CD19_CAVPO
ID CD19_CAVPO Reviewed; 430 AA.
AC P25917;
DT 01-MAY-1992, integrated into UniProtKB/Swiss-Prot.
DT 01-MAY-1992, sequence version 1.
DT 03-AUG-2022, entry version 108.
DE RecName: Full=B-lymphocyte antigen CD19;
DE AltName: Full=Differentiation antigen CD19;
DE AltName: CD_antigen=CD19;
DE Flags: Fragment;
GN Name=CD19;
OS Cavia porcellus (Guinea pig).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC Eutheria; Euarchontoglires; Glires; Rodentia; Hystricomorpha; Caviidae;
OC Cavia.
OX NCBI_TaxID=10141;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA].
RX PubMed=1714482;
RA Zhou L.J., Ord D.C., Hughes A.L., Tedder T.F.;
RT "Structure and domain organization of the CD19 antigen of human, mouse, and
RT guinea pig B lymphocytes. Conservation of the extensive cytoplasmic
RT domain.";
RL J. Immunol. 147:1424-1432(1991).
CC -!- FUNCTION: Functions as coreceptor for the B-cell antigen receptor
CC complex (BCR) on B-lymphocytes. Decreases the threshold for activation
CC of downstream signaling pathways and for triggering B-cell responses to
CC antigens (By similarity). Activates signaling pathways that lead to the
CC activation of phosphatidylinositol 3-kinase and the mobilization of
CC intracellular Ca(2+) stores. Is not required for early steps during B
CC cell differentiation in the blood marrow. Required for normal
CC differentiation of B-1 cells. Required for normal B cell
CC differentiation and proliferation in response to antigen challenges.
CC Required for normal levels of serum immunoglobulins, and for production
CC of high-affinity antibodies in response to antigen challenge (By
CC similarity). {ECO:0000250|UniProtKB:P15391,
CC ECO:0000250|UniProtKB:P25918}.
CC -!- SUBUNIT: Interacts with CR2/CD21. Part of a complex composed of CD19,
CC CR2/CD21, CD81 and IFITM1/CD225 in the membrane of mature B-cells.
CC Interacts directly with CD81 (via the second extracellular domain);
CC this interaction is initiated early during biosynthesis in the ER/pre-
CC Golgi compartments and is essential for trafficking and
CC compartmentalization of CD19 receptor on the cell surface of activated
CC B cells. Interacts with VAV. Interacts with GRB2 and SOS when
CC phosphorylated on Tyr-348 and/or Tyr-378. Interacts with PLCG2 when
CC phosphorylated on Tyr-409. Interacts with LYN. Interacts (when tyrosine
CC phosphorylated) with the regulatory p85 subunit of phosphatidylinositol
CC 3-kinase (PIK3R1 or PIK3R2). {ECO:0000250|UniProtKB:P15391}.
CC -!- SUBCELLULAR LOCATION: Cell membrane {ECO:0000250|UniProtKB:P25918};
CC Single-pass type I membrane protein {ECO:0000250|UniProtKB:P25918}.
CC Membrane raft {ECO:0000250|UniProtKB:P25918}; Single-pass type I
CC membrane protein {ECO:0000250|UniProtKB:P25918}.
CC -!- PTM: Phosphorylated on tyrosine following B-cell activation (By
CC similarity). Phosphorylated on tyrosine residues by LYN (By
CC similarity). Tyrosine residues are phosphorylated sequentially after
CC activation of the B cell receptor. Phosphorylation of Tyr-405 is
CC extremely rapid (By similarity). {ECO:0000250|UniProtKB:P15391,
CC ECO:0000250|UniProtKB:P25918}.
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; M62543; AAA51529.1; -; mRNA.
DR PIR; I48142; I48142.
DR AlphaFoldDB; P25917; -.
DR SMR; P25917; -.
DR STRING; 10141.ENSCPOP00000001807; -.
DR eggNOG; ENOG502STG8; Eukaryota.
DR InParanoid; P25917; -.
DR Proteomes; UP000005447; Unassembled WGS sequence.
DR GO; GO:0005887; C:integral component of plasma membrane; ISS:UniProtKB.
DR GO; GO:0045121; C:membrane raft; IEA:UniProtKB-SubCell.
DR GO; GO:0050851; P:antigen receptor-mediated signaling pathway; ISS:UniProtKB.
DR GO; GO:0019724; P:B cell mediated immunity; ISS:UniProtKB.
DR GO; GO:0002322; P:B cell proliferation involved in immune response; ISS:UniProtKB.
DR GO; GO:0050853; P:B cell receptor signaling pathway; ISS:UniProtKB.
DR GO; GO:0001923; P:B-1 B cell differentiation; ISS:UniProtKB.
DR GO; GO:0016064; P:immunoglobulin mediated immune response; ISS:UniProtKB.
DR GO; GO:0043552; P:positive regulation of phosphatidylinositol 3-kinase activity; ISS:UniProtKB.
