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101  structures 2324  species 0  interactions 2720  sequences 42  architectures

Family: Frataxin_Cyay (PF01491)

Summary: Frataxin-like domain

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This is the Wikipedia entry entitled "Frataxin-like domain". More...

Frataxin-like domain Edit Wikipedia article

Frataxin-like domain
PDB 1ekg EBI.jpg
mature human frataxin

In molecular biology, the frataxin-like domain is a protein domain found in proteins including eukaryotic frataxin and bacterial CyaY.

The bacterial CyaY proteins are iron-sulphur cluster (FeS) metabolism proteins which are homologous to eukaryotic frataxin. Partial phylogenetic profiling suggests that CyaY most likely functions as part of the ISC system for FeS cluster biosynthesis, and is supported by experimental data in some species.[1][2][3]


  1. ^ Haft DH, Paulsen IT, Ward N, Selengut JD (2006). "Exopolysaccharide-associated protein sorting in environmental organisms: the PEP-CTERM/EpsH system. Application of a novel phylogenetic profiling heuristic". BMC Biol. 4: 29. doi:10.1186/1741-7007-4-29. PMC 1569441. PMID 16930487.
  2. ^ Layer G, Ollagnier-de Choudens S, Sanakis Y, Fontecave M (June 2006). "Iron-sulfur cluster biosynthesis: characterization of Escherichia coli CYaY as an iron donor for the assembly of [2Fe-2S] clusters in the scaffold IscU". J. Biol. Chem. 281 (24): 16256–63. doi:10.1074/jbc.M513569200. PMID 16603772.
  3. ^ Vivas E, Skovran E, Downs DM (February 2006). "Salmonella enterica strains lacking the frataxin homolog CyaY show defects in Fe-S cluster metabolism in vivo". J. Bacteriol. 188 (3): 1175–9. doi:10.1128/JB.188.3.1175-1179.2006. PMC 1347345. PMID 16428423.
This article incorporates text from the public domain Pfam and InterPro: IPR002908

This page is based on a Wikipedia article. The text is available under the Creative Commons Attribution/Share-Alike License.

This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.

Frataxin-like domain Provide feedback

This family contains proteins that have a domain related to the globular C-terminus of Frataxin the protein that is mutated in Friedreich's ataxia. This domain is found in a family of bacterial proteins. The function of this domain is currently unknown. It has been suggested that this family is involved in iron transport.

Literature references

  1. Gibson TJ, Koonin EV, Musco G, Pastore A, Bork P; , Trends Neurosci 1996;19:465-468.: Friedreich's ataxia protein: phylogenetic evidence for mitochondrial dysfunction. PUBMED:8931268 EPMC:8931268

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR002908

The eukaryotic proteins in this entry include frataxin, the protein that is mutated in Friedreich's ataxia [ PUBMED:8931268 ], and related sequences. Friedreich's ataxia is a progressive neurodegenerative disorder caused by loss of function mutations in the gene encoding frataxin (FRDA). Frataxin mRNA is predominantly expressed in tissues with a high metabolic rate (including liver, kidney, brown fat and heart). Mouse and yeast frataxin homologues contain a potential N-terminal mitochondrial targeting sequence, and human frataxin has been observed to co-localise with a mitochondrial protein. Furthermore, disruption of the yeast gene has been shown to result in mitochondrial dysfunction. Friedreich's ataxia is thus believed to be a mitochondrial disease caused by a mutation in the nuclear genome (specifically, expansion of an intronic GAA triplet repeat) [ PUBMED:8596916 , PUBMED:8815938 , PUBMED:9241270 ].

The bacterial proteins in this entry are iron-sulphur cluster (FeS) metabolism CyaY proteins homologous to eukaryotic frataxin. Partial Phylogenetic Profiling [ PUBMED:16930487 ] suggests that CyaY most likely functions as part of the ISC system for FeS cluster biosynthesis, and is supported by expermimental data in some species [ PUBMED:16603772 , PUBMED:16428423 ].

Gene Ontology

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Domain organisation

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You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.

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Curation and family details

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Seed source: Gibson TJ
Previous IDs: none
Type: Domain
Sequence Ontology: SO:0000417
Author: Gibson TJ , Bateman A
Number in seed: 227
Number in full: 2720
Average length of the domain: 106.00 aa
Average identity of full alignment: 32 %
Average coverage of the sequence by the domain: 64.50 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 61295632 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 21.3 21.3
Trusted cut-off 22.0 21.6
Noise cut-off 21.2 21.1
Model length: 109
Family (HMM) version: 19
Download: download the raw HMM for this family

Species distribution

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Colour assignments

Archea Archea Eukaryota Eukaryota
Bacteria Bacteria Other sequences Other sequences
Viruses Viruses Unclassified Unclassified
Viroids Viroids Unclassified sequence Unclassified sequence


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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Frataxin_Cyay domain has been found. There are 101 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.

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