calreticulin

Symbol

CALR (may also be known as: None)

Organism

Human

Description

Calreticulin is a multifunctional protein that acts as a major Ca(2+)-binding (storage) protein in the lumen of the endoplasmic reticulum. It is also found in the nucleus, suggesting that it may have a role in transcription regulation. Calreticulin binds to the synthetic peptide KLGFFKR, which is almost identical to an amino acid sequence in the DNA-binding domain of the superfamily of nuclear receptors. Calreticulin binds to antibodies in certain sera of systemic lupus and Sjogren patients which contain anti-Ro/SSA antibodies, it is highly conserved among species, and it is located in the endoplasmic and sarcoplasmic reticulum where it may bind calcium. The amino terminus of calreticulin interacts with the DNA-binding domain of the glucocorticoid receptor and prevents the receptor from binding to its specific glucocorticoid response element. Calreticulin can inhibit the binding of androgen receptor to its hormone-responsive DNA element and can inhibit androgen receptor and retinoic acid receptor transcriptional activities in vivo, as well as retinoic acid-induced neuronal differentiation. Thus, calreticulin can act as an important modulator of the regulation of gene transcription by nuclear hormone receptors. Systemic lupus erythematosus is associated with increased autoantibody titers against calreticulin but calreticulin is not a Ro/SS-A antigen. Earlier papers referred to calreticulin as an Ro/SS-A antigen but this was later disproven. Increased autoantibody titer against human calreticulin is found in infants with complete congenital heart block of both the IgG and IgM classes. [provided by RefSeq, Jul 2008]

Orthologs

SymbolSpecies
crt-1 Caenorhabditis elegans
Crc Drosophila melanogaster
calrl2 Danio rerio
Calr Mus musculus
Calr Rattus norvegicus
CNE1 Saccharomyces cerevisiae

Links to external resources

Changes associated with this gene

Identifier Name Type Tissues Organism Gene Data Actions
DAA3027 Gene expression of CALR decreases with age Molecular skin Human CALR —

GO Terms

GO IDGO TermGO Category
GO:0000122 negative regulation of transcription from RNA polymerase II promoter biological_process
GO:0002474 antigen processing and presentation of peptide antigen via MHC class I biological_process
GO:0002479 antigen processing and presentation of exogenous peptide antigen via MHC class I, TAP-dependent biological_process
GO:0002502 peptide antigen assembly with MHC class I protein complex biological_process
GO:0006355 regulation of transcription, DNA-dependent biological_process
GO:0006457 protein folding biological_process
GO:0006611 protein export from nucleus biological_process
GO:0006874 cellular calcium ion homeostasis biological_process
GO:0006987 activation of signaling protein activity involved in unfolded protein response biological_process
GO:0007050 cell cycle arrest biological_process
GO:0007283 spermatogenesis biological_process
GO:0008284 positive regulation of cell proliferation biological_process
GO:0010628 positive regulation of gene expression biological_process
GO:0017148 negative regulation of translation biological_process
GO:0018279 protein N-linked glycosylation via asparagine biological_process
GO:0022417 protein maturation by protein folding biological_process
GO:0030866 cortical actin cytoskeleton organization biological_process
GO:0030968 endoplasmic reticulum unfolded protein response biological_process
GO:0032355 response to estradiol stimulus biological_process
GO:0033144 negative regulation of intracellular steroid hormone receptor signaling pathway biological_process
GO:0033574 response to testosterone stimulus biological_process
GO:0034504 protein localization to nucleus biological_process
GO:0040020 regulation of meiosis biological_process
GO:0042493 response to drug biological_process
GO:0042590 antigen processing and presentation of exogenous peptide antigen via MHC class I biological_process
GO:0042921 glucocorticoid receptor signaling pathway biological_process
GO:0042981 regulation of apoptotic process biological_process
GO:0043687 post-translational protein modification biological_process
GO:0044267 cellular protein metabolic process biological_process
GO:0045665 negative regulation of neuron differentiation biological_process
GO:0045740 positive regulation of DNA replication biological_process
GO:0045787 positive regulation of cell cycle biological_process
GO:0045892 negative regulation of transcription, DNA-dependent biological_process
GO:0048387 negative regulation of retinoic acid receptor signaling pathway biological_process
GO:0050766 positive regulation of phagocytosis biological_process
GO:0050821 protein stabilization biological_process
GO:0051208 sequestering of calcium ion biological_process
GO:0055007 cardiac muscle cell differentiation biological_process
GO:0071285 cellular response to lithium ion biological_process
GO:0071310 cellular response to organic substance biological_process
GO:0090398 cellular senescence biological_process
GO:0001669 acrosomal vesicle cellular_component
GO:0005576 extracellular region cellular_component
GO:0005578 proteinaceous extracellular matrix cellular_component
GO:0005615 extracellular space cellular_component
GO:0005622 intracellular cellular_component
GO:0005625 soluble fraction cellular_component
GO:0005634 nucleus cellular_component
GO:0005737 cytoplasm cellular_component
GO:0005783 endoplasmic reticulum cellular_component
GO:0005788 endoplasmic reticulum lumen cellular_component
GO:0005792 microsome cellular_component
GO:0005794 Golgi apparatus cellular_component
GO:0005829 cytosol cellular_component
GO:0005844 polysome cellular_component
GO:0009897 external side of plasma membrane cellular_component
GO:0009986 cell surface cellular_component
GO:0016529 sarcoplasmic reticulum cellular_component
GO:0030670 phagocytic vesicle membrane cellular_component
GO:0031012 extracellular matrix cellular_component
GO:0042824 MHC class I peptide loading complex cellular_component
GO:0048471 perinuclear region of cytoplasm cellular_component
GO:0071556 integral to lumenal side of endoplasmic reticulum membrane cellular_component
GO:0001849 complement component C1q binding molecular_function
GO:0003677 DNA binding molecular_function
GO:0003729 mRNA binding molecular_function
GO:0005178 integrin binding molecular_function
GO:0005506 iron ion binding molecular_function
GO:0005509 calcium ion binding molecular_function
GO:0005515 protein binding molecular_function
GO:0005529 sugar binding molecular_function
GO:0008270 zinc ion binding molecular_function
GO:0030246 carbohydrate binding molecular_function
GO:0031625 ubiquitin protein ligase binding molecular_function
GO:0042277 peptide binding molecular_function
GO:0042562 hormone binding molecular_function
GO:0044183 protein binding involved in protein folding molecular_function
GO:0050681 androgen receptor binding molecular_function
GO:0051082 unfolded protein binding molecular_function
GO:0051087 chaperone binding molecular_function