脉胞菌节律调控网络的鲁棒性

耿玮++殷鑫++施萌++王益

摘 要：生物钟是生命活动以24小时左右为周期的波动，但是其一旦遭到扰乱，会导致严重后果。因而，保持其振荡的鲁棒性与周期长度（接近24小时）的鲁棒性是生物钟的核心问题。有研究发现，生物钟网络中除了一个主要的负反馈调节之外，通常都有其他的反馈调控机制，如脉胞菌的主要反馈是转录调控，但有额外的转录后调控。我们猜想：这些额外反馈调控主要用来维持生物钟的鲁棒性。我们在原有三变量脉胞菌模型基础上，增加了额外调控项，运用数值模拟，分别对比是否有额外调控的两种情况对环境的容忍程度，得以验证我们的猜想。进一步我们求出在保持振荡时，脉胞菌所能容忍的环境变化范围的理论值，对比理论值和模拟值，引入分叉定理进行理论分析，为理解生物钟鲁棒性机理和相关疾病原因提供理论基础。

关键词：生物钟 调控通路 数学模型 鲁棒性负反馈回路

中图分类号：TP39 文献标识码：A 文章编号：1674-098X（2015）02（b）-0001-04

Robustness of Rhythm Regulatory Network in Neurospora

Geng Wei Yin Xin Shi Meng Wang Yi

（Soochow University， Suzhou Jiangsu，215000，China）

Abstract：Circadian rhythm is a biological process that displays an endogenous，entrainable oscillation of about 24 hours. Circadian disruption may result in serious consequences.Therefore， maintaining the robustness of the oscillation and period length （which is close to 24 h） is a core task of circadian rhythm.After literature mining，we found that besides the primary negative feedback， there are some other auxiliary feedback loops in circadian systems.For example，there is a primary transcriptional feedback in Neurospora with an extra post-transcriptional regulation. As a result，we hypothesize that these extra feedback loops can contribute to the robustness. We establish two three-dimensional dynamical models and conduct the numerical simulation with MATLB after we add to an extra post-transcription. Through comparison of the circumstance（parameters）tolerance between two models， our assumption is verified. Furthermore， we get the theory values of range，of which Neurosppora can tolerate environmental change. Comparing the difference of theoretical and simulate values， we make some theoretical analysis of them after introducing Hopf bifurcation， which would provides theoretical basis founder standing the mechanism of the robustness of biological clock and related causes of diseases.

Key Words： The Biological Clock；Regulatory Pathway；The Mathematical Model；Robustness；The Negative Feedback Loopendprint