FCGR2A

FCGR2A or Fc gamma receptor IIa is a protein that in humans is encoded by the FCGR2A gene. It is a member of the immunoglobulin superfamily and is a low affinity receptor for the Fc region of immunoglobulin G (IgG). This gene is found on chromosome 1, among a cluster of related genes and pseudogenes. Polymorphisms in this gene have been linked to differences in humoral immunity response and susceptibility to autoimmune diseases.

Structure

The FCGR2A protein is a cell surface receptor found on phagocytic cells such as macrophages and neutrophils, and is involved in the process of phagocytosis and immune response. It is a transmembrane protein and has a cytoplasmic tail that can interact with other proteins and signaling molecules within the cell.

Function

FCGR2A plays a crucial role in the immune system. It binds to the Fc region of IgG antibodies, which are produced by the body in response to infection. This binding triggers a series of events within the cell, leading to the destruction of the pathogen. The receptor can also bind to other types of antibodies, and its activity can be influenced by other factors such as the presence of certain cytokines.

Clinical significance

Polymorphisms in the FCGR2A gene have been associated with susceptibility to various autoimmune diseases, including rheumatoid arthritis, systemic lupus erythematosus, and glomerulonephritis. These polymorphisms can affect the function of the receptor and alter the body's immune response. In addition, mutations in this gene have been implicated in certain types of cancer, including non-Hodgkin lymphoma and chronic lymphocytic leukemia.

See also

• Fc receptor
• Immunoglobulin G
• Autoimmune disease