Its gene product is a subunit of the respiratory chain protein Ubiquinol Cytochrome c Reductase (UQCR, Complex III or Cytochrome bc1 complex), which consists of the products of one mitochondrially encoded gene, MTCYTB (mitochondrial cytochrome b) and ten nuclear genes: UQCRC1, UQCRC2, Cytochrome c1, UQCRFS1 (Rieske protein), UQCRB, UQCRQ ("11kDa protein"), UQCRH (cyt c1 Hinge protein), Rieske Protein presequence, UCRC("cyt. c1 associated protein"), and UQCR ("Rieske-associated protein").Schagger et al. (1995) isolated the 7.2-kD subunit of bovine and human mitochondrial complex III, which they called cytochrome C1 (CYC1; 123980)-associated protein.The International Radiation Hybrid Mapping Consortium mapped the UCRC gene to chromosome 22 (STS-AA025006).