Proteoglycans decorin

Leucine-rich repeats represent binding motifs found in a wide variety of both plant and mammalian proteins (Kobe and Kajava, 2001). These are involved in a multitude of protein-protein interactions. The sequence of porcine ribonuclease inhibitor, for example, displays a leucine-rich repeat (LRR) of length 27-29 residues that occurs 15 times in tandem (Fig. 9). Likewise, the family of small leucine-rich proteoglycans that includes biglycan, decorin, epiphycan, fibromodulin, keratocan, and lumican... 

Trask, B. C., Trask, T. M., Broekelmann, T., and Mecham, R. P. (2000). The microfibrillar proteins MAGP-1 and fibrillin-1 form a ternary complex with the chondroi-tin sulfate proteoglycan decorin. Mol. Biol. Cell 11, 1499-1507. 

Decorin is a small, leucine-rich proteoglycan and one of the many extracellular matrix (ECM) compounds. It interacts closely with the D and E bands of type 1 collagen and increases collagen s tensile strength.39,40 In rats with subcutaneously implanted devices, we found that the decorin was highly expressed at the middle and later stages of the foreign body reaction.17... 

Hildebrand, A., Romans, M., Rasmussen, L.M., Heinegard, D., Twardzik, D.R., Border, W.A., and Ruoslahti, E. 1994. Interaction of the small interstitial proteoglycans biglycan, decorin and fibromodulin with transforming growth factor beta. Biochem. J. 302 527-534. 

Figure 2.35. Comparison between proteoglycan structures. The diagram illustrates structures of decorin (one glycosaminoglycan side chain), biglycan (two gly-cosaminoglycan side chains), proteoglycan-Lb, fibromodulin, and lumican. Also shown is the specific binding of decorin to the d and e bands on collagen fibrils.

The hyaluronan content of skin has been estimated to be between 0.03% and 0.09%, and dermatan sulfate represents 30 to 40% of dermal proteoglycans. The GAG content is reported to decrease with respect to the amount of protein with increased age, and a recent report suggests that there is a decrease in the proportion of versican and an increase in decorin with increased age, which is associated with the appearance of a small PG that may be a catabolic fragment of decorin. 

Moses J, Oldberg A, Eklund E, Fransson LA. Biosynthesis of the proteoglycan decorin - identification of intermediates in galac-tosaminoglycan assembly. Eur. J. Biochem. 1997 248(3) 767- 84. 

The marked alteration of biglycans and decorin during the development of fibrosis su ests that these proteoglycans have a regulating role in this process (Westergren-Thorsson etal., 1993). 

Yamaguchi Y, Mann DM, Ruoslahti E. 1990. Negative regulation of TGF p by the proteoglycan decorin. Nature 346 281-84... 

We have also achieved suppression of scarring in the CNS using decorin, a small dermatan sulphate proteoglycan, which is a more universal antagonist of the TGF-P... 

The proteoglycans in this family, which includes decorin, biglycan, lumican, and fibromodulin, are major components of the interstitial matrix produced by fibroblasts and other cells. The core proteins are small (37-45 kDa) and have several leucine-rich motifs [112] with similarity to the LH-CG receptor, thyrotropin receptor, and Drosophila proteins chaoptin and toll. Core proteins of this family characteristically undergo proteolytic processing following synthesis, with removal of an additional small peptide from the N-terminus. 

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