Dealing with an Unconventional Genetic Code in  Mitochondria: The Biogenesis and Pathogenic  Defects of the 5-Formylcytosine Modification in  Mitochondrial tRNA(Met).

TitleDealing with an Unconventional Genetic Code in  Mitochondria: The Biogenesis and Pathogenic  Defects of the 5-Formylcytosine Modification in  Mitochondrial tRNA(Met).
Publication TypeJournal Article
Year of Publication2017
AuthorsVan Haute, L, Powell, CA, Minczuk, MA
JournalBiomolecules
Volume7
Issue1
Date Published2017 Mar 02
ISSN2218-273X
Abstract

Human mitochondria contain their own genome, which uses an unconventional genetic code. In addition to the standard AUG methionine codon, the single mitochondrial tRNA Methionine (mt-tRNAMet) also recognises AUA during translation initiation and elongation. Post-transcriptional modifications of tRNAs are important for structure, stability, correct folding and aminoacylation as well as decoding. The unique 5-formylcytosine (f5C) modification of position 34 in mt-tRNAMet has been long postulated to be crucial for decoding of unconventional methionine codons and efficient mitochondrial translation. However, the enzymes responsible for the formation of mitochondrial f5C have been identified only recently. The first step of the f5C pathway consists of methylation of cytosine by NSUN3. This is followed by further oxidation by ABH1. Here, we review the role of f5C, the latest breakthroughs in our understanding of the biogenesis of this unique mitochondrial tRNA modification and its involvement in human disease.

DOI10.3390/biom7010024
Alternate JournalBiomolecules
Citation Key10.3390/biom7010024
PubMed ID28257121
PubMed Central IDPMC5372736
Grant ListMC_U105697135 / / Medical Research Council / United Kingdom