title: Alterations in components of adenylate cyclase associated with transformation of chicken embryo fibroblasts by Rous sarcoma virus.
abstract: Regulation of adenylate cyclase coincident with transformation of chicken embryo fibroblasts by Rous sarcoma virus is manifest as a 10-50% decrease in basal, Mg2+-, and forskolin-stimulated activities; activities elicited by fluoride and guanosine 5'-O-(3-thiotriphosphate) are unaltered. The level of the catalytic component of adenylate cyclase, assessed with activated stimulatory guanine nucleotide-binding protein (Gs), increases approximately 1.5-fold. The level of the beta subunit common to Gs and the inhibitory regulatory protein assessed by enzyme-linked immunotransfer blotting, increases 2.7-fold. The isoelectric behavior of the beta subunit is unaltered. The amount of radiolabel incorporated into the alpha subunit of Gs (Mr = 45,000) upon incubation of membranes with 32P-labeled NAD and cholera toxin increases 3-fold upon transformation. Detergent extracts prepared from membranes of untransformed and transformed fibroblasts nevertheless exhibit equivalent abilities to reconstitute fluoride-stimulated activities to membranes of the cyc-variant of mouse S49 lymphoma cells. Islet-activating protein catalyzes incorporation of radiolabel from 32P-labeled NAD into 39,000- and 41,000-dalton proteins; the extent of radiolabel incorporation does not change upon transformation. Modest alterations in the isoelectric behaviors of substrates for cholera toxin and islet-activating protein occur.
mesh_terms: D037361:Adenylate Cyclase Toxin; D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D001358:Avian Sarcoma Viruses; D002472:Cell Transformation, Viral; D002642:Chick Embryo; D002772:Cholera Toxin / Q000494:pharmacology; D005576:Colforsin / Q000494:pharmacology; D004797:Enzyme-Linked Immunosorbent Assay; D005347:Fibroblasts / Q000201:enzymology; D005459:Fluorides / Q000494:pharmacology; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D006160:Guanosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D037342:Pertussis Toxin; D013873:Thionucleotides / Q000494:pharmacology; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
chemical_list: D037361:Adenylate Cyclase Toxin; D013873:Thionucleotides; D010566:Virulence Factors, Bordetella; D005576:Colforsin; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D006160:Guanosine Triphosphate; D002772:Cholera Toxin; D037342:Pertussis Toxin; D000262:Adenylyl Cyclases; D005459:Fluorides