Giuseppetti J M, McCarthy J B, Letourneau P C
Department of Cell Biology, University of Minnesota, Minneapolis 55455.
J Neurosci Res. 1994 Apr 1;37(5):584-95. doi: 10.1002/jnr.490370505.
Cell-surface heparan sulfate proteoglycans (HSPGs) are potential mediators of neuronal cell adhesion, spreading, and neurite outgrowth on various extra-cellular matrix molecules. One possible site of HSPG attachment is a heparin binding domain of fibronectin, which is present in the synthetic peptide FN-C/H II. In this study, HSPGs extracted from embryonic rat spinal cord by detergent were purified by ion-exchange chromatography, gel filtration, and affinity chromatography on an agarose column coupled with FN-C/H II conjugated to ovalbumin (OA). Heparitinase treatment of the iodinated HSPG fraction led to the appearance of a major protein core with a molecular size of 72 kDa, as determined by reducing SDS-PAGE. The intact proteoglycan has a molecular size of approximately 150-165 kDa, containing heparan sulfate glycosaminoglycan chains of about 10-15 kDa. Anti-HSPG antibodies recognized the 72 kDa core protein by immunoblotting, and stained the surface of spinal cord neurons, oligodendrocytes, and a subset of astrocytes. These results identify a cell-surface HSPG that may mediate neuron-substratum or neuron-glia interactions in embryonic central nervous system.
细胞表面硫酸乙酰肝素蛋白聚糖（HSPGs）可能是神经元细胞在各种细胞外基质分子上黏附、铺展和神经突生长的介质。HSPG的一个可能附着位点是纤连蛋白的肝素结合结构域，它存在于合成肽FN-C/H II中。在本研究中，用去污剂从胚胎大鼠脊髓中提取的HSPGs通过离子交换色谱、凝胶过滤以及在与卵清蛋白（OA）偶联的FN-C/H II结合的琼脂糖柱上进行亲和色谱进行纯化。用硫酸乙酰肝素酶处理碘化的HSPG组分后，通过还原SDS-PAGE测定，出现了一个分子量为72 kDa的主要蛋白核心。完整的蛋白聚糖分子量约为150-165 kDa，含有约10-15 kDa的硫酸乙酰肝素糖胺聚糖链。抗HSPG抗体通过免疫印迹识别72 kDa的核心蛋白，并对脊髓神经元、少突胶质细胞和一部分星形胶质细胞的表面进行染色。这些结果鉴定出一种细胞表面HSPG，它可能介导胚胎中枢神经系统中的神经元-基质或神经元-胶质细胞相互作用。
