Temperature Sensitivity of Fruit Fly Gustatory Receptors

Gustatory receptors are a family of transmembrane proteins that have been studied in the context of insect gustatory and olfactory systems. A recent study has found that GR28b, a seven-transmembrane domain protein in the gustatory receptor family in Drosophila melanogaster, may also be involved in temperature sensing. The thermosensitivity of GR28b raises the possibility of using it as a new thermogenetic tool, which could be used to investigate the function of specific neurons and circuits in the brain. To test this idea, we expressed several GR28b isoforms in Xenopus laevis oocytes and measured their relative temperature sensitivities using two-electrode voltage-clamp. Preliminary results show that GR28b exhibits inward sodium current that increases with temperature.