Isolation and characterization of transfer RNAs from Dictyostelium discoideum during growth and development.

Transfer RNAs and aminoacyl-tRNA synthetases were isolated from vegetative and developing cells of the cellular slime mode Dictyostelium discoideum. Using the homologous synthetases, the tRANs were compared for their levels of acceptance of 17 amino acids. These levels were found to be the same. The tRANs were further compared by double label chromatography on reversed phase columns. Some major quantitative differences in individual peaks were observed. In addition, for a number of aminoacyl-tRNAs, small but reproducible displacements of individual peaks were apparent. In many cases the displacement was in the major peak, and in all but one case the developmental peak eluted ahead of the vegetative peak. Taken together, these results suggest that there is no change from growth to development in the transcription of tRNA genes, but that there are important changes in post-transcriptional modification.