证据表明,一个自由运行的振荡器驱动了在芽的酵母细胞周期中的G1事件
1Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 94303, USA.
Nature
|October 12, 1999
概括
发芽酵母具有独立于环林依赖激酶的细胞周期振荡器,允许G1事件即使在细胞分裂被阻止时也继续进行. 这种振荡器确保了及时的进展,类似于早期胚胎细胞.
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:
- 体细胞依赖于序列事件的完成来进行细胞循环的进展.
- 早期的胚胎细胞经常表现出独立的细胞周期振荡器,将事件时间与完成脱.
研究的目的:
- 调查Saccharomyces cerevisiae中一个独立的细胞周期振荡器的存在和特征.
- 为了确定这种振荡器是否独立于关键细胞循环调节器 (如循环林依赖性激酶) 的功能.
主要方法:
- 观察到酵母细胞中缺少重要的线性环林依赖激酶活动的G1阶段事件的周期性激活.
- 分析了细胞周期振荡,这些细胞对没有G1或线性环林相关激酶活性的交配费洛蒙做出了反应.
- 评估了Clb相关激酶活性在强制执行细胞循环依赖性方面的作用.
主要成果:
- 周期性G1事件在没有S阶段或线粒分裂的情况下按计划发生,其周期与野生类型细胞相似.
- 独立于G1环林 (Cln) 和线性环林 (Clb) 相关的激酶活性,观察到类似的振荡.
- 发现Clb相关激酶活性对于在延迟细胞周期进展期间预防过早的G1事件至关重要.
结论:
- 发芽的酵母Saccharomyces cerevisiae具有一个独立的细胞循环振荡器.
- 这种振荡器可以独立于循环素依赖的激酶动力学运行.
- 循环素依赖性激酶活性对于强制执行细胞循环依赖性和预防过早事件至关重要.
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