抓病的蛋白含有酸丁氨基醇糖脂蛋白
N Stahl1, D R Borchelt, K Hsiao
1Department of Neurology, University of California, San Francisco 94143.
Cell
|October 23, 1987
概括
细胞质蛋白 (PrPC) 通过酸丁氨基醇糖脂通过细胞表面固定. 这一发现揭示了质蛋白结构和细胞膜相互作用.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 神经科学是一个神经科学.
背景情况:
- 细胞蛋白 (PrPC) 和尖病蛋白 (PrPSc) 分享一个共同的基因,但表现出不同的特性.
- 假设翻译后的修改会导致这些不同的特性.
研究的目的:
- 为了研究PrPC和PrPSc差异的分子基础.
- 为了确定PrPC与细胞表面的固机制.
主要方法:
- 凝净化PrP 27-30 (由PrPSc衍生而来的).
- 使用生物化学分析识别甘油脂成分.
- 用酸氨基醇特异性脂酶C (PIPLC) 进行酶性消化.
- 使用特定抗血清的免疫学测定.
主要成果:
- 在PrPC和PrP 27-30上都发现了一种酸基脂.
- 乙醇胺,myo-inositol,酸和酸被证实是葡萄糖脂的组成部分.
- PIPLC治疗释放了结合的酸,并促进了特定的抗血清反应.
- 在PIPLC治疗中,PrPC从培养的哺乳动物细胞释放到介质中.
结论:
- PrPC是通过酸氨基醇糖脂质固定在细胞表面.
- 这种甘油脂结合是PrPC细胞表面局部化的关键特征.
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