CD79a
| B-cell antigen receptor complex-associated protein alpha chain | ||
|---|---|---|
| other names |
Ig-alpha, MB-1 membrane glycoprotein, membrane-bound immunoglobulin-associated protein, surface IgM-associated protein, CD79a |
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| Properties of human protein | ||
| Mass / length primary structure | 226 amino acids , 25,038 Da | |
| Identifier | ||
| External IDs | ||
| Orthologue (human) | ||
| Entrez | 973 | |
| Ensemble | ENSG00000105369 | |
| UniProt | P11912 | |
| Refseq (mRNA) | NM_001783.3 | |
| Refseq (protein) | NP_001774.1 | |
| PubMed search |
973
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CD79a (synonymous with B-cell antigen receptor complex -associated protein α chain ) is a surface protein and is involved in the humoral immune response .
properties
CD79a is produced by B cells . It binds to CD79b and is connected to it by disulfide bridges . Two of these heterodimers bind to membrane-bound antibodies of the subtypes m IgM or m IgD and thus form the B-cell receptor (BCR) to which antigens bind. The antigen-antibody BCR is then endocytosed .
CD79a is necessary for cell differentiation between pro-B cells and pre-B cells . It binds to CD79b and BLNK , among others . It promotes the phosphorylation and auto-activation of the protein kinase Syk . By binding BLNK it is brought close to Syk and phosphorylated by Syk. It is glycosylated , phosphorylated and methylated . It has an intracellular ITAM motif which is phosphorylated after activation of the BCR (in humans on Tyr 188 and Tyr199, in mice on Tyr182 and Tyr193). In contrast, phosphorylations of Ser 197, Ser203 and Thr 209 inhibit tyrosine phosphorylations in humans, in mice at Ser191, Ser197 and Thr203.
Certain CD79a gene defects are associated with some form of agammaglobulinaemia .
Applications
CD79a is a cell type marker of B cells and their precursor cells and B cell lymphomas . It is often used in combination with CD20 as an immunolabel target .
Web links
Individual evidence
- ↑ Louis B. Justement: Signal Transduction and the Coordination of B Lymphocyte Development and Function I. Springer Science & Business Media, 2012, ISBN 978-3-642-57066-7 , pp. 4–12.
- ^ V. Seda, M. Mraz: B-cell receptor signaling and its crosstalk with other pathways in normal and malignant cells. In: European journal of haematology. Volume 94, number 3, March 2015, pp. 193-205, doi : 10.1111 / ejh.12427 , PMID 25080849 .
- ↑ Müller R, Wienands J, Reth M: The serine and threonine residues in the Ig-alpha cytoplasmic tail negatively regulate immunoreceptor tyrosine-based activation motif-mediated signal transduction . In: Proceedings of the National Academy of Sciences . 97, No. 15, July 2000, pp. 8451-4. doi : 10.1073 / pnas.97.15.8451 . PMID 10900006 . PMC 26968 (free full text).
- ^ Heizmann B, Reth M, Infantino S: Syk is a dual-specificity kinase that self-regulates the signal output from the B-cell antigen receptor . In: Proceedings of the National Academy of Sciences . 107, No. 43, October 2010, pp. 18563-8. doi : 10.1073 / pnas.1009048107 . PMID 20940318 . PMC 2972992 (free full text).
- ↑ Leong Anthony SY, Kumarason Cooper, F Joel WM Leong: Manual of Diagnostic Cytology , 2nd edition, Greenwich Medical Media, Ltd., 2003, ISBN 1-84110-100-1 , p XX.