CLDN8

Protein identityUniProt · HPA

UniProt accession

P56748

Gene

CLDN8

Ensembl

ENSG00000156284

Chromosome

21

Canonical length

225 aa

Protein class

Predicted membrane proteins, Transporters

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 protein plays important roles in the paracellular cation barrier of the distal renal tubule, and in the paracellular barrier to prevent sodium back-leakage in distal colon. Differential expression of this gene has been observed in colorectal carcinoma and renal cell tumors, and along with claudin-7, is an immunohistochemical marker for the differential diagnosis of chromophobe renal cell carcinoma and renal oncocytoma.[provided by RefSeq, May 2010]

Canonical amino-acid sequenceUniProt

225 residues, UniProt reviewed canonical sequence.

>P56748|CLDN8
     1  MATHALEIAG LFLGGVGMVG TVAVTVMPQW RVSAFIENNI VVFENFWEGL WMNCVRQANI
    61  RMQCKIYDSL LALSPDLQAA RGLMCAASVM SFLAFMMAIL GMKCTRCTGD NEKVKAHILL
   121  TAGIIFIITG MVVLIPVSWV ANAIIRDFYN SIVNVAQKRE LGEALYLGWT TALVLIVGGA
   181  LFCCVFCCNE KSSSYRYSIP SHRTTQKSYH TGKKSPSVYS RSQYV

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CLDN8 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)

0.36

Highest tissue expression

65 nTPM

Expression across tissuesHPA

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)

1.58

gnomAD pLI

0.02

gnomAD missense Z

-0.17

DepMap mean gene effect

0.05

DepMap dependency class

none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

• bicellular tight junction assembly
• calcium-independent cell-cell adhesion via plasma membrane cell-adhesion molecules
• cell adhesion

Molecular functions

• identical protein binding
• structural molecule activity

Cellular components

• apicolateral plasma membrane
• basolateral plasma membrane
• bicellular tight junction
• endoplasmic reticulum
• plasma membrane

Protein domainsUniProt · Pfam · InterPro

• PMP-22/EMP/MP20/Claudin
• Claudin
• Claudin, conserved site
• PMP-22/EMP/MP20/Claudin family

KeywordsUniProt

• Cell junction
• Cell membrane
• Membrane
• Tight junction
• Transmembrane
• Transmembrane helix
• Ubl conjugation

InteractionsUniProt · HPA

Protein binding partners of CLDN8 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

• CLDN4
• KLHL3