CD79A_BOVIN
ID CD79A_BOVIN Reviewed; 223 AA.
AC P40293; Q0P5B8; Q28134;
DT 01-FEB-1995, integrated into UniProtKB/Swiss-Prot.
DT 01-FEB-1995, sequence version 1.
DT 03-AUG-2022, entry version 150.
DE RecName: Full=B-cell antigen receptor complex-associated protein alpha chain;
DE AltName: Full=Ig-alpha;
DE AltName: Full=MB-1 membrane glycoprotein;
DE AltName: Full=Membrane-bound immunoglobulin-associated protein;
DE AltName: Full=Surface IgM-associated protein;
DE AltName: CD_antigen=CD79a;
DE Flags: Precursor;
GN Name=CD79A; Synonyms=IGA, MB-1;
OS Bos taurus (Bovine).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC Eutheria; Laurasiatheria; Artiodactyla; Ruminantia; Pecora; Bovidae;
OC Bovinae; Bos.
OX NCBI_TaxID=9913;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS 1 AND 2).
RC TISSUE=Leukocyte, and Lymphoblast;
RX PubMed=7963570;
RA Youn H.-Y., Goitsuka R., Okuda M., Watari T., Tsujimoto H., Hasegawa A.;
RT "Two forms of the mb-1 gene transcript in cattle.";
RL J. Immunol. 153:5127-5132(1994).
RN [2]
RP NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
RX PubMed=8810000; DOI=10.1016/0165-2427(95)05546-0;
RA Youn H.-Y., Goitsuka R., Kato H., Mason D.Y., Watari T., Tsujimoto H.,
RA Hasegawa A.;
RT "Molecular cloning of bovine mb-1 cDNA.";
RL Vet. Immunol. Immunopathol. 52:191-200(1996).
RN [3]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
RC STRAIN=Hereford; TISSUE=Thymus;
RG NIH - Mammalian Gene Collection (MGC) project;
RL Submitted (AUG-2006) to the EMBL/GenBank/DDBJ databases.
CC -!- FUNCTION: Required in cooperation with CD79B for initiation of the
CC signal transduction cascade activated by binding of antigen to the B-
CC cell antigen receptor complex (BCR) which leads to internalization of
CC the complex, trafficking to late endosomes and antigen presentation.
CC Also required for BCR surface expression and for efficient
CC differentiation of pro- and pre-B-cells. Stimulates SYK
CC autophosphorylation and activation. Binds to BLNK, bringing BLNK into
CC proximity with SYK and allowing SYK to phosphorylate BLNK. Also
CC interacts with and increases activity of some Src-family tyrosine
CC kinases. Represses BCR signaling during development of immature B-cells
CC (By similarity). {ECO:0000250}.
CC -!- SUBUNIT: Heterodimer of alpha and beta chains; disulfide-linked. Part
CC of the B-cell antigen receptor complex where the alpha/beta chain
CC heterodimer is non-covalently associated with an antigen-specific
CC membrane-bound surface immunoglobulin of two heavy chains and two light
CC chains. Interacts through its phosphorylated ITAM domain with the SH2
CC domains of SYK which stimulates SYK autophosphorylation and activation.
CC Also interacts, when phosphorylated on Tyr-207, with the SH2 domain of
CC BLNK/SLP65, bringing BLNK into proximity with SYK and allowing SYK to
CC phosphorylate BLNK which is necessary for trafficking of the BCR to
CC late endosomes. Interacts with Src-family tyrosine kinases including
CC FYN and LYN, increasing their activity (By similarity). {ECO:0000250}.
CC -!- SUBCELLULAR LOCATION: Cell membrane; Single-pass type I membrane
CC protein. Note=Following antigen binding, the BCR has been shown to
CC translocate from detergent-soluble regions of the cell membrane to
CC lipid rafts although signal transduction through the complex can also
CC occur outside lipid rafts. {ECO:0000250}.
