CD79A Gene

The CD79A gene (CD79a molecule) is a protein-coding gene located on chromosome 19q13.2. Alternatively spliced transcript variants encoding different isoforms have been described.

The encoded protein CD79A is required in cooperation with CD79B for initiation of the signal transduction cascade activated by binding of antigen to the B-cell antigen receptor (BCR) complex, leading to internalization of the complex, trafficking to endosomes, and antigen presentation.

Furthermore, CD79A is required for BCR surface expression and efficient differentiation of pro- and pre-B cells. It stimulates autophosphorylation and activation of SYK. CD79A also interacts with and increases the activity of some Src family tyrosine kinases. Suppresses BCR signaling during immature B cell development.

Diseases associated with CD79A include:

Autosomal recessive agammaglobulinemia 3, mutation in CD79A.

The B lymphocyte antigen receptor (BCR) is a multimeric complex containing the antigen-specific component, surface immunoglobulin (Ig). The surface Ig associates non-covalently with two other proteins, Ig-alpha and Ig-beta, which are necessary for the expression and function of the B-cell antigen receptor (see Fig.).

1. Chu PG et al (2001) CD79: a review. Appl Immunohistochem Mol Morphol 9: 97-106.
2. Minegishi Y et al (1999) Mutations in Ig-alpha (CD79a) result in a complete block in B-cell development. J Clin Invest 104: 1115-1121.
3. Wang Y et al (2002) Novel Ig-alpha (CD79a) gene mutation in a Turkish patient with B cell-deficient agammaglobulinemia. Am J Med Genet 108: 333-336.