Neurospora crassa mitochondrial transfer RNAs

Hamster mitochondrial transfer RNA lacks T and the universal GUUCG sequence

Earlier inferences (based on incorporation of radio-activity from methyl-labeled methionine) that mammalian mitochondrial tRNA lacks ribothymidine ('T') have been confirmed using [14C]uridine as precursor. Moreover, oligonucleotide fingerprint analysis of 32P-labeled samples have shown that hamster mitochondrial tRNA lacks the 'universal' pentanucleotide of conventional tRNA in which T normally occurs, CTpsiCG, in modified or unmodified form.

The genetic map of transfer RNA genes of yeast mitochondria: correction and extension

Ninety five rho- mitochondrial DNA's of Saccharomyces cerevisiae were compared for their deletion structure by means of 15 genetic markers and 22 tRNA genes. The patterns of co-deletion and co-retention of different tRNA genes allowed us to determine their positions with respect to each other. The deduced order of tRNA genes was consistent with the order of the genetic markers established by independent genetic approaches. Our previously proposed mitochondrial tRNA gene map has been revised and extended. Transfer RNA genes, corresponding to all 20 aminoacids, and two isoacceptor tRNA genes were localized. The possible position of each tRNA gene has been indicated on the physical map of mitochondrial DNA. Seventeen tRNA genes are carried by a narrow region representing less than 20% of the wild type genome.