The N‐terminus of mature human frataxin is intrinsically unfolded

<jats:p>Frataxin is a highly conserved nuclear‐encoded mitochondrial protein whose deficiency is the primary cause of Friedreich’s ataxia, an autosomal recessive neurodegenerative disease. The frataxin structure comprises a well‐characterized globular domain that is present in all species and is preceded in eukaryotes by a non‐conserved N‐terminal tail that contains the mitochondrial import signal. Little is known about the structure and dynamic properties of the N‐terminal tail. Here, we show that this region is flexible and intrinsically unfolded in human frataxin. It does not alter the iron‐binding or self‐aggregation properties of the globular domain. It is therefore very unlikely that this region could be important for the conserved functions of the protein.</jats:p>