Innovative functional cAMP assay for studying G protein-coupled receptors: Application to the pharmacological characterization of GPR17

Medicinal Chemistry Unit, School of Pharmacy, University of Camerino, 62032, Camerino, Italy.
Purinergic Signalling (Impact Factor: 3.89). 07/2011; 7(4):463-8. DOI: 10.1007/s11302-011-9245-8
Source: PubMed


In this work, an innovative and non-radioactive functional cAMP assay was validated at the GPR17 receptor. This assay provides a simple and powerful new system to monitor G protein-coupled receptor activity through change in the intracellular cAMP concentration by using a mutant form of Photinus pyralis luciferase into which a cAMP-binding protein moiety has been inserted. Results, expressed as EC(50) or IC(50) values for agonists and antagonists, respectively, showed a strong correlation with those obtained with [(35)S]GTPγS binding assay, thus confirming the validity of this approach in the study of new ligands for GPR17. Moreover, this method allowed confirming that GPR17 is coupled with a G(αi).

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