CXCR receptor

FIGURE 3.12 Dependence of constitutive receptor activity as ordinates (expressed as a percent of the maximal response to a full agonist for each receptor) versus magnitude of receptor expression (expressed as the amount of human cDNA used for transient transfection, logarithmic scale) in Xenopus laevis melanophores. Data shown for human chemokine CCR5 receptors (open circles), chemokine CXCR receptors (filled triangles), neuropeptide Y type 1 receptors (filled diamonds), neuropeptide Y type 2 receptors (open squares), and neuropeptide Y type 4 receptors (open inverted triangles). Data recalculated and redrawn from [27],... 

FIGURE 4 Binding determinants identified in the CXCR receptors. Residues on the extracellular side of the molecule important for ligand binding (b), cell activation (a), or unspecified receptor function (f) are displayed for CXCRl ( ), CXCR2 ( ), and CXCR4 (J). 

Reeves ID, McKnight A, Potempa S et al (1997) CD4-independent infection by HlV-2 (ROD/B) use of the 7-transmembrane receptors CXCR-4, CCR-3, and V28 for entry. Virology 231 130-134 Ribeiro JA (2005) What can adenosine neuromodulation do for neuroprotection Curr Drug Targets CNS Neurol Disord 4 325-329... 

A systematic nomenclature has been developed for the chemokine receptors (see Table 1). Thus, receptors for CC chemokines are referred to as CCR, receptors for CXC chemokines as CXCR, and the receptors for the XC and CX3C chemokines as XCR and CX3CR, respectively. To date, there are 10 CCRs (CCRs 1 to 10), 7 CXCRs, a single XCR, and a single CX3CR. The numbering is based on the date of deposition of the chemokine receptor sequence within the nucleic acid databases. For orphan receptors, this date refers to the point of identification of the orphan receptors as chemokine receptors and not to the date of initial deposition in the cDNA databases. 

Zamarchi R, Allavena P, Borsetti A, et al. Expression and functional activity of CXCR-4 and CCR-5 chemokine receptors in human thymocytes. Clin Exp Immunol... 

Boisvert WA, Santiago R, Curtiss LK, Terkeltaub RA. A leukocyte homologue of the IL-8 receptor CXCR-2 mediates the accumulation of macrophages in atherosclerotic lesions of LDL receptor-deficient mice. J Clin Invest 1998 101(2) 353-363. 

Ganju RK, Brubaker SA, Meyer J, et al. The alpha-chemokine, stromal cell-derived factor-1 alpha, binds to the transmembrane G-protein-coupled CXCR-4 receptor and activates multiple signal transduction pathways. J Biol Chem 1998 273(36) 23169-23175. 

Milligan G, Wilson S, Lopez-Gimenez JF. The specificity and molecular basis of alphal-adrenoceptor and CXCR chemokine receptor dimerization. J Mol Neurosci 2005 26 161-168. 

Chemokine receptors are a family of G protein-coupled receptors that contain seven transmembrane domains. Chemokine receptors are present on the cell surface membrane of leukocytes. As was the case for chemokines, these receptors are also divided into four subgroups CCR is specific for CC chemokines, CXCR for CXC chemokines, XCR1 for C chemokines and CX3CR1 for CX3C chemokines. The CC chemokine receptor family has eleven members, the CXC chemokine receptor family has seven members, and both the C chemokine receptor family and the CX3C chemokine receptor family have one member each. The signal transduction is mediated via the standard G protein-dependent pathway. 

Curcumin is a hydrophobic polyphenol derived from turmeric the rhizome of the herb Curcuma longa. Traditionally, turmeric and other curcuminoids have been used in therapeutic preparations for various ailments in different parts of the world. Numerous therapeutic effects of curcumin/turmeric have been confirmed by modern scientific research. It is a highly pleiotropic molecule that modulates numerous targets, including the activation of transcription factors (e.g., NF-kB, STAT-3, AP-1, NRF-2, PPR-y, HIF-1), receptors (e.g., HER-2, IL-8, CXCR-4), kinases (e.g., EGFR, ERK, JAK, AAPK), cytokines (e.g., TNF, IL, MIP, MCP), enzymes (e.g., MMP, iNOS, GST, ATPase), and... 

The CXC CKs have been found to have six human receptors CXCRl, CXCR2, CXCR3, CXCR4, CXCRS, and CXCR6. ... 

Mohle R, Bautz F, Rafii S, Moore MA, Brugger W, Kanz L The chemokine receptor CXCR-4 is expressed on CD34+ hematopoietic progenitors and leukemic cells and mediates transendothelial migration induced by stromal cell-derived factor-1. Blood 1998 91 4523-4530. 

Cytokine and chemokine receptors An association between systemic sclerosis and polymorphisms in the CXCR-2 gene has been reported (Renzoni et al., 2000). 

Sehgal A., Keener C., Boynton A. L., et al. (1998) CXCR-4, a chemokine receptor, is overexpressed in and required for proliferationof glioblastoma tumor cells. J Surg Oncol., 69, 99-104. 

Serrati S, Margheri F, Fibbi G, et al. (2008) Endothelial cells and normal breast epithelial cells enhance invasion of breast carcinoma cells by CXCR-4-dependent up-regulation of urokinase-type plasminogen activator receptor (uPAR, CD87) expression. J Pathol 214 545-554... 

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