Platelet-derived growth factor does not induce c-fos in NIH 3T3 cells expressing the EJ-ras oncogene.
Platelet-derived growth factor (PDGF), the calcium ionophore A23187, and the tumor promoter phorbol myristate acetate stimulated c-fos mRNA levels in control NIH 3T3 cells. However, NIH 3T3 cells transformed by EJ-ras DNA transfection, which have diminished PDGF-stimulated phospholipase C activity, showed a 95% reduction in PDGF-stimulated c-fos mRNA levels. The responses to A23187 and phorbol myristate acetate were also attenuated, but not as severely as the PDGF-mediated induction. The reduction in PDGF-stimulated c-fos induction did not appear to be a general result of cellular transformation, since src-transformed NIH 3T3 cells displayed a strong PDGF-stimulated c-fos induction. Despite the reduction in PDGF-stimulated c-fos induction, EJ-ras-transformed cells still responded mitogenically to PDGF. These data suggest that the magnitude of c-fos induction cannot be directly correlated with PDGF-stimulated mitogenesis in EJ-ras-transformed NIH 3T3 cells.
Lin
A H
AH
Cell Biology Department, Upjohn Company, Kalamazoo, Michigan 49001.
Groppi
V E
VE
Gorman
R R
RR
D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D002461:Cell Line, Transformed; D011905:Genes, ras; D006801:Humans; D008934:Mitogens; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology*; D011519:Proto-Oncogenes / Q000187:drug effects*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013936:Thymidine / Q000378:metabolism; D010738:Type C Phospholipases / Q000378:metabolism
D008934:Mitogens; D010982:Platelet-Derived Growth Factor; D012333:RNA, Messenger; D000001:Calcimycin; D010738:Type C Phospholipases; D013755:Tetradecanoylphorbol Acetate; D013936:Thymidine