Efficient translation of mitochondrial-derived transcripts requires proper assembly of the large subunit of the mitochondrial ribosome. Central to the biogenesis of this large subunit is the A-loop of mitochondrial 16S rRNA, which is modified by three rRNA methyltransferases located near mtDNA nucleoids. The protein encoded by this gene methylates G(1370) of 16S rRNA, and this modification is necessary for proper ribosomal large subnit assembly. Two transcript variants encoding different isoforms have been found for this gene.