title: Modulation of proto-oncogene expression by colony stimulating factors.
abstract: Bone marrow stem cells are dependent upon Colony Stimulating Factors for proliferation in vitro. Using murine myeloid cell lines, which are able to proliferate in culture in the presence of three different murine Colony Stimulating Factors, we have investigated the effect of Colony Stimulating Factors on c-fos and c-myc mRNA induction. Cells were blocked in G1 phase by Colony Stimulating Factor and serum deprivation and allowed to proceed into the cell cycle by addition of Colony Stimulating Factor. Northern analysis of RNA showed that c-fos and c-myc message were induced by the three different Colony Stimulating Factors tested, Interleukin 3, Granulocyte Monocyte-Colony Stimulating Factor and Granulocyte-Colony Stimulating Factor, with similar kinetics and levels of induction. Induction of c-fos mRNA was rapid, transient (with a peak 30 min after induction) and very faint. Accumulation of c-myc (15- to 30-fold) was more stable and quantitatively more important. These results suggests that c-fos and c-myc gene activation is a "consensus" and obligatory event in cell proliferation induction.
mesh_terms: D000818:Animals; D002460:Cell Line; D003115:Colony-Stimulating Factors / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects; D016179:Granulocyte Colony-Stimulating Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D006133:Growth Substances / Q000494:pharmacology*; D007377:Interleukin-3 / Q000494:pharmacology; D051379:Mice; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D011519:Proto-Oncogenes; D012333:RNA, Messenger / Q000235:genetics; D011994:Recombinant Proteins / Q000494:pharmacology; D015533:Transcriptional Activation
chemical_list: D003115:Colony-Stimulating Factors; D006133:Growth Substances; D007377:Interleukin-3; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor