Seroatlas · Human Serome Atlas

CHEK2

Serine/threonine-protein kinase Chk2

Also known as: bA444G7, CDS1, CHK2, CHK2_HUMAN, HuCds1, PP1425, RAD53

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

Protein identityUniProt · HPA

UniProt accession
O96017
Gene
CHEK2
Ensembl
ENSG00000183765
Chromosome
22
Canonical length
543 aa
Protein class
Cancer-related genes, Disease related genes, Enzymes, Human disease related genes, Plasma proteins, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Nucleoplasm,Golgi apparatus
Quaternary structure
Homodimer

OverviewNCBI Gene

In response to DNA damage and replication blocks, cell cycle progression is halted through the control of critical cell cycle regulators. The protein encoded by this gene is a cell cycle checkpoint regulator and putative tumor suppressor. It contains a forkhead-associated protein interaction domain essential for activation in response to DNA damage and is rapidly phosphorylated in response to replication blocks and DNA damage. When activated, the encoded protein is known to inhibit CDC25C phosphatase, preventing entry into mitosis, and has been shown to stabilize the tumor suppressor protein p53, leading to cell cycle arrest in G1. In addition, this protein interacts with and phosphorylates BRCA1, allowing BRCA1 to restore survival after DNA damage. Mutations in this gene have been linked with Li-Fraumeni syndrome, a highly penetrant familial cancer phenotype usually associated with inherited mutations in TP53. Also, mutations in this gene are thought to confer a predisposition to sarcomas, breast cancer, and brain tumors. This nuclear protein is a member of the CDS1 subfamily of serine/threonine protein kinases. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Apr 2012]

Canonical amino-acid sequenceUniProt

543 residues, UniProt reviewed canonical sequence.

>O96017|CHEK2
     1  MSRESDVEAQ QSHGSSACSQ PHGSVTQSQG SSSQSQGISS SSTSTMPNSS QSSHSSSGTL
    61  SSLETVSTQE LYSIPEDQEP EDQEPEEPTP APWARLWALQ DGFANLECVN DNYWFGRDKS
   121  CEYCFDEPLL KRTDKYRTYS KKHFRIFREV GPKNSYIAYI EDHSGNGTFV NTELVGKGKR
   181  RPLNNNSEIA LSLSRNKVFV FFDLTVDDQS VYPKALRDEY IMSKTLGSGA CGEVKLAFER
   241  KTCKKVAIKI ISKRKFAIGS AREADPALNV ETEIEILKKL NHPCIIKIKN FFDAEDYYIV
   301  LELMEGGELF DKVVGNKRLK EATCKLYFYQ MLLAVQYLHE NGIIHRDLKP ENVLLSSQEE
   361  DCLIKITDFG HSKILGETSL MRTLCGTPTY LAPEVLVSVG TAGYNRAVDC WSLGVILFIC
   421  LSGYPPFSEH RTQVSLKDQI TSGKYNFIPE VWAEVSEKAL DLVKKLLVVD PKARFTTEEA
   481  LRHPWLQDED MKRKFQDLLS EENESTALPQ VLAQPSTSRK RPREGEAEGA ETTKRPAVCA
   541  AVL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CHEK2 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
15 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 15 nTPM
  • lymph node: 11 nTPM
  • tonsil: 11 nTPM
  • rectum: 10 nTPM
  • thymus: 8.9 nTPM
  • ovary: 8.5 nTPM

Single-cell type

  • decidual stromal cells: 68 nCPM
  • megakaryocyte progenitors: 47 nCPM
  • monocyte progenitors: 42 nCPM
  • erythrocyte progenitors: 40 nCPM
  • epicardial cells: 36 nCPM
  • undifferentiated spermatogonia: 34 nCPM

Immune cell

  • memory B-cell: 12 nTPM
  • basophil: 10 nTPM
  • intermediate monocyte: 8.3 nTPM
  • myeloid DC: 8.2 nTPM
  • naive B-cell: 8.1 nTPM
  • plasmacytoid DC: 6.2 nTPM

Brain region

  • white matter: 2.8 nTPM
  • choroid plexus: 2.6 nTPM
  • hypothalamus: 2.6 nTPM
  • pons: 2.6 nTPM
  • thalamus: 2.6 nTPM
  • medulla oblongata: 2.4 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CHEK2.

Disease | AllUniProt

Conditions CHEK2 is implicated in, by any mechanism.

Disease | GeneticClinVar

1,081 pathogenic / likely-pathogenic of 4,609 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)
1.53
gnomAD pLI
0
gnomAD missense Z
-0.45
DepMap mean gene effect
0.17
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 6% 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 CHEK2 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 CHEK2 as an antibody target. Whether an autoantibody or antibody against CHEK2 could matter depends on whether native CHEK2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CHEK2 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 CHEK2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CHEK2. 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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