CD79 is a transmembrane protein

Transmembrane protein

A transmembrane protein is a protein that goes from one side of a membrane through to the other side of the membrane. Many TPs function as gateways or "loading docks" to deny or permit the transport of specific substances across the biological membrane, to get into the cell, or out of the cell as...

 that forms a complex with the B-cell receptor

B-cell receptor

The B-cell receptor is a transmembrane receptor protein located on the outer surface of B-cells. The receptor's binding moiety is composed of a membrane-bound antibody that, like all antibodies, has a unique and randomly-determined antigen-binding site...

 (BCR) and generates a signal

Signal transduction

Signal transduction occurs when an extracellular signaling molecule activates a cell surface receptor. In turn, this receptor alters intracellular molecules creating a response...

 following recognition of antigen

Antigen

An antigen is a foreign molecule that, when introduced into the body, triggers the production of an antibody by the immune system. The immune system will then kill or neutralize the antigen that is recognized as a foreign and potentially harmful invader. These invaders can be molecules such as...

 by the BCR. CD79 is composed of two distinct chains called CD79A

CD79A

CD79a molecule, immunoglobulin-associated alpha, also known as mb-1, is a human gene.The mb-1 gene codes for a phosphoprotein, designated CD79a CD79a molecule, immunoglobulin-associated alpha, also known as mb-1, is a human gene.The mb-1 gene codes for a phosphoprotein, designated CD79a CD79a...

 and CD79B

CD79B

CD79b molecule, immunoglobulin-associated beta, also known as CD79B , is a human gene.It is associated with agammaglobulinemia-6.-External links:...

 (formerly known as Ig-alpha and Ig-beta); these form a heterodimer on the surface of a B cell

B cell

B cells are lymphocytes that play a large role in the humoral immune response . The principal functions of B cells are to make antibodies against antigens, perform the role of antigen-presenting cells and eventually develop into memory B cells after activation by antigen interaction...

 stabilized by disulfide bond

Disulfide bond

In chemistry, a disulfide bond is a covalent bond, usually derived by the coupling of two thiol groups. The linkage is also called an SS-bond or disulfide bridge. The overall connectivity is therefore R-S-S-R. The terminology is widely used in biochemistry...

ing. CD79a and CD79b are both members of the immunoglobulin superfamily

Immunoglobulin superfamily

The immunoglobulin superfamily is a large group of cell surface and soluble proteins that are involved in the recognition, binding, or adhesion processes of cells. Molecules are categorized as members of this superfamily based on shared structural features with immunoglobulins ; they all possess a...

. Human CD79a is encoded by the mb-1 gene that is located on chromosome 19, and CD79b is encoded by the B29 gene that located on chromosome 17. Both CD79 chains contain an immunoreceptor tyrosine-based activation motif

Immunoreceptor tyrosine-based activation motif

An immunoreceptor tyrosine-based activation motif is a conserved sequence of four amino acids that is repeated twice in the cytoplasmic tails of certain cell surface proteins of the immune system....

 (ITAM) in their intracellular

Intracellular

Not to be confused with intercellular, meaning "between cells".In cell biology, molecular biology and related fields, the word intracellular means "inside the cell".It is used in contrast to extracellular...

 tails that they use to propagate a signal in a B cell, in a similar manner to CD3

CD3 receptor

In immunology, the CD3 T-Cell Co-Receptor is a protein complex and is composed of four distinct chains. In mammals, the complex contains a CD3γ chain, a CD3δ chain, and two CD3ε chains. These chains associate with a molecule known as the T cell receptor and the ζ-chain to generate an activation...

 generated signal tranduction observed during T cell receptor

T cell receptor

The T cell receptor or TCR is a molecule found on the surface of T lymphocytes that is responsible for recognizing antigens bound to major histocompatibility complex molecules...

 activation on T cell

T cell

T cells or T lymphocytes belong to a group of white blood cells known as lymphocytes, and play a central role in cell-mediated immunity. They can be distinguished from other lymphocytes, such as B cells and natural killer cells , by the presence of a T cell receptor on the cell surface. They are...

s.