Molecular basis of interaction between NG2 proteoglycan and galectin-3
Article first published online: 19 DEC 2005
Copyright © 2005 Wiley-Liss, Inc.
Journal of Cellular Biochemistry
Volume 98, Issue 1, pages 115–127, 1 May 2006
How to Cite
Wen, Y., Makagiansar, I. T., Fukushi, J.-i., Liu, F.-T., Fukuda, M. N. and Stallcup, W. B. (2006), Molecular basis of interaction between NG2 proteoglycan and galectin-3. J. Cell. Biochem., 98: 115–127. doi: 10.1002/jcb.20768
- Issue published online: 6 APR 2006
- Article first published online: 19 DEC 2005
- Manuscript Accepted: 16 NOV 2005
- Manuscript Received: 19 OCT 2005
- National Institutes of Health (to W.B.S.). Grant Numbers: RO1 CA95287, PO1 HD25938
- carbohydrate-dependent protein–protein interaction;
Previous work has demonstrated the ability of the NG2 proteoglycan, a component of microvascular pericytes, to stimulate endothelial cell motility and morphogenesis. This function of NG2 depends on formation of a complex with galectin-3 and α3β1 integrin to stimulate integrin-mediated transmembrane signaling. In addition, the co-expression of galectin-3 and NG2 in A375 melanoma cells suggests that the malignant properties of these cells may be affected by interaction between the two molecules. Here, we extend the theme of co-expression and interaction of NG2 and galectin-3 to human glioma cells. We also establish a molecular basis for the NG2/galectin-3 interaction. The C-terminal carbohydrate recognition domain of galectin-3 is responsible for binding to the NG2 core protein. Within the NG2 extracellular domain, the membrane-proximal D3 segment of the proteoglycan contains the primary binding site for interaction with galectin-3. The interaction between galectin-3 and NG2 is a carbohydrate-dependent one mediated by N-linked rather than O-linked oligosaccharides within the D3 domain of the NG2 core protein. These studies establish a foundation for attempts to reduce the aggressive properties of tumor cells by disrupting the NG2/galectin-3 interaction. J. Cell. Biochem. 98: 115–127, 2006. © 2005 Wiley-Liss, Inc.