RT Journal Article SR Electronic T1 Specificity of Metabotropic Glutamate Receptor 2 Coupling to G Proteins JF Molecular Pharmacology JO Mol Pharmacol FD American Society for Pharmacology and Experimental Therapeutics SP 183 OP 191 DO 10.1124/mol.63.1.183 VO 63 IS 1 A1 Paul J. Kammermeier A1 Margaret I. Davis A1 Stephen R. Ikeda YR 2003 UL http://molpharm.aspetjournals.org/content/63/1/183.abstract AB Metabotropic glutamate receptor 2 (mGluR2) is a class 3 G protein-coupled receptor and an important mediator of synaptic activity in the central nervous system. Previous work demonstrated that mGluR2 couples to pertussis toxin (PTX)-sensitive G proteins. However, the specificity of mGluR2 coupling to individual members of the Gi/o family is not known. Using heterologously expressed mGluR2 in rat sympathetic neurons from the superior cervical ganglion (SCG), the mGluR2/G protein coupling profile was characterized by reconstituting coupling in PTX-treated cells expressing PTX-insensitive mutant Gα proteins and Gβγ. By employing this method, it was demonstrated that mGluR2 coupled strongly with Gαob, Gαi1, Gαi2, and Gαi3, although coupling to Gαoa was less efficient. In addition, mGluR2 did not seem to couple to the most divergent member of the Gi/o family, Gαz, although Gαz coupled strongly to the endogenous α2 adrenergic receptor. To determine which Gα proteins may be natively expressed in SCG neurons, the presence of mRNA for various Gα proteins was tested using reverse transcription-polymerase chain reaction. Strong bands were detected for all members of the Gi/o family (Gαo, Gαi1, Gαi2, Gαi3, Gαz) as well as for Gα11 and Gαs. A weak signal was detected for Gαq and no Gα15 mRNA was detected.