P12637 · CASQ2_CANLF

Function

function

Calsequestrin is a high-capacity, moderate affinity, calcium-binding protein and thus acts as an internal calcium store in muscle (PubMed:3427023).
Calcium ions are bound by clusters of acidic residues at the protein surface, especially at the interface between subunits. Can bind around 60 Ca2+ ions. Regulates the release of lumenal Ca2+ via the calcium release channel RYR2; this plays an important role in triggering muscle contraction. Plays a role in excitation-contraction coupling in the heart and in regulating the rate of heart beats.

GO annotations

all annotationsall molecular functionvirus receptor activitydna bindingrna bindingcytoskeletal motor activitycatalytic activitygtpase activitystructural molecule activitytransporter activitycytoskeletal protein bindinglipid bindingcyclase activityantioxidant activityoxidoreductase activitytransferase activityhydrolase activitylyase activityisomerase activityligase activityprotein tag activitycargo receptor activityhistone bindingprotein folding chaperonetranslation regulator activitynutrient reservoir activityreceptor ligand activitymolecular transducer activitymolecular adaptor activitytoxin activitycell adhesion mediator activitymolecular function regulator activityvirus coreceptor activitycatalytic activity, acting on a proteincatalytic activity, acting on dnacatalytic activity, acting on rnamolecular carrier activitytranscription regulator activitygeneral transcription initiation factor activitymolecular sensor activitymolecular sequestering activityatp-dependent activityother molecular functionall biological processmitotic cell cyclecytokinesiscytoplasmic translationimmune system processmuscle system processcirculatory system processrenal system processrespiratory system processcarbohydrate metabolic processgeneration of precursor metabolites and energydna replicationdna repairdna recombinationchromatin organizationdna-templated transcriptionregulation of dna-templated transcriptiontrna metabolic processprotein foldingprotein glycosylationamino acid metabolic processmodified amino acid metabolic processlipid metabolic processvitamin metabolic processsulfur compound metabolic processintracellular protein transportnucleocytoplasmic transportautophagyinflammatory responsemitochondrion organizationcytoskeleton organizationmicrotubule-based movementperoxisome organizationlysosome organizationchromosome segregationcell adhesionestablishment or maintenance of cell polarityprogrammed cell deathphotosynthesismrna metabolic processsnrna metabolic processvesicle-mediated transportreproductive processdigestive system processsignalingcell differentiationprotein catabolic processextracellular matrix organizationregulatory ncrna-mediated gene silencingtelomere organizationcell junction organizationwound healingribosome biogenesiscilium organizationanatomical structure developmentcell motilitynervous system processendocrine processprotein maturationtransmembrane transportnucleobase-containing small molecule metabolic processhepaticobiliary system processmembrane organizationprotein-containing complex assemblycell wall organization or biogenesisnitrogen cycle metabolic processprotein localization to plasma membranedefense response to other organismdetoxificationmeiotic nuclear divisionmitotic nuclear divisionmitochondrial gene expressioncarbohydrate derivative metabolic processother biological processall cellular componentnuclear chromosomeextracellular regionextracellular spacecell wallnucleusnuclear envelopenucleoplasmchromosomenucleolusmitochondrionlysosomeendosomevacuoleperoxisomeendoplasmic reticulumgolgi apparatuslipid dropletmicrotubule organizing centercytosolribosomecytoskeletonplasma membraneciliumplastidthylakoidexternal encapsulating structureextracellular matrixcytoplasmic vesicleorganelleother cellular component
Cell color indicative of number of GO terms
AspectTerm
Cellular Componentsarcoplasmic reticulum
Cellular Componentsarcoplasmic reticulum lumen
Cellular ComponentZ disc
Molecular Functioncalcium ion binding
Biological Processnegative regulation of ryanodine-sensitive calcium-release channel activity
Biological Processregulation of cardiac muscle contraction by regulation of the release of sequestered calcium ion
Biological Processregulation of release of sequestered calcium ion into cytosol by sarcoplasmic reticulum

Keywords

Names & Taxonomy

Protein names

  • Recommended name
    Calsequestrin-2
  • Alternative names
    • Calsequestrin, cardiac muscle isoform

Gene names

    • Name
      CASQ2

Organism names

Accessions

  • Primary accession
    P12637

Proteomes

Subcellular Location

Note: This isoform of calsequestrin occurs in the sarcoplasmic reticulum's terminal cisternae luminal spaces of cardiac and slow skeletal muscle cells.

Keywords

Phenotypes & Variants

Features

Showing features for mutagenesis.

TypeIDPosition(s)Description
Mutagenesis206Creates an additional N-glycosylation site. Decreases calcium binding and increases the rate of spontaneous Ca2+ release from myocytes.

PTM/Processing

Features

Showing features for signal, chain, modified residue, glycosylation.

TypeIDPosition(s)Description
Signal1-19
ChainPRO_000000421720-410Calsequestrin-2
Modified residue282Phosphotyrosine
Glycosylation335N-linked (GlcNAc...) asparagine
Glycosylation395N-linked (GlcNAc...) asparagine
Modified residue397Phosphoserine; by CK2
Modified residue401Phosphoserine; by CK2
Modified residue405Phosphoserine; by CK2

Post-translational modification

Phosphorylation in the C-terminus, probably by CK2, moderately increases calcium buffering capacity.
N-glycosylated.

Keywords

Proteomic databases

PTM databases

Expression

Tissue specificity

Detected in heart muscle (at protein level).

Interaction

Subunit

Interacts with ASPH (By similarity).
Monomer, homodimer and homooligomer. Mostly monomeric in the absence of calcium. Forms higher oligomers in a calcium-dependent manner. Dimers associate to form tetramers, that then form linear homomer chains. Interacts with TRDN

Protein-protein interaction databases

Family & Domains

Features

Showing features for region, compositional bias.

TypeIDPosition(s)Description
Region221-242Calcium regulated hydrophobic site
Region364-410Disordered
Compositional bias374-410Acidic residues

Sequence similarities

Belongs to the calsequestrin family.

Keywords

Phylogenomic databases

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Sequence processing
    The displayed sequence is further processed into a mature form.
  • Length
    410
  • Mass (Da)
    47,417
  • Last updated
    1989-10-01 v1
  • Checksum
    FCA99A8D7E7ABB82
MKRTHLFIAGLYLLASCRAEEGLNFPTYDGKDRVVSLTEKNFKQVLKKYDVLCLYYHESVSSDKVAQKQFQLKEIVLELVAQVLEHKDIGFVMVDAKKEAKLAKKLGFDEEGSLYVLKGDRTIEFDGEFAADVLVEFLLDLIEDPVEIINSKLEVQAFERIEDQIKLIGFFKSEESEYYKAFEEAAEHFQPYIKFFATFDKGVAKKLSLKMNEVDFYEPFMDEPIAIPDKPYTEEELVEFVKEHQRPTLRRLRPEDMFETWEDDLNGIHIVAFAERSDPDGYEFLEILKQVARDNTDNPDLSIVWIDPDDFPLLVAYWEKTFKIDLFKPQIGVVNVTDADSVWMEIPDDDDLPTAEELEDWIEDVLSGKINTEDDDNEEGDDGDDDEDDDDDDGNNSDEESNDDSDDDDE

Features

Showing features for sequence conflict, compositional bias.

TypeIDPosition(s)Description
Sequence conflict71in Ref. 2; AA sequence
Compositional bias374-410Acidic residues

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
J03766
EMBL· GenBank· DDBJ
AAA30833.1
EMBL· GenBank· DDBJ
mRNA

Genome annotation databases

Similar Proteins

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