DR GO; GO:0051281; P:positive regulation of release of sequestered calcium ion into cytosol; ISS:UniProtKB.
DR GO; GO:0050864; P:regulation of B cell activation; ISS:UniProtKB.
DR GO; GO:0050855; P:regulation of B cell receptor signaling pathway; ISS:UniProtKB.
DR InterPro; IPR042341; CD19.
DR InterPro; IPR007110; Ig-like_dom.
DR InterPro; IPR036179; Ig-like_dom_sf.
DR InterPro; IPR003599; Ig_sub.
DR PANTHER; PTHR16674; PTHR16674; 1.
DR SMART; SM00409; IG; 1.
DR SUPFAM; SSF48726; SSF48726; 1.
DR PROSITE; PS50835; IG_LIKE; 1.
PE 2: Evidence at transcript level;
KW Adaptive immunity; Cell membrane; Disulfide bond; Glycoprotein; Immunity;
KW Immunoglobulin domain; Membrane; Phosphoprotein; Reference proteome;
KW Repeat; Transmembrane; Transmembrane helix.
FT CHAIN <1..430
FT /note="B-lymphocyte antigen CD19"
FT /id="PRO_0000072676"
FT TOPO_DOM <1..168
FT /note="Extracellular"
FT /evidence="ECO:0000255"
FT TRANSMEM 169..190
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TOPO_DOM 191..430
FT /note="Cytoplasmic"
FT /evidence="ECO:0000255"
FT DOMAIN <1..17
FT /note="Ig-like C2-type 1"
FT DOMAIN 52..152
FT /note="Ig-like C2-type 2"
FT REGION 1..56
FT /note="Disordered"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT REGION 206..241
FT /note="Disordered"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT REGION 255..374
FT /note="Disordered"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT REGION 387..430
FT /note="Disordered"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT COMPBIAS 1..36
FT /note="Polar residues"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT COMPBIAS 214..241
FT /note="Polar residues"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT COMPBIAS 255..272
FT /note="Polar residues"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT COMPBIAS 280..296
FT /note="Acidic residues"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT COMPBIAS 301..315
FT /note="Polar residues"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT MOD_RES 104
FT /note="Phosphoserine"
FT /evidence="ECO:0000250|UniProtKB:P25918"
FT MOD_RES 225
FT /note="Phosphotyrosine"
FT /evidence="ECO:0000250|UniProtKB:P15391"
FT MOD_RES 255
FT /note="Phosphotyrosine"
FT /evidence="ECO:0000250|UniProtKB:P15391"
FT MOD_RES 286
FT /note="Phosphotyrosine"
FT /evidence="ECO:0000250|UniProtKB:P15391"
FT MOD_RES 316
FT /note="Phosphotyrosine"
FT /evidence="ECO:0000250|UniProtKB:P15391"
FT MOD_RES 376
FT /note="Phosphotyrosine"
FT /evidence="ECO:0000250|UniProtKB:P25918"
FT MOD_RES 405
FT /note="Phosphotyrosine"
FT /evidence="ECO:0000250|UniProtKB:P25918"
FT CARBOHYD 1
FT /note="N-linked (GlcNAc...) asparagine"
FT /evidence="ECO:0000255"
FT CARBOHYD 14
FT /note="N-linked (GlcNAc...) asparagine"
FT /evidence="ECO:0000255"
FT CARBOHYD 28
FT /note="N-linked (GlcNAc...) asparagine"
FT /evidence="ECO:0000255"
FT CARBOHYD 59
FT /note="N-linked (GlcNAc...) asparagine"
FT /evidence="ECO:0000255"
FT CARBOHYD 142
FT /note="N-linked (GlcNAc...) asparagine"
FT /evidence="ECO:0000255"
FT DISULFID 10..49
FT /evidence="ECO:0000250|UniProtKB:P15391"
FT NON_TER 1
SQ SEQUENCE 430 AA; 46958 MW; 84F05B04F94590E3 CRC64;
NSSDLGDFSC GPGNGSSEGP TPSSQHPNSS QLYVWDKRDS PSWEPEPVCA PPRGSLNENL
TQDLTVALGS TLWLSCGVPP AHVTRGPVSW TQVHPKKPDS TLLSLYLREK PPVQEMWVLG
PVLSLSQVTV QAAGTYYCLR GNLTTEIHMK VTARQAVWHW LLRSGGWKVP AVSLVYLIFC
LGSLVVFLQI RKALVLRRKR KRMTDPNRRF FKVTPPSGNG TPNQYGNVLS LPTPGSSTGR
TQRWAAALGG TIQSYGNSRS DVQETGAMGS RSPTTAGIEE EEGEGYEEPD SEEGSEFYEN
DSNRGQDQLS QDASGYENPE DGPLGSADED SFSNESYENA DEELAQPVAR TTDFLSPHGS
AWDPSREATS LGSQSYEDMR GILYAAPQLR SLQPGPHHEE DADSYENMDN PDEPEPAWGG
GGHMGIWSTR
