Isolation and characterization of rat skeletal muscle proteoglycan decorin and comparison with the human fibroblast decorin.

1. The extracellular matrix (ECM) of rat skeletal muscle contains several proteoglycans (PGs). The more abundant correspond to a chondroitin/dermatan sulfate PG or decorin. 2. Decorin isolated from rat skeletal muscle ECM has a smaller molecular size than human fibroblast decorin. 3. The difference in size is mainly due to the glycosaminoglycan (GAG) chain length rather than the core protein size. 4. Peptide analysis of trypsin treated decorins shows at least three peptides with the same electrophoretic mobility.