Seroatlas · Human Serome Atlas

JAM3

Junctional adhesion molecule C

Also known as: JAM-3, JAM-C, JAM3_HUMAN, JAMC

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

Protein identityUniProt · HPA

UniProt accession
Q9BX67
Gene
JAM3
Ensembl
ENSG00000166086
Chromosome
11
Canonical length
310 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins, Predicted membrane proteins, Predicted secreted proteins
Subcellular location
Golgi apparatus
Secretome location
Secreted to blood

OverviewNCBI Gene

Tight junctions represent one mode of cell-to-cell adhesion in epithelial or endothelial cell sheets, forming continuous seals around cells and serving as a physical barrier to prevent solutes and water from passing freely through the paracellular space. The protein encoded by this immunoglobulin superfamily gene member is localized in the tight junctions between high endothelial cells. Unlike other proteins in this family, the this protein is unable to adhere to leukocyte cell lines and only forms weak homotypic interactions. The encoded protein is a member of the junctional adhesion molecule protein family and acts as a receptor for another member of this family. A mutation in an intron of this gene is associated with hemorrhagic destruction of the brain, subependymal calcification, and congenital cataracts. Alternative splicing results in multiple transcript variants.[provided by RefSeq, Apr 2011]

Canonical amino-acid sequenceUniProt

310 residues, UniProt reviewed canonical sequence.

>Q9BX67|JAM3
     1  MALRRPPRLR LCARLPDFFL LLLFRGCLIG AVNLKSSNRT PVVQEFESVE LSCIITDSQT
    61  SDPRIEWKKI QDEQTTYVFF DNKIQGDLAG RAEILGKTSL KIWNVTRRDS ALYRCEVVAR
   121  NDRKEIDEIV IELTVQVKPV TPVCRVPKAV PVGKMATLHC QESEGHPRPH YSWYRNDVPL
   181  PTDSRANPRF RNSSFHLNSE TGTLVFTAVH KDDSGQYYCI ASNDAGSARC EEQEMEVYDL
   241  NIGGIIGGVL VVLAVLALIT LGICCAYRRG YFINNKQDGE SYKNPGKPDG VNYIRTDEEG
   301  DFRHKSSFVI

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against JAM3 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
1
Mean surface accessibility (rSASA)
0.4
Highest tissue expression
97 nTPM

Expression across tissuesHPA

Tissue

  • placenta: 97 nTPM
  • blood vessel: 80 nTPM
  • spinal cord: 73 nTPM
  • colon: 50 nTPM
  • midbrain: 48 nTPM
  • choroid plexus: 47 nTPM

Single-cell type

  • oligodendrocytes: 384 nCPM
  • rod photoreceptor cells: 321 nCPM
  • choroid plexus epithelial cells: 256 nCPM
  • platelets: 217 nCPM
  • sertoli cells: 204 nCPM
  • respiratory ionocytes: 188 nCPM

Immune cell

  • memory B-cell: 5.3 nTPM
  • naive B-cell: 3 nTPM
  • naive CD4 T-cell: 2.4 nTPM
  • total PBMC: 1.8 nTPM
  • MAIT T-cell: 1.7 nTPM
  • memory CD4 T-cell: 1.7 nTPM

Brain region

  • white matter: 178 nTPM
  • basal ganglia: 122 nTPM
  • midbrain: 104 nTPM
  • medulla oblongata: 100 nTPM
  • thalamus: 96 nTPM
  • cerebral cortex: 93 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about JAM3.

Disease | AllUniProt

Conditions JAM3 is implicated in, by any mechanism.

  • Hemorrhagic destruction of the brain with subependymal calcification and cataracts (HDBSCC) MIM:613730

Disease | GeneticClinVar

16 pathogenic / likely-pathogenic of 238 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Porencephaly-microcephaly-bilateral congenital cataract syndrome

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)
0.84
gnomAD pLI
0
gnomAD missense Z
-0.87
DepMap mean gene effect
0.14
DepMap dependency class
none

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 JAM3 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 JAM3 as an antibody target. Whether an autoantibody or antibody against JAM3 could matter depends on whether native JAM3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

JAM3 is annotated at the cell surface, where native JAM3 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 JAM3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/JAM3. 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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