CD20 Flag Tag Protein

Quality Statement:
CD20 is a 33-37 kDa non-glycosylated proteinexpressed on the surface of normal and malignant B lymphocytes, and belongs tothe MS4A (membrane-spanning 4-domain family A) protein family. CD20 proteinconsists of four hydrophobic transmembrane domains, one intracellular and twoextracellular domains (large and small loops) with both N- and C- terminiresiding within the cytosol. CD20 is also known to be physically coupled tomajor histocompatibility complex class II (MHCII), CD40 molecule, BCR, and theC-terminal src kinase-binding protein (CBP) that interacts with Src kinasessuch as LYN, FYN, and LCK. CD20 deficiency resulted in a reduced number ofcirculating memory B cells, reduced isotype switching of Ig, and decreased IgGantibody levels. In agreement with this observation, challenging the patient’sprimary B cells in vitro using T-dependent and Tindependent antigens led to thenormal proliferation and secretion of IgM but reduced production of IgG.

Reference:
1.KarlsenA.E., et al.,(1991), Cloning and primary structure of a human islet isoform ofglutamic acid decarboxylase from chromosome 10. Proc. Natl. Acad. Sci. U.S.A.88:8337-8341.2.BuD.-F., et al., (1992), Two human glutamate decarboxylases, 65-kDa GAD and67-kDa GAD, are each encoded by a single gene.Proc. Natl. Acad. Sci. U.S.A.89:2115-2119. 3.Bu D.-F., et al.,(1994), The exon-intronorganization of the genes (GAD1 and GAD2) encoding two human glutamatedecarboxylases (GAD67 and GAD65) suggests that they derive from a commonancestral GAD.Genomics 21:222-228.