Seroatlas · Human Serome Atlas

FXN

Frataxin, mitochondrial

Also known as: CyaY, FA, FARR, FRDA, FRDA_HUMAN, X25

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
Q16595
Gene
FXN
Ensembl
ENSG00000165060
Chromosome
9
Canonical length
210 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Potential drug targets, Predicted intracellular proteins, Transporters
Subcellular location
Mitochondria,Cytosol
Quaternary structure
Homodimer

OverviewNCBI Gene

This nuclear gene encodes a mitochondrial protein which belongs to the FRATAXIN family. The protein functions in regulating mitochondrial iron transport and respiration. The expansion of intronic trinucleotide repeat GAA from 8-33 repeats to >90 repeats results in Friedreich ataxia. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2016]

Canonical amino-acid sequenceUniProt

210 residues, UniProt reviewed canonical sequence.

>Q16595|FXN
     1  MWTLGRRAVA GLLASPSPAQ AQTLTRVPRP AELAPLCGRR GLRTDIDATC TPRRASSNQR
    61  GLNQIWNVKK QSVYLMNLRK SGTLGHPGSL DETTYERLAE ETLDSLAEFF EDLADKPYTF
   121  EDYDVSFGSG VLTVKLGGDL GTYVINKQTP NKQIWLSSPS SGPKRYDWTG KNWVYSHDGV
   181  SLHELLAAEL TKALKTKLDL SSLAYSGKDA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FXN can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.47
Highest tissue expression
43 nTPM

Expression across tissuesHPA

Tissue

  • liver: 43 nTPM
  • bone marrow: 27 nTPM
  • skeletal muscle: 24 nTPM
  • heart muscle: 24 nTPM
  • parathyroid gland: 21 nTPM
  • tongue: 19 nTPM

Single-cell type

  • oocytes: 14 nCPM
  • parietal cells: 11 nCPM
  • hepatocytes: 10 nCPM
  • erythrocyte progenitors: 7.9 nCPM
  • megakaryocytes: 6.2 nCPM
  • megakaryocyte progenitors: 4.7 nCPM

Immune cell

  • naive CD4 T-cell: 62 nTPM
  • NK-cell: 61 nTPM
  • naive CD8 T-cell: 60 nTPM
  • total PBMC: 49 nTPM
  • gdT-cell: 49 nTPM
  • memory CD8 T-cell: 48 nTPM

Brain region

  • choroid plexus: 18 nTPM
  • white matter: 15 nTPM
  • hypothalamus: 15 nTPM
  • midbrain: 15 nTPM
  • medulla oblongata: 14 nTPM
  • pons: 14 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about FXN.

Disease | AllUniProt

Conditions FXN is implicated in, by any mechanism.

Disease | GeneticClinVar

26 pathogenic / likely-pathogenic of 145 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
0.72
gnomAD pLI
0.34
gnomAD missense Z
0.28
DepMap mean gene effect
-0.63
DepMap dependency class
common

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

  • Frataxin/CyaY
  • Frataxin
  • Frataxin conserved site
  • Frataxin/CyaY superfamily
  • Frataxin-like domain

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of FXN in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads FXN as an antibody target. Whether an autoantibody or antibody against FXN could matter depends on whether native FXN is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FXN is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label FXN as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/FXN. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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