Seroatlas · Human Serome Atlas

XRCC5

X-ray repair cross-complementing protein 5

Also known as: KARP-1, KU80, Ku86, KUB2, XRCC5_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P13010
Gene
XRCC5
Ensembl
ENSG00000079246
Chromosome
2
Canonical length
732 aa
Protein class
Cancer-related genes, Plasma proteins, Predicted intracellular proteins
Subcellular location
Nucleoplasm

OverviewNCBI Gene

The protein encoded by this gene is the 80-kilodalton subunit of the Ku heterodimer protein which is also known as ATP-dependant DNA helicase II or DNA repair protein XRCC5. Ku is the DNA-binding component of the DNA-dependent protein kinase, and it functions together with the DNA ligase IV-XRCC4 complex in the repair of DNA double-strand break by non-homologous end joining and the completion of V(D)J recombination events. This gene functionally complements Chinese hamster xrs-6, a mutant defective in DNA double-strand break repair and in ability to undergo V(D)J recombination. A rare microsatellite polymorphism in this gene is associated with cancer in patients of varying radiosensitivity. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

732 residues, UniProt reviewed canonical sequence.

>P13010|XRCC5
     1  MVRSGNKAAV VLCMDVGFTM SNSIPGIESP FEQAKKVITM FVQRQVFAEN KDEIALVLFG
    61  TDGTDNPLSG GDQYQNITVH RHLMLPDFDL LEDIESKIQP GSQQADFLDA LIVSMDVIQH
   121  ETIGKKFEKR HIEIFTDLSS RFSKSQLDII IHSLKKCDIS LQFFLPFSLG KEDGSGDRGD
   181  GPFRLGGHGP SFPLKGITEQ QKEGLEIVKM VMISLEGEDG LDEIYSFSES LRKLCVFKKI
   241  ERHSIHWPCR LTIGSNLSIR IAAYKSILQE RVKKTWTVVD AKTLKKEDIQ KETVYCLNDD
   301  DETEVLKEDI IQGFRYGSDI VPFSKVDEEQ MKYKSEGKCF SVLGFCKSSQ VQRRFFMGNQ
   361  VLKVFAARDD EAAAVALSSL IHALDDLDMV AIVRYAYDKR ANPQVGVAFP HIKHNYECLV
   421  YVQLPFMEDL RQYMFSSLKN SKKYAPTEAQ LNAVDALIDS MSLAKKDEKT DTLEDLFPTT
   481  KIPNPRFQRL FQCLLHRALH PREPLPPIQQ HIWNMLNPPA EVTTKSQIPL SKIKTLFPLI
   541  EAKKKDQVTA QEIFQDNHED GPTAKKLKTE QGGAHFSVSS LAEGSVTSVG SVNPAENFRV
   601  LVKQKKASFE EASNQLINHI EQFLDTNETP YFMKSIDCIR AFREEAIKFS EEQRFNNFLK
   661  ALQEKVEIKQ LNHFWEIVVQ DGITLITKEE ASGSSVTAEE AKKFLAPKDK PSGDTAAVFE
   721  EGGDVDDLLD MI

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against XRCC5 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)
0.36
Highest tissue expression
165 nTPM

Expression across tissuesHPA

Tissue

  • thymus: 165 nTPM
  • tonsil: 132 nTPM
  • liver: 132 nTPM
  • urinary bladder: 123 nTPM
  • thyroid gland: 121 nTPM
  • lymph node: 119 nTPM

Single-cell type

  • neutrophil progenitors: 552 nCPM
  • neutrophils: 543 nCPM
  • erythrocyte progenitors: 489 nCPM
  • megakaryocyte progenitors: 420 nCPM
  • monocyte progenitors: 368 nCPM
  • hepatocytes: 346 nCPM

Immune cell

  • total PBMC: 330 nTPM
  • basophil: 253 nTPM
  • non-classical monocyte: 218 nTPM
  • neutrophil: 193 nTPM
  • intermediate monocyte: 177 nTPM
  • eosinophil: 175 nTPM

Brain region

  • white matter: 122 nTPM
  • spinal cord: 113 nTPM
  • basal ganglia: 109 nTPM
  • cerebral cortex: 109 nTPM
  • hypothalamus: 107 nTPM
  • cerebellum: 105 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about XRCC5.

Disease | ImmuneIEDB

Conditions an epitope on XRCC5 was assayed in.

Disease | AutoantibodyPubMed

Conditions in which antibodies against XRCC5 are reported. Each links to that disease's full target list.

Showing 1 of 2 — disease pages carrying at least 10 antigens.

ReferencesPubMed · IEDB

Publications for XRCC5 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

7 publications

Show 2 more

Reference: B cellIEDB

2 publications

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)
0.15
gnomAD pLI
1
gnomAD missense Z
2.81
DepMap mean gene effect
-1.23
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

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of XRCC5 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 XRCC5 as an antibody target. Whether an autoantibody or antibody against XRCC5 could matter depends on whether native XRCC5 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

XRCC5 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 XRCC5 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/XRCC5. 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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