This protein is associated with mitochondrial Complex I intermediate-associated protein 30 (CIA30) in human and mouse. The family is also present in Schizosaccharomyces pombe which does not contain the NADH dehydrogenase component of complex I, or many of the other essential subunits. This means it is possible that this family of protein may not be directly involved in oxidative phosphorylation [1][2].

1: CIA30 complex I assembly factor: a candidate for human complex I deficiency?. Janssen R, Smeitink J, Smeets R, van Den Heuvel L; Hum Genet 2002;110:264-270. PMID:11935339

2: Sequences of 20 subunits of NADH:ubiquinone oxidoreductase from bovine heart mitochondria. Application of a novel strategy for sequencing proteins using the polymerase chain reaction. Walker JE, Arizmendi JM, Dupuis A, Fearnley IM, Finel M, Medd SM, Pilkington SJ, Runswick MJ, Skehel JM; J Mol Biol 1992;226:1051-1072. PMID:1518044