Prostaglandin E receptor EP3gamma isoform, with mostly full constitutive Gi activity and agonist-dependent Gs activity.
We recently demonstrated that two exclusively Gi-coupled isoforms of the mouse EP3 receptor, EP3alpha and beta, with different carboxyl-terminal tails, differed in agonist-independent constitutive Gi activity, and the carboxyl-terminal tail-truncated receptor showed full constitutive activity (Hasegawa, H., Negishi, M., and Ichikawa, A. (1996) J. Biol. Chem. 271, 1857-1860). Here we further examined Gi and Gs activities of the third isoform, EP3gamma, coupled to both Gi and Gs. The My receptor showed mostly full constitutive Gi activity and agonist-dependent Gs activity. The truncated receptor also showed agonist-dependent Gs activity, but the level was lower than that of the EP3gamma receptor. Thus, the carboxyl-terminal tail would differentially regulate Gi and Gs activities of the EP3 receptor.
Negishi
M
M
Department of Physiological Chemistry, Faculty of Pharmaceutical Sciences, Kyoto University, Japan.
Hasegawa
H
H
Ichikawa
A
A
D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D000242:Cyclic AMP / Q000378:metabolism; D015232:Dinoprostone / Q000031:analogs & derivatives / Q000494:pharmacology; D019204:GTP-Binding Proteins / Q000378:metabolism*; D018078:Receptors, Prostaglandin E / Q000378:metabolism*; D013329:Structure-Activity Relationship; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D018078:Receptors, Prostaglandin E; D010566:Virulence Factors, Bordetella; C016767:sulprostone; D000242:Cyclic AMP; D019204:GTP-Binding Proteins; D000262:Adenylyl Cyclases; D015232:Dinoprostone