CC -!- ALTERNATIVE PRODUCTS:
CC Event=Alternative splicing; Named isoforms=2;
CC Name=1;
CC IsoId=P40293-1; Sequence=Displayed;
CC Name=2;
CC IsoId=P40293-2; Sequence=VSP_027221, VSP_027222;
CC -!- TISSUE SPECIFICITY: B-cells.
CC -!- PTM: Phosphorylated on tyrosine, serine and threonine residues upon B-
CC cell activation. Phosphorylation of tyrosine residues by Src-family
CC kinases, including LYN, is an early and essential feature of the BCR
CC signaling cascade. The phosphorylated tyrosines serve as docking sites
CC for SH2-domain containing kinases, leading to their activation which in
CC turn leads to phosphorylation of downstream targets. Phosphorylation of
CC serine and threonine residues may prevent subsequent tyrosine
CC phosphorylation (By similarity). {ECO:0000250}.
CC -!- PTM: Arginine methylation in the ITAM domain may interfere with the
CC binding of SYK. It promotes signals leading to B-cell differentiation
CC (By similarity). {ECO:0000250}.
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DR EMBL; D16412; BAA03899.1; -; mRNA.
DR EMBL; D16459; BAA03926.1; -; mRNA.
DR EMBL; BC120260; AAI20261.1; -; mRNA.
DR PIR; I45927; I45927.
DR RefSeq; NP_776691.2; NM_174266.4. [P40293-1]
DR AlphaFoldDB; P40293; -.
DR STRING; 9913.ENSBTAP00000002451; -.
DR PaxDb; P40293; -.
DR PRIDE; P40293; -.
DR Ensembl; ENSBTAT00000002451; ENSBTAP00000002451; ENSBTAG00000001882. [P40293-1]
DR GeneID; 281674; -.
DR KEGG; bta:281674; -.
DR CTD; 973; -.
DR VEuPathDB; HostDB:ENSBTAG00000001882; -.
DR eggNOG; ENOG502S1DI; Eukaryota.
DR GeneTree; ENSGT00940000154363; -.
DR HOGENOM; CLU_106774_0_0_1; -.
DR InParanoid; P40293; -.
DR OMA; RWQNEKF; -.
DR OrthoDB; 1165385at2759; -.
DR TreeFam; TF336032; -.
DR Proteomes; UP000009136; Chromosome 18.
DR Bgee; ENSBTAG00000001882; Expressed in blood and 83 other tissues.
DR ExpressionAtlas; P40293; baseline.
DR GO; GO:0019815; C:B cell receptor complex; ISS:UniProtKB.
DR GO; GO:0009897; C:external side of plasma membrane; ISS:UniProtKB.
DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR GO; GO:0045121; C:membrane raft; ISS:UniProtKB.
DR GO; GO:0005771; C:multivesicular body; ISS:UniProtKB.
DR GO; GO:0042802; F:identical protein binding; IEA:Ensembl.
DR GO; GO:0004888; F:transmembrane signaling receptor activity; IEA:InterPro.
DR GO; GO:0002250; P:adaptive immune response; IEA:UniProtKB-KW.
DR GO; GO:0042113; P:B cell activation; ISS:UniProtKB.
DR GO; GO:0030183; P:B cell differentiation; ISS:UniProtKB.
DR GO; GO:0042100; P:B cell proliferation; ISS:UniProtKB.
DR GO; GO:0050853; P:B cell receptor signaling pathway; ISS:UniProtKB.
DR Gene3D; 2.60.40.10; -; 1.
DR InterPro; IPR039695; CD79a/CD79b.
DR InterPro; IPR007110; Ig-like_dom.
DR InterPro; IPR036179; Ig-like_dom_sf.
DR InterPro; IPR013783; Ig-like_fold.
DR InterPro; IPR003599; Ig_sub.
DR InterPro; IPR003598; Ig_sub2.
DR InterPro; IPR003110; Phos_immunorcpt_sig_ITAM.
DR PANTHER; PTHR14334; PTHR14334; 1.
DR Pfam; PF02189; ITAM; 1.
