Olfactory receptors tuned to mustard oils in drosophilid flies
The olfactory system of insects is specialized in detecting a vast array of volatile compounds. Some compounds, like mustard oils (isothiocyanates, ITCs) present in cabbage, broccoli, wasabi, and other Brassicales, are toxic to many insects. However, a lineage of drosophilid flies in the genus Scaptomyza has olfactory receptors tuned to ITCs and has evolved to use these plants as hosts. More recently, researchers in the Whiteman lab have discovered that Drosophila melanogaster, a microbe-feeder, also has olfactory receptors responsive to ITCs, possibly mediating the flies’ olfactory repellence to the compounds. I will use behavioral experiments to continue the investigation on the chemical defense system of drosophilid flies.