一个RNA-出口中介与一个重要的核出口信号
1Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
Nature
|September 26, 1996
概括
一种新发现的酵母蛋白,Gle1,作为一种必不可少的RNA出口因子. Gle1与细胞共因子和核孔蛋白相互作用,这表明HIV-1 Rev蛋白可能模仿其用于病毒RNA输出的功能.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 病毒学 病毒学
背景情况:
- 人类免疫缺陷病毒1型 (HIV-1) 的Rev蛋白对于将病毒信使RNA从核转移到细胞质至关重要.
- 在酵母中,Rev促进了特定RNA的核出口,依赖于核出口信号 (NES) 和与细胞辅因子Rip1.1的相互作用.
- 存在与Rip1相互作用并拥有NES的内源性RNA输出介质是假设的,但尚未证实.
研究的目的:
- 为了识别和描述参与酵母核RNA出口的新型细胞因素.
- 为了研究一种新发现的酵母蛋白,Gle1,在RNA出口途径的背景下所起的作用.
- 探索Gle1和HIV-1 Rev蛋白之间的潜在功能模仿.
主要方法:
- 一种新型酵母蛋白 Gle1 的特性,包括其分子质量和功能域.
- 在Gle1.1内确定核出口信号 (NES) 的位点定向突变发生.
- 对酵母菌株具有突变Gle1.1的RNA出口效率的分析.
- 生物化学测试以确定Gle1,Rip1和Nup100之间的相互作用.
- Gle1在酵母细胞中的亚细胞局部化研究.
主要成果:
- 一种新的必不可少的酵母蛋白,Gle1 (62,000分子质量),被确定并发现包含一个功能性的NES.
- Gle1的NES突变取消了从核中出口的多基化RNA.
- 表明Gle1与细胞辅因子Rip1和核蛋白Nup100相互作用.
- Gle1主要局限于核孔综合体.
结论:
- Gle1被确定为酵母中关键的RNA出口因子,对于核-细胞质RNA转位至关重要.
- Gle1的相互作用形状和定位表明它在导航核孔综合体中发挥着直接作用.
- 这些发现表明,HIV-1 Rev蛋白可能通过模仿Gle1.1.的基本细胞功能来实现病毒RNA输出.
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