NDUFA3: NADH:Ubiquinone Oxidoreductase Subunit A3
Mitochondrial Complex I Subunit Involved in Oxidative Phosphorylation
Gene Information Card
| Symbol | NDUFA3 |
|---|---|
| Full Name | NADH:Ubiquinone Oxidoreductase Subunit A3 |
| Gene Type | Protein coding |
| Chromosomal Location | 19q13.42 |
| NCBI Gene ID | 4696 ncbi.nlm.nih.gov/gene/4696 |
| Ensembl ID | ENSG00000105675 |
| UniProt ID | O95167 |
| OMIM ID | 603834 |
| HGNC ID | 7686 |
| Aliases | CI-B9, B9, NADH-ubiquinone oxidoreductase B9 subunit |
Description
The NDUFA3 gene encodes a 9 kDa subunit (B9) of mitochondrial complex I (NADH:ubiquinone oxidoreductase), the first enzyme of the electron transport chain. This nuclear-encoded accessory subunit is essential for complex I assembly and stability. Mutations in NDUFA3 are associated with mitochondrial complex I deficiency, leading to Leigh syndrome and other early-onset neurological disorders.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Mitochondrial complex I deficiency, nuclear type 1 | Loss-of-function mutations impair complex I assembly and activity, reducing ATP production and increasing oxidative stress. | ClinVar, OMIM |
| Leigh syndrome | Biallelic pathogenic variants in NDUFA3 disrupt mitochondrial respiration, causing neurodegeneration. | ClinVar, OMIM |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Heart | 12.5 | High |
| Skeletal muscle | 10.8 | High |
| Liver | 8.2 | Medium |
| Brain | 7.9 | Medium |
| Kidney | 6.4 | Medium |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | 15.2 | High expression |
| HeLa | 11.3 | High expression |
| SH-SY5Y | 9.8 | Medium expression |
| HepG2 | 7.5 | Medium expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1A>G (p.Met1?) | Missense | Rare | Loss of start codon, likely loss of function |
| c.206C>T (p.Thr69Ile) | Missense | Rare | Reduced complex I activity |
| c.340G>A (p.Gly114Arg) | Missense | Rare | Impaired assembly |
Mutation functional classification
Loss of Function (LOF)
Pathogenic missense and start-loss variants reduce or abolish NDUFA3 function, leading to complex I deficiency.
Gain of Function (GOF)
No gain-of-function mutations reported.
Dominant Negative (DN)
No dominant-negative mutations reported.
View complete mutation data：
Gene Ontology (GO)
| • NADH dehydrogenase (ubiquinone) activity | • mitochondrial respiratory chain complex I assembly |
| • mitochondrial inner membrane | • oxidation-reduction process |
Pathways
• Oxidative phosphorylation (KEGG: hsa00190)
• Respiratory electron transport (Reactome: R-HSA-611105)
Protein Summary
NDUFA3 is a 9.3 kDa protein (84 amino acids) localized to the mitochondrial inner membrane as part of complex I. It contains a transmembrane domain and is required for the assembly of the peripheral arm of complex I. The protein interacts with other subunits to facilitate electron transfer from NADH to ubiquinone.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| NDUFA3 Knockout HEK293 Cell Line | EDJ-KQ5311 | Human | 4696 | Details Get a Quote |
| NDUFA3 Knockout HeLa Cell Line | EDJ-KQ27150 | Human | 4696 | Details Get a Quote |
| NDUFA3 Knockout A-549 Cell Line | EDJ-KQ28377 | Human | 4696 | Details Get a Quote |
| NDUFA3 Knockout HCT 116 Cell Line | EDJ-KQ28378 | Human | 4696 | Details Get a Quote |
