NADH dehydrogenase [ubiquinone] 1 alpha subcomplex subunit 13

NDUFA13 encodes a 144-amino-acid accessory subunit of mitochondrial Complex I (NADH dehydrogenase), the entry point of the electron transport chain. Although not directly catalytic, this subunit is essential for Complex I assembly and function in oxidative phosphorylation (UniProt: Q9P0J0). The protein also participates in interferon/retinoic acid-induced apoptosis and may modulate innate immune responses in intestinal epithelial cells.

Mutations in NDUFA13 cause mitochondrial complex I deficiency, nuclear type 28 (MC1DN28), an autosomal recessive condition presenting with variable neurological manifestations including progressive leukodystrophy, encephalopathy, Leigh syndrome, and neurodegenerative phenotypes (UniProt: Q9P0J0). The protein is also implicated in Hurthle cell thyroid carcinoma.

In Alzheimer's disease, NDUFA13 is significantly downregulated in post-mortem AD brain tissue relative to age-matched controls (mean log2 fold-change: −0.49) (Chaparral AD proteomics). This reduction suggests impaired Complex I assembly or stability in AD, potentially contributing to the mitochondrial dysfunction and bioenergetic stress characteristic of neurodegenerative pathology.