Seroatlas · Human Serome Atlas

KRT19

Keratin, type I cytoskeletal 19

Also known as: CK19, K19, K1C19_HUMAN, K1CS, MGC15366

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

Protein identityUniProt · HPA

UniProt accession: P08727
Gene: KRT19
Ensembl: ENSG00000171345
Chromosome: 17
Canonical length: 400 aa
Protein class: Cancer-related genes, Plasma proteins, Predicted intracellular proteins
Subcellular location: Intermediate filaments

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. Unlike its related family members, this smallest known acidic cytokeratin is not paired with a basic cytokeratin in epithelial cells. It is specifically expressed in the periderm, the transiently superficial layer that envelopes the developing epidermis. The type I cytokeratins are clustered in a region of chromosome 17q12-q21. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

400 residues, UniProt reviewed canonical sequence.

>P08727|KRT19
     1  MTSYSYRQSS ATSSFGGLGG GSVRFGPGVA FRAPSIHGGS GGRGVSVSSA RFVSSSSSGA
    61  YGGGYGGVLT ASDGLLAGNE KLTMQNLNDR LASYLDKVRA LEAANGELEV KIRDWYQKQG
   121  PGPSRDYSHY YTTIQDLRDK ILGATIENSR IVLQIDNARL AADDFRTKFE TEQALRMSVE
   181  ADINGLRRVL DELTLARTDL EMQIEGLKEE LAYLKKNHEE EISTLRGQVG GQVSVEVDSA
   241  PGTDLAKILS DMRSQYEVMA EQNRKDAEAW FTSRTEELNR EVAGHTEQLQ MSRSEVTDLR
   301  RTLQGLEIEL QSQLSMKAAL EDTLAETEAR FGAQLAHIQA LISGIEAQLG DVRADSERQN
   361  QEYQRLMDIK SRLEQEIATY RSLLEGQEDH YNNLSASKVL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KRT19 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: Cell surface
Secreted: No
Transmembrane segments: 0
Mean surface accessibility (rSASA): 0.53
Highest tissue expression: 857 nTPM

Expression across tissuesHPA

Tissue

esophagus: 857 nTPM
salivary gland: 772 nTPM
small intestine: 737 nTPM
urinary bladder: 730 nTPM
stomach: 596 nTPM
colon: 495 nTPM

Single-cell type

extravillous trophoblasts: 10,172 nCPM
esophageal apical cells: 8,716 nCPM
respiratory secretory cells: 8,050 nCPM
enterocytes: 7,898 nCPM
urothelial cells: 5,849 nCPM
colonocytes: 5,384 nCPM

Immune cell

NK-cell: 0.6 nTPM
memory CD8 T-cell: 0.1 nTPM
basophil: 0 nTPM
classical monocyte: 0 nTPM
eosinophil: 0 nTPM
gdT-cell: 0 nTPM

Brain region

cerebellum: 14 nTPM
midbrain: 4 nTPM
basal ganglia: 2.5 nTPM
pons: 2.1 nTPM
cerebral cortex: 1.5 nTPM
thalamus: 1.3 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about KRT19.

Disease | ImmuneIEDB

Conditions an epitope on KRT19 was assayed in.

psoriasis T cell

ReferencesPubMed · IEDB

Publications for KRT19 from three distinct lines of evidence, kept separate because they answer different questions: whether antibodies are directed at the protein, whether a B-cell epitope has been mapped on it, and whether a T-cell epitope has. Each is labelled with its source.

Reference: AutoantibodyPubMed

6 publications

Increased levels of IgG to cytokeratin 19 in sera of patients with toluene diisocyanate-induced asthma.
2004 · Ann Allergy Asthma Immunol · RCR 0.7 · 25 citations
Increased Circulating Autoantibodies Levels of IgG, IgA, IgM Against Cytokeratin 18 and Cytokeratin 19 in Chronic Obstructive Pulmonary Disease.
2017 · Arch Med Res · RCR 0.7 · 17 citations
Anti-cytokeratin antibodies in sera of the patients with autoimmune hepatitis.
2001 · Clin Exp Immunol · RCR 0.6 · 23 citations
Identification of nasopharyngeal carcinoma antigens that induce humoral immune response by proteomic analysis.
2007 · Proteomics Clin Appl · RCR 0.2 · 9 citations
Binding of recombinant human cytokeratin 19 to laminin: a possible role in interaction between intermediate filament derived from epithelial cells and extracellular matrixes.
2000 · Cell Struct Funct · RCR 0.2 · 8 citations

Show 1 more

Circulating autoantibodies in patients with aspirin-intolerant asthma: an epiphenomenon related to airway inflammation.
2006 · J Korean Med Sci · RCR 0.1 · 4 citations

Reference: T cellIEDB

1 publication

Peripheral blood T cell responses to keratin peptides that share sequences with streptococcal M proteins are largely restricted to skin-homing CD8(+) T cells.
2004 · Clin Exp Immunol · RCR 2.6 · 126 citations

Sources: PubMed — antigen-level antibody evidence from a custom retrieval. Records matching a controlled set of autoantibody terms (the MeSH descriptors Autoantibodies and Autoantigens, with title and abstract term variants) were obtained through NCBI E-utilities, and their titles and abstracts parsed for constructions that direct an antibody at a named protein rather than for co-occurrence. Captured names were resolved against UniProt nomenclature and each antigen adjudicated individually against the source text. IEDB — curated epitope assays from the Immune Epitope Database (Vita et al., Nucleic Acids Research 2019). Bibliographic records from PubMed and MeSH, U.S. National Library of Medicine; citation metrics from NIH iCite (Hutchins et al., PLoS Biology 2016). Titles link to PubMed; abstracts are not reproduced here. The NLM does not endorse this analysis.

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): 0.73
gnomAD pLI: 0
gnomAD missense Z: 0.23
DepMap mean gene effect: -0.06
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

InteractionsUniProt · HPA

Protein binding partners of KRT19 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 KRT19 as an antibody target. Whether an autoantibody or antibody against KRT19 could matter depends on whether native KRT19 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KRT19 is annotated at the cell surface, where native KRT19 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label KRT19 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Loading the interactive Seroatlas protein explorer...