Temperature compensation in circadian clock models
Temperature compensation in circadian clock models
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DOI：
10.1016/j.jtbi.2004.10.012
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发表时间：
2005-04-21
影响因子：
2
通讯作者：
Iwasa, Y
中科院分区：
文献类型：
--
作者：
Kurosawa, G;Iwasa, Y
生物体的昼夜节律钟有一个不随环境温度变化的自由运行周期。当所有反应步骤的速率随温度增加时，在产生节奏的生化网络中研究了这种性质“温度补偿”。当所有的速率参数都以相同的因子增强时，周期变得更短。然而，随着蛋白质的降解速率和/或时钟基因的转录速率的增加（它们的弹性为正），该周期变得更长。这适用于包括N-变量模型和PER-TIM双振荡器模型在内的广泛模型，条件是（1）分支反应（例如蛋白质或mRNA的降解）是强饱和的，并且（2）核蛋白的转录抑制的协同性不是很大。果蝇PER蛋白降解的强烈温度敏感性和/或PER基因的温度敏感性选择性剪接可能是昼夜节律钟的温度补偿机制。(c)2004 Elsevier Ltd.保留所有权利。
Circadian clock of organisms has a free-running period that does not change much with ambient temperature. This property "temperature compensation" is studied when the rate of all reaction steps increase with temperature in the biochemical network generating the rhythm. The period becomes shorter when all the rate parameters are enhanced by the same factor. However, the period becomes longer as degradation rate of proteins and/or transcription rate of the clock gene increase (their elasticity is positive). This holds for a wide range of models, including N-variable model, and PER-TIM double oscillator model, provided that (1) branch reactions (e.g. degradation of proteins or mRNAs) are strongly saturated, and that (2) the cooperativity of transcription inhibition by nuclear proteins is not very large. A strong temperature sensitivity of degradation of PER proteins and/or temperature- sensitive alternative splicing of per gene, known for Drosophila, can be mechanisms for the temperature compensation of circadian clock. (c) 2004 Elsevier Ltd. All rights reserved.