UQCRQ
Ubiquinol-cytochrome c reductase, complex III subunit VII, 9.5kDa is a protein that in humans is encoded by the UQCRQ gene. This ubiqinone-binding protein is a subunit of mitochondrial Complex III in the electron transport chain.[5] A mutation in the UQCRQ gene has been shown to cause severe neurological disorders.[6] Infection by Trypanosoma cruzi can cause oxidative modification of this protein in cardiac muscle tissue.[7]
Structure
The UQCRQ gene is located on the q arm of chromosome 5 in position 31.1 and spans 2,217 base pairs.[8] The gene produces a 9.9 kDa protein composed of 82 amino acids.[9][10] This protein is transmembranous, with more mass on the matrix side of the membrane.[11]
Function
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]
Interactions
The protein encoded by UQCRQ has protein-protein interactions with UQCRC1, OPTN, ERCC8, GRINL1A, Dctn1, K8.1, XRCC3, PML, RAB7A, HNRNPA1L2, CDC73, NLRP3, HAUS2, TMEM248, and GOLT1B.[13]
References
- GRCh38: Ensembl release 89: ENSG00000164405 - Ensembl, May 2017
- GRCm38: Ensembl release 89: ENSMUSG00000044894 - Ensembl, May 2017
- "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
- "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
- "Entrez Gene: Ubiquinol-cytochrome c reductase, complex III subunit VII, 9.5kDa". This article incorporates text from this source, which is in the public domain.
- Barel O, Shorer Z, Flusser H, Ofir R, Narkis G, Finer G, Shalev H, Nasasra A, Saada A, Birk OS (May 2008). "Mitochondrial complex III deficiency associated with a homozygous mutation in UQCRQ". American Journal of Human Genetics. 82 (5): 1211–6. doi:10.1016/j.ajhg.2008.03.020. PMC 2427202. PMID 18439546.
- Wen JJ, Garg N (December 2004). "Oxidative modification of mitochondrial respiratory complexes in response to the stress of Trypanosoma cruzi infection". Free Radical Biology & Medicine. 37 (12): 2072–81. doi:10.1016/j.freeradbiomed.2004.09.011. PMID 15544925.
- "Entrez Gene: Ubiquinol-cytochrome c reductase, complex III subunit VII, 9.5kDa".
- Zong NC, Li H, Li H, Lam MP, Jimenez RC, Kim CS, Deng N, Kim AK, Choi JH, Zelaya I, Liem D, Meyer D, Odeberg J, Fang C, Lu HJ, Xu T, Weiss J, Duan H, Uhlen M, Yates JR, Apweiler R, Ge J, Hermjakob H, Ping P (October 2013). "Integration of cardiac proteome biology and medicine by a specialized knowledgebase". Circulation Research. 113 (9): 1043–53. doi:10.1161/CIRCRESAHA.113.301151. PMC 4076475. PMID 23965338.
- "UQCRQ - Cytochrome b-c1 complex subunit 8". Cardiac Organellar Protein Atlas Knowledgebase (COPaKB).
- 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. PMID 2164842.
- 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. PMID 12709789. S2CID 24273072.
- IntAct. "Interactions with UQCRQ". www.ebi.ac.uk. Retrieved 2018-08-02.
Further reading
- Schägger H, Brandt U, Gencic S, von Jagow G (1995). "Ubiquinol-cytochrome-c reductase from human and bovine mitochondria". Methods in Enzymology. 260: 82–96. doi:10.1016/0076-6879(95)60132-5. ISBN 9780121821616. PMID 8592474.
- 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. PMID 20440543. S2CID 34103232.
This article incorporates text from the United States National Library of Medicine, which is in the public domain.