The nuclear PET122 gene of S. cerevisiae encodes a mitochondrial-localised protein that activates initiation of translation of the mitochondrial mRNA from the COX3 gene, which encodes subunit III of cytochrome c oxidase [1].

1: Expression of the divergent transcription unit containing the yeast PET122 and OXA1 genes. Marathe SV, McEwen JE; Biochem Mol Biol Int 1999;47:971-977. PMID:10410243