title: Product of the cellular oncogene, c-fos, observed in mouse and human tissues using an antibody to a synthetic peptide.
abstract: The transforming gene of the osteosarcoma-producing FBJ murine sarcoma virus, v-fos, is homologous to a normal cellular gene, c-fos, in vertebrate species. Transcripts from the c-fos proto-oncogene accumulate to very high levels in late gestational mouse and human extra-embryonic tissues. We now report that these RNA transcripts are translated in these tissues. Rabbits were immunized with a synthetic peptide whose sequence is common to both c-fos and v-fos. After affinity purification on an immunosorbent containing the fos peptide (a nonapeptide), the antibody reacted with a component(s) in nuclei in sections of human and murine tissues and immunoprecipitated the v-fos gene product (p55) and a cellular protein of 39 kd (p39, complexed with fos) from lysates of metabolically-labelled virally transformed cells. Crude extracts of normal tissues contained major anti-fos-reactive proteins in the range of 55-60 kd as shown by protein blot analysis. Indirect immunofluorescence and immunoperoxidase staining showed that in addition to strong immunoreactive component(s) in the nuclei of extra-embryonic tissues of human and mouse, weaker reactions are detectable in all normal fetal and adult tissues tested. This demonstrates that fos-reactive protein is expressed in a wide variety of cells and tissues.
mesh_terms: D000595:Amino Acid Sequence; D000650:Amnion / Q000166:cytology; D000818:Animals; D000906:Antibodies; D001483:Base Sequence; D002471:Cell Transformation, Neoplastic; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D051379:Mice; D008970:Molecular Weight; D009857:Oncogenes; D012516:Osteosarcoma / Q000235:genetics*; D010920:Placenta / Q000166:cytology; D011247:Pregnancy; D014176:Protein Biosynthesis; D000090063:Proto-Oncogene Mas; D014018:Tissue Distribution; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000032:analysis / Q000235:genetics*
chemical_list: D000906:Antibodies; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D014764:Viral Proteins