Abstract
Post-transcriptional controls, including changes in both mRNA translational activity and stability, play an important role in the regulation of ribosomal protein gene expresssion in developing Dictyostelium discoideum cells. Previously we have shown that the mechanisms which regulate the translational activity of the r-protein mRNAs operate at the level of translational initiation and do not involve changes in polyadenylation or capping. By analysing the translational behavior of chimeric and mutant mRNAs in transformed cells, we have now been able to localize the determinants of translational activity of one of the r-protein rRNAs to the 5'-untranslated region.