THE DROSOPHILA-MELANOGASTER RIBOSOMAL-PROTEIN L17A-ENCODING GENE

The structure and sequence of the gene encoding the Drosophila melanogaster homolog of the human and yeast large-subunit ribosomal protein L17A (rpL17A) is presented. The deduced amino acid (aa) sequence of 140 residues exhibits 87% and 77% identity to that of the human (140 aa) and yeast (137 aa) rpL17As, respectively. The D. melanogaster rpL17A gene is single copy and maps at 58F6-59A3, a chromosome region encompassing a previously characterized Minute locus, M(2)I. Despite this extensive homology in their protein products, the D. melanogaster and yeast rpL17A genes display different exon-intron structures, with the first D. melanogaster intron mapping within the 5'-untranslated mRNA leader. The rpL17A gene gives rise to a single 600-nucleotide transcript present throughout development, and is located close to another similarly expressed gene. The 5' end of the D. melanogaster rpL17A mRNA contains a polypyrimidine tract displayed by several mammalian rp genes and involved in translational control of their expression.