ABSTRACT
P2X receptors are a family of trimeric ligand-gated ion channels, activated by the binding of extracellular ATP. Upon activation, they form a nonselective, cation permeable pore, allowing the transit of small metal cations (Na+, K+, Ca2+) and, in some cases, larger organic cations across the cell membrane. Seven subtype variants exist in mammals, named P2X1 – P2X7, with distinct pharmacological and functional characteristics, but a common architecture: each subunit comprises intracellular N- and C-termini, two transmembrane domains, and a protruding ectodomain. Present in a wide range of cell types, they have equally wide-ranging physiological roles, and are implicated in a number of pathologies, making them potential therapeutic targets.
