Yamada H, Watanabe K, Shimonaka M, Yamaguchi Y
Cancer Research Center, La Jolla Cancer Research Foundation, California 92037.
J Biol Chem. 1994 Apr 1;269(13):10119-26.
To clone novel brain proteoglycans, we employed a strategy based on polyclonal antisera that recognize multiple proteoglycan core proteins. By using an antiserum raised against a fraction enriched for proteoglycans, we isolated three groups of cDNAs from a bovine brain lambda gt11 library. One of the cDNA groups has been fully sequenced and shown to encode a novel proteoglycan core protein of the aggrecan/versican family. This proteoglycan, named brevican, carries chondroitin sulfate chains, and, like other members of the family, contains a hyaluronic acid-binding domain in its N-terminal region, an epidermal growth factor-like repeat, a lectin-like and a complement regulatory protein-like domains in its C-terminal region. In contrast, the central region of brevican is much shorter than that of aggrecan, versican, or neurocan, and shows little homology with these proteoglycans. Brevican core protein exists as a 145 kDa full-length form and a 80 kDa N terminally truncated form. A significant amount of brevican devoid of any glycosaminoglycan chains is present in the brain, indicating that brevican is a "part-time" proteoglycan. Northern blot analysis reveals that a single 3.3-kilobase brevican transcript is present predominantly in the brain, and that it is expressed in primary cerebellar astrocytes but not in neurons.
为了克隆新型脑蛋白聚糖，我们采用了一种基于能识别多种蛋白聚糖核心蛋白的多克隆抗血清的策略。通过使用针对富含蛋白聚糖的组分产生的抗血清，我们从牛脑λgt11文库中分离出三组cDNA。其中一组cDNA已被完全测序，并显示编码聚集蛋白聚糖/多功能蛋白聚糖家族的一种新型蛋白聚糖核心蛋白。这种蛋白聚糖名为短蛋白聚糖，带有硫酸软骨素链，并且与该家族的其他成员一样，在其N端区域含有一个透明质酸结合结构域，在其C端区域含有一个表皮生长因子样重复序列、一个凝集素样结构域和一个补体调节蛋白样结构域。相比之下，短蛋白聚糖的中央区域比聚集蛋白聚糖、多功能蛋白聚糖或神经蛋白聚糖的中央区域短得多，并且与这些蛋白聚糖几乎没有同源性。短蛋白聚糖核心蛋白以145 kDa的全长形式和80 kDa的N端截短形式存在。脑中存在大量不含任何糖胺聚糖链的短蛋白聚糖，这表明短蛋白聚糖是一种“兼职”蛋白聚糖。Northern印迹分析显示，一个单一的3.3千碱基短蛋白聚糖转录本主要存在于脑中，并且它在原代小脑星形胶质细胞中表达，但在神经元中不表达。
