Regulation of platelet-derived growth factor A messenger RNA translation in differentiating F9 teratocarcinoma cells.

We have monitored production of platelet-derived growth factor (PDGF) in F9 teratocarcinoma cells. We show that undifferentiated F9 cells express PDGF A mRNA and produce biologically active PDGF AA homodimers. When differentiation is induced by treatment with retinoic acid and cyclic AMP, the production of PDGF AA protein is terminated. Contrary to expectation, inhibition of PDGF synthesis is exerted at a posttranscriptional level. Both undifferentiated and differentiated (1 day) F9 cell cultures contain comparable amounts of PDGF A mRNA. However, this mRNA becomes dissociated from polysomes during F9 cell differentiation.