CXCR4 Signaling Pathway

CXCR4 (C-X-C-motif Chemokine Receptor-4), also known as CD184 or fusin, is a GPCR (G Protein-Coupled Receptor) and is specific for stromal-derived-factor-1 (SDF-1, also called CXCL12). CXCR4 is broadly expressed in cells of both the immune and the central nervous systems and can mediate migration of resting leukocytes and haematopoietic progenitors in response to SDF-1. SDF1 binding to CXCR4 has shown to elevate intracellular Ca2+ (Calcium), activate IP3R (Mitogen Activated Protein Kinases), JNK (Jun N-terminal Kinases) and PI3K (Phosphoinositide-3 Kinase) signaling leading to cell growth, migration and polarization. CXCR4 stimulation by SDF1 also results in increased phosphorylation of Focal Adhesion components, including the related adhesion focal tyrosine kinase (RAFTK/PYK2), Crk and Paxillin. CXCR4 induces downstream signaling by several different pathways. As a GPCR, CXCR4 binding of SDF1 activates G-protein mediated signaling, including downstream pathways such as Ras and PI3K. CXCR4 is also a major receptor for strains of HIV1 (Human Immunodeficiency Virus-1) that arise during progression to immunodeficiency and AIDS dementia. HIV1 variants that use CXCR4 are typically detected at the later stages, and are associated with a rapid decline in CD4+ T cells and progression to AIDS.

Click gene symbol on the map to view ORF/cDNA clone.

Data source: KEGG, BioCarta