Ran-GTP和Crm1在阻止重复复制中的作用
Ryuji Yamaguchi1, John Newport
1Department of Biology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.
Cell
|April 8, 2003
概括
一个新发现的甲状动物特异性系统通过在S阶段通过与出口因-1/Crm1的结合来禁用MCM螺旋酶来防止DNA重复复制.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 细胞具有调节机制,以确保每个细胞周期的单基因组复制.
- 这些机制阻断了复制前复合体的形成.
- 酵母中已知的调节机制在甲基动物中没有得到保护.
研究的目的:
- 确定控制DNA复制的甲状动物特异性监管系统.
- 研究MCM酶和出口因-1/Crm1在防止重复复制中的作用.
主要方法:
- 使用了Xenopus蛋提取物进行实验分析.
- 通过与出口in-1/Crm1.1的关联评估了MCM酶失活.
- 在核提取物中操纵了Ran-GTP水平,以观察对MCM-染色体协会和重复复制的影响.
主要成果:
- 在S阶段通过与exportin-1/Crm1的结合,可溶性MCM基酶以Ran-GTP和cdk2激酶依赖的方式被非活性化.
- 降低的Ran-GTP水平允许MCM与染色质重新关联,从而诱导重复复制.
- 为了防止重复复制,需要独立于MCM核出口的MCM-Crm1复合体形成.
结论:
- 一个涉及MCM酶和exportin-1/Crm1的甲状动物特异性调控系统控制着DNA复制.
- 导出蛋白-1/Crm1在甲基动物中扮演着双重的角色,它既调解核导出,又阻断DNA复制.
相关概念视频
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01:42Directionality of Nuclear Transport
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