Seroatlas · Human Serome Atlas

CLDN19

Claudin-19

Also known as: CLD19_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q8N6F1
Gene
CLDN19
Ensembl
ENSG00000164007
Chromosome
1
Canonical length
224 aa
Protein class
Disease related genes, Human disease related genes, Potential drug targets, Predicted membrane proteins, Transporters
Subcellular location
Plasma membrane

OverviewNCBI Gene

The product of this gene belongs to the claudin family. It plays a major role in tight junction-specific obliteration of the intercellular space, through calcium-independent cell-adhesion activity. Defects in this gene are the cause of hypomagnesemia renal with ocular involvement (HOMGO). HOMGO is a progressive renal disease characterized by primary renal magnesium wasting with hypomagnesemia, hypercalciuria and nephrocalcinosis associated with severe ocular abnormalities such as bilateral chorioretinal scars, macular colobomata, significant myopia and nystagmus. Alternatively spliced transcript variants encoding distinct isoforms have been identified for this gene. [provided by RefSeq, Jun 2010]

Canonical amino-acid sequenceUniProt

224 residues, UniProt reviewed canonical sequence.

>Q8N6F1|CLDN19
     1  MANSGLQLLG YFLALGGWVG IIASTALPQW KQSSYAGDAI ITAVGLYEGL WMSCASQSTG
    61  QVQCKLYDSL LALDGHIQSA RALMVVAVLL GFVAMVLSVV GMKCTRVGDS NPIAKGRVAI
   121  AGGALFILAG LCTLTAVSWY ATLVTQEFFN PSTPVNARYE FGPALFVGWA SAGLAVLGGS
   181  FLCCTCPEPE RPNSSPQPYR PGPSAAAREP VVKLPASAKG PLGV

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CLDN19 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
4
Mean surface accessibility (rSASA)
0.37
Highest tissue expression
42 nTPM

Expression across tissuesHPA

Tissue

  • kidney: 42 nTPM
  • choroid plexus: 12 nTPM
  • placenta: 9.2 nTPM
  • spinal cord: 1.8 nTPM
  • thymus: 1.5 nTPM
  • blood vessel: 1.2 nTPM

Single-cell type

  • extravillous trophoblasts: 361 nCPM
  • retinal pigment epithelial cells: 98 nCPM
  • migrating cytotrophoblasts: 47 nCPM
  • breast myoepithelial cells: 28 nCPM
  • schwann cells: 25 nCPM
  • loop of henle epithelial cells: 16 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

  • choroid plexus: 43 nTPM
  • hippocampal formation: 3 nTPM
  • pons: 1.8 nTPM
  • cerebellum: 1.3 nTPM
  • cerebral cortex: 1.3 nTPM
  • amygdala: 0.6 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CLDN19.

Disease | AllUniProt

Conditions CLDN19 is implicated in, by any mechanism.

  • Hypomagnesemia 5, renal, with or without ocular involvement (HOMG5) MIM:248190

Disease | GeneticClinVar

27 pathogenic / likely-pathogenic of 214 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
1.08
gnomAD pLI
0
gnomAD missense Z
0.78
DepMap mean gene effect
-0.22
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 CLDN19 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 CLDN19 as an antibody target. Whether an autoantibody or antibody against CLDN19 could matter depends on whether native CLDN19 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CLDN19 is annotated at the cell surface, where native CLDN19 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 CLDN19 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CLDN19. 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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