Proteoglycans structural features

For proteoglycans such as syndecan-1 and betaglycan, the same core protein can be substituted with both CS and HS chains. Some sequence and structural features of the core protein, such as clusters of flanking acidic amino acids, an adjacent Trp, (Ser-Gly)2 units, or a hydrophobic pocket appear to preferentially direct the addition of HS rather than CS chains, but the relative proportion of HS versus CS chains is also dependent upon the specific expressing cell and growth conditions [21,... 

Features new material on structural heteropolysaccharides and proteoglycans Covers recent techniques for carbohydrate analysis. 

The MMPs are a family of zinc-dependent neutral endopep-tidases that share structural domains but differ in substrate specificity, cellular sources, and inductivity (Table I). All the MMPs are important for remodeling of the extra cellular matrix and share the following functional features (/) they degrade extracellular matrix components, including fibronectin, collagen, elastin, proteoglycans, and laminin, (//) they are secreted in a latent proform and require activation for proteolytic activity, (///) they contain zinc at their active site and need calcium for stability, (/V) they function at neutral pH, and (v) they are inhibited by specific tissue inhibitors of metalloproteinases (TIMPs). 

It has not been easy to devise a satisfactory structure for this Section, since the information available to date falls far short of permitting any classification of proteoglycan-involving disorders. Sectionalization on the basis of clinical presentation of the disorder or the location of the disorder is impossible since it is uncertain which clinical features are the result of primary disorders and indeed whether or not the proteoglycan disorder is a primary effect. The choice of sectionalization is therefore one based on the location of presentation of proteoglycan disorder. 

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