Seroatlas · Human Serome Atlas

CDKN3

Cyclin-dependent kinase inhibitor 3

Also known as: CDI1, CDKN3_HUMAN, KAP

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

Protein identityUniProt · HPA

UniProt accession
Q16667
Gene
CDKN3
Ensembl
ENSG00000100526
Chromosome
14
Canonical length
212 aa
Protein class
Disease related genes, Enzymes, Potential drug targets, Predicted intracellular proteins
Subcellular location
Cytosol

OverviewNCBI Gene

The protein encoded by this gene belongs to the dual specificity protein phosphatase family. It was identified as a cyclin-dependent kinase inhibitor, and has been shown to interact with, and dephosphorylate CDK2 kinase, thus prevent the activation of CDK2 kinase. This gene was reported to be deleted, mutated, or overexpressed in several kinds of cancers. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Aug 2008]

Canonical amino-acid sequenceUniProt

212 residues, UniProt reviewed canonical sequence.

>Q16667|CDKN3
     1  MKPPSSIQTS EFDSSDEEPI EDEQTPIHIS WLSLSRVNCS QFLGLCALPG CKFKDVRRNV
    61  QKDTEELKSC GIQDIFVFCT RGELSKYRVP NLLDLYQQCG IITHHHPIAD GGTPDIASCC
   121  EIMEELTTCL KNYRKTLIHC YGGLGRSCLV AACLLLYLSD TISPEQAIDS LRDLRGSGAI
   181  QTIKQYNYLH EFRDKLAAHL SSRDSQSRSV SR

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CDKN3 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)
0.3
Highest tissue expression
192 nTPM

Expression across tissuesHPA

Tissue

  • testis: 192 nTPM
  • bone marrow: 41 nTPM
  • thymus: 29 nTPM
  • tonsil: 28 nTPM
  • lymph node: 26 nTPM
  • rectum: 16 nTPM

Single-cell type

  • early spermatids: 2,828 nCPM
  • late primary spermatocytes: 2,256 nCPM
  • late spermatids: 792 nCPM
  • monocyte progenitors: 117 nCPM
  • gastric progenitor cells: 114 nCPM
  • esophageal basal cells: 108 nCPM

Immune cell

  • T-reg: 19 nTPM
  • NK-cell: 6.2 nTPM
  • memory CD4 T-cell: 5.6 nTPM
  • memory CD8 T-cell: 4.9 nTPM
  • total PBMC: 3.2 nTPM
  • naive CD4 T-cell: 2.9 nTPM

Brain region

  • cerebellum: 6.6 nTPM
  • hypothalamus: 4.4 nTPM
  • cerebral cortex: 4.3 nTPM
  • choroid plexus: 4.3 nTPM
  • pons: 4.2 nTPM
  • midbrain: 3.5 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CDKN3.

Disease | AllUniProt

Conditions CDKN3 is implicated in, by any mechanism.

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)
0.83
gnomAD pLI
0
gnomAD missense Z
1.19
DepMap mean gene effect
0
DepMap dependency class
selective

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 CDKN3 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 CDKN3 as an antibody target. Whether an autoantibody or antibody against CDKN3 could matter depends on whether native CDKN3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CDKN3 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 CDKN3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CDKN3. 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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