Tyrosine phosphorylation of a common 57-kDa protein in growth factor-stimulated and -transformed cells.
Protein tyrosine phosphorylation was studied in macrophages and fibroblasts to identify putative components of post-receptor mitogenic pathways that might be functionally conserved in different cell types. Nondenaturing conditions were established for the approximately quantitative recovery of anti-phosphotyrosine antibody (alpha PY)-reactive proteins from cells. A common, 57-kDa alpha PY-reactive protein was identified by V8 protease peptide mapping in colony-stimulating factor-1 (CSF-1)- or granulocyte-macrophage colony-stimulating factor (GM-CSF)-stimulated BAC1.2F5 macrophages, in platelet-derived growth factor-stimulated NIH-3T3 cells, and in CSF-1-stimulated NIH-3T3 cells expressing the c-fms/CSF-1 receptor. The 57-kDa protein was phosphorylated on serine and tyrosine and was the only alpha PY-reactive protein band whose phosphorylation was reproducibly increased in GM-CSF-stimulated cells. The effect of the growth factors on the tyrosine phosphorylation of the 57-kDa protein could be mimicked by treatment of the cells with orthovanadate, a phosphotyrosine protein phosphatase inhibitor. In the absence of growth factors, tyrosine phosphorylation of the 57-kDa protein was higher in v-fms or c-fms (F969, S301)-transformed NIH-3T3 cells than in untransformed NIH-3T3 (c-fms) and NIH-3T3 (c-fms, F969) cells. These data indicate that the 57-kDa protein is a common target for growth factor-stimulated tyrosine phosphorylation and potentially important for growth factor mitogenic signaling.
Li
W
W
Department of Developmental Biology and Cancer, Albert Einstein College of Medicine, Bronx, New York 10461.
Yeung
Y G
YG
Stanley
E R
ER
D000818:Animals; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D006133:Growth Substances / Q000494:pharmacology*; D007700:Kinetics; D016173:Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D051379:Mice; D008970:Molecular Weight; D010710:Phosphates / Q000378:metabolism; D010750:Phosphoproteins / Q000302:isolation & purification*; D010766:Phosphorylation; D019000:Phosphotyrosine; D011994:Recombinant Proteins / Q000494:pharmacology; D014443:Tyrosine / Q000031:analogs & derivatives / Q000032:analysis
D006133:Growth Substances; D010710:Phosphates; D010750:Phosphoproteins; D011994:Recombinant Proteins; D019000:Phosphotyrosine; D014443:Tyrosine; D016173:Macrophage Colony-Stimulating Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor