Seroatlas · Human Serome Atlas

JPH2

Junctophilin-2

Also known as: JP-2, JPH2_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9BR39
Gene
JPH2
Ensembl
ENSG00000149596
Chromosome
20
Canonical length
696 aa
Protein class
Disease related genes, Human disease related genes, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins, Transporters

OverviewNCBI Gene

Junctional complexes between the plasma membrane and endoplasmic/sarcoplasmic reticulum are a common feature of all excitable cell types and mediate cross talk between cell surface and intracellular ion channels. The protein encoded by this gene is a component of junctional complexes and is composed of a C-terminal hydrophobic segment spanning the endoplasmic/sarcoplasmic reticulum membrane and a remaining cytoplasmic domain that shows specific affinity for the plasma membrane. This gene is a member of the junctophilin gene family. Alternative splicing has been observed at this locus and two variants encoding distinct isoforms are described. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

696 residues, UniProt reviewed canonical sequence.

>Q9BR39|JPH2
     1  MSGGRFDFDD GGAYCGGWEG GKAHGHGLCT GPKGQGEYSG SWNFGFEVAG VYTWPSGNTF
    61  EGYWSQGKRH GLGIETKGRW LYKGEWTHGF KGRYGIRQSS SSGAKYEGTW NNGLQDGYGT
   121  ETYADGGTYQ GQFTNGMRHG YGVRQSVPYG MAVVVRSPLR TSLSSLRSEH SNGTVAPDSP
   181  ASPASDGPAL PSPAIPRGGF ALSLLANAEA AARAPKGGGL FQRGALLGKL RRAESRTSVG
   241  SQRSRVSFLK SDLSSGASDA ASTASLGEAA EGADEAAPFE ADIDATTTET YMGEWKNDKR
   301  SGFGVSERSS GLRYEGEWLD NLRHGYGCTT LPDGHREEGK YRHNVLVKDT KRRMLQLKSN
   361  KVRQKVEHSV EGAQRAAAIA RQKAEIAASR TSHAKAKAEA AEQAALAANQ ESNIARTLAR
   421  ELAPDFYQPG PEYQKRRLLQ EILENSESLL EPPDRGAGAA GLPQPPRESP QLHERETPRP
   481  EGGSPSPAGT PPQPKRPRPG VSKDGLLSPG AWNGEPSGEG SRSVTPSEGA GRRSPARPAT
   541  ERMAIEALQA PPAPSREPEV ALYQGYHSYA VRTTPPEPPP FEDQPEPEVS GSESAPSSPA
   601  TAPLQAPTLR GPEPARETPA KLEPKPIIPK AEPRAKARKT EARGLTKAGA KKKARKEAAL
   661  AAEAEVEVEE VPNTILICMV ILLNIGLAIL FVHLLT

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against JPH2 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)
0.48
Highest tissue expression
113 nTPM

Expression across tissuesHPA

Tissue

  • skeletal muscle: 113 nTPM
  • heart muscle: 46 nTPM
  • tongue: 45 nTPM
  • blood vessel: 44 nTPM
  • colon: 41 nTPM
  • endometrium: 33 nTPM

Single-cell type

  • myonuclei: 387 nCPM
  • smooth muscle cells: 264 nCPM
  • thymic myoid cells: 226 nCPM
  • vascular smooth muscle cells: 152 nCPM
  • cardiomyocytes: 138 nCPM
  • salivary myoepithelial cells: 101 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

  • medulla oblongata: 3.7 nTPM
  • midbrain: 3.6 nTPM
  • spinal cord: 3.3 nTPM
  • choroid plexus: 2.9 nTPM
  • pons: 2.8 nTPM
  • cerebral cortex: 2.7 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about JPH2.

Disease | AllUniProt

Conditions JPH2 is implicated in, by any mechanism.

  • Cardiomyopathy, familial hypertrophic, 17 (CMH17) MIM:613873
  • Cardiomyopathy, dilated, 2E (CMD2E) MIM:619492

Disease | GeneticClinVar

9 pathogenic / likely-pathogenic of 1,122 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)
0.78
gnomAD pLI
0
gnomAD missense Z
1.94
DepMap mean gene effect
0
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

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of JPH2 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 JPH2 as an antibody target. Whether an autoantibody or antibody against JPH2 could matter depends on whether native JPH2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

JPH2 is annotated at the cell surface, where native JPH2 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 JPH2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/JPH2. 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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