PKD2L1 (Polycystic Kidney Disease 2-Like 1): PKD2L1 is a transmembrane protein from the polycystic kidney disease family, primarily located in sensory neurons of the peripheral nervous system and certain epithelial cells. It plays a critical role in chemosensation and mechanosensation, particularly in detecting sour taste. Functioning as a non-selective cation channel, PKD2L1 allows ion influx in response to extracellular stimuli, triggering cellular reactions. It is also involved in processes like gastrointestinal sensory signaling and blood pressure regulation.