Biotinylated CXCL12 Protein (OPCB00014)

• Product Number: OPCB00014
• Name: Biotinylated CXCL12 Protein (OPCB00014)
• Molecular Weight: 10.4 kDa
• Conjugation: Biotin
• NCBI Gene Id: 6387
• Purity: > 97% as determined by SDS-PAGE
• Source: E. coli
• Gene Full Name: chemokine (C-X-C motif) ligand 12
• Alias Symbols: IRH, PBSF, SDF1, TLSF, TPAR1, SCYB12
• Product Format: Lyophilized
• Reference: 1. "Structure and chromosomal localization of the human stromal cell-derived factor 1 (SDF1) gene."
  Shirozu M., Nakano T., Inazawa J., Tashiro K., Tada H., Shinohara T., Honjo T.
  Genomics 28:495-500(1995)
  2. "Identification and expression of novel isoforms of human stromal cell-derived factor 1."
  Yu L., Cecil J., Peng S.B., Schrementi J., Kovacevic S., Paul D., Su E.W., Wang J.
  Gene 374:174-179(2006)
  3. "Nucleotide sequence of hIRH, human intercrine reduced in hepatomas."
  Begum N.A., Barnard G.F.
  Submitted (JAN-1995) to the EMBL/GenBank/DDBJ databases
  4. "Polymorphism study of cell-derived factor 1 (SDF1) gene and their correlation with HIV infection in a Chinese cohort."
  Zhao X., Zhang H., Lee S., Wong K., Zheng B.
  Submitted (DEC-2004) to the EMBL/GenBank/DDBJ databases
• Description of Target: Chemoattractant active on T-lymphocytes, monocytes, but not neutrophils. Activates the C-X-C chemokine receptor CXCR4 to induce a rapid and transient rise in the level of intracellular calcium ions and chemotaxis. Also binds to another C-X-C chemokine receptor CXCR7, which activates the beta-arrestin pathway and acts as a scavenger receptor for SDF-1. SDF-1-beta(3-72) and SDF-1-alpha(3-67) show a reduced chemotactic activity. Binding to cell surface proteoglycans seems to inhibit formation of SDF-1-alpha(3-67) and thus to preserve activity on local sites. Acts as a positive regulator of monocyte migration and a negative regulator of monocyte adhesion via the LYN kinase. Stimulates migration of monocytes and T-lymphocytes through its receptors, CXCR4 and CXCR7, and decreases monocyte adherence to surfaces coated with ICAM-1, a ligand for beta-2 integrins. SDF1A/CXCR4 signaling axis inhibits beta-2 integrin LFA-1 mediated adhesion of monocytes to ICAM-1 through LYN kinase. Inhibits CXCR4-mediated infection by T-cell line-adapted HIV-1. Plays a protective role after myocardial infarction. Induces down-regulation and internalization of CXCR7 expressed in various cells. Has several critical functions during embryonic development; required for B-cell lymphopoiesis, myelopoiesis in bone marrow and heart ventricular septum formation.
  Biotinylated CXCL12 is made using the enzymatic method, which has several advantages over chemical biotinylation methods. The attachment of biotin at a specific lysine residue within the C-terminal avi tag sequence is nearly 100% complete, and leads to a modified chemokine with functionalities comparable to those of the unmodified CXCL12 in calcium flux and migration assay. Combining with avidin analogues conjugated to various fluorescent labels, biotinylated CXCL12 is useful in studies on receptor identification, distribution, chemokine binding, and other cellular assays. They serve as great tools in visualization and quantification, and replace the needs for radioactively labeled chemokines.
• Reconstitution and Storage: Spin tube prior to resuspending. Reconstitute at 100 ug/mL in sterile water (recommended). Use immediately after reconstitution. Store at -20°C to -70°C for 12 months after date of receipt. After reconstitution, can be stored at -20°C to -70°C for at least one month under sterile conditions. Avoid repeated freeze/thaw cycles.
• Additional Information: Extinction Coefficient: 14,180 M-1 cm-1
  Endotoxin Level: <0.01 EU per 1 ug of the protein by the LAL method
• Biological Activity: EC50 = 0.5-0.9nM determined by Calcium Flux with human CXCR4 in U937 cells
• Uniprot ID: P48061
• Gene Symbol: CXCL12
• Application: CA, CM, IF
• Image 1: CXCR4 Surface Detection
  
  CXCR4 Surface Detection Confocal microscopy images of surface stained U937 cells with SDF-1 alpha-biotin conjugated to streptavidin-Cy3.
• Image 2: Dose Dependent Ca2+ Flux
  
  Dose Dependent Ca2+ Flux HEK293 cells expressing CXCR4 were stimulated with SDF-1 alpha-biotinylated. Calcium flux was measured with calcium dye from Molecular Devices. A dose response curve was obtained and an EC50 of 3.5nM was recorded.