Seroatlas · Human Serome Atlas

XRCC6

X-ray repair cross-complementing protein 6

Also known as: D22S671, D22S731, G22P1, KU70, ML8, XRCC6_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P12956
Gene
XRCC6
Ensembl
ENSG00000196419
Chromosome
22
Canonical length
609 aa
Protein class
Cancer-related genes, Plasma proteins, Predicted intracellular proteins
Subcellular location
Nucleoplasm

OverviewNCBI Gene

The p70/p80 autoantigen is a nuclear complex consisting of two subunits with molecular masses of approximately 70 and 80 kDa. The complex functions as a single-stranded DNA-dependent ATP-dependent helicase. The complex may be involved in the repair of nonhomologous DNA ends such as that required for double-strand break repair, transposition, and V(D)J recombination. High levels of autoantibodies to p70 and p80 have been found in some patients with systemic lupus erythematosus. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

609 residues, UniProt reviewed canonical sequence.

>P12956|XRCC6
     1  MSGWESYYKT EGDEEAEEEQ EENLEASGDY KYSGRDSLIF LVDASKAMFE SQSEDELTPF
    61  DMSIQCIQSV YISKIISSDR DLLAVVFYGT EKDKNSVNFK NIYVLQELDN PGAKRILELD
   121  QFKGQQGQKR FQDMMGHGSD YSLSEVLWVC ANLFSDVQFK MSHKRIMLFT NEDNPHGNDS
   181  AKASRARTKA GDLRDTGIFL DLMHLKKPGG FDISLFYRDI ISIAEDEDLR VHFEESSKLE
   241  DLLRKVRAKE TRKRALSRLK LKLNKDIVIS VGIYNLVQKA LKPPPIKLYR ETNEPVKTKT
   301  RTFNTSTGGL LLPSDTKRSQ IYGSRQIILE KEETEELKRF DDPGLMLMGF KPLVLLKKHH
   361  YLRPSLFVYP EESLVIGSST LFSALLIKCL EKEVAALCRY TPRRNIPPYF VALVPQEEEL
   421  DDQKIQVTPP GFQLVFLPFA DDKRKMPFTE KIMATPEQVG KMKAIVEKLR FTYRSDSFEN
   481  PVLQQHFRNL EALALDLMEP EQAVDLTLPK VEAMNKRLGS LVDEFKELVY PPDYNPEGKV
   541  TKRKHDNEGS GSKRPKVEYS EEELKTHISK GTLGKFTVPM LKEACRAYGL KSGLKKQELL
   601  EALTKHFQD

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against XRCC6 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
272 nTPM

Expression across tissuesHPA

Tissue

  • skeletal muscle: 272 nTPM
  • testis: 220 nTPM
  • thymus: 209 nTPM
  • tonsil: 208 nTPM
  • bone marrow: 206 nTPM
  • esophagus: 190 nTPM

Single-cell type

  • early primary spermatocytes: 533 nCPM
  • late primary spermatocytes: 495 nCPM
  • cytotrophoblasts: 478 nCPM
  • migrating cytotrophoblasts: 428 nCPM
  • syncytiotrophoblasts: 385 nCPM
  • extravillous trophoblasts: 336 nCPM

Immune cell

  • total PBMC: 600 nTPM
  • T-reg: 327 nTPM
  • myeloid DC: 324 nTPM
  • non-classical monocyte: 308 nTPM
  • intermediate monocyte: 297 nTPM
  • naive CD4 T-cell: 294 nTPM

Brain region

  • white matter: 107 nTPM
  • hypothalamus: 103 nTPM
  • spinal cord: 101 nTPM
  • pons: 99 nTPM
  • medulla oblongata: 95 nTPM
  • cerebral cortex: 90 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)
0.22
gnomAD pLI
1
gnomAD missense Z
3.1
DepMap mean gene effect
-1.76
DepMap dependency class
pan

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 7% 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 XRCC6 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 XRCC6 as an antibody target. Whether an autoantibody or antibody against XRCC6 could matter depends on whether native XRCC6 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

XRCC6 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.

Source-annotated serology context

The source annotations explicitly mention antibody, autoantibody, autoantigen, or autoimmune context. This is biological context, not study-specific reactivity.

  • The p70/p80 autoantigen is a nuclear complex consisting of two subunits with molecular masses of approximately 70 and 80 kDa.
  • High levels of autoantibodies to p70 and p80 have been found in some patients with systemic lupus erythematosus.

Canonical record: https://seroatlas.com/gene/XRCC6. 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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