Proteoglycan aggregated

Figure 48-6. Dark field electron micrograph of a proteoglycan aggregate in which the proteoglycan subunits and filamentous backbone are particularly well extended. (Reproduced, with permission, from Rosenberg L, Heilman W, Kleinschmidt AK Electron microscopic studies of proteoglycan aggregates from bovine articular cartilage. J Biol Chem 1975 250 1877.)...

Cuervo, L. A., Pita, J. C., Howell, D. S. Inhibition of calcium phosphate mineral growth by proteoglycan aggregate fractions in a synthetic lymph. Calc. Tiss. Res. 13, 1 (1973)... 

KSII is found in loose connective tissue proteoglycan aggregates with chondroitin sulfate. KS I is found in cornea. 

Figure 4-16 (A) Dark field electron micrograph of a proteoglycan aggregate from bovine articular cartilage (from bearing surfaces of joints). Courtesy of Joseph A. Buckwalter. The filamentous backbone consists of hyaluronic acid, as in (B). The proteoglycan subunits extend from the backbone. From Rosenberg.149...

A low molecular weight protein, called link protein is also a component of proteoglycan aggregates. Link protein appears to bind simultaneously to hyaluronate and to the hyaluronic acid binding region of core protein, and stabilizes the bond between proteoglycan... 

Heinegard and Hascall made a remarkable observation. They found that in proteoglycan aggregates, the polysaccharide attachment region of core protein was readily and selectively degraded by trypsin ( 18 ). As... 

Figure 3.26. Diagram illustrating the relationship between hyaluronic acid (hyaluronan), link protein, and proteoglycans in proteoglycan aggregates.

Figure 9.14 Proteoglycan aggregate found in cartilage. C and N are C and N termini of the core protein. Long wavy lines represent chondroitin sulfate, whereas the short lines represent keratan sulfate. All are linkied to the core protein via the O-serine linkage, except for a few oligosaccharide chains near the N terminus of the core protein. LP is link protein, and HA is hyaluronic acid. (Reproduced by permission from Hascall V. Introduction. Functions of the Proteoglycans, Ciba Foundation Symposium 124. New York Wiley Sons, 1986, p. 2.)...

Link protein strengthens the noncovalent interaction between the core protein and hyaluronic acid in proteoglycan aggregates. 

Fig. 5-23 A diagrammatic representation of part of a proteoglycan aggregate from cartilage.

Fig. 5-24 Portion of a proteoglycan aggregate showing the bottlebrush-like structure.

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