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Published on: June 23, 2014
细胞质蛋白特别结合核定位信号的细胞质蛋白是核进口的受体
1Department of Cell, Molecular and Structural Biology, Northwestern University Medical School, Chicago, Illinois 60611.
Cell
|September 6, 1991
概括
研究人员确定了两种牛红细胞蛋白质,它们与核定位序列 (NLS) 结合. 这些NLS结合蛋白作为NEM敏感受体,在无细胞系统中促进核进口.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 蛋白质生物化学 蛋白质生物化学
背景情况:
- 核进口是调节基因表达和细胞功能的关键细胞过程.
- 核定位序列 (NLS) 引导蛋白质进入核.
- 已知细胞系因子调解核进口,但它们的具体作用尚未完全阐明.
研究的目的:
- 为了识别和描述涉及核进口的蛋白质.
- 研究NLS结合蛋白在中介核蛋白传输中的作用.
- 为了确定核进口因子对N-乙烯胺胺 (NEM) 的敏感性.
主要方法:
- 从牛红细胞中净化54和56kd的多.
- 在体外核进口试验中,使用透细胞系统进行核进口试验.
- 通过纯化蛋白质评估NLS结合活性和进口刺激.
- 对净化蛋白质和细胞质因子的NEM敏感性的分析.
主要成果:
- 净化了两种主要的多 (54和56kd),它们特别结合SV40大T抗原NLS.
- 纯化的NLS结合蛋白在无细胞系统中增强了含有NLS的光蛋白的核进口2到3倍.
- 进口刺激是可和的,依赖于细胞质,并由NEM敏感受体介导.
- 在不影响NLS结合的情况下,NEM处理使净化蛋白质的进口刺激能力失活.
结论:
- 纯化的54和56kd牛红细胞蛋白作为核进口的NEM敏感受体起作用.
- 这些NLS结合蛋白对于调解蛋白质进入细胞核的运输至关重要.
- 为了有效的体外核进口,还需要额外的NEM敏感和NEM不敏感的细胞质因子.
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