Endogenous RGS proteins facilitate dopamine D(2S) receptor coupling to G(alphao) proteins and Ca2+ responses in CHO-K1 cells.
The role of RGS proteins on dopaminergic D2S receptor (D2SR) signalling was investigated in Chinese hamster ovary (CHO)-K1 cells, using recombinant RGS protein- and PTX-insensitive G alphao proteins. Dopamine-mediated [35S]GTPgammaS binding was attenuated by more than 60% in CHO-K1 D2SR cells coexpressing a RGS protein- and PTX-insensitive G(alphao)Gly184Ser:Cys351Ile protein versus cells coexpressing a similar amount of PTX-insensitive G alphaoCys351Ile protein. Dopamine-agonist-mediated Ca2+ responses were dependent on the coexpression with a G alphao Cys351Ile protein and were fully abolished upon coexpression with a G alphaoGly184Ser:Cys351Ile protein. These results suggest that interactions between the G alphao protein and RGS proteins are involved in efficient D2SR signalling.
Boutet-Robinet
Elisa A
EA
Department of Cellular and Molecular Biology, Centre de Recherche Pierre Fabre, 17 avenue Jean Moulin, 81106 Cedex, Castres, France.
Finana
Frederic
F
Wurch
Thierry
T
Pauwels
Petrus J
PJ
De Vries
Luc
L
D000818:Animals; D001058:Apomorphine / Q000031:analogs & derivatives* / Q000494:pharmacology; D016466:CHO Cells; D020013:Calcium Signaling; D006224:Cricetinae; D004298:Dopamine / Q000494:pharmacology; D019206:GTP-Binding Protein alpha Subunits, Gi-Go; D020962:Heterotrimeric GTP-Binding Proteins / Q000378:metabolism*; D006801:Humans; D037342:Pertussis Toxin / Q000494:pharmacology; D020710:RGS Proteins / Q000378:metabolism*; D017448:Receptors, Dopamine D2 / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D015398:Signal Transduction
D020710:RGS Proteins; D017448:Receptors, Dopamine D2; D011994:Recombinant Proteins; C113776:dopamine D2L receptor; C009074:N-n-propylnorapomorphine; D037342:Pertussis Toxin; D019206:GTP-Binding Protein alpha Subunits, Gi-Go; D020962:Heterotrimeric GTP-Binding Proteins; D001058:Apomorphine; D004298:Dopamine