CD200

CD200 (Cluster of Differentiation 200), also known as OX-2 membrane glycoprotein, is a human protein encoded by the CD200 gene. It is a single-pass type I membrane protein spanning the membrane once, with its N-terminus on the extracellular side of the membrane, and then processing leads to the removal of its signal sequence. CD200 has three variants: variant 1 forms a protein that is 269 amino acids in length, variant 2 produces a protein that is 294 amino acids, and variant 3 has yet to be experimentally validated for its product.
Importantly, CD200 is an extremely conserved member of the immunoglobulin superfamily comprising both an Ig-like C2-type (immunoglobulin-like) domain, and the Ig-like V type (immunoglobulin-like) domain. It is expressed via a number of cell types, such as B cells, thymocytes, neuron, a subset of T cells, as well as endothelial cells. Moreover, CD200 serves a crucial role in immunosuppression and regulation of anti-tumor activity. And the alternative splicing may lead to multiple transcript variants encoding different isoforms. The effect of CD200 is performed via binding to its cognate receptor CD200R (also on chromosome 3 and containing two Ig-like domains), which is expressed on cells specifically resulting from the myeloid lineage and certain populations of T cells.
Gene ID: 4345
UniProt ID: P41217