Distinctive features of the 5′-terminal sequences of the human mitochondrial mRNAs

@article{Montoya1981DistinctiveFO,
  title={Distinctive features of the 5′-terminal sequences of the human mitochondrial mRNAs},
  author={Julio Montoya and Deanna Ojala and Giuseppe Attardi},
  journal={Nature},
  year={1981},
  volume={290},
  pages={465-470}
}
The 5′-end proximal sequences of all the putative mRNAs coded for by the heavy strand of HeLa cell mitochondrial DNA have been determined and aligned with the DNA sequence. All these mRNAs start directly at, or very near to, an AUG or AUA triplet, with the exception of one which starts at an AUU. The available evidence indicates that the terminal or subterminal AUGs and AUAs, and possibly also the terminal AUU, are initiator codons for the corresponding polypeptides. In most cases, the… 

Lack of secondary structure characterizes the 5' ends of mammalian mitochondrial mRNAs.

It is found that the 5' ends of all mitochondrial mRNAs are highly unstructured, consistent with a model in which the specialized mitochondrial ribosome preferentially allows passage of un Structured 5' sequences into the mRNA entrance site to participate in translation initiation.

Sequence and organization of the human mitochondrial genome

The complete sequence of the 16,569-base pair human mitochondrial genome is presented and shows extreme economy in that the genes have none or only a few noncoding bases between them, and in many cases the termination codons are not coded in the DNA but are created post-transcriptionally by polyadenylation of the mRNAs.

Preferential Selection of the 5′-Terminal Start Codon on Leaderless mRNAs by Mammalian Mitochondrial Ribosomes

It is demonstrated here that mammalian mitochondrial 55 S ribosomes preferentially form initiation complexes at a 5′-terminal AUG codon over an internal AUG, demonstrating that post-transcriptional processing must occur prior to translation in mammalian mitochondria.
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    Proceedings of the National Academy of Sciences of the United States of America
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