature stimuli. TRPA1-dependent tuning of thermotaxis is likely critical for mosquitoes host-seeking in a complex thermal environment in which humans are warmer than ambient air, but cooler than surrounding sun-warmed surfaces.