Seroatlas · Human Serome Atlas

CASQ2

Calsequestrin-2

Also known as: CASQ2_HUMAN, PDIB2

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

Protein identityUniProt · HPA

UniProt accession
O14958
Gene
CASQ2
Ensembl
ENSG00000118729
Chromosome
1
Canonical length
399 aa
Protein class
Disease related genes, Human disease related genes, Potential drug targets, Predicted intracellular proteins, Transporters
Secretome location
Intracellular and membrane
Quaternary structure
Homodimer

OverviewNCBI Gene

The protein encoded by this gene specifies the cardiac muscle family member of the calsequestrin family. Calsequestrin is localized to the sarcoplasmic reticulum in cardiac and slow skeletal muscle cells. The protein is a calcium binding protein that stores calcium for muscle function. Mutations in this gene cause stress-induced polymorphic ventricular tachycardia, also referred to as catecholaminergic polymorphic ventricular tachycardia 2 (CPVT2), a disease characterized by bidirectional ventricular tachycardia that may lead to cardiac arrest. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

399 residues, UniProt reviewed canonical sequence.

>O14958|CASQ2
     1  MKRTHLFIVG IYFLSSCRAE EGLNFPTYDG KDRVVSLSEK NFKQVLKKYD LLCLYYHEPV
    61  SSDKVTQKQF QLKEIVLELV AQVLEHKAIG FVMVDAKKEA KLAKKLGFDE EGSLYILKGD
   121  RTIEFDGEFA ADVLVEFLLD LIEDPVEIIS SKLEVQAFER IEDYIKLIGF FKSEDSEYYK
   181  AFEEAAEHFQ PYIKFFATFD KGVAKKLSLK MNEVDFYEPF MDEPIAIPNK PYTEEELVEF
   241  VKEHQRPTLR RLRPEEMFET WEDDLNGIHI VAFAEKSDPD GYEFLEILKQ VARDNTDNPD
   301  LSILWIDPDD FPLLVAYWEK TFKIDLFRPQ IGVVNVTDAD SVWMEIPDDD DLPTAEELED
   361  WIEDVLSGKI NTEDDDEDDD DDDNSDEEDN DDSDDDDDE

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CASQ2 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.32
Highest tissue expression
989 nTPM

Expression across tissuesHPA

Tissue

  • heart muscle: 989 nTPM
  • skeletal muscle: 178 nTPM
  • blood vessel: 174 nTPM
  • tongue: 154 nTPM
  • colon: 57 nTPM
  • urinary bladder: 51 nTPM

Single-cell type

  • thymic myoid cells: 779 nCPM
  • cardiomyocytes: 301 nCPM
  • myonuclei: 278 nCPM
  • vascular smooth muscle cells: 220 nCPM
  • smooth muscle cells: 135 nCPM
  • early spermatids: 51 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

  • thalamus: 12 nTPM
  • midbrain: 7.5 nTPM
  • amygdala: 5.5 nTPM
  • hypothalamus: 5.2 nTPM
  • cerebellum: 3.7 nTPM
  • basal ganglia: 2.6 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CASQ2.

Disease | AllUniProt

Conditions CASQ2 is implicated in, by any mechanism.

  • Ventricular tachycardia, catecholaminergic polymorphic, 2 (CPVT2) MIM:611938

Disease | GeneticClinVar

79 pathogenic / likely-pathogenic of 864 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)
1.38
gnomAD pLI
0
gnomAD missense Z
-0.2
DepMap mean gene effect
-0.06
DepMap dependency class
selective

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 CASQ2 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 CASQ2 as an antibody target. Whether an autoantibody or antibody against CASQ2 could matter depends on whether native CASQ2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CASQ2 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label CASQ2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CASQ2. 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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