Functional regulation of metabotropic glutamate receptor type 1c: a role for phosphorylation in the desensitization of the receptor.
The phosphorylation and desensitization of metabotropic glutamate receptor type 1c in response to agonist and phorbol esters has been studied. Specific immunoprecipitation of mGluR1c from cells treated with agonist or PMA showed a time-dependent increase in the phosphorylation of a membrane protein with the same molecular weight as the dimeric form of the receptor. Measurements of inositol phosphate production showed a rapid functional desensitization of about 90% after agonist treatment, whereas treatment with PMA caused only a 30% loss in the same time. The extent of receptor phosphorylation following the different treatments paralleled the desensitization of the receptor. These results strongly suggest that phosphorylation of the dimeric form of mGluR1c, as a functionally active form, may play a role in its rapid desensitization.
Ciruela
F
F
Medical Research Council Anatomical Neuropharmacology Unit, Oxford, UK.
Giacometti
A
A
McIlhinney
R A
RA
D000818:Animals; D019921:Biotinylation; D016466:CHO Cells; D006224:Cricetinae; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007211:Indoles / Q000494:pharmacology; D007295:Inositol Phosphates / Q000378:metabolism; D007700:Kinetics; D008565:Membrane Proteins / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D011487:Protein Conformation; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D016318:Quisqualic Acid / Q000494:pharmacology; D018094:Receptors, Metabotropic Glutamate / Q000737:chemistry* / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors; D014162:Transfection
D004791:Enzyme Inhibitors; D007211:Indoles; D007295:Inositol Phosphates; D008565:Membrane Proteins; D018094:Receptors, Metabotropic Glutamate; D016318:Quisqualic Acid; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate; C064758:Ro 31-8220