促进核运输素H1和其他小核友蛋白质的核运输
1Department of Biology, University of Rochester, New York 14627.
Cell
|March 23, 1990
概括
小蛋白质可以进入细胞核,但含有核定位信号 (NLS) 的蛋白质依赖于受体介导的传输,而不是扩散. 冷却或能量耗尽停止了这一过程,揭示了受监管的核进口机制.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 核进口对细胞功能至关重要.
- 核定位信号 (NLS) 介导蛋白质运输到核中.
- 控制小蛋白与含有NLS蛋白的运输机制尚未完全理解.
研究的目的:
- 研究小型非核蛋白和含有NLS的蛋白质进入细胞核中的运输机制.
- 为了确定细胞能量状态和温度对核进口的作用.
- 为了阐明由素H1和NLS-联体所使用的特定途径.
主要方法:
- 微注射各种蛋白质到细胞细胞质中.
- 细胞冷却和能量耗尽会破坏运输.
- 在现场定位研究以分析受体相互作用.
主要成果:
- 小的非核蛋白质扩散到冷却或能量耗尽的细胞的核中.
- 通过冷却或能量耗尽,大型含有NLS蛋白质的便利运输被阻止.
- 含有NLS的小蛋白质 (海斯H1,NLS-细胞染色体c) 的运输也被阻止,这表明受体中介.
结论:
- 核进口的基因素H1和其他小NLS含有的蛋白质是受体介导的,而不是纯粹的扩散.
- 细胞质受体在调节核进口的组织蛋白中发挥作用.
- 这些发现突出了核定位的规范过程,即使是具有NLS的小分子.
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