Roughley P J, White R J, Magny M C, Liu J, Pearce R H, Mort J S
Genetics Unit, Shriners Hospital for Crippled Children, McGill University, Montreal, Canada.
Biochem J. 1993 Oct 15;295 ( Pt 2)(Pt 2):421-6. doi: 10.1042/bj2950421.
Polyclonal anti-peptide antibodies were raised to the C-terminal regions of human biglycan and decorin. These antibodies were used in immunoblotting to study structural variations with age in the proteoglycan core proteins present in extracts of human articular cartilage and intervertebral disc. Three forms of the biglycan core protein were identified. The largest form was detected only after chondroitinase treatment and represents the proteoglycan form of the molecule from which the glycosaminoglycan chains have been removed. However, chondroitinase treatment did not alter the electrophoretic mobility of the two smaller proteins, which appear to represent non-proteoglycan forms of the molecule, resulting either from a failure to substitute the intact proteoglycan core protein with glycosaminoglycan chains during its synthesis or from proteolytic processing of the intact proteoglycan causing removal of the N-terminal region bearing the glycosaminoglycan chains. The non-proteoglycan forms constituted a minor proportion of biglycan in the newborn, but were the major components in the adult. A similar trend was seen in both articular cartilage and intervertebral disc. In comparison, decorin appears to exist predominantly as a proteoglycan at all ages, with two core protein sizes being present after chondroitinase treatment. Non-proteoglycan forms were detected in the adult, but they were always a minor constituent.
制备了针对人双糖链蛋白聚糖和核心蛋白聚糖C末端区域的多克隆抗肽抗体。这些抗体用于免疫印迹，以研究人关节软骨和椎间盘提取物中蛋白聚糖核心蛋白随年龄的结构变化。鉴定出了双糖链蛋白聚糖核心蛋白的三种形式。最大的形式仅在软骨素酶处理后检测到，代表已去除糖胺聚糖链的分子的蛋白聚糖形式。然而，软骨素酶处理并未改变两种较小蛋白质的电泳迁移率，这两种较小的蛋白质似乎代表分子的非蛋白聚糖形式，这可能是由于在合成过程中完整的蛋白聚糖核心蛋白未能被糖胺聚糖链取代，或者是由于完整蛋白聚糖的蛋白水解加工导致带有糖胺聚糖链的N末端区域被去除。非蛋白聚糖形式在新生儿的双糖链蛋白聚糖中占比很小，但在成年人中是主要成分。在关节软骨和椎间盘中都观察到了类似的趋势。相比之下，核心蛋白聚糖在所有年龄段似乎主要以蛋白聚糖的形式存在，软骨素酶处理后存在两种核心蛋白大小。在成年人中检测到了非蛋白聚糖形式，但它们始终是次要成分。
