This gene encodes a ubiquinone-binding protein of low molecular mass. It is a small core-associated protein and a subunit of ubiquinol-cytochrome c reductase complex III, which is part of the mitochondrial respiratory chain.[5]
Clinical significance
Variants of UQCRQ have been associated with complex III deficiency. One set of twenty consanguineous cases of a Ser45Phe mutation in the UQCRQ gene, and a different homozygous 4-bp deletion at p. 338-341, have been linked to this disease. In an inbred Israeli Bedouin family, the mutations, inherited in an autosomal recessive pattern, displayed the phenotype of mitochondrial Complex III deficiency, nuclear type 4, accompanied by severe neurological symptoms.[6] Other symptoms of complex III deficiency linked to these mutations have included hypoglycemia, lactic acidosis, and hypotonia.[12]
In another study of cardiac muscle tissue in individuals infected by Trypanosoma cruzi, an oxidative modification of the UQCRQ subunit was present, along with oxidative modification of subunits UQCRC1 and UQCRC2 of the same core complex and UQCRH and CYC1 of the neighboring subcomplex.[7]
^Usui S, Yu L, Yu CA (May 1990). "The small molecular mass ubiquinone-binding protein (QPc-9.5 kDa) in mitochondrial ubiquinol-cytochrome c reductase: isolation, ubiquinone-binding domain, and immunoinhibition". Biochemistry. 29 (19): 4618–26. doi:10.1021/bi00471a017. PMID2164842.
^Haut S, Brivet M, Touati G, Rustin P, Lebon S, Garcia-Cazorla A, Saudubray JM, Boutron A, Legrand A, Slama A (July 2003). "A deletion in the human QP-C gene causes a complex III deficiency resulting in hypoglycaemia and lactic acidosis". Human Genetics. 113 (2): 118–22. doi:10.1007/s00439-003-0946-0. PMID12709789. S2CID24273072.
Schägger H, Brandt U, Gencic S, von Jagow G (1995). "[7] Ubiquinol-cytochrome-c reductase from human and bovine mitochondria". Ubiquinol-cytochrome-c reductase from human and bovine mitochondria. Methods in Enzymology. Vol. 260. pp. 82–96. doi:10.1016/0076-6879(95)60132-5. ISBN9780121821616. PMID8592474.
Sifroni KG, Damiani CR, Stoffel C, Cardoso MR, Ferreira GK, Jeremias IC, Rezin GT, Scaini G, Schuck PF, Dal-Pizzol F, Streck EL (September 2010). "Mitochondrial respiratory chain in the colonic mucosal of patients with ulcerative colitis". Molecular and Cellular Biochemistry. 342 (1–2): 111–5. doi:10.1007/s11010-010-0474-x. PMID20440543. S2CID34103232.