NDUFB3

NDUFB3 is a protein that in humans is encoded by the NDUFB3 gene. The protein encoded by this gene is an accessory subunit of the multisubunit NADH:ubiquinone oxidoreductase (complex I) that is located in the mitochondrial inner membrane. Complex I is the first enzyme of the mitochondrial electron transport chain.

Function

NDUFB3 is a subunit of the mitochondrial respiratory chain Complex I, a large enzyme complex that plays a central role in electron transport in mitochondria. The NDUFB3 subunit is one of about 31 proteins that make up Complex I. It is an accessory subunit, meaning it is not directly involved in the catalytic reaction of the complex, but is thought to have a structural role.

Structure

The NDUFB3 protein is a small protein of 103 amino acids with a molecular weight of about 12 kDa. It is located in the mitochondrial inner membrane, where it is tightly bound to the other subunits of Complex I. The exact structure of the NDUFB3 protein is not known, but it is thought to have a single transmembrane domain.

Clinical significance

Mutations in the NDUFB3 gene have been associated with mitochondrial complex I deficiency, a rare genetic disorder that can cause a wide range of clinical manifestations, including Leigh syndrome, a severe neurological disorder that usually becomes apparent in the first year of life.

See also

• Mitochondrial diseases
• Electron transport chain
• Mitochondrial complex I deficiency