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The N-terminus of mature human frataxin is intrinsically unfolded.

ABSTRACT: 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.

SUBMITTER: Prischi F

PROVIDER: S-EPMC3430858 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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The N-terminus of mature human frataxin is intrinsically unfolded.

Prischi Filippo F Giannini Clelia C Adinolfi Salvatore S Pastore Annalisa A

The FEBS journal 20091016 22

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 ...[more]

PMID: 19843162

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