A large family of divergent candidate gustatory receptors has been identified in Drosophila. As with the odorant receptors, one receptor is expressed per sensory neuron, each class of which projects to discrete regions of the brain, allowing a combinatorial coding system for specific recognition of ligands.
Robertson, H. M. (2001, July 24). Taste: Independent origins of chemoreception coding systems? Current Biology. Cell Press. https://doi.org/10.1016/S0960-9822(01)00343-8