Characterization of the human c-fms gene product and its expression in cells of the monocyte-macrophage lineage.
The McDonough strain of feline sarcoma virus contains an oncogene called v-fms whose ultimate protein product (gp140v-fms) resembles a cell surface growth factor receptor. To identify and characterize the protein product of the proto-oncogene c-fms, antisera were prepared to the viral fms sequences and used to detect specific cross-reacting sequences in human choriocarcinoma cells (BeWo) known to express c-fms mRNA. Both tumor-bearing rat sera and a rabbit antiserum prepared to a segment of v-fms expressed in Escherichia coli detected a 140-kilodalton (kDa) glycoprotein in the BeWo cells. Tryptic fingerprint analysis of [35S]methionine-labeled proteins indicated that the viral fms proteins and the 140-kDa BeWo cell protein were highly related. This 140-kDa glycoprotein contained an associated tyrosine kinase activity in vitro and was labeled principally on serine after 32Pi metabolic labeling. These results suggest that the 140-kDa protein in BeWo cells is the protein product of the human c-fms proto-oncogene. This conclusion is supported by the finding that a similar protein is detectable only in other human cells that express c-fms mRNA. These other human cells include adherent monocytes and the cell line ML-1, which can be induced to differentiate along the monocyte-macrophage pathway. This is in agreement with current thought that the c-fms proto-oncogene product functions as the CSF-1 receptor specific to this pathway.
D000941:Antigens / Q000276:immunology; D003429:Cross Reactions; D005786:Gene Expression Regulation; D006801:Humans; D008264:Macrophages / Q000378:metabolism*; D009000:Monocytes / Q000378:metabolism*; D009856:Oncogene Proteins, Viral / Q000276:immunology; D011505:Protein-Tyrosine Kinases / Q000235:genetics; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology; D011519:Proto-Oncogenes; D012333:RNA, Messenger / Q000235:genetics; D005253:Sarcoma Viruses, Feline / Q000235:genetics / Q000276:immunology
D000941:Antigens; C000715470:MAS1 protein, human; D009856:Oncogene Proteins, Viral; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D011505:Protein-Tyrosine Kinases