Identification of a signal-transduction pathway shared by haematopoietic growth factors with diverse biological specificity.
The haematopoietic growth factors multi-colony-stimulating factor, granulocyte/macrophage colony-stimulating factor, granulocyte colony-stimulating factor and interleukin 2 specifically control the production and proliferation of distinct leucocyte series. Each growth factor acts on a unique surface receptor associated with an appropriate signal-transduction apparatus. In this report we identify a 68 kDa substrate which is phosphorylated after stimulation of different cell types with multi-colony-stimulating factor, granulocyte colony-stimulating factor and interleukin 2. The 68 kDa substrate is also phosphorylated in each cell line stimulated with synthetic diacylglycerol, a direct activator of protein kinase C. Interestingly, granulocyte/macrophage colony-stimulating factor does not induce phosphorylation of the 68 kDa molecule. The 68 kDa molecule that is phosphorylated after stimulation with each ligand yielded similar peptide maps after chymotryptic digestion; furthermore, the substrate was always phosphorylated on threonine residues. Phosphorylation of the same residues in the 68 kDa substrate suggests that activation of protein kinase C is one common signal-transduction event associated with the action of multi-colony-stimulating factor, granulocyte colony-stimulating factor and interleukin 2.
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D003115:Colony-Stimulating Factors / Q000494:pharmacology*; D004591:Electrophoresis, Polyacrylamide Gel; D007376:Interleukin-2 / Q000494:pharmacology*; D007700:Kinetics; D051379:Mice; D010446:Peptide Fragments / Q000032:analysis; D010449:Peptide Mapping; D010750:Phosphoproteins / Q000378:metabolism; D010766:Phosphorylation; D011506:Proteins / Q000378:metabolism
D000596:Amino Acids; D003115:Colony-Stimulating Factors; D007376:Interleukin-2; D010446:Peptide Fragments; D010750:Phosphoproteins; D011506:Proteins