title: Defects of cyclic adenosine 3':5'-monophosphate-dependent protein kinases in initiated clones derived from BALB/c 3T3 mouse fibroblasts.
abstract: Two-stage carcinogenesis is involved in the transformation of mouse fibroblasts BALB/c 3T3 cells. In order to investigate the role of cyclic adenosine 3':5'-monophosphate (cAMP)-dependent protein kinase at the stage of initiation, the following experiments were carried out: (a) two initiated clones (M14, M20) which exhibit 12-O-tetradecanoylphorbol-13-acetate-dependent growth in soft agar medium were isolated from cells treated with N-methyl-N'-nitro-N-nitrosoguanidine. The activity of cAMP-dependent protein kinase in M14 was reduced while that in M20 was similar to the level in parental cells. However, cAMP-binding activity to a regulatory subunit of cAMP-resistant clones were isolated from 4-nitroquinoline oxide- or ethyl methanesulfonate-treated cells. These clones have reduced activities in both cAMP-binding and cAMP-dependent protein kinase itself. Two of three cAMP-resistant clones were proved to be able to grow in soft agar medium only in the presence of 12-O-tetradecanoylphorbol-13-acetate.
mesh_terms: D015112:4-Nitroquinoline-1-oxide / Q000494:pharmacology; D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000201:enzymology; D002999:Clone Cells / Q000201:enzymology*; D000242:Cyclic AMP / Q000378:metabolism; D005020:Ethyl Methanesulfonate / Q000494:pharmacology; D005347:Fibroblasts / Q000201:enzymology; D008769:Methylnitronitrosoguanidine / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D011494:Protein Kinases / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D008769:Methylnitronitrosoguanidine; D015112:4-Nitroquinoline-1-oxide; D005020:Ethyl Methanesulfonate; D000242:Cyclic AMP; D011494:Protein Kinases; D013755:Tetradecanoylphorbol Acetate