NDUFB1

NDUFB1
Identifiers
Aliases	NDUFB1, CI-MNLL, CI-SGDH, MNLL, NADH:ubiquinone oxidoreductase subunit B1
External IDs	OMIM: 603837; GeneCards: NDUFB1
Gene location (Human) Chr. Chromosome 14 (human)[1] Band 14q32.12 Start 92,116,122 bp[1] End 92,121,917 bp[1]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in left ventricle apex of heart right auricle of heart right ventricle renal medulla anterior pituitary endothelial cell left adrenal cortex mucosa of transverse colon body of tongue n/a More reference expression data BioGPS More reference expression data
Gene ontology Molecular function NADH dehydrogenase (ubiquinone) activity NADH dehydrogenase activity Cellular component integral component of membrane mitochondrial inner membrane mitochondrial respiratory chain complex I respirasome membrane mitochondrion nuclear speck Biological process mitochondrial electron transport, NADH to ubiquinone mitochondrial respiratory chain complex I assembly Sources:Amigo / QuickGO
Orthologs Databases NCBI: entry; OMA: entry Species Human Mouse Entrez 4707 102631912 Ensembl ENSG00000183648 n/a UniProt O75438 n/a RefSeq (mRNA) NM_004545 n/a RefSeq (protein) NP_004536 n/a Location (UCSC) Chr 14: 92.12 – 92.12 Mb n/a PubMed search [2] [3]
Wikidata
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NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 1 is an enzyme that in humans is encoded by the NDUFB1 gene.^[4][5] NADH dehydrogenase (ubiquinone) 1 beta subcomplex, 1, 7kDa 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.^[6]

Structure

The NDUFB1 gene, located on the q arm of chromosome 14 in position 32.12, is 5,687 base pairs long. The NDUFB1 protein weighs 7 kDa and is composed of 58 amino acids.^[7][8] NDUFB1 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.^[6] NDUFB1 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.^[5]

Function

The human NDUFB1 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone.^[5] However, NDUFB1 is an accessory subunit of the complex that is believed not to be involved in catalysis.^[9] 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.^[6]

References

Further reading

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