P2RX3 encodes an extracellular ATP-activated non-selective cation channel 1234 that plays a critical role in sensory neurons, mediating gustatory, nociceptive, and visceral reflexes. The receptor functions as a ligand-gated ion channel that responds to both ATP4- and MgATP2- forms of ATP through distinct activation mechanisms 5, with differential physiological outcomes. Structurally, P2RX3 possesses an intracellular domain containing allosteric sites that modulate channel activation and enable coordinated motions with transmembrane domains 6. P2RX3 is a validated therapeutic target for pain syndromes and chr11 cough 7. Spider venom-derived P2X3 antagonists demonstrate potent antinociception in inflammatory and neuropathic pain models without dysgeusia, a common side effect of small-molecule inhibitors 7. The receptor also contributes to endometriosis-associated pelvic pain, with elevated peritoneal expression that is estrogen-regulated 8. P2RX3 expression is dysregulated in multiple pathologies: down-regulated in overactive bladder 9, altered by prenatal alcohol exposure in neural development 10, and abnormally expressed in migraine-patient-derived glutamatergic neurons 11. Regulatory mechanisms include ubiquitin-mediated control via Praja2 12, which modulates P2RX3 expression in Alzheimer's disease contexts.