Expression cloning and signal transduction pathway of P2U receptor in mammary tumor cells.
Extracellularly applied ATP, UTP and UDP induce a transient increase in the intracellular Ca2+ concentration of mammary cells via a P2U receptor. The P2U receptor in the mammary tumor cell line MMT060562 was cloned and expressed in the human leukemia cell line K-562. The deduced amino acid sequence of the mammary tumor cell P2U receptor was 98% homologous with that of mouse NG108-15 cells. It was a member of the superfamily of GTP-binding-protein-coupled receptors. ATP and UTP induced the increase in the intracellular concentrations of Ca2+ and inositol-1,4,5-trisphosphate in both mammary tumor cells and P2U-receptor-expressed K562 cells. Dose-response curves on the production of inositol-1,4,5-trisphosphate and Ca2+ by ATP and UTP were consistently similar. Injection of GTP enhanced the ATP-induced outward current and injection of GTP gamma S induced a repetitive outward current. Both pertussis and cholera toxins did not affect ATP-induced calcium increase. It was suggested that the P2U receptor coupled with pertussis- and cholera-toxin-insensitive GTP-binding proteins and activated phosphoinositide turnover.
Enomoto
K
K
Department of Physiology, Shimane Medical University, Izumo, Japan.
Furuya
K
K
Moore
R C
RC
Yamagishi
S
S
Oka
T
T
Maeno
T
T
D000246:Adenosine Diphosphate Ribose / Q000031:analogs & derivatives / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000378:metabolism / Q000494:pharmacology; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002110:Caffeine / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D003001:Cloning, Molecular; D036563:Cyclic ADP-Ribose; D018076:DNA, Complementary / Q000032:analysis; D005260:Female; D005456:Fluorescent Dyes; D016257:Fura-2; D019204:GTP-Binding Proteins / Q000378:metabolism; D006801:Humans; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D007938:Leukemia / Q000378:metabolism; D008325:Mammary Neoplasms, Experimental / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D010716:Phosphatidylinositols / Q000378:metabolism; D018048:Receptors, Purinergic P2 / Q000235:genetics / Q000502:physiology*; D058473:Receptors, Purinergic P2Y2; D012433:Ryanodine / Q000494:pharmacology; D015398:Signal Transduction; D013498:Suramin / Q000494:pharmacology; D014544:Uridine Triphosphate / Q000494:pharmacology
D018076:DNA, Complementary; D005456:Fluorescent Dyes; C546385:P2RY2 protein, human; C546386:P2ry2 protein, mouse; D010716:Phosphatidylinositols; D018048:Receptors, Purinergic P2; D058473:Receptors, Purinergic P2Y2; D036563:Cyclic ADP-Ribose; D012433:Ryanodine; D000246:Adenosine Diphosphate Ribose; D002110:Caffeine; D013498:Suramin; D015544:Inositol 1,4,5-Trisphosphate; D000255:Adenosine Triphosphate; D019204:GTP-Binding Proteins; D002118:Calcium; D016257:Fura-2; D014544:Uridine Triphosphate