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Q9HBE4 · IL21_HUMAN

  • Protein
    Interleukin-21
  • Gene
    IL21
  • Status
    UniProtKB reviewed (Swiss-Prot)
  • Amino acids
  • Protein existence
    Evidence at protein level
  • Annotation score
    5/5

Function

function

Cytokine with immunoregulatory activity. May promote the transition between innate and adaptive immunity. Induces the production of IgG1 and IgG3 in B-cells (By similarity).
Implicated in the generation and maintenance of T follicular helper (Tfh) cells and the formation of germinal-centers. Together with IL6, control the early generation of Tfh cells and are critical for an effective antibody response to acute viral infection (By similarity).
May play a role in proliferation and maturation of natural killer (NK) cells in synergy with IL15. May regulate proliferation of mature B- and T-cells in response to activating stimuli. In synergy with IL15 and IL18 stimulates interferon gamma production in T-cells and NK cells (PubMed:11081504, PubMed:15178704).
During T-cell mediated immune response may inhibit dendritic cells (DC) activation and maturation (By similarity).

Caution

It is uncertain whether Met-1 or Met-8 is the initiator.

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 Componentextracellular region
Cellular Componentextracellular space
Molecular Functioncytokine activity
Molecular Functioncytokine receptor binding
Molecular Functioninterleukin-2 receptor binding
Biological Processcell maturation
Biological Processcellular response to virus
Biological Processdefense response to virus
Biological Processgerminal center B cell differentiation
Biological Processpositive regulation of B cell proliferation
Biological Processpositive regulation of cell population proliferation
Biological Processpositive regulation of cytokine production
Biological Processpositive regulation of immunoglobulin production
Biological Processpositive regulation of inflammatory response
Biological Processpositive regulation of interleukin-17 production
Biological Processpositive regulation of natural killer cell mediated cytotoxicity
Biological Processpositive regulation of T cell proliferation
Biological Processpositive regulation of tissue remodeling
Biological Processpositive regulation of type II interferon production
Biological Processpositive regulation of tyrosine phosphorylation of STAT protein
Biological Processsignal transduction
Biological ProcessT follicular helper cell differentiation
Biological Processtyrosine phosphorylation of STAT protein

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Interleukin-21
  • Short names
    IL-21
  • Alternative names
    • Za11

Gene names

    • Name
      IL21

Organism names

  • Taxonomic identifier
  • Taxonomic lineage
    Eukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Euarchontoglires > Primates > Haplorrhini > Catarrhini > Hominidae > Homo

Accessions

  • Primary accession
    Q9HBE4
  • Secondary accessions
    • A5J0L4

Proteomes

Organism-specific databases

Subcellular Location

Keywords

Disease & Variants

Involvement in disease

Immunodeficiency, common variable, 11 (CVID11)

  • Note
    • The disease is caused by variants affecting the gene represented in this entry
  • Description
    A primary immunodeficiency characterized by antibody deficiency, hypogammaglobulinemia, recurrent bacterial infections and an inability to mount an antibody response to antigen. The defect results from a failure of B-cell differentiation and impaired secretion of immunoglobulins; the numbers of circulating B-cells is usually in the normal range, but can be low.
  • See also
    MIM:615767
Natural variants in CVID11
Variant IDPosition(s)ChangeDescription
VAR_07129256L>Pin CVID11; interferes with binding to IL21R

Features

Showing features for natural variant.

TypeIDPosition(s)Description
Natural variantVAR_07129256in CVID11; interferes with binding to IL21R

Variants

We now provide the "Disease & Variants" viewer in its own tab.

The viewer provides 152 variants from UniProt as well as other sources including ClinVar and dbSNP.

Go to variant viewer

Keywords

Organism-specific databases

Miscellaneous

Chemistry

Genetic variation databases

PTM/Processing

Features

Showing features for signal, chain, disulfide bond, glycosylation.

Type
IDPosition(s)Description
Signal1-24
ChainPRO_000001550525-162Interleukin-21
Disulfide bond71↔122
Disulfide bond78↔125
Glycosylation97N-linked (GlcNAc...) asparagine

Keywords

Proteomic databases

PTM databases

Expression

Tissue specificity

Expressed in activated CD4-positive T-cells but not in CD8-positive T-cells, B-cells, or monocytes.

Gene expression databases

Organism-specific databases

Interaction

Binary interactions

TypeEntry 1Entry 2Number of experimentsIntAct
BINARY Q9HBE4ASPH Q12797-63EBI-6595560, EBI-12092171

Complex viewer

View interactors in UniProtKB
View CPX-833 in Complex Portal

Protein-protein interaction databases

Chemistry

Miscellaneous

Family & Domains

Features

Showing features for region.

TypeIDPosition(s)Description
Region105-126Disordered

Sequence similarities

Belongs to the IL-15/IL-21 family.

Keywords

Phylogenomic databases

Family and domain databases

Sequence & Isoform

Align isoforms (2)
  • Sequence status
    Complete
  • Sequence processing
    The displayed sequence is further processed into a mature form.

This entry describes 2 isoforms produced by Alternative splicing.

Q9HBE4-1

This isoform has been chosen as the canonical sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.

  • Length
    162
  • Mass (Da)
    18,653
  • Last updated
    2019-04-10 v3
  • MD5 Checksum
    BFA62B99A19A54E6D7EAA2B50D283CD2
MRSSPGNMERIVICLMVIFLGTLVHKSSSQGQDRHMIRMRQLIDIVDQLKNYVNDLVPEFLPAPEDVETNCEWSAFSCFQKAQLKSANTGNNERIINVSIKKLKRKPPSTNAGRRQKHRLTCPSCDSYEKKPPKEFLERFKSLLQKMIHQHLSSRTHGSEDS

Q9HBE4-2

  • Name
    2
  • Synonyms
    IL-21iso
  • See also
    sequence in UniParc or sequence clusters in UniRef
  • Differences from canonical
    • 147-162: MIHQHLSSRTHGSEDS → VSTLSFI

Features

Showing features for alternative sequence.

TypeIDPosition(s)Description
Alternative sequenceVSP_030129147-162in isoform 2

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
AF254069
EMBL· GenBank· DDBJ
AAG29348.1
EMBL· GenBank· DDBJ
mRNA
DQ645417
EMBL· GenBank· DDBJ
ABG36529.1
EMBL· GenBank· DDBJ
mRNA
AY763518
EMBL· GenBank· DDBJ
AAU88182.1
EMBL· GenBank· DDBJ
Genomic DNA
AC053545
EMBL· GenBank· DDBJ
-Genomic DNA No translation available.
BC066258
EMBL· GenBank· DDBJ
AAH66258.1
EMBL· GenBank· DDBJ
mRNA
BC066259
EMBL· GenBank· DDBJ
AAH66259.1
EMBL· GenBank· DDBJ
mRNA
BC066260
EMBL· GenBank· DDBJ
AAH66260.1
EMBL· GenBank· DDBJ
mRNA
BC066261
EMBL· GenBank· DDBJ
AAH66261.1
EMBL· GenBank· DDBJ
mRNA
BC066262
EMBL· GenBank· DDBJ
AAH66262.1
EMBL· GenBank· DDBJ
mRNA
BC069124
EMBL· GenBank· DDBJ
AAH69124.1
EMBL· GenBank· DDBJ
mRNA

Genome annotation databases

Similar Proteins

Disclaimer

Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care. Our staff consists of biologists and biochemists that are not trained to give medical advice.
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