| NDUFA4 | |
|---|---|
| Full Name | NADH:Ubiquinone Oxidoreductase Subunit A4 |
| Symbol | NDUFA4 |
| Chromosomal Location | 12p13.33 |
| NCBI Gene ID | [4716](https://www.ncbi.nlm.nih.gov/gene/4716) |
| OMIM | [602335](https://www.omim.org/entry/602335) |
| Ensembl ID | [ENSG00000189090](https://ensembl.org/Homo_species/Gene/Summary?g=ENSG00000189090) |
| UniProt ID | [O00483](https://www.uniprot.org/uniprot/O00483) |
| Associated Diseases | [Leigh Syndrome](/diseases/leigh-syndrome), [Mitochondrial Complex I Deficiency](/diseases/mitochondrial-complex-i-deficiency), [Alzheimer's Disease](/diseases/alzheimers-disease) |
NDUFA4 (NADH:Ubiquinone Oxidoreductase Subunit A4) encodes a core subunit of mitochondrial Complex I (NADH:ubiquinone oxidoreductase), the largest enzyme of the mitochondrial electron transport chain. Complex I catalyzes the oxidation of NADH and the transfer of electrons to ubiquinone, driving proton pumping across the inner mitochondrial membrane to generate the electrochemical gradient for ATP synthesis.
Originally annotated as a Complex I subunit, NDUFA4 was reclassified in 2013 as a subunit of cytochrome c oxidase (Complex IV)[1]. Current evidence suggests it may function in both complexes, though this remains controversial.
NDUFA4 participates in:
NDUFA4 mutations cause a severe form of mitochondrial disease characterized by progressive loss of motor and cognitive function, bilateral lesions in the brainstem and basal ganglia, and typically early childhood death[2].
NDUFA4 variants impair mitochondrial respiration, leading to lactic acidosis, encephalopathy, and multi-system involvement including cardiomyopathy and hepatopathy.
Reduced NDUFA4 expression has been reported in AD brains, contributing to mitochondrial dysfunction and impaired energy metabolism in neurons[3].
| Brain Region | Expression Level |
|---|---|
| Cerebral Cortex | High |
| Hippocampus | High |
| Cerebellum | Moderate |
| Basal Ganglia | Moderate |
| Brainstem | Low-Moderate |
| Variant | Type | Function | Associated Phenotype |
|---|---|---|---|
| p.R75Q | Missense | Partial loss | Milder phenotype |
| p.L71P | Missense | Severe loss | Leigh syndrome |
| c.224delC | Frameshift | Null | Early onset |
AAV-mediated NDUFA4 delivery is under investigation for mitochondrial disease treatment.