Neame P J, Christner J E, Baker J R
Department Medicine, University of Alabama, Birmingham 35294.
J Biol Chem. 1987 Dec 25;262(36):17768-78.
Cartilage proteoglycan aggregates contain two components (proteoglycan monomer and link protein) which interact with each other and with hyaluronic acid. Data from amino acid sequence analysis are presented that shows that a domain of the proteoglycan, the hyaluronic acid binding region, which interacts with link protein and hyaluronic acid is very similar to link protein in terms of its primary structure. However, the pattern of glycosylation in the hyaluronic acid binding region is different from that found in link protein. After removal of N-linked oligosaccharides, the tryptically prepared hyaluronic acid binding region from rat chondrosarcoma has a mass by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of 43 +/- 2 kDa. The COOH-terminal two-thirds of rat chondrosarcoma link protein, starting at residue 105, has 41.3% identity with a similar region in the hyaluronic acid binding region. We show that, in addition to the hyaluronic acid binding region, proteoglycan contains another region with similarity to the two repeating loop structures in the COOH-terminal two-thirds of link protein. This presumably corresponds to the second globular domain reported in rotary shadowing studies of cartilage proteoglycans. We have deduced the positions of all of the disulfide bonds in the hyaluronic acid binding region and find them to be in the same positions as would be expected from comparison of these sequences with link protein.
软骨蛋白聚糖聚集体包含两种相互作用且与透明质酸相互作用的成分（蛋白聚糖单体和连接蛋白）。本文提供了氨基酸序列分析数据，结果表明蛋白聚糖的一个结构域，即与连接蛋白和透明质酸相互作用的透明质酸结合区域，在一级结构上与连接蛋白非常相似。然而，透明质酸结合区域的糖基化模式与连接蛋白中的不同。去除N - 连接寡糖后，经胰蛋白酶处理的大鼠软骨肉瘤透明质酸结合区域通过十二烷基硫酸钠 - 聚丙烯酰胺凝胶电泳分析的质量为43±2 kDa。大鼠软骨肉瘤连接蛋白从第105位残基开始的COOH末端三分之二与透明质酸结合区域的类似区域具有41.3%的同一性。我们发现，除了透明质酸结合区域外，蛋白聚糖还包含另一个与连接蛋白COOH末端三分之二的两个重复环结构相似的区域。这大概对应于软骨蛋白聚糖旋转阴影研究中报道的第二个球状结构域。我们已经推导了透明质酸结合区域中所有二硫键的位置，发现它们与通过将这些序列与连接蛋白比较所预期的位置相同。
