Promotes the biosynthesis of heme and assembly and repair of iron-sulfur clusters by delivering Fe(2+) to proteins involved in these pathways. May play a role in the protection against iron-catalyzed oxidative stress through its ability to catalyze the oxidation of Fe(2+) to Fe(3+); the oligomeric form but not the monomeric form has in vitro ferroxidase activity. May be able to store large amounts of iron in the form of a ferrihydrite mineral by oligomerization; however, the physiological relevance is unsure as reports are conflicting and the function has only been shown using heterologous overexpression systems. Modulates the RNA-binding activity of ACO1. Defects in FXN are the cause of Friedreich ataxia (FRDA). FRDA is an autosomal recessive, progressive degenerative disease characterized by neurodegeneration and cardiomyopathy it is the most common inherited ataxia. The disorder is usually manifest before adolescence and is generally characterized by incoordination of limb movements, dysarthria, nystagmus, diminished or absent tendon reflexes, Babinski sign, impairment of position and vibratory senses, scoliosis, pes cavus, and hammer toe. In most patients, FRDA is due to GAA triplet repeat expansions in the first intron of the frataxin gene. But in some cases the disease is due to mutations in the coding region. Belongs to the frataxin family. 2 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.
Protein type: Mitochondrial; EC 22.214.171.124; Motility/polarity/chemotaxis
Molecular Function: 2 iron, 2 sulfur cluster binding; ferroxidase activity; protein binding; ferric iron binding; ferrous iron binding; iron-sulfur cluster binding
Biological Process: mitochondrion organization and biogenesis; negative regulation of multicellular organism growth; cellular iron ion homeostasis; positive regulation of transferase activity; positive regulation of metalloenzyme activity; proprioception; negative regulation of organ growth; positive regulation of cell growth; adult walking behavior; embryonic development ending in birth or egg hatching; protein autoprocessing; iron incorporation into metallo-sulfur cluster; positive regulation of lyase activity; positive regulation of cell proliferation; aerobic respiration; ion transport; response to iron ion; oxidative phosphorylation; heme biosynthetic process; positive regulation of oxidoreductase activity; negative regulation of apoptosis
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.