Figure 10.23 Mucin structure. (A) A schematic representation of a mucoprotein. The VNTR region is highly glycosylated, forcing the molecule into an extended conformation. The Cys-rich domains and the D domain facilitate the polymerization of many such molecules. (B) An example of an oligosaccharide that is bound to the VNTR region of the protein. [Information from A. Varki, R. D. Cummings, J. D. Esko, H. H. Freeze, P. Stanley, C. R. Bertozzi, G. W. Hart, and M. E. Etzler, Essentials of Glycobiology, 2d ed. (Cold Spring Harbor Press, 2009), (Part A) p. 117, Fig. 9.1; (Part B) p. 118, Fig. 9.2.]