This gene encodes a membrane protein, which functions as a receptor for Epstein-Barr virus (EBV) binding on B and T lymphocytes. Genetic variations in this gene are associated with susceptibility to systemic lupus erythematosus type 9 (SLEB9). Alternatively spliced transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Sep 2009]
Function: Receptor for complement C3Dd, for the Epstein-Barr virus on human B-cells and T-cells and for HNRPU. Participates in B lymphocytes activation.
Subunit: Interacts (via Sushi domain 1 and 2) with C3dg.
Subcellular Location: Membrane; Single-pass type I membrane protein.
Tissue Specificity: Mature B-lymphocytes, T-lymphocytes, pharyngeal epithelial cells, astrocytes and follicular dendritic cells of the spleen.
DISEASE: Genetic variations in CR2 are associated with susceptibility to systemic lupus erythematosus type 9 (SLEB9) [MIM:610927]. Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with a complex genetic basis. SLE is an inflammatory, and often febrile multisystemic disorder of connective tissue characterized principally by involvement of the skin, joints, kidneys, and serosal membranes. It is thought to represent a failure of the regulatory mechanisms of the autoimmune system.
Defects in CR2 are the cause of immunodeficiency, common variable, type 7 (CVID7) [MIM:614699]. A primary immunodeficiency characterized by antibody deficiency, hypogammaglobulinemia, recurrent bacterial infections and an inability to mount an antibody response to antigen. The defect results from a failure of B-cell differentiation and impaired secretion of immunoglobulins; the numbers of circulating B cells is usually in the normal range, but can be low.
Similarity: Belongs to the receptors of complement activation (RCA) family.