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P40293 (CD79A_BOVIN) Reviewed, UniProtKB/Swiss-Prot

Last modified April 16, 2014. Version 111. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (1) | Third-party data text xml rdf/xml gff fasta
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Names and origin

Protein namesRecommended name:
B-cell antigen receptor complex-associated protein alpha chain
Alternative name(s):
Ig-alpha
MB-1 membrane glycoprotein
Membrane-bound immunoglobulin-associated protein
Surface IgM-associated protein
CD_antigen=CD79a
Gene names
Name:CD79A
Synonyms:IGA, MB-1
OrganismBos taurus (Bovine) [Reference proteome]
Taxonomic identifier9913 [NCBI]
Taxonomic lineageEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaLaurasiatheriaCetartiodactylaRuminantiaPecoraBovidaeBovinaeBos

Protein attributes

Sequence length223 AA.
Sequence statusComplete.
Sequence processingThe displayed sequence is further processed into a mature form.
Protein existenceEvidence at transcript level

General annotation (Comments)

Function

Required in cooperation with CD79B for initiation of the signal transduction cascade activated by binding of antigen to the B-cell antigen receptor complex (BCR) which leads to internalization of the complex, trafficking to late endosomes and antigen presentation. Also required for BCR surface expression and for efficient differentiation of pro- and pre-B-cells. Stimulates SYK autophosphorylation and activation. Binds to BLNK, bringing BLNK into proximity with SYK and allowing SYK to phosphorylate BLNK. Also interacts with and increases activity of some Src-family tyrosine kinases. Represses BCR signaling during development of immature B-cells By similarity.

Subunit structure

Heterodimer of alpha and beta chains; disulfide-linked. Part of the B-cell antigen receptor complex where the alpha/beta chain heterodimer is non-covalently associated with an antigen-specific membrane-bound surface immunoglobulin of two heavy chains and two light chains. Interacts through its phosphorylated ITAM domain with the SH2 domains of SYK which stimulates SYK autophosphorylation and activation. Also interacts, when phosphorylated on Tyr-207, with the SH2 domain of BLNK/SLP65, bringing BLNK into proximity with SYK and allowing SYK to phosphorylate BLNK which is necessary for trafficking of the BCR to late endosomes. Interacts with Src-family tyrosine kinases including FYN and LYN, increasing their activity By similarity.

Subcellular location

Cell membrane; Single-pass type I membrane protein. Note: Following antigen binding, the BCR has been shown to translocate from detergent-soluble regions of the cell membrane to lipid rafts although signal transduction through the complex can also occur outside lipid rafts By similarity.

Tissue specificity

B-cells.

Post-translational modification

Phosphorylated on tyrosine, serine and threonine residues upon B-cell activation. Phosphorylation of tyrosine residues by Src-family kinases, including LYN, is an early and essential feature of the BCR signaling cascade. The phosphorylated tyrosines serve as docking sites for SH2-domain containing kinases, leading to their activation which in turn leads to phosphorylation of downstream targets. Phosphorylation of serine and threonine residues may prevent subsequent tyrosine phosphorylation By similarity.

Arginine methylation in the ITAM domain may interfere with the binding of SYK. It promotes signals leading to B-cell differentiation By similarity.

Sequence similarities

Contains 1 Ig-like C2-type (immunoglobulin-like) domain.

Contains 1 ITAM domain.

Alternative products

This entry describes 2 isoforms produced by alternative splicing. [Align] [Select]
Isoform 1 (identifier: P40293-1)

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.
Isoform 2 (identifier: P40293-2)

The sequence of this isoform differs from the canonical sequence as follows:
     124-133: DPLPRPFLDM → ETMAEHEIRG
     134-223: Missing.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Signal peptide1 – 3131 Potential
Chain32 – 223192B-cell antigen receptor complex-associated protein alpha chain
PRO_0000014557

Regions

Topological domain32 – 140109Extracellular Potential
Transmembrane141 – 16121Helical; Potential
Topological domain162 – 22362Cytoplasmic Potential
Domain32 – 12089Ig-like C2-type
Domain174 – 20229ITAM

Sites

Site2071Required for binding to BLNK By similarity

Amino acid modifications

Modified residue1851Phosphotyrosine; by SRC-type Tyr-kinases By similarity
Modified residue1961Phosphotyrosine By similarity
Modified residue2011Asymmetric dimethylarginine; by PRMT1 By similarity
Modified residue2071Phosphotyrosine; by Tyr-kinases By similarity
Glycosylation561N-linked (GlcNAc...) Potential
Glycosylation611N-linked (GlcNAc...) Potential
Glycosylation711N-linked (GlcNAc...) Potential
Glycosylation951N-linked (GlcNAc...) Potential
Disulfide bond53 ↔ 104 Potential
Disulfide bond116Interchain (with beta chain) Potential

Natural variations

Alternative sequence124 – 13310DPLPRPFLDM → ETMAEHEIRG in isoform 2.
VSP_027221
Alternative sequence134 – 22390Missing in isoform 2.
VSP_027222

Sequences

Sequence LengthMass (Da)Tools
Isoform 1 [UniParc].

