来自相互关联的正负反循环的强大,可调节的生物振荡.
Tony Yu-Chen Tsai1, Yoon Sup Choi, Wenzhe Ma
1Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305-5174, USA.
Science (New York, N.Y.)
|July 5, 2008
概括
具有正反环和负反环的生物振荡器提供可调频率和稳定的振幅. 这种设计比简单的负反系统更强大,更容易发展.
科学领域:
- 系统生物学 系统生物学
- 分子生物学分子生物学
- 计算生物学 计算生物学
背景情况:
- 基因和蛋白质的相互作用可以产生持续的生物振荡.
- 许多生物振荡器包括负和正反循环,但优势尚不清楚.
研究的目的:
- 研究生物振荡器中正加负反循环的功能优势,与单独的负反相比.
- 了解这些反结构如何影响振荡频率和振幅.
- 探索不同振荡器设计的强度和进化方面.
主要方法:
- 基因或蛋白质相互作用网络的计算建模和模拟.
- 在不同的参数条件下分析振荡频率和振幅.
- 负反的可调性,稳定性和进化潜力的比较与正加负反振荡器模型.
主要成果:
- 负反振荡器显示,在不影响振幅的情况下调整频率的能力有限.
- 积极加负反振荡器允许频率的广泛调整,几乎具有恒定的振幅.
- 这些双反系统表现出增强的稳定性和易于进化的能力.
结论:
- 积极加负反循环为需要调节频率的生物节奏提供了显著的优势,例如细胞周期和心跳.
- 这些系统的增强的捕捞能力和稳定性解释了它们在生物系统中的普遍性.
- 这种设计为产生生物振荡提供了更具适应性和可进化的机制.
相关概念视频
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Negative feedback loops
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Upon receiving an input signal, the cellular response rapidly increases until a threshold is reached. Beyond this threshold, a negative feedback loop...
01:18Positive and Negative Feedback Loops
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01:23Root Loci for Positive-Feedback Systems
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02:19Circadian Rhythms and Gene Regulation
The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent years,...
01:18Negative and Positive Feedback
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