Fibronectin cell-binding sites

The binding of integrins to certain ligands is mediated by a short amino acid sequence. Thus, the binding site for fibronectin is confined to a sequence of four amino acid residues, Arg-Gly-Asp-Ser (RGDS) (R7). Synthetic peptides containing the RGDS sequence prevented adhesion of cells to fibronectin (B4, R7) and also inhibited metastasis formation in animal models (B4, R7). 

Elices, M. J., Osborn, L., Takada, Y., Crouse, C., Luhowskyj, S., Hemler, M. E., and Lobb, R. R. (1990). VCAM-1 on activated endothelium interacts with the leukocyte integrin VLA-4 at a site distinct from the VLA-4/fibronectin binding site. Cell 60,577-584. 

Fibronectin is a large glycoprotein normally present in blood and connective tissue that is made up of a number of different domains serving as binding sites to various cells via specific integrin receptors... 

Sechler, J. L., Rao, H., Cumiskey, A. M., Vega-Colon, I., Smith, M. S., Murata, T., and Schwarzbauer, J. E. (2001). A novel fibronectin binding site required for fibronec-tin fibril growth during matrix assembly./ Cell Biol. 154, 1081-1088. 

Pretzlaff, R. K., Xue, V. W., Rowin, M. E. (2000). Sialidase treatment exposes the pi—integrin active ligand binding site on HL60 cells and increases binding to fibronectin. Cell Adhes. Commun., 7,491-500. 

Fibronectins are abundant multladhesive matrix proteins that play a key role In migration and cellular differentiation. They contain binding sites for Integrlns and ECM components (collagens, proteoglycans) and can thus attach cells to the matrix (see Figure 6-23). 

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