Biology:COX5A
 Generic protein structure example |
Cytochrome c oxidase subunit 5a is a protein that in humans is encoded by the COX5A gene. Cytochrome c oxidase 5A is a subunit of the cytochrome c oxidase complex, also known as Complex IV, the last enzyme in the mitochondrial electron transport chain.[1]
Structure
The COX5A gene, located on the q arm of chromosome 15 in position 24.1, is made up of 5 exons and is 17,880 base pairs in length.[1] The COX5A protein weighs 17 kDa and is composed of 150 amino acids.[2][3] The protein is a subunit of Complex IV, which consists of 13 mitochondrial- and nuclear-encoded subunits.[1]
Function
Cytochrome c oxidase (COX) is the terminal enzyme of the mitochondrial respiratory chain. It is a multi-subunit enzyme complex that couples the transfer of electrons from cytochrome c to molecular oxygen and contributes to a proton electrochemical gradient across the inner mitochondrial membrane to drive ATP synthesis via protonmotive force. The mitochondrially-encoded subunits perform the electron transfer of proton pumping activities. The functions of the nuclear-encoded subunits are unknown but they may play a role in the regulation and assembly of the complex.[1]
Summary reaction:
- 4 Fe2+-cytochrome c + 8 H+in + O2 → 4 Fe3+-cytochrome c + 2 H2O + 4 H+out[4]
Clinical significance
COX5A (this gene) and COX5B are involved in the regulation of cancer cell metabolism by Bcl-2. COX5A interacts specifically with Bcl-2, but not with other members of the Bcl-2 family, such as Bcl-xL, Bax or Bak.[5]
The Trans-activator of transcription protein (Tat) of human immunodeficiency virus (HIV) inhibits cytochrome c oxidase (COX) activity in permeabilized mitochondria isolated from both mouse and human liver, heart, and brain samples.[6]
References
- ↑ 1.0 1.1 1.2 1.3 "Entrez Gene: Cytochrome c oxidase subunit Va". https://www.ncbi.nlm.nih.gov/gene/9377.
- ↑ "Integration of cardiac proteome biology and medicine by a specialized knowledgebase". Circulation Research 113 (9): 1043–53. Oct 2013. doi:10.1161/CIRCRESAHA.113.301151. PMID 23965338.
- ↑ "Cytochrome c oxidase subunit 5a". Cardiac Organellar Protein Atlas Knowledgebase (COPaKB). https://amino.heartproteome.org/web/protein/P20674.
- ↑ Voet, Donald; Voet, Judith G.; Pratt, Charlotte W. (2013). "Chapter 18". Fundamentals of biochemistry: life at the molecular level (4th ed.). Hoboken, NJ: Wiley. pp. 581–620. ISBN 978-0-470-54784-7.
- ↑ "Involvement of cytochrome c oxidase subunits Va and Vb in the regulation of cancer cell metabolism by Bcl-2". Cell Death and Differentiation 17 (3): 408–20. Mar 2010. doi:10.1038/cdd.2009.132. PMID 19834492.
- ↑ "HIV-1 Tat protein directly induces mitochondrial membrane permeabilization and inactivates cytochrome c oxidase". Cell Death & Disease 3 (3): e282. 2012. doi:10.1038/cddis.2012.21. PMID 22419111.
Further reading
- "Cytochrome c oxidase subassemblies in fibroblast cultures from patients carrying mutations in COX10, SCO1, or SURF1". The Journal of Biological Chemistry 279 (9): 7462–9. Feb 2004. doi:10.1074/jbc.M309232200. PMID 14607829.
- "Human liver protein map: update 1993". Electrophoresis 14 (11): 1216–22. Nov 1993. doi:10.1002/elps.11501401181. PMID 8313870.
- "The major protein expression profile and two-dimensional protein database of human heart". Electrophoresis 16 (7): 1160–9. Jul 1995. doi:10.1002/elps.11501601192. PMID 7498159.
- "Binding of proteins to the PDZ domain regulates proteolytic activity of HtrA1 serine protease". The Biochemical Journal 381 (Pt 3): 895–904. Aug 2004. doi:10.1042/BJ20040435. PMID 15101818.
- "Assignment of the human genes coding for cytochrome c oxidase subunits Va (COX5A), VIc (COX6C) and VIIc (COX7C) to chromosome bands 15q25, 8q22-->q23 and 5q14 and of three pseudogenes (COX5AP1, COX6CP1, COX7CP1) to 14q22, 16p12 and 13q14-->q21 by FISH and radiation hybrid mapping". Cytogenetics and Cell Genetics 83 (3–4): 226–7. 1998. doi:10.1159/000015185. PMID 10072584.
- "Genome-wide meta-analysis identifies regions on 7p21 (AHR) and 15q24 (CYP1A2) as determinants of habitual caffeine consumption". PLOS Genetics 7 (4): e1002033. Apr 2011. doi:10.1371/journal.pgen.1002033. PMID 21490707.
- "Subunit Va of human and bovine cytochrome c oxidase is highly conserved". Gene 69 (2): 245–56. Sep 1988. doi:10.1016/0378-1119(88)90435-0. PMID 2853101.
External links
- Human COX5A genome location and COX5A gene details page in the UCSC Genome Browser.
- Mass spectrometry characterization of COX5A at COPaKB
This article incorporates text from the United States National Library of Medicine, which is in the public domain.
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