Molecular neurobiology of Drosophila taste

- Taste neurons are separated into molecularly and functionally distinct populations.
- Taste detection relies on Gr, Ir, Trp, and ppk receptors.
- Taste input can be modulated by context, dietary experience, and starvation.
- Sweet taste input is relayed from the SOG to the AMMC.
- The quality and location of tastants is represented in the mushroom body.

Drosophila is a powerful model in which to study the molecular and cellular basis of taste coding. Flies sense tastants via populations of taste neurons that are activated by compounds of distinct categories. The past few years have borne witness to studies that define the properties of taste neurons, identifying functionally distinct classes of sweet and bitter taste neurons that express unique subsets of gustatory receptor (Gr) genes, as well as water, salt, and pheromone sensing neurons that express members of the pickpocket (ppk) or ionotropic receptor (Ir) families. There has also been significant progress in terms of understanding how tastant information is processed and conveyed to higher brain centers, and modulated by prior dietary experience or starvation.