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Mol Pharmacol

Title:		Pharmacological characterization of the rat A2a adenosine receptor functionally coupled to the yeast pheromone response pathway
Author(s):		Price LA; Strnad J; Pausch MH; Hadcock JR;
Address:		"Cyanamid Agricultural Research Center, Princaton, New Jersey 08543-0400, USA"
Journal Title:		Mol Pharmacol
Year:		1996
Volume:		50
Issue:		4
Page Number:		829 - 837
DOI:
ISSN/ISBN:		0026-895X (Print) 0026-895X (Linking)
Abstract:		"The rat A2a adenosine receptor, a G protein-coupled receptor, was functionally expressed in the yeast Saccharomyces cerevisiae. High affinity binding sites for A2a adenosine agonists were detected in yeast membranes containing the endogenous Grx protein Gpa1. Agonist saturation binding isotherms using [3H]5'-N-ethylcarboxamidoadenosine indicated that the A2a adenosine receptor expressed in yeast cell membranes displays pharmacological properties equivalent to those observed when the receptor is expressed in human embryonic kidney 293 cell membranes. The rank order of potency of various agonists in [3H]5'-N-ethylcarboxamidoadenosine competition binding assays performed with yeast cell membranes was comparable to that seen for the receptor expressed in mammalian cell membranes. Adenosine agonist-dependent growth response of yeast strains expressing the A2a adenosine receptor was elicited via activation of the yeast pheromone-response pathway. Induction of a pheromone-responsive FUS1-HIS3 reporter gene in far1 his3 cells permits cell growth in medium lacking histidine. The sensitivity of the bioassay was increased by deletion of the STE2 gene, which encodes the yeast alpha-mating pheromone receptor. The growth response was dose dependent, and agonists of varying affinities displayed a rank order of potency comparable to that observed in competition binding assays. Agonist-activated growth assays performed in liquid culture gave ED50 values for various adenosine agonists consistent with reported Kd alpha values. Yeast strains expressing a single receptor/G protein complex will be useful as a model system for the study of receptor/G protein interactions in vivo"
Keywords:		"Adenosine/analogs & derivatives/metabolism/pharmacology Adenosine-5'-(N-ethylcarboxamide) Animals Cells, Cultured GTP-Binding Proteins/metabolism/physiology Humans Kidney/physiology Kinetics Phenethylamines/metabolism/pharmacology Pheromones/metabolism/*p;"
Notes:		"MedlinePrice, L A Strnad, J Pausch, M H Hadcock, J R eng 1996/10/01 Mol Pharmacol. 1996 Oct; 50(4):829-37"