DR SMART; SM00409; IG; 1.
DR SMART; SM00408; IGc2; 1.
DR SMART; SM00077; ITAM; 1.
DR SUPFAM; SSF48726; SSF48726; 1.
DR PROSITE; PS50835; IG_LIKE; 1.
DR PROSITE; PS51055; ITAM_1; 1.
PE 2: Evidence at transcript level;
KW Adaptive immunity; Alternative splicing; Cell membrane; Disulfide bond;
KW Glycoprotein; Immunity; Immunoglobulin domain; Membrane; Methylation;
KW Phosphoprotein; Reference proteome; Signal; Transmembrane;
KW Transmembrane helix.
FT SIGNAL 1..31
FT /evidence="ECO:0000255"
FT CHAIN 32..223
FT /note="B-cell antigen receptor complex-associated protein
FT alpha chain"
FT /id="PRO_0000014557"
FT TOPO_DOM 32..140
FT /note="Extracellular"
FT /evidence="ECO:0000255"
FT TRANSMEM 141..161
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TOPO_DOM 162..223
FT /note="Cytoplasmic"
FT /evidence="ECO:0000255"
FT DOMAIN 32..120
FT /note="Ig-like C2-type"
FT DOMAIN 174..202
FT /note="ITAM"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00379"
FT SITE 207
FT /note="Required for binding to BLNK"
FT /evidence="ECO:0000250"
FT MOD_RES 185
FT /note="Phosphotyrosine; by SRC-type Tyr-kinases"
FT /evidence="ECO:0000250|UniProtKB:P11911,
FT ECO:0000255|PROSITE-ProRule:PRU00379"
FT MOD_RES 196
FT /note="Phosphotyrosine"
FT /evidence="ECO:0000250|UniProtKB:P11911,
FT ECO:0000255|PROSITE-ProRule:PRU00379"
FT MOD_RES 201
FT /note="Asymmetric dimethylarginine; by PRMT1"
FT /evidence="ECO:0000250|UniProtKB:P11911"
FT MOD_RES 207
FT /note="Phosphotyrosine; by Tyr-kinases"
FT /evidence="ECO:0000250|UniProtKB:P11911,
FT ECO:0000255|PROSITE-ProRule:PRU00379"
FT CARBOHYD 56
FT /note="N-linked (GlcNAc...) asparagine"
FT /evidence="ECO:0000255"
FT CARBOHYD 61
FT /note="N-linked (GlcNAc...) asparagine"
FT /evidence="ECO:0000255"
FT CARBOHYD 71
FT /note="N-linked (GlcNAc...) asparagine"
FT /evidence="ECO:0000255"
FT CARBOHYD 95
FT /note="N-linked (GlcNAc...) asparagine"
FT /evidence="ECO:0000255"
FT DISULFID 53..104
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00114"
FT DISULFID 116
FT /note="Interchain (with beta chain)"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00114"
FT VAR_SEQ 124..133
FT /note="DPLPRPFLDM -> ETMAEHEIRG (in isoform 2)"
FT /evidence="ECO:0000303|PubMed:7963570"
FT /id="VSP_027221"
FT VAR_SEQ 134..223
FT /note="Missing (in isoform 2)"
FT /evidence="ECO:0000303|PubMed:7963570"
FT /id="VSP_027222"
SQ SEQUENCE 223 AA; 24630 MW; CE2F0AF175748304 CRC64;
MPEGPQALQS PPATIFLLLI SAAGLGPGCQ ALWVEWGPPS VTVSVGEEVR LQCTHNGSNT
NVTWWHVLQS NSSWPPVMYR GDVGAGGELI IKPVNKTHRG MYRCQVSDGK KIQRSCGTYL
RVRDPLPRPF LDMGEGTKNN IITAEGIILL ICAVVPGTLL LFRKRWQNMK FGADIQDDYE
DENLYEGLNL DDCSMYEDIS RGLQGTYQDV GSLHIGDAQL EKP
