ID   IL21_PIG                Reviewed;         152 AA.
AC   Q76LU6;
DT   23-NOV-2004, integrated into UniProtKB/Swiss-Prot.
DT   10-APR-2019, sequence version 3.
DT   25-MAY-2022, entry version 78.
DE   RecName: Full=Interleukin-21;
DE            Short=IL-21;
DE   Flags: Precursor;
GN   Name=IL21;
OS   Sus scrofa (Pig).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC   Eutheria; Laurasiatheria; Artiodactyla; Suina; Suidae; Sus.
OX   NCBI_TaxID=9823;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, AND SUBCELLULAR LOCATION.
RX   PubMed=15107555; DOI=10.1292/jvms.66.269;
RA   Muneta Y., Kikuma R., Uenishi H., Hoshino T., Yoshihara K., Tanaka M.,
RA   Hamashima N., Mori Y.;
RT   "Molecular cloning, chromosomal location, and biological activity of
RT   porcine interleukin-21.";
RL   J. Vet. Med. Sci. 66:269-275(2004).
CC   -!- FUNCTION: Cytokine with immunoregulatory activity. May promote the
CC       transition between innate and adaptive immunity (PubMed:15107555).
CC       Induces the production of IgG(1) and IgG(3) in B-cells. Implicated in
CC       the generation and maintenance of T follicular helper (Tfh) cells and
CC       the formation of germinal-centers. Together with IL6, control the early
CC       generation of Tfh cells and are critical for an effective antibody
CC       response to acute viral infection (By similarity). May play a role in
CC       proliferation and maturation of natural killer (NK) cells in synergy
CC       with IL15. May regulate proliferation of mature B- and T-cells in
CC       response to activating stimuli. In synergy with IL15 and IL18
CC       stimulates interferon gamma production in T-cells and NK cells (By
CC       similarity). During T-cell mediated immune response may inhibit
CC       dendritic cells (DC) activation and maturation (By similarity).
CC       {ECO:0000250|UniProtKB:Q9ES17, ECO:0000250|UniProtKB:Q9HBE4,
CC       ECO:0000269|PubMed:15107555}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000269|PubMed:15107555}.
CC   -!- SIMILARITY: Belongs to the IL-15/IL-21 family. {ECO:0000305}.
CC   -!- CAUTION: It is uncertain whether Met-1 or Met-7 is the initiator.
CC       {ECO:0000305}.
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   EMBL; AB073020; BAD11128.1; -; mRNA.
DR   RefSeq; NP_999580.1; NM_214415.1.
DR   AlphaFoldDB; Q76LU6; -.
DR   SMR; Q76LU6; -.
DR   STRING; 9823.ENSSSCP00000009696; -.
DR   PaxDb; Q76LU6; -.
DR   GeneID; 403123; -.
DR   KEGG; ssc:403123; -.
DR   CTD; 59067; -.
DR   eggNOG; ENOG502SES1; Eukaryota.
DR   InParanoid; Q76LU6; -.
DR   OrthoDB; 1439856at2759; -.
DR   Proteomes; UP000008227; Unplaced.
DR   Proteomes; UP000314985; Unplaced.
DR   GO; GO:0005615; C:extracellular space; IEA:UniProtKB-KW.
DR   GO; GO:0005125; F:cytokine activity; IEA:UniProtKB-KW.
DR   GO; GO:0005126; F:cytokine receptor binding; IEA:InterPro.
DR   GO; GO:0098586; P:cellular response to virus; ISS:UniProtKB.
DR   GO; GO:0002314; P:germinal center B cell differentiation; ISS:UniProtKB.
DR   GO; GO:0002639; P:positive regulation of immunoglobulin production; ISS:UniProtKB.
DR   GO; GO:0045954; P:positive regulation of natural killer cell mediated cytotoxicity; IBA:GO_Central.
DR   GO; GO:0061470; P:T follicular helper cell differentiation; ISS:UniProtKB.
DR   Gene3D; 1.20.1250.70; -; 1.
DR   InterPro; IPR009079; 4_helix_cytokine-like_core.
DR   InterPro; IPR003443; IL-15/IL-21_fam.
DR   PANTHER; PTHR14356; PTHR14356; 1.
DR   Pfam; PF02372; IL15; 1.
DR   SUPFAM; SSF47266; SSF47266; 1.
PE   2: Evidence at transcript level;
KW   Cytokine; Disulfide bond; Reference proteome; Secreted; Signal.
FT   SIGNAL          1..23
FT                   /evidence="ECO:0000250|UniProtKB:Q76LU5"
FT   CHAIN           24..152
FT                   /note="Interleukin-21"
FT                   /id="PRO_0000015508"
FT   DISULFID        70..121
FT                   /evidence="ECO:0000250|UniProtKB:Q9HBE4"
FT   DISULFID        77..124
FT                   /evidence="ECO:0000250|UniProtKB:Q9HBE4"
SQ   SEQUENCE   152 AA;  17575 MW;  56448C4280F2CBA1 CRC64;
     MRWPGNMEKI VICLMVIFSG TVAHKSSFQG QDRLLIRLRQ LIDTVDQLKN YVHDLDPELL
     PAPEDVQRHC EQSAFSCFQK VELKSANTGD NEKIINVLIK QLKRKLPPTN AGRRQKHGLT
     CPTCDSYEKK PIKEFLERLK SLIQKMIHQH LS