Ligand binding to the β -adrenergic receptor involves its rhodopsin-like core

摘要: Recently the genes for several hormone receptors that interact with guanine nucleotide binding proteins (G proteins) have been cloned, including hamster beta 2-adrenergic receptor (beta 2AR), a human AR, turkey erythrocyte AR and porcine muscarinic acetylcholine (MAR). All these share some amino-acid homology rhodopsin, particularly in 7 hydrophobic stretches of residues are believed to represent transmembrane helices. To determine whether differences ligand specificity result from divergence sequences hydrophilic regions receptors, we expressed mammalian cells wild-type proteins, series deletion mutant 2AR. The pharmacology indicates most not directly involved agonists or antagonists receptor. In addition, identified has high agonist affinity but does couple adenylate cyclase.