Tasting Temperature — A New Thermal Sensor Discovered in Insects
Have you ever wondered why certain biting insects are attracted to some people more than others? These insects have sensors, known as gustatory receptors, which allow them to smell carbon dioxide and to taste sugar and bitter chemicals like caffeine. These receptors have been studied for over a decade but never linked to thermo-sensation until now. A team of Brandeis University scientists has just discovered a new sensor that allows certain insects to sense temperature, just like a tongue is used to sense taste.
But why is it important for insects to have the ability to sense temperature? Because insects, like most animals, can only survive and reproduce if the temperature is just right. Therefore, modern day animals and insects have developed very sensitive temperature sensors, which detect the very narrow margin in which they can survive.
Research led by postdoctoral fellows Lina Ni and Peter Bronk and assisted by Professor of Biology Leslie Griffith and Associate Professor of Biochemistry Douglas Theobald discovered a previously unknown molecular temperature sensor in fruit flies. This receptor, known as Gr28b, is responsible for sensing external temperatures. The sensor belongs to a family of proteins called gustatory receptors. These are used to determine if the fly is outside of the temperature range in which it can survive, and triggers a quick response to move back towards a more moderate temperature.
The research also resolves previously conflicting views of how a fruit fly senses warmth, by showing that the insect has distinct external and internal systems for thermal detection.
This major discovery opens doors to uncovering how insects sense and respond to heat, which will allow scientists to understand insect migration in response to rising global temperatures. According to Griffith, "This research reveals a new way in which animals detect temperature. It’s important because heat detection is critical for the behavior of insects that spread disease, kill crops, and impact the environment."
Similar sensors are likely to be found in disease-spreading insects like mosquitoes and tsetse flies. This may help scientists better understand how insects target warm-blooded prey and spread disease, such as malaria and sleeping sickness that kill hundreds of thousands annually.
Read more at Brandeis University.
Mosquito image via Shutterstock.