Seroatlas · Human Serome Atlas

FOXP3

Forkhead box protein P3

Also known as: AIID, DIETER, FOXP3_HUMAN, IPEX, JM2, PIDX, SCURFIN, XPID

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

Protein identityUniProt · HPA

UniProt accession
Q9BZS1
Gene
FOXP3
Ensembl
ENSG00000049768
Chromosome
X
Canonical length
431 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins, Transcription factors
Subcellular location
Nucleoplasm,Cytosol
Quaternary structure
Homodimer

OverviewNCBI Gene

The protein encoded by this gene is a member of the forkhead/winged-helix family of transcriptional regulators. Defects in this gene are the cause of immunodeficiency polyendocrinopathy, enteropathy, X-linked syndrome (IPEX), also known as X-linked autoimmunity-immunodeficiency syndrome. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

431 residues, UniProt reviewed canonical sequence.

>Q9BZS1|FOXP3
     1  MPNPRPGKPS APSLALGPSP GASPSWRAAP KASDLLGARG PGGTFQGRDL RGGAHASSSS
    61  LNPMPPSQLQ LPTLPLVMVA PSGARLGPLP HLQALLQDRP HFMHQLSTVD AHARTPVLQV
   121  HPLESPAMIS LTPPTTATGV FSLKARPGLP PGINVASLEW VSREPALLCT FPNPSAPRKD
   181  STLSAVPQSS YPLLANGVCK WPGCEKVFEE PEDFLKHCQA DHLLDEKGRA QCLLQREMVQ
   241  SLEQQLVLEK EKLSAMQAHL AGKMALTKAS SVASSDKGSC CIVAAGSQGP VVPAWSGPRE
   301  APDSLFAVRR HLWGSHGNST FPEFLHNMDY FKFHNMRPPF TYATLIRWAI LEAPEKQRTL
   361  NEIYHWFTRM FAFFRNHPAT WKNAIRHNLS LHKCFVRVES EKGAVWTVDE LEFRKKRSQR
   421  PSRCSNPTPG P

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FOXP3 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)
0.57
Highest tissue expression
6.6 nTPM

Expression across tissuesHPA

Tissue

  • appendix: 6.6 nTPM
  • thymus: 6.3 nTPM
  • lymph node: 5.3 nTPM
  • epididymis: 4.9 nTPM
  • tonsil: 4.7 nTPM
  • urinary bladder: 2.6 nTPM

Single-cell type

  • t-cells: 9.2 nCPM
  • epididymal principal cells: 4 nCPM
  • undifferentiated spermatogonia: 1.7 nCPM
  • early primary spermatocytes: 1.6 nCPM
  • thymic myoid cells: 1.4 nCPM
  • hepatocytes: 1.1 nCPM

Immune cell

  • T-reg: 52 nTPM
  • memory CD4 T-cell: 4.6 nTPM
  • total PBMC: 1.5 nTPM
  • naive CD4 T-cell: 0.9 nTPM
  • MAIT T-cell: 0.2 nTPM
  • memory CD8 T-cell: 0.2 nTPM

Brain region

  • cerebellum: 3.1 nTPM
  • amygdala: 2.3 nTPM
  • medulla oblongata: 2.2 nTPM
  • hippocampal formation: 2.1 nTPM
  • basal ganglia: 2 nTPM
  • cerebral cortex: 2 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about FOXP3.

Disease | AllUniProt

Conditions FOXP3 is implicated in, by any mechanism.

  • Immunodeficiency polyendocrinopathy, enteropathy, X-linked syndrome (IPEX) MIM:304790

Disease | GeneticClinVar

58 pathogenic / likely-pathogenic of 475 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Disease | ImmuneIEDB

Conditions an epitope on FOXP3 was assayed in.

ReferencesPubMed · IEDB

Publications for FOXP3 from three distinct lines of evidence, kept separate because they answer different questions: whether antibodies are directed at the protein, whether a B-cell epitope has been mapped on it, and whether a T-cell epitope has. Each is labelled with its source.

Reference: AutoantibodyPubMed

6 publications

Show 1 more

Reference: B cellIEDB

1 publication

Reference: T cellIEDB

1 publication

Sources: PubMed — antigen-level antibody evidence from a custom retrieval. Records matching a controlled set of autoantibody terms (the MeSH descriptors Autoantibodies and Autoantigens, with title and abstract term variants) were obtained through NCBI E-utilities, and their titles and abstracts parsed for constructions that direct an antibody at a named protein rather than for co-occurrence. Captured names were resolved against UniProt nomenclature and each antigen adjudicated individually against the source text. IEDB — curated epitope assays from the Immune Epitope Database (Vita et al., Nucleic Acids Research 2019). Bibliographic records from PubMed and MeSH, U.S. National Library of Medicine; citation metrics from NIH iCite (Hutchins et al., PLoS Biology 2016). Titles link to PubMed; abstracts are not reproduced here. The NLM does not endorse this analysis.

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)
0.2
gnomAD pLI
0.99
gnomAD missense Z
1.67
DepMap mean gene effect
0.04
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of FOXP3 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 FOXP3 as an antibody target. Whether an autoantibody or antibody against FOXP3 could matter depends on whether native FOXP3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FOXP3 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 FOXP3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/FOXP3. 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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