Chain Chondroitin sulfate

As noted above, in the intact aggregate (19), or in complexes formed between hyaluronate and proteoglycan monomers with intact chondroitin sulfate chains, the minimum spacing between proteoglycan monomers is 250 A. These observations indicate that the spacing of proteoglycan monomers on hyaluronate is determined by the lengths of chondroitin sulfate chains. 

Syndecan consists of a core protein that is inserted through the cell membrane and contains both heparan sulfate and chondroitin sulfate chains. Glypican is covalently linked to the head group of membrane phospholipids in the plasma membrane and contains only heparan sulfate side chains. 

Kanayama N, Maehara K, Suzuki M, Fujise Y, Terao T. The role of chondroitin sulfate chains of urinary trypsin inhibitor in inhibition of LPS-induced increase of cytosolic free Ca2+ in HL60 cells and HUVEC cells. Biochem Biophys Res Commun 1997 238 560-564. 

Mizon C, Mairie C, Balduyck M, Hachulla E, Mizon J. The chondroitin sulfate chain of bikunin-containing proteins in the inter-alpha-inhibitor family increases in size in inflammatory diseases. Eur J Biochem 2001 268 2717-2724. 

Bone sialoprotein has a molecular weight of about 25,000. About 20% of the weight of the protein is sialic acid, an acidic sugar. The protein may aid in the formation of collagen fibers prior to the deposit of minerals. It is thought that osteonectin promotes the adhesion of osteoblasts to unmineralized surfaces. The protein component of the protein-chondroitin sulfate complex of bone has a molecular weight of 45,000, whereas the molecular weight of each of the associated chondroitin sulfate chains is 40,000. The complex, in bone, contains only one or two chains of chondroitin sulfate. 

Invariant chain is a transmembrane protein which temporarily associates in the ER and the Golgi apparatus with class II gene products of the major histocompatibility complex. A small portion of the invariant chain molecules carry a chondroitin sulfate chain [186]. The proteoglycan form of the invariant chain was shown to play a role in the stimulation ofT cell response [187]. 

Chondroitin sulfate chains have been likened to a large fishnet, passing small molecules through their matrix but excluding... 

In breast cancer cells, increased numbers of chondroitin sulfate chains linked to P-selectin enhanced the attachment of cancer cells to vascular endothelial cells forcing tissue invasion of tumor cells (36). Increased levels of chondroitin sulfates were also found in melanoma (37) and ovarian carcinoma (38) and enhanced the mitogenic effect of platelet-derived growth factor-BB on fibrosarcoma cells (39). Chondroitin sulfates have a role in tissue remodeling, tumor progression, and metastasis (40). 

Effect of chondroitinase ABC. This enzyme (chondroitin ABC lyase, EC A.2.2.A.) also depolymerizes the hyaluronic acid backbone of aggregate. In addition, it can degrade chondroitin sulfate chains of monomer, but not its keratan sulfate chains. 

To 0.1% solution of proteoglycan 0.005U of the enzyme was added. As shown in Figure 9, the specific fluidity of the solution, either in the presence of or in the absence of hyaluronic acid. Increased in two stages. The first linear Increase may indicate the break down of hyaluronic acid backbone. Then upward Increase which follows may be due to the shortening or removal of chondroitin sulfate chains of monomeric proteoglycan. 

J.F. Piai, A.F. Rubira, E.C. Muniz, Self-assembly of a swollen chito-san/chondroitin sulfate hydrogel by outward diffusion of the chondroitin sulfate chains, Acta Biomater. 5 (7) (2009) 2601-2609. 

We recently found that the various Pasteurella GAG synthases can also use non-cognate acceptor molecules. In the example shown in Fig. 2, we added a HA chain onto an existing chondroitin sulfate chain using pmHAS (P). This particular family of hybrid molecules may be useful as artificial proteoglycans for tissue engineering that do not contain the protein component of the natural cartilage proteoglycans. 

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