NDUFB2

NDUFB2
Identifiers
Aliases	NDUFB2 , AGGG, CI-AGGG, NADH:ubiquinone oxidoreductase subunit B2
External IDs	OMIM: 603838 MGI: 1915448 HomoloGene: 3341 GeneCards: NDUFB2
Gene location (Human) Chr. Chromosome 7 (human) [1] Band 7q34 Start 140,690,777 bp [1] End 140,722,790 bp [1]
Gene location (Mouse) Chr. Chromosome 6 (mouse) [2] Band 6|6 B1 Start 39,569,508 bp [2] End 39,580,316 bp [2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in right ventricle right lobe of thyroid gland kidney tubule prefrontal cortex left lobe of thyroid gland metanephric glomerulus endothelial cell nucleus accumbens thoracic diaphragm putamen Top expressed in interventricular septum plantaris muscle extraocular muscle facial motor nucleus extensor digitorum longus muscle myocardium of ventricle digastric muscle soleus muscle intercostal muscle thoracic diaphragm More reference expression data BioGPS More reference expression data
Gene ontology Molecular function NADH dehydrogenase (ubiquinone) activity Cellular component mitochondrial inner membrane mitochondrial respiratory chain complex I respirasome membrane mitochondrion Biological process mitochondrial electron transport, NADH to ubiquinone mitochondrial respiratory chain complex I assembly Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 4708 68198 Ensembl ENSG00000090266 ENSMUSG00000002416 UniProt O95178 Q9CPU2 RefSeq (mRNA) NM_004546 NM_026612 NM_001358797 RefSeq (protein) NP_004537 NP_080888 NP_001345726 Location (UCSC) Chr 7: 140.69 – 140.72 Mb Chr 6: 39.57 – 39.58 Mb PubMed search [3] [4]
Wikidata
View/Edit Human View/Edit Mouse

NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 2, mitochondrial is an enzyme that in humans is encoded by the NDUFB2 gene. ^{[5] [6] [7]} NADH dehydrogenase (ubiquinone) 1 beta subcomplex, 2, 8kDa is an accessory subunit of the NADH dehydrogenase (ubiquinone) complex, located in the mitochondrial inner membrane. It is also known as Complex I and is the largest of the five complexes of the electron transport chain. ^[8]

Structure

The NDUFB2 gene, located on the q arm of chromosome 7 in position 34, is 9,966 base pairs long and is composed of 4 exons. ^[7] The NDUFB2 protein weighs 12 kDa and is composed of 105 amino acids. ^{[9] [10]} NDUFB2 is a subunit of the enzyme NADH dehydrogenase (ubiquinone), the largest of the respiratory complexes. The structure is L-shaped with a long, hydrophobic transmembrane domain and a hydrophilic domain for the peripheral arm that includes all the known redox centers and the NADH binding site. ^[8] NDUFB3 is one of about 31 hydrophobic subunits that form the transmembrane region of Complex I. It has been noted that the N-terminal hydrophobic domain has the potential to be folded into an alpha helix spanning the inner mitochondrial membrane with a C-terminal hydrophilic domain interacting with globular subunits of Complex I. The highly conserved two-domain structure suggests that this feature is critical for the protein function and that the hydrophobic domain acts as an anchor for the NADH dehydrogenase (ubiquinone) complex at the inner mitochondrial membrane. Hydropathy analysis revealed that this subunit and 4 other subunits have an overall hydrophilic pattern, even though they are found within the hydrophobic protein (HP) fraction of complex I. ^[7]

Function

The human NDUFB2 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. ^[7] However, NDUFB2 is an accessory subunit of the complex that is believed not to be involved in catalysis. ^[11] Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH₂. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH₂). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix. ^[8]

References

1. GRCh38: Ensembl release 89: ENSG00000090266 - Ensembl, May 2017
2. GRCm38: Ensembl release 89: ENSMUSG00000002416 - Ensembl, May 2017
3. "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
4. "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
5. Emahazion T, Beskow A, Gyllensten U, Brookes AJ (Nov 1998). "Intron based radiation hybrid mapping of 15 complex I genes of the human electron transport chain". Cytogenet Cell Genet. 82 (1–2): 115–9. doi:10.1159/000015082. PMID   9763677. S2CID   46818955.
6. Loeffen JL, Triepels RH, van den Heuvel LP, Schuelke M, Buskens CA, Smeets RJ, Trijbels JM, Smeitink JA (Jan 1999). "cDNA of eight nuclear encoded subunits of NADH:ubiquinone oxidoreductase: human complex I cDNA characterization completed". Biochem Biophys Res Commun. 253 (2): 415–22. doi:10.1006/bbrc.1998.9786. PMID   9878551.
7. "Entrez Gene: NDUFB2 NADH dehydrogenase (ubiquinone) 1 beta subcomplex, 2, 8kDa".
8. Voet D, Voet JG, Pratt CW (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.
9. 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 (Oct 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.
10. "NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 1". Cardiac Organellar Protein Atlas Knowledgebase (COPaKB).
11. "NDUFB2 - NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 2". UniProt: a hub for protein information. The UniProt Consortium. Retrieved 2 April 2015.

Further reading

• Gerhard DS, Wagner L, Feingold EA, et al. (2004). "The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)". Genome Res. 14 (10B): 2121–7. doi:10.1101/gr.2596504. PMC   528928 . PMID   15489334.
• Yeh CH, Pang JH, Wu YC, et al. (2004). "Differential-display polymerase chain reaction identifies nicotinamide adenine dinucleotide-ubiquinone oxidoreductase as an ischemia/reperfusion-regulated gene in cardiomyocytes". Chest. 125 (1): 228–35. doi:10.1378/chest.125.1.228. PMID   14718445.
• Scherer SW, Cheung J, MacDonald JR, et al. (2003). "Human chromosome 7: DNA sequence and biology". Science. 300 (5620): 767–72. Bibcode:2003Sci...300..767S. doi:10.1126/science.1083423. PMC   2882961 . PMID   12690205.
• Strausberg RL, Feingold EA, Grouse LH, et al. (2003). "Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences". Proc. Natl. Acad. Sci. U.S.A. 99 (26): 16899–903. Bibcode:2002PNAS...9916899M. doi: 10.1073/pnas.242603899 . PMC   139241 . PMID   12477932.
• Zhang QH, Ye M, Wu XY, et al. (2001). "Cloning and functional analysis of cDNAs with open reading frames for 300 previously undefined genes expressed in CD34+ hematopoietic stem/progenitor cells". Genome Res. 10 (10): 1546–60. doi:10.1101/gr.140200. PMC   310934 . PMID   11042152.
• Sanger Centre, The; Washington University Genome Sequencing Cente, The (1999). "Toward a complete human genome sequence". Genome Res. 8 (11): 1097–108. doi: 10.1101/gr.8.11.1097 . PMID   9847074.

This article incorporates text from the United States National Library of Medicine, which is in the public domain.