Last modified February 1, 1995. Version 1.
Checksum: CE2F0AF175748304

FASTA22324,630
        10         20         30         40         50         60 
MPEGPQALQS PPATIFLLLI SAAGLGPGCQ ALWVEWGPPS VTVSVGEEVR LQCTHNGSNT 

        70         80         90        100        110        120 
NVTWWHVLQS NSSWPPVMYR GDVGAGGELI IKPVNKTHRG MYRCQVSDGK KIQRSCGTYL 

       130        140        150        160        170        180 
RVRDPLPRPF LDMGEGTKNN IITAEGIILL ICAVVPGTLL LFRKRWQNMK FGADIQDDYE 

       190        200        210        220 
DENLYEGLNL DDCSMYEDIS RGLQGTYQDV GSLHIGDAQL EKP 

« Hide

Isoform 2 [UniParc].

Checksum: 2138247082818E68
Show »

FASTA13314,569

References

« Hide 'large scale' references
[1]"Two forms of the mb-1 gene transcript in cattle."
Youn H.-Y., Goitsuka R., Okuda M., Watari T., Tsujimoto H., Hasegawa A.
J. Immunol. 153:5127-5132(1994) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS 1 AND 2).
Tissue: Leukocyte and Lymphoblast.
[2]"Molecular cloning of bovine mb-1 cDNA."
Youn H.-Y., Goitsuka R., Kato H., Mason D.Y., Watari T., Tsujimoto H., Hasegawa A.
Vet. Immunol. Immunopathol. 52:191-200(1996) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
[3]NIH - Mammalian Gene Collection (MGC) project
Submitted (AUG-2006) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
Strain: Hereford.
Tissue: Thymus.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
D16412 mRNA. Translation: BAA03899.1.
D16459 mRNA. Translation: BAA03926.1.
BC120260 mRNA. Translation: AAI20261.1.
PIRI45927.
RefSeqNP_776691.2. NM_174266.4.
UniGeneBt.4436.

3D structure databases

ProteinModelPortalP40293.
ModBaseSearch...
MobiDBSearch...

Proteomic databases

PRIDEP40293.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblENSBTAT00000002451; ENSBTAP00000002451; ENSBTAG00000001882. [P40293-1]
ENSBTAT00000031989; ENSBTAP00000031933; ENSBTAG00000001882. [P40293-2]
GeneID281674.
KEGGbta:281674.

Organism-specific databases

CTD973.

Phylogenomic databases

eggNOGNOG41728.
GeneTreeENSGT00510000049127.
HOGENOMHOG000074307.
HOVERGENHBG050854.
InParanoidP40293.
KOK06506.
OMAPFLDMGE.
OrthoDBEOG7J70GM.
TreeFamTF336032.

Family and domain databases

Gene3D2.60.40.10. 1 hit.
InterProIPR007110. Ig-like_dom.
IPR013783. Ig-like_fold.
IPR013098. Ig_I-set.
IPR003598. Ig_sub2.
IPR003110. Phos_immunorcpt_sig_ITAM.
[Graphical view]
PfamPF07679. I-set. 1 hit.
PF02189. ITAM. 1 hit.
[Graphical view]
SMARTSM00408. IGc2. 1 hit.
SM00077. ITAM. 1 hit.
[Graphical view]
PROSITEPS50835. IG_LIKE. 1 hit.
PS51055. ITAM_1. 1 hit.
[Graphical view]
ProtoNetSearch...

Other

NextBio20805602.

Entry information

Entry nameCD79A_BOVIN
AccessionPrimary (citable) accession number: P40293
Secondary accession number(s): Q0P5B8, Q28134
Entry history
Integrated into UniProtKB/Swiss-Prot: February 1, 1995
Last sequence update: February 1, 1995
Last modified: April 16, 2014
This is version 111 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families