生物谷报道：细胞内信号以往认为是单一行为，其实从数学模型来看，单一，线性的信号模式，是极其脆弱的，因为只要其中某一个因子（物质）出现问题，表达多或少了，都会导致信号的失真。实际上在细胞内的信号传递是高度精密的，不仅能将不同的信号传递进细胞内，而且能精确地传递定位和定量信息，从而使细胞能精确地外界刺激作出特定的反应。因此信号网络模型被认为是解释信号传递的可能方式。但是细胞信号间crosstalk可以通过反馈和负反馈保证信号的精确性，那么如何保证信号的稳定性？北大Chao Tang最新在酵母中研究酵母的细胞周期信号中惊奇地发现，细胞周期信号具有超强的稳定性，保证酵母能不断地增殖，并提出了数学模型, 这篇文章发表在最近的PNAS上。
The interactions between proteins, DNA, and RNA in living cells constitute molecular networks that govern various cellular functions. To investigate the global dynamical properties and stabilities of such networks, we studied the cell-cycle regulatory network of the budding yeast. With the use of a simple dynamical model, it was demonstrated that the cell-cycle network is extremely stable and robust for its function. The biological stationary state, the G1 state, is a global attractor of the dynamics. The biological pathway, the cell-cycle sequence of protein states, is a globally attracting trajectory of the dynamics. These properties are largely preserved with respect to small perturbations to the network. These results suggest that cellular regulatory networks are robustly designed for their functions.
原文阅读和下载
Fangting Li, Tao Long, Ying Lu, Qi Ouyang, and Chao Tang The yeast cell-cycle network is robustly designed
PNAS 2004 101: 4781-4786; published online before print March 22 2004, 10.1073/pnas.0305937101 [Full Text] [PDF] [Supporting Information]
