Seroatlas · Human Serome Atlas

KRT40

Keratin, type I cytoskeletal 40

Also known as: FLJ36600, K1C40_HUMAN, KA36

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

Protein identityUniProt · HPA

UniProt accession
Q6A162
Gene
KRT40
Ensembl
ENSG00000204889
Chromosome
17
Canonical length
431 aa
Protein class
Predicted intracellular proteins

OverviewNCBI Gene

This gene encodes a member of the type I (acidic) keratin family, which belongs to the superfamily of intermediate filament (IF) proteins. Keratins are heteropolymeric structural proteins which form the intermediate filament. These filaments, along with actin microfilaments and microtubules, compose the cytoskeleton of epithelial cells. The type I keratin genes are clustered in a region of chromosome 17q12-q21. [provided by RefSeq, Jul 2009]

Canonical amino-acid sequenceUniProt

431 residues, UniProt reviewed canonical sequence.

>Q6A162|KRT40
     1  MTSDCSSTHC SPESCGTASG CAPASSCSVE TACLPGTCAT SRCQTPSFLS RSRGLTGCLL
    61  PCYFTGSCNS PCLVGNCAWC EDGVFTSNEK ETMQFLNDRL ASYLEKVRSL EETNAELESR
   121  IQEQCEQDIP MVCPDYQRYF NTIEDLQQKI LCTKAENSRL AVQLDNCKLA TDDFKSKYES
   181  ELSLRQLLEA DISSLHGILE ELTLCKSDLE AHVESLKEDL LCLKKNHEEE VNLLREQLGD
   241  RLSVELDTAP TLDLNRVLDE MRCQCETVLA NNRREAEEWL AVQTEELNQQ QLSSAEQLQG
   301  CQMEILELKR TASALEIELQ AQQSLTESLE CTVAETEAQY SSQLAQIQCL IDNLENQLAE
   361  IRCDLERQNQ EYQVLLDVKA RLEGEINTYW GLLDSEDSRL SCSPCSTTCT SSNTCEPCSA
   421  YVICTVENCC L

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KRT40 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
2.7 nTPM

Expression across tissuesHPA

Tissue

  • retina: 2.7 nTPM
  • pituitary gland: 2.4 nTPM
  • skin: 2.1 nTPM
  • lung: 0.2 nTPM
  • salivary gland: 0.2 nTPM
  • breast: 0.1 nTPM

Single-cell type

  • müller glia: 1.4 nCPM
  • neuroendocrine cells: 1.4 nCPM
  • ocular epithelial cells: 0.6 nCPM
  • salivary duct cells: 0.5 nCPM
  • gonadotrophs: 0.2 nCPM
  • loop of henle epithelial cells: 0.2 nCPM

Immune cell

  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • basal ganglia: 0.4 nTPM
  • cerebellum: 0.4 nTPM
  • hypothalamus: 0.4 nTPM
  • medulla oblongata: 0.4 nTPM
  • white matter: 0.4 nTPM
  • cerebral cortex: 0.3 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)
1.25
gnomAD pLI
0
gnomAD missense Z
-0.44
DepMap mean gene effect
-0.02
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 2% 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 KRT40 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 KRT40 as an antibody target. Whether an autoantibody or antibody against KRT40 could matter depends on whether native KRT40 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KRT40 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 KRT40 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KRT40. 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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