对于复制检查点的prolyl异构酶Pin1的要求
K E Winkler1, K I Swenson, S Kornbluth
1Department of Pharmacology and Cancer Biology, Duke University Medical Center, Box 3813, Durham, NC 27710, USA.
概括
基基异构酶Pin1对于DNA复制检查点至关重要. 没有Pin1,细胞过早进入线粒分裂,表明其在延迟细胞分裂的作用,直到DNA复制完成.
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:
- 基-基异构酶Pin1在细胞循环调节中起作用.
- 在DNA复制检查点中Pin1的特定功能尚未完全理解.
研究的目的:
- 为了研究Pin1在Xenopus laevis蛋提取物中的DNA复制检查点中的作用.
- 为了确定Pin1是否需要防止在复制压力期间过早的线粒体进入.
主要方法:
- 在Xenopus laevis的蛋提取物中没有Pin1.1.
- 使用阿菲迪科林抑制了DNA复制.
- 再组合野生型Pin1和一个不活跃的突变物被添加,以评估检查点功能的救援.
- 分析了Cdc25酸化,Cdc2/cyclin B活性和MPM-2表位的水平.
主要成果:
- 当DNA复制被抑制时,pin1贫乏的提取物过早进入线粒分裂.
- 添加野生类型的Pin1恢复了复制检查点,防止过早的线粒体进入.
- 一个异构酶不活跃的Pin1突变体未能挽救检查点缺陷.
- 过早的线粒分裂与Cdc25高酸化和Cdc2/cyclin B激活有关.
结论:
- 在Xenopus中,Pin1对于DNA复制检查点至关重要.
- 需要Pin1活动来延迟发生线粒分裂的开始,以应对不完整的DNA复制.
- Pin1很可能通过调节关键细胞循环蛋白,如Cdc25.
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