Regulatory networks and connected components of the neutral space
Regulatory networks and connected components of the neutral space
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DOI：
10.1140/epjb/e2010-00176-4
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发表时间：
2010-09-01
影响因子：
1.6
通讯作者：
Klemm, K.
中科院分区：
文献类型：
--
作者：
Boldhaus, G.;Klemm, K.
活细胞的功能在很大程度上取决于其调控网络的结构，包括调控基因之间的非线性相互作用。这种监管系统的稳定性和可演化性的一个重要因素是中立性——通常，大量的替代网络结构会产生必要的动态。在这里，我们研究了酵母细胞周期的离散化调控动力学[Li et al.， PNAS， 2004]以及能够复制它的一组网络，我们称之为功能性的。其中，经验酵母野生型网络在稀疏布线方面接近最优。在建立或删除单一相互作用的点突变下，功能网络的中性空间被分割成千分之一的4.7 x 10(8)个组件。其中一个较小的包含wildtype网络。平均而言，与该野生型成分之外的网络相比，突变可从野生型到达的功能网络更稀疏，具有更高的噪声弹性和更少的不动点吸引子。
The functioning of a living cell is largely determined by the structure of its regulatory network, comprising non-linear interactions between regulatory genes. An important factor for the stability and evolvability of such regulatory systems is neutrality - typically a large number of alternative network structures give rise to the necessary dynamics. Here we study the discretized regulatory dynamics of the yeast cell cycle [Li et al., PNAS, 2004] and the set of networks capable of reproducing it, which we call functional. Among these, the empirical yeast wildtype network is close to optimal with respect to sparse wiring. Under point mutations, which establish or delete single interactions, the neutral space of functional networks is fragmented into a parts per thousand 4.7 x 10(8) components. One of the smaller ones contains the wildtype network. On average, functional networks reachable from the wildtype by mutations are sparser, have higher noise resilience and fewer fixed point attractors as compared with networks outside of this wildtype component.