Proteoglycan with hyaluronate, interaction

Proteoglycan aggregates are typically found in the extracellular matrix of connective tissue. The noncovalent attachment of each proteoglycan to hyaluronic acid via the core protein is mediated by two linker proteins (not shown). Proteoglycans interact with numerous fibrous proteins in the extracellular matrix such as collagen, elastin, and fibronectin (a glycoprotein involved in cell adhesion). 

Melching LI, Roughley PJ. Studies on the interaction of newly secreted proteoglycan subunits with hyaluronate in human articular cartilage. Biochim Biophys Acta Gen Subj 1990 1035 20-28. 

The electric birefringence technique has been shown to be suitable for investigations of cartilage proteoglycans and their interactions with hyaluronic acid. ... 

Hardingham, T. E., Muir, H. The specific interaction of hyaluronic acid with cartilage proteoglycans. Biochim. Biophys. Acta 279, 401 (1972)... 

Schematic representation of cartilage proteoglycan. The monomers, consisting of glycosaminoglycan chains linked to a core protein by covalent linkage, extend laterally at intervals from opposite sides of a very long filament of hyaluronate. The interaction between the core protein and hyaluronate is noncovalent and is aided by the link protein. The entire structure is highly hydrated and occupies a large volume. [Reproduced with permission from W. J. Lennarz, The Biochemistry of Glycoproteins and Proteoglycans, Plenum Press, New York, 1980].

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