Seroatlas · Human Serome Atlas

XIAP

E3 ubiquitin-protein ligase XIAP

Also known as: API3, BIRC4, hILP, ILP-1, XIAP_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P98170
Gene
XIAP
Ensembl
ENSG00000101966
Chromosome
X
Canonical length
497 aa
Protein class
Cancer-related genes, Disease related genes, Enzymes, FDA approved drug targets, Human disease related genes, Plasma proteins, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Plasma membrane,Cytosol
Quaternary structure
Homodimer

OverviewNCBI Gene

This gene encodes a protein that belongs to a family of apoptotic suppressor proteins. Members of this family share a conserved motif termed, baculovirus IAP repeat, which is necessary for their anti-apoptotic function. This protein functions through binding to tumor necrosis factor receptor-associated factors TRAF1 and TRAF2 and inhibits apoptosis induced by menadione, a potent inducer of free radicals, and interleukin 1-beta converting enzyme. This protein also inhibits at least two members of the caspase family of cell-death proteases, caspase-3 and caspase-7. Mutations in this gene are the cause of X-linked lymphoproliferative syndrome. Alternate splicing results in multiple transcript variants. Pseudogenes of this gene are found on chromosomes 2 and 11.[provided by RefSeq, Feb 2011]

Canonical amino-acid sequenceUniProt

497 residues, UniProt reviewed canonical sequence.

>P98170|XIAP
     1  MTFNSFEGSK TCVPADINKE EEFVEEFNRL KTFANFPSGS PVSASTLARA GFLYTGEGDT
    61  VRCFSCHAAV DRWQYGDSAV GRHRKVSPNC RFINGFYLEN SATQSTNSGI QNGQYKVENY
   121  LGSRDHFALD RPSETHADYL LRTGQVVDIS DTIYPRNPAM YSEEARLKSF QNWPDYAHLT
   181  PRELASAGLY YTGIGDQVQC FCCGGKLKNW EPCDRAWSEH RRHFPNCFFV LGRNLNIRSE
   241  SDAVSSDRNF PNSTNLPRNP SMADYEARIF TFGTWIYSVN KEQLARAGFY ALGEGDKVKC
   301  FHCGGGLTDW KPSEDPWEQH AKWYPGCKYL LEQKGQEYIN NIHLTHSLEE CLVRTTEKTP
   361  SLTRRIDDTI FQNPMVQEAI RMGFSFKDIK KIMEEKIQIS GSNYKSLEVL VADLVNAQKD
   421  SMQDESSQTS LQKEISTEEQ LRRLQEEKLC KICMDRNIAI VFVPCGHLVT CKQCAEAVDK
   481  CPMCYTVITF KQKIFMS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against XIAP 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)
0.38
Highest tissue expression
20 nTPM

Expression across tissuesHPA

Tissue

  • retina: 20 nTPM
  • parathyroid gland: 18 nTPM
  • thyroid gland: 15 nTPM
  • colon: 12 nTPM
  • kidney: 12 nTPM
  • liver: 12 nTPM

Single-cell type

  • neutrophils: 254 nCPM
  • esophageal apical cells: 191 nCPM
  • rod photoreceptor cells: 185 nCPM
  • myonuclei: 181 nCPM
  • urothelial cells: 151 nCPM
  • choroid plexus epithelial cells: 148 nCPM

Immune cell

  • basophil: 8.2 nTPM
  • neutrophil: 4.9 nTPM
  • memory CD8 T-cell: 3.3 nTPM
  • gdT-cell: 3 nTPM
  • naive B-cell: 2.9 nTPM
  • MAIT T-cell: 2.8 nTPM

Brain region

  • choroid plexus: 33 nTPM
  • white matter: 28 nTPM
  • spinal cord: 25 nTPM
  • hypothalamus: 25 nTPM
  • midbrain: 25 nTPM
  • medulla oblongata: 24 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about XIAP.

Disease | AllUniProt

Conditions XIAP is implicated in, by any mechanism.

  • Lymphoproliferative syndrome, X-linked, 2 (XLP2) MIM:300635

Disease | GeneticClinVar

73 pathogenic / likely-pathogenic of 514 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)
0.37
gnomAD pLI
0.92
gnomAD missense Z
1.49
DepMap mean gene effect
-0.02
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 2% 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 XIAP 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 XIAP as an antibody target. Whether an autoantibody or antibody against XIAP could matter depends on whether native XIAP is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

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

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