Seroatlas · Human Serome Atlas

KRT23

Keratin, type I cytoskeletal 23

Also known as: CK23, DKFZP434G032, HAIK1, K1C23_HUMAN, K23, MGC26158

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

Protein identityUniProt · HPA

UniProt accession
Q9C075
Gene
KRT23
Ensembl
ENSG00000108244
Chromosome
17
Canonical length
422 aa
Protein class
Predicted intracellular proteins
Subcellular location
Intermediate filaments,Cytosol

OverviewNCBI Gene

The protein encoded by this gene is a member of the keratin family. The keratins are intermediate filament proteins responsible for the structural integrity of epithelial cells and are subdivided into cytokeratins and hair keratins. The type I cytokeratins consist of acidic proteins which are arranged in pairs of heterotypic keratin chains. The type I cytokeratin genes are clustered in a region of chromosome 17q12-q21. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2013]

Canonical amino-acid sequenceUniProt

422 residues, UniProt reviewed canonical sequence.

>Q9C075|KRT23
     1  MNSGHSFSQT PSASFHGAGG GWGRPRSFPR APTVHGGAGG ARISLSFTTR SCPPPGGSWG
    61  SGRSSPLLGG NGKATMQNLN DRLASYLEKV RALEEANMKL ESRILKWHQQ RDPGSKKDYS
   121  QYEENITHLQ EQIVDGKMTN AQIILLIDNA RMAVDDFNLK YENEHSFKKD LEIEVEGLRR
   181  TLDNLTIVTT DLEQEVEGMR KELILMKKHH EQEMEKHHVP SDFNVNVKVD TGPREDLIKV
   241  LEDMRQEYEL IIKKKHRDLD TWYKEQSAAM SQEAASPATV QSRQGDIHEL KRTFQALEID
   301  LQTQYSTKSA LENMLSETQS RYSCKLQDMQ EIISHYEEEL TQLRHELERQ NNEYQVLLGI
   361  KTHLEKEITT YRRLLEGESE GTREESKSSM KVSATPKIKA ITQETINGRL VLCQVNEIQK
   421  HA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KRT23 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)
0.55
Highest tissue expression
165 nTPM

Expression across tissuesHPA

Tissue

  • skin: 165 nTPM
  • salivary gland: 135 nTPM
  • testis: 21 nTPM
  • prostate: 20 nTPM
  • placenta: 15 nTPM
  • breast: 13 nTPM

Single-cell type

  • syncytiotrophoblasts: 590 nCPM
  • migrating cytotrophoblasts: 120 nCPM
  • endometrial secretory cells: 105 nCPM
  • breast secretory cells: 83 nCPM
  • cytotrophoblasts: 72 nCPM
  • late primary spermatocytes: 55 nCPM

Immune cell

  • neutrophil: 0.9 nTPM
  • eosinophil: 0.5 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM

Brain region

  • hippocampal formation: 0.2 nTPM
  • amygdala: 0.1 nTPM
  • basal ganglia: 0.1 nTPM
  • cerebral cortex: 0.1 nTPM
  • hypothalamus: 0.1 nTPM
  • medulla oblongata: 0.1 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)
1.34
gnomAD pLI
0
gnomAD missense Z
0.24
DepMap mean gene effect
-0.03
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads KRT23 as an antibody target. Whether an autoantibody or antibody against KRT23 could matter depends on whether native KRT23 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KRT23 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 KRT23 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KRT23. 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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