The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 
 
 

Stromal cell-derived factor-1alpha associates with heparan sulfates through the first beta-strand of the chemokine.

Biological properties of chemokines are believed to be influenced by their association with glycosaminoglycans. Surface plasmon resonance kinetic analysis shows that the CXC chemokine stromal cell-derived factor-1alpha (SDF-1alpha), which binds the CXCR4 receptor, associates with heparin with an affinity constant of 38.4 nM (k(on) = 2.16 x 10(6) M(-1) s(-1) and k(off) = 0.083 x s(-1)). A modified SDF-1alpha (SDF-1 3/6) was generated by combined substitution of the basic cluster of residues Lys(24), His(25), and Lys(27) by Ser. SDF-1 3/6 conserves the global native structure and functional properties of SDF-1alpha, but it is unable to interact with sensor chip-immobilized heparin. The biological relevance of these in vitro findings was investigated. SDF-1alpha was unable to bind in a CXCR4-independent manner on epithelial cells that were treated with heparan sulfate (HS)-degrading enzymes or constitutively lack HS expression. The inability of SDF-1 3/6 to bind to cells underlines the importance of the identified basic cluster for the physiological interactions of SDF-1alpha with HS. Importantly, the amino-terminal domain of SDF-1alpha which is required for binding to, and activation of, CXCR4 remains exposed after binding to HS and is recognized by a neutralizing monoclonal antibody directed against the first residues of the chemokine. Overall, these findings indicate that the Lys(24), His(25), and Lys(27) cluster of residues forms, or is an essential part of, the HS-binding site which is distinct from that required for binding to, and signaling through, CXCR4.[1]

References

  1. Stromal cell-derived factor-1alpha associates with heparan sulfates through the first beta-strand of the chemokine. Amara, A., Lorthioir, O., Valenzuela, A., Magerus, A., Thelen, M., Montes, M., Virelizier, J.L., Delepierre, M., Baleux, F., Lortat-Jacob, H., Arenzana-Seisdedos, F. J. Biol. Chem. (1999) [Pubmed]
 
WikiGenes - Universities