The tRNA genes punctuate the reading of genetic information in human mitochondrial DNA

Large gene overlaps and tRNA processing in the compact mitochondrial genome of the crustaceanArmadillidium vulgare

“…5A), primary transcripts are processed by precise endonucleolytic cleavages by RNases P and Z before and after each tRNA to release mature mRNAs. [2][3][4] These mRNAs possess no significant 5 0 UTR and several of them require polyadenylation to create a functional stop codon. 5 As described above, the tRNA punctuation model can be applied to several A. vulgare genes ( Fig.…”

“…The tRNAs are processed by RNases P and Z, thus excising mRNAs. [2][3][4] When mRNAs are incomplete, polyadenylation is used to create a stop codon, and mRNA is translated. 5 In A. vulgare, this tRNA punctuation model is valid for part of the RNAs, including the tRNA VaL-Ala (V-A in the gray box), adjacent of the nad3 gene.…”

“…Many mRNA (mRNA) coding sequences are immediately adjacent at their 3 0 end to tRNA genes and according to the tRNA punctuation model, primary transcripts are processed by precise endonucleolytic cleavages by RNases P and Z before and after each tRNA to release mature rRNAs and mRNAs. [2][3][4] In addition, several mRNAs excised from the precursor molecules end with U or UA at their 3 0 -termini, and require polyadenylation to create a functional stop codon. 5 The 5 0 extremity of mature mRNAs usually begins with the initiation codon and there is usually no 5 0 UTR.…”

Genetic aspects of mitochondrial genome evolution

“…This processing, which is known as the RNA punctuation model (Ojala et al, 1980), is mediated by RNase P and tRNase Z endonucleases, respectively (Levinger et al, 2004). When multiple tRNA genes are present, as between nad3 and nad5…”

The complete mitochondrial genome of Cephalothrix simula (Iwata) (Nemertea: Palaeonemertea)

“…2). When two protein-coding genes abut directly, as seen in the gene pairs nad6/cox3 and coxl/cox2 of C. Simula, both are postulated to be translated from the same bicistronic message (Ojala et al, 1980).…”