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一种巨大的核孔蛋白质,可以结合Ran/TC4
N Yokoyama1, N Hayashi, T Seki
1Department of Molecular Biology, Graduate School of Medical Science, Kyushu-University, Fukuoka, Japan.
Nature
|July 13, 1995
概括
研究人员确定了RanBP2,一种与Ran/TC4 G蛋白结合的新型巨型蛋白质. RanBP2 是一个参与核蛋白进口的核孔复合元件.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 蛋白相互作用 蛋白相互作用
背景情况:
- 兰/TC4是一种小核G蛋白,对细胞循环进展,RNA输出和核蛋白进口至关重要.
- RCC1是一种关氨酸核酸释放因子,与Ran/TC4.4形成复合体.
- 作为RCC1下游的Ran/TC4功能,它有能力抑制RCC1功能丧失缺陷.
研究的目的:
- 为了识别与Ran/TC4结合的新型蛋白质.
- 描述新发现的Ran/TC4结合蛋白的结构和功能.
主要方法:
- 酵母两杂交选,以识别Ran/TC4相互作用蛋白质.
- 蛋白质域分析和序列同质性搜索.
- 免疫定位研究以确定细胞内的蛋白质定位.
- 使用抗体进行功能性测试,以评估核进口中的作用.
主要成果:
- 确定RanBP2,一个由3224个残留物组成的新型蛋白质,作为Ran/TC4结合伙伴.
- 兰BP2具有独特的域结构,包括含有白的重复,兰BP1同源域,指纹图案和环菲林同源.
- RanBP2 含有核孔综合体 (NPC) 蛋白质的 XFXFG 图案特征,并定位到 NPC.
- 对RanBP2的抗体抑制了NLS介导的核进口,这表明它在这个过程中发挥了作用.
结论:
- RanBP2是一种新型的大型NPC蛋白,与Ran/TC4相互作用.
- RanBP2在通过NPC通过NLS介导的核蛋白进口中发挥着功能性作用.
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