Clark V M
Jules Stein Eye Institute, UCLA Center for Health Sciences 90024-1771.
Invest Ophthalmol Vis Sci. 1989 Jul;30(7):1542-7.
Glycoproteins were metabolically labeled with 3H-fucose in cultured RPE cells from RCS rdy-p+ and Long Evans rats. 3H-labeled glycoproteins associated with a plasma membrane-enriched subcellular fraction were separated by two-dimensional gel electrophoresis. Relative incorporation of 3H-fucose into high molecular weight cell surface glycoproteins (Mr of 128,000-183,000) was measured by quantitative autoradiography and densitometry. The results of these experiments show that 3H-fucose incorporation into four glycoproteins (Mr of 183,000, 175,000, 164,000 and 156,000) was reduced by 30-50% in the dystrophic RPE as compared to the normal cells. This reduction was not due to an absence of the protein core of glycoproteins on the dystrophic RPE cell surface; when RPE cells were labeled with 3H-leucine prior to analysis, no reduction in label was found in the dystrophic RPE as compared to normal. Therefore, the results of this study suggest that the RCS rat RPE processes the oligosaccharide portion of some cell surface glycoproteins differently than normal rat RPE.
用3H-岩藻糖对来自RCS rdy-p+大鼠和Long Evans大鼠的培养视网膜色素上皮（RPE）细胞中的糖蛋白进行代谢标记。通过二维凝胶电泳分离与富含质膜的亚细胞组分相关的3H标记糖蛋白。通过定量放射自显影和光密度测定法测量3H-岩藻糖掺入高分子量细胞表面糖蛋白（分子量为128,000 - 183,000）中的相对掺入量。这些实验结果表明，与正常细胞相比，营养不良的RPE细胞中，3H-岩藻糖掺入四种糖蛋白（分子量分别为183,000、175,000、164,000和156,000）的量减少了30 - 50%。这种减少并不是由于营养不良的RPE细胞表面糖蛋白的蛋白质核心缺失；在分析前用3H-亮氨酸标记RPE细胞时，与正常细胞相比，营养不良的RPE细胞中标记没有减少。因此，本研究结果表明，RCS大鼠的RPE处理某些细胞表面糖蛋白的寡糖部分的方式与正常大鼠的RPE不同。
