Epidermal and transforming growth factors modulate secretion of a 69 kDa phosphoprotein in normal rat kidney fibroblasts.
Our study shows that the secretion of a major non-glycosylated, phosphoprotein of 69 kDa (pp69) is a specific marker for non-transformed NRK-49F cells. Treatment of NRK-49F cells with EGF alone or with different combinations of EGF plus TGF-beta modulates the secretion of pp69, suggesting its relationship with cellular proliferation. Antibody raised against pp69 recognizes, in addition to pp69, another major phospho-protein of 62 kDa (pp62) secreted by RR1022 and spontaneously transformed NRK-49F cells. Immunoprecipitation of total cell lysates from both NRK-49F and RR1022 cells with anti-pp69 antibody detected only pp69. These observations suggest a precursor-product relationship between pp69 secreted by non-transformed NRK-49F cells and pp62 secreted by transformed cells.
D000818:Animals; D002478:Cells, Cultured; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D007122:Immunoelectrophoresis; D007668:Kidney / Q000378:metabolism*; D010455:Peptides / Q000494:pharmacology*; D010750:Phosphoproteins / Q000378:metabolism*; D051381:Rats; D015291:Transforming Growth Factors
D010455:Peptides; D010750:Phosphoproteins; D004815:Epidermal Growth Factor; D015291:Transforming Growth Factors