Preparation and Utility of Neoproteoglycan Probes in Analyses of Interaction with Glycosaminoglycan-Binding Proteins

Proteoglycans have been attracting increasing biological interest because of their specific signaling roles or modulatory functions in important cellular events, for example, growth factor–receptor interaction and signaling, viral infection, extracellular matrix assembly, and neurite outgrowth and plasticity. Such functions are exhibited mostly by glycosaminoglycanbinding proteins (lectins or receptors) that recognize repeating disaccharide units with microheterogeneities in the sugar residues and the negative charges. There is a need for a detailed study in the specificity of lectins to glycoconjugates, because certain multispecificities may call into question the validity of the lectins when used as carbohydrate-specific probes. This chapter discusses two types of neoproteoglycan probes—one is used to immobilize glycosaminoglycans or polysaccharides effectively on solid substrates and the other is a biotin- or peroxidase-labeled neoproteoglycan probe that is used to detect binding with high sensitivity.