在Xenopus蛋中由GTP结合的Ran Ran诱导的微管星的自我组织
T Ohba1, M Nakamura, H Nishitani
1Department of Molecular Biology, Graduate School of Medical Science, Kyushu University, Maidashi Higashi-ku, Fukuoka 812-8582, Japan.
Science (New York, N.Y.)
|May 21, 1999
概括
关氨酸核酸交换因子RCC1对于微管星的形成至关重要. 通过RCC1调节的Ran GTP驱动微管体的自我组织,需要dynein活动.
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:
- RCC1 (染色体凝聚的调节器1) 是唯一的关氨酸核酸交换因子为Ran.
- 兰是一种类似Ras的小GTPase,对各种细胞过程至关重要.
- 微管星的形成对于细胞分裂和细胞内运输至关重要.
研究的目的:
- 调查RCC1及其下游效应器Ran在微管星形成中的作用.
- 为了确定Ran (GTP或GDP) 促进微管组织的特定核酸结合状态.
- 为了阐明dynein在Ran介导的微管自身组织中的参与.
主要方法:
- 使用过的Xenopus蛋提取物在二次变异 II中被捕.
- 从蛋提取物中减少RCC1,以评估其必要性.
- 使用Ran GTP或Ran GDP在RCC1-贫化的提取物中诱导微管星形成.
- 评估了观察到的微管组织中对dynein活性的要求.
主要成果:
- RCC1核酸交换活动对于微管星的形成是不可或缺的.
- 兰GTP,但不是RanGDP,诱导了RCC1-贫乏的提取物中自发的微管星自我组织.
- 由Ran-GTP诱导的微管自身组织过程需要dynein活动.
结论:
- 兰GTP是微管网形成的关键调节者.
- 在Ran核酸交换中的RCC1的功能对于启动微管组织至关重要.
- 丁氨酸在微管星的Ran介导组合中起着至关重要的作用.
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