Frataxin

• OMIM: 606 859
• UniProt: Q16595

Frataxin (gene name: FXN ) is a small protein, localized in the mitochondria of eukaryotes. It is known that frataxin plays a crucial role in the formation of iron- sulfur proteins and and the mitochondrial iron transport. Mutations in the FXN gene can cause hereditary frataxin deficiency.

Occurrence

Frataxin is found at the inner mitochondrial membrane, especially in the cerebellum, in the motor neurons, pancreatic cells, and cells of the heart muscle.

In humans, genetic defects known for frataxin (GAA trinucleotide repeat expansion ), which lead to various diseases ( Friedreich's ataxia). Decreased Frataxinbildung can lead to a high concentration of iron in the mitochondria of cells, which promotes the formation of toxic free radicals. The iron concentrations in the cytoplasm are then lowered simultaneously. Impaired Frataxinbildung leads to disruption of the mitochondrial energy metabolism.

Known diseases are due to a disturbance of the Frataxinbildung

• Friedreich's Ataxia: Friedreich 's ataxia is an autosomal recessive disorder.
• The frataxin -related cardiomyopathy: myocardial siderosis in Friedreich ataxia. Iron accumulates in the mitochondria of the heart muscle (myocardium ), and effects a change in the energy metabolism.
• Type 2 diabetes mellitus (known as adult-onset diabetes ). A frataxin deficiency in pancreatic cells appear to have a link with the emergence of adult-onset diabetes.