Search
CD79B; B-cell antigen receptor complex-associated protein beta chain; Ig-beta; B-cell-specific glycoprotein B29; immunoglobulin-associated B29 protein (B29. IGB)
Function:
- component of B-cell antigen receptor (BCR)
- required in cooperation with CD79A for initiation of the signal transduction cascade activated by the B-cell antigen receptor complex (BCR) which leads to internalization of the complex, trafficking to late endosomes & antigen presentation
- enhances phosphorylation of CD79A, possibly by recruiting kinases which phosphorylate CD79A or by recruiting proteins which bind to CD79A & protect it from dephosphorylation
- phosphorylated on Tyr upon B-cell activation
- part of the B-cell antigen receptor complex where the alpha/beta chain heterodimer is non-covalently associated with antigen-specific membrane-bound surface immunoglobulin of two heavy chains & two light chains
Structure:
- heterodimer of alpha & beta chains; disulfide-linked
- contains 1 Ig-like V-type domain (immunoglobulin-like)
- contains 1 ITAM domain
Compartment:
- cell membrane; single-pass type I membrane protein
- following antigen binding, the B-cell receptor translocates from detergent-soluble regions of the cell membrane to lipid rafts although signal transduction through the complex can also occur outside lipid rafts (putative)
Alternative splicing: named isoforms=2
Expression: B-cells
Pathology:
- defects in CD79B are a cause of hypogammaglobulinemia immunodeficiency & reduced B cells
General
glycoprotein
plasma membrane protein
protein subunit
Properties
SIZE: entity length = 229 aa
MW = 26 kD
COMPARTMENT: cellular membrane
MOTIF: signal sequence {1-28}
immunoglobulin superfamily domain {38-138}
MOTIF: cysteine residue {C43}
MODIFICATION: cysteine residue {C136}
cysteine residue {C65}
MODIFICATION: cysteine residue {C122}
N-glycosylation site {N73}
N-glycosylation site {N101}
cysteine residue {C122}
MODIFICATION: cysteine residue {C65}
N-glycosylation site {N127}
N-glycosylation site {N128}
cysteine residue {C136}
MODIFICATION: cysteine residue {C43}
cysteine residue {C136}
MODIFICATION: cysteine residue {C119 IN ALPHA CHAIN) (POTENTIAL}
transmembrane domain {160-180}
ITAM {185-213}
Database Correlations
OMIM correlations
UniProt P40259
PFAM correlations
Entrez Gene 974
Kegg hsa:974
References
- UniProt :accession P40259
- Entrez Gene :accession 974
- http://www.pathologyoutlines.com/cdmarkers.html
20 May 2003
- CD79Bbase; Note: CD79B mutation db
http://bioinf.uta.fi/CD79Bbase/
Component-of
CD79 or B-cell antigen receptor complex-associated protein