Seroatlas · Human Serome Atlas

FOXO3

Forkhead box protein O3

Also known as: AF6q21, FKHRL1, FOXO2, FOXO3_HUMAN, FOXO3A

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

Protein identityUniProt · HPA

UniProt accession
O43524
Gene
FOXO3
Ensembl
ENSG00000118689
Chromosome
6
Canonical length
673 aa
Protein class
Cancer-related genes, Disease related genes, Predicted intracellular proteins, Transcription factors
Subcellular location
Nucleoplasm

OverviewNCBI Gene

This gene belongs to the forkhead family of transcription factors which are characterized by a distinct forkhead domain. This gene likely functions as a trigger for apoptosis through expression of genes necessary for cell death. Translocation of this gene with the MLL gene is associated with secondary acute leukemia. Alternatively spliced transcript variants encoding the same protein have been observed. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

673 residues, UniProt reviewed canonical sequence.

>O43524|FOXO3
     1  MAEAPASPAP LSPLEVELDP EFEPQSRPRS CTWPLQRPEL QASPAKPSGE TAADSMIPEE
    61  EDDEDDEDGG GRAGSAMAIG GGGGSGTLGS GLLLEDSARV LAPGGQDPGS GPATAAGGLS
   121  GGTQALLQPQ QPLPPPQPGA AGGSGQPRKC SSRRNAWGNL SYADLITRAI ESSPDKRLTL
   181  SQIYEWMVRC VPYFKDKGDS NSSAGWKNSI RHNLSLHSRF MRVQNEGTGK SSWWIINPDG
   241  GKSGKAPRRR AVSMDNSNKY TKSRGRAAKK KAALQTAPES ADDSPSQLSK WPGSPTSRSS
   301  DELDAWTDFR SRTNSNASTV SGRLSPIMAS TELDEVQDDD APLSPMLYSS SASLSPSVSK
   361  PCTVELPRLT DMAGTMNLND GLTENLMDDL LDNITLPPSQ PSPTGGLMQR SSSFPYTTKG
   421  SGLGSPTSSF NSTVFGPSSL NSLRQSPMQT IQENKPATFS SMSHYGNQTL QDLLTSDSLS
   481  HSDVMMTQSD PLMSQASTAV SAQNSRRNVM LRNDPMMSFA AQPNQGSLVN QNLLHHQHQT
   541  QGALGGSRAL SNSVSNMGLS ESSSLGSAKH QQQSPVSQSM QTLSDSLSGS SLYSTSANLP
   601  VMGHEKFPSD LDLDMFNGSL ECDMESIIRS ELMDADGLDF NFDSLISTQN VVGLNVGNFT
   661  GAKQASSQSW VPG

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FOXO3 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
Other membrane
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.67
Highest tissue expression
82 nTPM

Expression across tissuesHPA

Tissue

  • pancreas: 82 nTPM
  • skeletal muscle: 79 nTPM
  • bone marrow: 65 nTPM
  • tongue: 48 nTPM
  • adipose tissue: 44 nTPM
  • blood vessel: 42 nTPM

Single-cell type

  • neutrophils: 3,967 nCPM
  • monocytes: 1,186 nCPM
  • thymic myoid cells: 1,065 nCPM
  • neutrophil progenitors: 895 nCPM
  • myonuclei: 721 nCPM
  • epicardial cells: 666 nCPM

Immune cell

  • neutrophil: 16 nTPM
  • basophil: 7.8 nTPM
  • eosinophil: 6.1 nTPM
  • non-classical monocyte: 5.3 nTPM
  • MAIT T-cell: 3.8 nTPM
  • NK-cell: 3.7 nTPM

Brain region

  • cerebellum: 96 nTPM
  • choroid plexus: 67 nTPM
  • cerebral cortex: 67 nTPM
  • medulla oblongata: 64 nTPM
  • thalamus: 63 nTPM
  • white matter: 61 nTPM

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)
0.27
gnomAD pLI
0.99
gnomAD missense Z
1.68
DepMap mean gene effect
-0.35
DepMap dependency class
selective

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 FOXO3 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 FOXO3 as an antibody target. Whether an autoantibody or antibody against FOXO3 could matter depends on whether native FOXO3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FOXO3 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 FOXO3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/FOXO3. 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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