- OMIM: 300574
- UniProt: P49682
- MGI: 1277207
CXCR3 (short for CXC motif chemokine receptor 3, also CD183 ) is a receptor protein of the family of chemokine receptors. CXCR3 is especially at the surface of cells of the immune system such as T lymphocytes, and natural killer cells, above. This receptor can be stimulated by chemokine CXCL9 (MIG ), CXCL10 ( IP-10 ), and CXCL11 ( I-TAC ), and mediates its effects by means of activation of an intracellular signal transduction at the Gi proteins are involved. CXCR3 plays in the pathogenesis of inflammatory disorders a significant role, and is therefore a target for the development of new drugs.
CXCR3 can be detected within the hematopoietic system on various lymphocytes, especially activated T lymphocytes and NK cells, as well as epithelial and endothelial cells. Together with the CCR5 chemokine receptor CXCR3 is preferable to find those responsible for cell-mediated immune type 1 helper T cells (TH1 lymphocytes).
CXCR3 is encoded by a gene on chromosome 10 q13 locus. There are two distinct isoforms of CXCR3 is known which result from different splicing: CXCR3 A and CXCR3 -B. Both isoforms differ in the length of their N-terminal amino acid sequences. CXCR3 -B is also able to bind to the chemokine CXCL4 (PF -4).
CXCR3 structurally belongs to the G protein- coupled receptors. After binding of the chemokines CXCL9, CXCL10, CXCL11, or a signal transduction cascade is activated inside the cell, at the G- proteins, Ca2 and MAP kinases involved. The signal transduction cascade also includes activation of integrins and changes in the cytoskeleton. These are prerequisites for targeted movement (chemotaxis ) of CXCR3 -expressing cells to a chemokine gradient toward during inflammation.