tRNA (cytosine(34)-C(5))-methyltransferase, mitochondrial (NSUN3)

Mitochondrial tRNA methyltransferase that mediates methylation of cytosine to 5-methylcytosine (m5C) at position 34 of mt-tRNA(Met) (PubMed:27497299, PubMed:27214402, PubMed:27356879). Mt-tRNA(Met) methylation at cytosine(34) takes place in the wobble position of the anticodon and begins the formation of 5-formylcytosine (f(5)c) at this position (PubMed:27497299, PubMed:27214402, PubMed:27356879).

Mt-tRNA(Met) containing the f(5)c adjustment at the wobble position allows recognition of the AUA codon along with the AUG codon, expanding codon recognition in mitochondrial translation (PubMed:27497299, PubMed:27356879). .