Seroatlas · Human Serome Atlas

CCNK

Cyclin-K

Also known as: CCNK_HUMAN, CPR4

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

Protein identityUniProt · HPA

UniProt accession
O75909
Gene
CCNK
Ensembl
ENSG00000090061
Chromosome
14
Canonical length
580 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins
Subcellular location
Nucleoplasm

OverviewNCBI Gene

The protein encoded by this gene is a member of the transcription cyclin family. These cyclins may regulate transcription through their association with and activation of cyclin-dependent kinases (CDK) that phosphorylate the C-terminal domain (CTD) of the large subunit of RNA polymerase II. This gene product may play a dual role in regulating CDK and RNA polymerase II activities. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

580 residues, UniProt reviewed canonical sequence.

>O75909|CCNK
     1  MKENKENSSP SVTSANLDHT KPCWYWDKKD LAHTPSQLEG LDPATEARYR REGARFIFDV
    61  GTRLGLHYDT LATGIIYFHR FYMFHSFKQF PRYVTGACCL FLAGKVEETP KKCKDIIKTA
   121  RSLLNDVQFG QFGDDPKEEV MVLERILLQT IKFDLQVEHP YQFLLKYAKQ LKGDKNKIQK
   181  LVQMAWTFVN DSLCTTLSLQ WEPEIIAVAV MYLAGRLCKF EIQEWTSKPM YRRWWEQFVQ
   241  DVPVDVLEDI CHQILDLYSQ GKQQMPHHTP HQLQQPPSLQ PTPQVPQVQQ SQPSQSSEPS
   301  QPQQKDPQQP AQQQQPAQQP KKPSPQPSSP RQVKRAVVVS PKEENKAAEP PPPKIPKIET
   361  THPPLPPAHP PPDRKPPLAA ALGEAEPPGP VDATDLPKVQ IPPPAHPAPV HQPPPLPHRP
   421  PPPPPSSYMT GMSTTSSYMS GEGYQSLQSM MKTEGPSYGA LPPAYGPPAH LPYHPHVYPP
   481  NPPPPPVPPP PASFPPPAIP PPTPGYPPPP PTYNPNFPPP PPRLPPTHAV PPHPPPGLGL
   541  PPASYPPPAV PPGGQPPVPP PIPPPGMPPV GGLGRAAWMR

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CCNK 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)
0.51
Highest tissue expression
96 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 96 nTPM
  • testis: 42 nTPM
  • skeletal muscle: 36 nTPM
  • tonsil: 32 nTPM
  • thymus: 31 nTPM
  • lymph node: 27 nTPM

Single-cell type

  • epicardial cells: 432 nCPM
  • neutrophils: 231 nCPM
  • esophageal apical cells: 174 nCPM
  • enterocytes: 160 nCPM
  • neutrophil progenitors: 154 nCPM
  • esophageal suprabasal cells: 123 nCPM

Immune cell

  • neutrophil: 13 nTPM
  • eosinophil: 13 nTPM
  • gdT-cell: 7.3 nTPM
  • naive CD4 T-cell: 6.5 nTPM
  • memory CD8 T-cell: 6.4 nTPM
  • MAIT T-cell: 6.3 nTPM

Brain region

  • cerebral cortex: 33 nTPM
  • white matter: 28 nTPM
  • medulla oblongata: 27 nTPM
  • hypothalamus: 26 nTPM
  • cerebellum: 25 nTPM
  • pons: 25 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CCNK.

Disease | AllUniProt

Conditions CCNK is implicated in, by any mechanism.

  • Intellectual developmental disorder with hypertelorism and distinctive facies (IDDHDF) MIM:618147

Disease | GeneticClinVar

1 pathogenic / likely-pathogenic of 97 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Intellectual developmental disorder with hypertelorism and distinctive facies

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)
0.17
gnomAD pLI
1
gnomAD missense Z
3.31
DepMap mean gene effect
-1.59
DepMap dependency class
pan

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

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

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