COX4I2

Cytochrome c oxidase subunit IV isoform 2 (lung)
Identifiers
Symbols	COX4I2 ; COX4; COX4-2; COX4B; COX4L2; COXIV-2; dJ857M17.2
External IDs	OMIM: 607976 MGI: 2135755 HomoloGene: 13082 GeneCards: COX4I2 Gene
Gene ontology Molecular function • cytochrome-c oxidase activity Cellular component • mitochondrial respiratory chain complex IV Biological process • generation of precursor metabolites and energy • mitochondrial electron transport, cytochrome c to oxygen • aerobic respiration • cellular respiration • oxidation-reduction process • hydrogen ion transmembrane transport Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	84701	84682
Ensembl	ENSG00000131055	ENSMUSG00000009876
UniProt	Q96KJ9	Q91W29
RefSeq (mRNA)	NM_032609	NM_053091
RefSeq (protein)	NP_115998	NP_444321
Location (UCSC)	Chr 20: 31.64 – 31.65 Mb	Chr 2: 152.75 – 152.77 Mb
PubMed search

Cytochrome c oxidase subunit 4 isoform 2, mitochondrial is an enzyme that in humans is encoded by the COX4I2 gene.^[1][2][3]

Function

Cytochrome c oxidase (COX), the terminal enzyme of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. It is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may be involved in the regulation and assembly of the complex. This nuclear gene encodes isoform 2 of subunit IV. Isoform 1 of subunit IV is encoded by a different gene, however, the two genes show a similar structural organization. Subunit IV is the largest nuclear encoded subunit which plays a pivotal role in COX regulation.^[3]

Interactions

COX4I2 has been shown to interact with Cytochrome c.^[4][5][6][7]

References

1. Hüttemann M, Kadenbach B, Grossman LI (Apr 2001). "Mammalian subunit IV isoforms of cytochrome c oxidase". Gene 267 (1): 111–23. doi:10.1016/S0378-1119(01)00385-7. PMID 11311561.
2. Hüttemann M, Lee I, Liu J, Grossman LI (Nov 2007). "Transcription of mammalian cytochrome c oxidase subunit IV-2 is controlled by a novel conserved oxygen responsive element". The FEBS Journal 274 (21): 5737–48. doi:10.1111/j.1742-4658.2007.06093.x. PMID 17937768.
3. "Entrez Gene: COX4I2 cytochrome c oxidase subunit IV isoform 2 (lung)".
4. Michel B, Bosshard HR (Aug 1984). "Spectroscopic analysis of the interaction between cytochrome c and cytochrome c oxidase". The Journal of Biological Chemistry 259 (16): 10085–91. PMID 6088481.
5. Wiedemann FR, Vielhaber S, Schröder R, Elger CE, Kunz WS (Mar 2000). "Evaluation of methods for the determination of mitochondrial respiratory chain enzyme activities in human skeletal muscle samples". Analytical Biochemistry 279 (1): 55–60. doi:10.1006/abio.1999.4434. PMID 10683230.
6. Sampson V, Alleyne T (Dec 2001). "Cytochrome c/cytochrome c oxidase interaction. Direct structural evidence for conformational changes during enzyme turnover". European Journal of Biochemistry / FEBS 268 (24): 6534–44. doi:10.1046/j.0014-2956.2001.02608.x. PMID 11737208.
7. Lynch SR, Sherman D, Copeland RA (Jan 1992). "Cytochrome c binding affects the conformation of cytochrome a in cytochrome c oxidase". The Journal of Biological Chemistry 267 (1): 298–302. PMID 1309738.

Further reading

• Lynch SR, Sherman D, Copeland RA (Jan 1992). "Cytochrome c binding affects the conformation of cytochrome a in cytochrome c oxidase". The Journal of Biological Chemistry 267 (1): 298–302. PMID 1309738.
• Garber EA, Margoliash E (Feb 1990). "Interaction of cytochrome c with cytochrome c oxidase: an understanding of the high- to low-affinity transition". Biochimica et Biophysica Acta 1015 (2): 279–87. doi:10.1016/0005-2728(90)90032-Y. PMID 2153405.
• Bolli R, Nałecz KA, Azzi A (Jan 1985). "The interconversion between monomeric and dimeric bovine heart cytochrome c oxidase". Biochimie 67 (1): 119–28. doi:10.1016/S0300-9084(85)80237-6. PMID 2986725.
• Michel B, Bosshard HR (Aug 1984). "Spectroscopic analysis of the interaction between cytochrome c and cytochrome c oxidase". The Journal of Biological Chemistry 259 (16): 10085–91. PMID 6088481.
• Hare JF, Ching E, Attardi G (May 1980). "Isolation, subunit composition, and site of synthesis of human cytochrome c oxidase". Biochemistry 19 (10): 2023–30. doi:10.1021/bi00551a003. PMID 6246917.
• Papadopoulou LC, Tsiftsoglou AS (Sep 1996). "Effects of hemin on apoptosis, suppression of cytochrome c oxidase gene expression, and bone-marrow toxicity induced by doxorubicin (adriamycin)". Biochemical Pharmacology 52 (5): 713–22. doi:10.1016/0006-2952(96)00349-8. PMID 8765469.
• Wiedemann FR, Vielhaber S, Schröder R, Elger CE, Kunz WS (Mar 2000). "Evaluation of methods for the determination of mitochondrial respiratory chain enzyme activities in human skeletal muscle samples". Analytical Biochemistry 279 (1): 55–60. doi:10.1006/abio.1999.4434. PMID 10683230.
• Sampson V, Alleyne T (Dec 2001). "Cytochrome c/cytochrome c oxidase interaction. Direct structural evidence for conformational changes during enzyme turnover". European Journal of Biochemistry / FEBS 268 (24): 6534–44. doi:10.1046/j.0014-2956.2001.02608.x. PMID 11737208.
• Vizirianakis IS, Pappas IS, Tsiftsoglou AS (Mar 2002). "Differentiation-dependent repression of c-myc, B22, COX II and COX IV genes in murine erythroleukemia (MEL) cells". Biochemical Pharmacology 63 (5): 1009–17. doi:10.1016/S0006-2952(01)00937-6. PMID 11911854.
• Fukuda R, Zhang H, Kim JW, Shimoda L, Dang CV, Semenza GL (Apr 2007). "HIF-1 regulates cytochrome oxidase subunits to optimize efficiency of respiration in hypoxic cells". Cell 129 (1): 111–22. doi:10.1016/j.cell.2007.01.047. PMID 17418790.