Mitochondrially encoded NADH:ubiquinone oxidoreductase core subunit 4L (MT-ND4L)

Mitochondrially encoded NADH:ubiquinone oxidoreductase core subunit 4L (MT-ND4L) is a protein subunit of mitochondrial respiratory chain Complex I, localized in the inner mitochondrial membrane. It is encoded by the mitochondrial genome and forms part of the highly hydrophobic transmembrane core of the Complex I enzyme. MT-ND4L participates in the initial step of the electron transport chain, transferring electrons from NADH to ubiquinone (coenzyme Q10), a process that drives proton translocation and ATP synthesis via oxidative phosphorylation. Mutations in MT-ND4L are pathogenic and cause mitochondrial disorders such as Leber hereditary optic neuropathy and have been linked to metabolic diseases. No drugs are known to specifically target MT-ND4L, but the full complex is sensitive to certain inhibitors and toxins. Dysfunction of this subunit critically impairs mitochondrial bioenergetic capacity, with systemic disease implications.

Other names

NADH-ubiquinone oxidoreductase chain 4LMTND4LNADH dehydrogenase subunit 4LNADH dehydrogenase 4LComplex I, subunit ND4LNADH4LND4LNAD4LNADH-ubiquinone oxidoreductase, subunit ND4L

Inhibitors of mitochondrial complex I (for the enzyme complex as a whole, not specifically MT-ND4L subunit) lead to disruption of electron transport from NADH to ubiquinone, impairing ATP synthesis (typical for pathogenic mutations; no approved drugs act specifically on MT-ND4L).