Transcriptional and posttranscriptional modulation of myeloid colony-stimulating factor expression by tumor necrosis factor and other agents.
AUTOR(ES)
Koeffler, H P
RESUMO
Granulocyte (G) and granulocyte-macrophage (GM) colony-stimulating factors (CSF) are necessary for proliferation and differentiation of myeloid hematopoietic cells. Fibroblasts stimulated by tumor necrosis factor alpha (TNF alpha) and several other agents are a rich source of these CSF. The GM-CSF synthesized by these cells had the same molecular weight and glycosylation pattern as that produced by activated T lymphocytes, as shown by [35S]methionine labeling studies. Northern (RNA) blot analysis showed that the fibroblasts had trace levels of G- and GM-CSF mRNA. Both G- and GM-CSF mRNA concentrations coordinately increased after exposure of the cells to TNF alpha (greater than or equal to 5 ng/ml), 12-O-tetradecanoylphorbol 13-acetate (TPA) (greater than or equal to 5 x 10(-10) M), or cycloheximide (20 micrograms/ml). Both TNF alpha and TPA increased levels of G- and GM-CSF mRNA in the absence of new protein synthesis. Transcriptional run-on studies demonstrated that fibroblasts constitutively transcribed GM-CSF, and transcription was enhanced 3.0-fold by TNF alpha and 2.5-fold by TPA and was unchanged by cycloheximide. The stability of G- and GM-CSF transcripts was determined after exposure of the cells to actinomycin D; the half-lives of G- and GM-CSF mRNA in unstimulated cells were less than 0.25 h and were increased 2- to 16-fold in cells cultured with TNF, TPA, or cycloheximide. In summary, both transcriptional and posttranscriptional signals acted coordinately to modulate the levels of G- and GM-CSF mRNAs in fibroblasts.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=363580Documentos Relacionados
- Induction of junB expression, but not c-jun, by granulocyte colony-stimulating factor or macrophage colony-stimulating factor in the proliferative response of human myeloid leukemia cells.
- Modulation of Mycobacterium lepraemurium growth in murine macrophages: beneficial effect of tumor necrosis factor alpha and granulocyte-macrophage colony-stimulating factor.
- Effects of Granulocyte-Macrophage Colony-Stimulating Factor and Tumor Necrosis Factor Alpha on Trypanosoma cruzi Trypomastigotes
- Alteration of the functional effects of granulocyte-macrophage colony-stimulating factor on polymorphonuclear leukocytes by membrane-fluidizing agents.
- Transcriptional and posttranscriptional regulation of macrophage-specific colony stimulating factor gene expression by tumor necrosis factor. Involvement of arachidonic acid metabolites.