This article will explore the diversity of organs that express elements of the taste transduction cascade and their functions in each area. Taken together, the findings suggest that the taste transduction cascade is not restricted to taste per se or even to systems regulating food intake. The receptors mediating taste transduction evolved early in the vertebrate lineage [13], and were adopted widely as a chemodetection system in a variety of organ systems. Questions still remain as to what the natural ligands are for many of the nongustatory functions of the “taste” transduction system [14].
Figure 2. Sites in the body where cells express the canonical taste receptor cascade. Image sourced from NCBI. Available here. "Taste isn't just for taste buds anymore" by Thomas E. Finger and Sue C. Kinnamon.