细胞周期振荡器的系统层次剖析:绕过正反会产生抑制振荡
Joseph R Pomerening1, Sun Young Kim, James E Ferrell
1Department of Molecular Pharmacology, Stanford University School of Medicine, Stanford, California 94305, USA. pomereni@stanford.edu
Cell
|August 27, 2005
概括
积极的反循环对于胚胎细胞周期振荡至关重要,确保周期破坏和细胞周期进展的适当时间. 破坏这些循环会导致更快,减弱的振荡,影响细胞分裂和DNA复制.
科学领域:
- 细胞生物学 细胞生物学
- 系统生物学 系统生物学
- 发展生物学 发展生物学
背景情况:
- 细胞循环的进展依赖于反循环,包括一个涉及Cdc2和亚纳酶促进复合体 (APC) 的负反循环.
- 虽然负反可以产生振荡,但正反在Cdc2/APC系统中的作用尚不清楚.
研究的目的:
- 评估胚胎细胞周期振荡器中正反回路的功能重要性.
- 了解反子电路的组合如何产生振荡行为.
主要方法:
- 在Cdc2/APC系统中进行实验操纵以"短路"正反.
- 分析Cdc2活动振荡所产生的变化及其下游影响.
主要成果:
- 短路的积极反导致了Cdc2活动的更快,更少的突然和减弱的振荡.
- 这种干扰危害了循环破坏,线粒体退出和DNA复制.
结论:
- 积极反循环在胚胎细胞周期中起着关键的系统级作用.
- 振荡来自积极和消极反的相互作用,类似于心脏起器神经元.
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