A cluster of six tRNA genes in Drosophila mitochondrial DNA that includes a gene for an unusual tRNAserAGY

摘要: Genes for URF3, tRNAala, tRNAarg, tRNAasn, tRNAserAGY, tRNAglu, tRNAphe, and the carboxyl terminal segment of URF5 gene have been identified within a sequenced mtDNA molecule Drosophila yakuba. The genes occur in order given. tRNAphe are transcribed same direction as replication while URF3 remaining five tRNA opposite direction. Considerable differences exist relative arrangement these D. yakuba mammalian molecules. In tRNAserAGY an eleven nucleotide loop, which secondary structure formation seems unlikely, replaces dihydrouridine arm, both variable loop (six nucleotides) T phi C (nine larger than any other gene. As available evidence is consistent with AGA codons specifying serine rather arginine mitochondrial genetic code, possibility considered that 5'GCU anticodon can recognize well AGY codons.