A new class of ligand-gated ion channel defined by P2x receptor for extracellular ATP.
Extracellular ATP exerts its effects through P2 purinoceptors: these are ligand-gated ion channels (P2x) or G-protein-coupled receptors (P2Y, P2U). ATP at P2x receptors mediates synaptic transmission between neurons and from neurons to smooth muscle, being responsible, for example, for sympathetic vasoconstriction in small arteries and arterioles. We have now cloned a complementary DNA encoding the P2x receptor from rat vas deferens and expressed it in Xenopus oocytes and mammalian cells. ATP activates a cation-selective ion channel with relatively high calcium permeability. Structural predictions suggest that the protein (399 amino acids long) is mostly extracellular and contains only two transmembrane domains plus a pore-forming motif which resembles that of potassium channels. The P2x receptor thus defines a new family of ligand-gated ion channels.
Valera
S
S
Glaxo Institute for Molecular Biology, Geneva, Switzerland.
Hussy
N
N
Evans
R J
RJ
Adami
N
N
North
R A
RA
Surprenant
A
A
Buell
G
G
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D018076:DNA, Complementary; D006801:Humans; D015640:Ion Channel Gating; D007473:Ion Channels / Q000378:metabolism; D008024:Ligands; D008297:Male; D008969:Molecular Sequence Data; D009865:Oocytes; D018408:Patch-Clamp Techniques; D058910:Purinergic P2 Receptor Agonists; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D018048:Receptors, Purinergic P2 / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D014018:Tissue Distribution; D014649:Vas Deferens / Q000378:metabolism; D014981:Xenopus
D018076:DNA, Complementary; D007473:Ion Channels; D008024:Ligands; D058910:Purinergic P2 Receptor Agonists; D012333:RNA, Messenger; D018048:Receptors, Purinergic P2; D000255:Adenosine Triphosphate