Foetal calf serum enhances cholera toxin-catalysed ADP-ribosylation of the pertussis toxin-sensitive guanine nucleotide binding protein, Gi2, in rat glioma C6BU1 cells.
The major G-protein of rat glioma C6BU1 cells corresponds immunologically to Gi2. In the absence of guanine nucleotides, this protein is shown to be a substrate for ADP-ribosylation catalysed by both cholera and pertussis toxins. Under these conditions, a receptor for a growth factor, which has previously been shown to be activated by foetal calf serum, modulated the effects of both cholera and pertussis toxins on the G-protein. These ligand-mediated alterations of cholera and pertussis toxin-catalysed ADP ribosylation demonstrate that, in this system, the growth factor receptor interacts functionally with Gi2.
Milligan
G
G
Department of Biochemistry, University of Glasgow, Scotland.
D020727:ADP-Ribosylation Factors; D000246:Adenosine Diphosphate Ribose / Q000378:metabolism*; D000818:Animals; D002772:Cholera Toxin / Q000494:pharmacology*; D020558:GTP Phosphohydrolases / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D005910:Glioma / Q000378:metabolism*; D006133:Growth Substances / Q000097:blood*; D008970:Molecular Weight; D009243:NAD / Q000378:metabolism; D037342:Pertussis Toxin; D010761:Phosphorus Radioisotopes; D051381:Rats; D014407:Tumor Cells, Cultured; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D006133:Growth Substances; D010761:Phosphorus Radioisotopes; D010566:Virulence Factors, Bordetella; D009243:NAD; D000246:Adenosine Diphosphate Ribose; D002772:Cholera Toxin; D037342:Pertussis Toxin; D020558:GTP Phosphohydrolases; D019204:GTP-Binding Proteins; D020727:ADP-Ribosylation Factors