Seroatlas · Human Serome Atlas

CLDN12

Claudin-12

Also known as: CLD12_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P56749
Gene
CLDN12
Ensembl
ENSG00000157224
Chromosome
7
Canonical length
244 aa
Protein class
Predicted membrane proteins

OverviewNCBI Gene

This gene encodes a member of the claudin family. Claudins are integral membrane proteins and components of tight junction strands. Tight junction strands serve as a physical barrier to prevent solutes and water from passing freely through the paracellular space between epithelial or endothelial cell sheets, and also play critical roles in maintaining cell polarity and signal transductions. This gene is expressed in the inner ear and bladder epithelium, and it is over-expressed in colorectal carcinomas. This protein and claudin 2 are critical for vitamin D-dependent Ca2+ absorption between enterocytes. Multiple alternatively spliced transcript variants encoding the same protein have been found.[provided by RefSeq, Sep 2011]

Canonical amino-acid sequenceUniProt

244 residues, UniProt reviewed canonical sequence.

>P56749|CLDN12
     1  MGCRDVHAAT VLSFLCGIAS VAGLFAGTLL PNWRKLRLIT FNRNEKNLTV YTGLWVKCAR
    61  YDGSSDCLMY DTTWYSSVDQ LDLRVLQFAL PLSMLIAMGA LLLCLIGMCN TAFRSSVPNI
   121  KLAKCLVNSA GCHLVAGLLF FLAGTVSLSP SIWVIFYNIH LNKKFEPVFS FDYAVYVTIA
   181  SAGGLFMTSL ILFIWYCTCK SLPSPFWQPL YSHPPSMHTY SQPYSARSRL SAIEIDIPVV
   241  SHTT

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CLDN12 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)
0.38
Highest tissue expression
49 nTPM

Expression across tissuesHPA

Tissue

  • liver: 49 nTPM
  • retina: 29 nTPM
  • prostate: 23 nTPM
  • kidney: 23 nTPM
  • rectum: 22 nTPM
  • tongue: 22 nTPM

Single-cell type

  • early spermatids: 93 nCPM
  • late primary spermatocytes: 54 nCPM
  • proximal tubule cells: 45 nCPM
  • distal convoluted tubule cells: 42 nCPM
  • loop of henle epithelial cells: 34 nCPM
  • podocytes: 31 nCPM

Immune cell

  • myeloid DC: 1 nTPM
  • memory CD4 T-cell: 0.6 nTPM
  • T-reg: 0.5 nTPM
  • gdT-cell: 0.3 nTPM
  • intermediate monocyte: 0.3 nTPM
  • MAIT T-cell: 0.3 nTPM

Brain region

  • hypothalamus: 31 nTPM
  • cerebellum: 28 nTPM
  • cerebral cortex: 27 nTPM
  • thalamus: 26 nTPM
  • basal ganglia: 26 nTPM
  • choroid plexus: 24 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)
1.09
gnomAD pLI
0.05
gnomAD missense Z
1.14
DepMap mean gene effect
0.07
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 8% 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 CLDN12 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 CLDN12 as an antibody target. Whether an autoantibody or antibody against CLDN12 could matter depends on whether native CLDN12 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CLDN12 is annotated at the cell surface, where native CLDN12 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 CLDN12 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CLDN12. 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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