Seroatlas · Human Serome Atlas

XAF1

XIAP-associated factor 1

Also known as: BIRC4BP, HSXIAPAF1, XAF1_HUMAN, XIAPAF1

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

Protein identityUniProt · HPA

UniProt accession
Q6GPH4
Gene
XAF1
Ensembl
ENSG00000132530
Chromosome
17
Canonical length
301 aa
Protein class
Predicted intracellular proteins
Subcellular location
Nucleoplasm,Mitochondria

OverviewNCBI Gene

This gene encodes a protein which binds to and counteracts the inhibitory effect of a member of the IAP (inhibitor of apoptosis) protein family. IAP proteins bind to and inhibit caspases which are activated during apoptosis. The proportion of IAPs and proteins which interfere with their activity, such as the encoded protein, affect the progress of the apoptosis signaling pathway. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Feb 2012]

Canonical amino-acid sequenceUniProt

301 residues, UniProt reviewed canonical sequence.

>Q6GPH4|XAF1
     1  MEGDFSVCRN CKRHVVSANF TLHEAYCLRF LVLCPECEEP VPKETMEEHC KLEHQQVGCT
    61  MCQQSMQKSS LEFHKANECQ ERPVECKFCK LDMQLSKLEL HESYCGSRTE LCQGCGQFIM
   121  HRMLAQHRDV CRSEQAQLGK GERISAPERE IYCHYCNQMI PENKYFHHMG KCCPDSEFKK
   181  HFPVGNPEIL PSSLPSQAAE NQTSTMEKDV RPKTRSINRF PLHSESSSKK APRSKNKTLD
   241  PLLMSEPKPR TSSPRGDKAA YDILRRCSQC GILLPLPILN QHQEKCRWLA SSKGKQVRNF
   301  S

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against XAF1 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)
0.49
Highest tissue expression
69 nTPM

Expression across tissuesHPA

Tissue

  • liver: 69 nTPM
  • spleen: 67 nTPM
  • ovary: 59 nTPM
  • salivary gland: 45 nTPM
  • heart muscle: 39 nTPM
  • lung: 38 nTPM

Single-cell type

  • vascular endothelial cells: 154 nCPM
  • ovarian stromal cells: 128 nCPM
  • microglia: 125 nCPM
  • leydig cells: 87 nCPM
  • endometrial stromal cells: 76 nCPM
  • pituitary stem cells: 75 nCPM

Immune cell

  • basophil: 17 nTPM
  • intermediate monocyte: 13 nTPM
  • non-classical monocyte: 13 nTPM
  • neutrophil: 11 nTPM
  • T-reg: 9.9 nTPM
  • classical monocyte: 9.6 nTPM

Brain region

  • medulla oblongata: 61 nTPM
  • spinal cord: 49 nTPM
  • thalamus: 48 nTPM
  • pons: 47 nTPM
  • cerebral cortex: 46 nTPM
  • basal ganglia: 43 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)
1.7
gnomAD pLI
0
gnomAD missense Z
0.11
DepMap mean gene effect
-0.05
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 XAF1 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 XAF1 as an antibody target. Whether an autoantibody or antibody against XAF1 could matter depends on whether native XAF1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

XAF1 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 XAF1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/XAF1. 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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