A bioactive peptide from the transmembrane 5-intracellular loop 3 region of the human 5HT1a receptor.
15 amino acid peptide from the transmembrane 5-intracellular loop 3 region of the human 5HT1a receptor produced concentration-dependent decreases in agonist binding. This result is consistent with a competitive interaction between peptide, receptor, and G protein at the receptor-G protein interface. Bombesin and a 13 amino acid peptide from the carboxyl terminus region of the receptor were inactive. Additionally, the peptide decreased forskolin-mediated cAMP elevation. Overall, these results suggest that amino acid residues from this region of the receptor are involved in receptor-G protein coupling and that G protein is activated by the receptor.
Hayataka
K
K
Department of Pharmaceutical Sciences, School of Pharmacy, University of Montana, Missoula 59812-1075, USA.
O'Connor
M F
MF
Kinzler
N
N
Weber
J T
JT
Parker
K K
KK
D000818:Animals; D001839:Bombesin / Q000494:pharmacology; D016466:CHO Cells; D006224:Cricetinae; D000242:Cyclic AMP / Q000037:antagonists & inhibitors / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D019204:GTP-Binding Proteins / Q000378:metabolism; D006801:Humans; D010455:Peptides / Q000494:pharmacology; D011817:Rabbits; D011985:Receptors, Serotonin / Q000737:chemistry*; D044263:Receptors, Serotonin, 5-HT1; D017366:Serotonin Receptor Agonists / Q000378:metabolism
D010455:Peptides; D011985:Receptors, Serotonin; D044263:Receptors, Serotonin, 5-HT1; D017366:Serotonin Receptor Agonists; D000242:Cyclic AMP; D019204:GTP-Binding Proteins; D001839:Bombesin