Schwarz K, Breuer B, Kresse H
Institute of Physiological Chemistry and Pathobiochemistry, University of Munster, Federal Republic of Germany.
J Biol Chem. 1990 Dec 15;265(35):22023-8.
Human osteosarcoma cells express a 78-kDa proteoglycan core protein to which an asparagine-bound oligosaccharide, O-glycosidically linked oligosaccharides and probably only a single chondroitin 6-sulfate chain of 29-kDa are bound. Prior to O-glycosylation, the N-glycosylated core protein exhibits a mass of 83 kDa. Upon digestion of the secreted proteoglycan with chondroitin ABC lyase a mature core protein with an apparent molecular mass of 106 kDa is obtained. Smaller amounts of core proteins of 101 and 115 kDa can be detected occasionally. The glycosaminoglycan composition and the relative molecular mass of the glycosaminoglycan chain distinguish this proteoglycan, tentatively named proteoglycan 100 (PG-100), from biglycan (small proteoglycan I) and decorin (small proteoglycan II) which are also expressed by osteosarcoma cells. An antiserum against PG-100 shows partial cross-reactivity with decorin, but in contrast to the latter proteoglycan it does not bind to type I collagen fibrils. PG-100 is not a unique product of osteosarcoma cells. It has also been found in the secretions of human skin fibroblasts.
人骨肉瘤细胞表达一种78 kDa的蛋白聚糖核心蛋白，其上结合有一个与天冬酰胺相连的寡糖、O-糖苷键连接的寡糖，可能还仅结合一条29 kDa的硫酸软骨素6-硫酸酯链。在进行O-糖基化之前，N-糖基化的核心蛋白质量为83 kDa。用硫酸软骨素ABC裂解酶消化分泌的蛋白聚糖后，可得到一种表观分子量为106 kDa的成熟核心蛋白。偶尔也能检测到少量101 kDa和115 kDa的核心蛋白。这种蛋白聚糖（暂命名为蛋白聚糖100，即PG-100）的糖胺聚糖组成和糖胺聚糖链的相对分子量，与骨肉瘤细胞也表达的双糖链蛋白聚糖（小蛋白聚糖I）和核心蛋白聚糖（小蛋白聚糖II）有所不同。抗PG-100抗血清与核心蛋白聚糖有部分交叉反应，但与后者不同的是，它不与I型胶原纤维结合。PG-100并非骨肉瘤细胞的独特产物，在人皮肤成纤维细胞的分泌物中也有发现。
