TRP Channels from Sensory Coding to Physiology

Sensory systems allow the detection of external and internal cues essential for adaptive responses. Chemosensation exemplifies this integration, guiding feeding, mating, and toxin avoidance while also influencing physiological regulation. Across taxa, chemical detection relies on diverse receptor families, and emerging evidence reveals that transient receptor potential (TRP) channels-traditionally associated with phototransduction, thermosensation, and mechanotransduction-also mediate chemosensory functions. Studies in Drosophila melanogaster and vertebrates demonstrate that TRPs detect tastants, odorants, and internal chemical states, highlighting their evolutionary conservation and functional versatility. This review synthesizes current insights into the roles of TRP channels across four major domains: taste, smell, internal state, and central circuit modulation. Using D. melanogaster and mammalian systems as comparative frameworks, we highlight how TRP channels function as polymodal sensors, signal amplifiers, and modulators embedded within canonical receptor pathways rather than as standalone chemoreceptors. Recognizing these integrative functions not only expands our understanding of how organisms coordinate behavior with internal states but also points to TRP channels as potential targets for addressing chemosensory disorders and metabolic diseases. This framework highlights key directions for future research into TRP-mediated sensory and homeostatic regulation.