Mosquitoes able to smell humans better at night
The data, published in Nature: Scientific Reports, showed that the Anopheles gambiae mosquito in Africa, which is one of the major areas threatened by malaria transmitted by mosquitoes, is able to smell human host odorants better at night.
"This was an exciting opportunity to bring many people and techniques together to make some really fascinating findings on the mosquito's ability to smell humans, its host," Samuel Rund, a doctoral candidate in the laboratory of Duffield and a former Eck Institute for Global Health Fellow, said. "Just think, during the day the mosquito is sleeping and doesn't need to smell you. But when the sun goes down, the mosquito's olfactory system becomes extra-sensitive, and she is ready to smell and then bite you."
The study examined a mosquito's ability to smell over a 24-hour period using proteomic, sensory physiological and behavioral techniques. Examining the role for a major chemosensory family of mosquito proteins, or odorant-binding proteins, in the daily regulation of olfactory sensitivities in the malarial mosquito was the first step. The team found that a daily rhythmic protein abundance of OBPs leaves mosquitoes with a high abundance at night, allowing them to better smell humans.