Association of two pertussis toxin-sensitive G-proteins with the D2-dopamine receptor from bovine striatum.
The solubilized D2-dopamine receptor from bovine striatum exhibits high and low affinity states for dopaminergic agonists. Guanine nucleotides and pertussis toxin convert the solubilized receptor from a high affinity state to a low one. A D2-receptor preparation partially purified by affinity chromatography on a haloperidol adsorbent, exhibited agonist-stimulated GTPase activity. [32P]ADP-ribosylation by pertussis toxin of this receptor preparation resulted in the specific labeling of two protein bands corresponding to mol. wts of 39 and 41 kd, in SDS-PAGE. Association of these G-proteins with the receptor was specifically inhibited by Gpp(NH)p. Immunoblot analysis of these G-proteins indicated that the 41- and 39-kd protein bands are analogous to brain Gi and Go respectively. These experiments demonstrate that two distinct pertussis toxin-sensitive G-proteins are functionally associated with bovine striatum D2-dopamine receptor.
Elazar
Z
Z
Department of Chemical Immunology, Weizmann Institute of Science, Rehovot, Israel.
Siegel
G
G
Fuchs
S
S
D000244:Adenosine Diphosphate / Q000378:metabolism; D000818:Animals; D001058:Apomorphine / Q000031:analogs & derivatives / Q000378:metabolism; D015153:Blotting, Western; D002417:Cattle; D002846:Chromatography, Affinity; D003342:Corpus Striatum / Q000378:metabolism*; D015259:Dopamine Agents / Q000378:metabolism; D020558:GTP Phosphohydrolases / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006150:Guanine Nucleotides / Q000378:metabolism*; D007700:Kinetics; D008566:Membranes / Q000378:metabolism; D037342:Pertussis Toxin; D011954:Receptors, Dopamine / Q000378:metabolism*; D012995:Solubility; D013134:Spiperone / Q000378:metabolism; D010566:Virulence Factors, Bordetella / Q000494:pharmacology*
D015259:Dopamine Agents; D006150:Guanine Nucleotides; D011954:Receptors, Dopamine; D010566:Virulence Factors, Bordetella; D013134:Spiperone; C009074:N-n-propylnorapomorphine; D000244:Adenosine Diphosphate; D037342:Pertussis Toxin; D020558:GTP Phosphohydrolases; D019204:GTP-Binding Proteins; D001058:Apomorphine