在S. cerevisiae中的信号识别粒子
1Department of Biochemistry and Biophysics, University of California, Medical School, San Francisco 94143-0448.
Cell
|October 4, 1991
概括
研究人员确定了Saccharomyces cerevisiae信号识别粒子 (SRP),这对蛋白质转位至关重要. 缺乏SRP的酵母细胞显示蛋白质向受损,尽管生长并非致命,表明部分绕过机制.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 信号识别粒子 (SRP) 途径对于将蛋白质准到真核细胞内 (ER) 膜至关重要.
- 以前对酵母和细菌的研究尚未完全阐明SRP依赖蛋白向通路的组成部分.
研究的目的:
- 识别和描述信号识别粒子 (SRP) 的Saccharomyces cerevisiae同类物.
- 为了研究酵母SRP在ER膜中蛋白质转位中的体内功能.
主要方法:
- 识别Saccharomyces cerevisiae的SRP组成部分,包括SRP54p和scR1.
- 在体内分析缺乏SRP的酵母细胞生长和蛋白质转位缺陷.
主要成果:
- 细菌菌素 (Saccharomyces cerevisiae SRP) 是一种含有SRP54p和scR1.1的16S粒子.
- 编码scR1和SRP54p的基因是不必要的,但SRP缺陷的细胞表现出不良的生长.
- 在缺乏SRP的细胞中,蛋白质穿过ER膜的转位受损,不同蛋白质的缺陷不同.
结论:
- 酵母SRP在蛋白质转移中发挥着至关重要的作用,类似于其哺乳动物对应物.
- 在体内部分绕过SRP功能和可变转位缺陷可能解释了为什么SRP通路组件以前没有在酵母和细菌中被确定.
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