Core component of the MITRAC (mitochondrial translation regulation assembly intermediate of cytochrome c oxidase complex) complex, that regulates cytochrome c oxidase assembly. Requires for coordination of the early steps of cytochrome c oxidase assembly with the synthesis of MT-CO1. Along with COA3, core component of the MITRAC (mitochondrial translation regulation assembly intermediate of cytochrome c oxidase complex) complex. The disease may be caused by variants affecting the gene represented in this entry.