Acts as an assembly factor for mitochondrial respiratory complexes. Interacts with NDUFS3, NDUFA4, NDUFV1, NDUFA9 and NDUFS8 of the mitochondrial membrane respiratory chain NADH dehydrogenase (Complex I) (PubMed:31536960). Interacts with UQCRC2 of the ubiquinol-cytochrome c reductase complex (Complex III) (PubMed:31536960). Interacts with COX5A and COX7C of the cytochrome c oxidase complex (Complex IV) (PubMed:31536960). Experimental confirmation may be lacking for some isoforms. Expressed in embryonic stem cells and differentiated neuronal cells. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay.