NDUFB2

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title: "NDUFB2" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["human-proteins"] description: "Protein-coding gene in the species Homo sapiens" topic_path: "general/human-proteins" source: "https://en.wikipedia.org/wiki/NDUFB2" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Protein-coding gene in the species Homo sapiens ::

NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 2, mitochondrial is an enzyme that in humans is encoded by the NDUFB2 gene. 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.

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. The NDUFB2 protein weighs 12 kDa and is composed of 105 amino acids. 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. 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.

Function

The human NDUFB2 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. However, NDUFB2 is an accessory subunit of the complex that is believed not to be involved in catalysis. 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.

References

References

1. (Nov 1998). "Intron based radiation hybrid mapping of 15 complex I genes of the human electron transport chain". Cytogenet Cell Genet.
2. (Jan 1999). "cDNA of eight nuclear encoded subunits of NADH:ubiquinone oxidoreductase: human complex I cDNA characterization completed". Biochem Biophys Res Commun.
3. "Entrez Gene: NDUFB2 NADH dehydrogenase (ubiquinone) 1 beta subcomplex, 2, 8kDa".
4. (2013). "Fundamentals of biochemistry: life at the molecular level". Wiley.
5. (Oct 2013). "Integration of cardiac proteome biology and medicine by a specialized knowledgebase". Circulation Research.
6. "NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 1". Cardiac Organellar Protein Atlas Knowledgebase (COPaKB).
7. "NDUFB2 - NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 2". The UniProt Consortium.

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::