Selective decrease in the affinity of D2 dopamine receptor for agonist induced by islet-activating protein, pertussis toxin, associated with ADP-ribosylation of the specific membrane protein of bovine striatum.
When the crude synaptic membrane preparations from bovine striatum were treated with islet-activating protein (IAP), one of the pertussis toxins, a protein with a molecular weight of about 40,000 was ADP-ribosylated. In parallel with this ADP-ribosylation, there was a decrease in D2 dopamine receptor affinity for agonist, while the affinity for antagonist remained unaltered. Addition of GTP to nontreated membranes also resulted in a decrease in the affinity of D2 receptor for agonist, and there was no further reduction of affinity for agonist with addition of GTP to the IAP-treated membranes. As IAP specifically acts on the guanine nucleotide regulatory protein which mediates the inhibition of adenylate cyclase activity (Ni), our findings indicate a possible molecular interaction between the brain D2 dopamine receptor and Ni.
D000246:Adenosine Diphosphate Ribose / Q000378:metabolism*; D037361:Adenylate Cyclase Toxin; D000818:Animals; D001426:Bacterial Proteins / Q000494:pharmacology*; D001427:Bacterial Toxins / Q000494:pharmacology*; D001667:Binding, Competitive; D002417:Cattle; D003342:Corpus Striatum / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006160:Guanosine Triphosphate / Q000494:pharmacology; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007700:Kinetics; D008565:Membrane Proteins / Q000302:isolation & purification / Q000378:metabolism*; D008970:Molecular Weight; D009702:Nucleoside Diphosphate Sugars / Q000378:metabolism*; D037342:Pertussis Toxin; D011954:Receptors, Dopamine / Q000187:drug effects / Q000378:metabolism*; D017448:Receptors, Dopamine D2; D013134:Spiperone / Q000378:metabolism; D013570:Synaptic Membranes / Q000378:metabolism*; D010566:Virulence Factors, Bordetella
D037361:Adenylate Cyclase Toxin; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D007004:Hypoglycemic Agents; D008565:Membrane Proteins; D009702:Nucleoside Diphosphate Sugars; D011954:Receptors, Dopamine; D017448:Receptors, Dopamine D2; D010566:Virulence Factors, Bordetella; D000246:Adenosine Diphosphate Ribose; D013134:Spiperone; D006160:Guanosine Triphosphate; D037342:Pertussis Toxin