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Stabilizing and Destabilizing Effects of Embedding 3-node Subgraphs on State Space of Boolean Networks

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 Added by Chikoo Oosawa
 Publication date 2008
  fields Physics
and research's language is English




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We demonstrate the effects of embedding subgraphs using a Boolean network, which is one of the discrete dynamical models for transcriptional regulatory networks. After comparing the dynamical properties of network embedded seven different subgraphs including feedback and feedforward subgraphs, we found that complexity of the state space that increases with longer length of attractors and greater number of attractors is reduced for networks with more feedforward subgraphs. In addition, feedforward subgraphs can also provide higher mutual information with lower entropy in a temporal program of gene expression. Networks with other six subgraphs show opposite effects on dynamics of the networks, is roughly consistent with Thomass conjecture. These results suggest that feedforward subgraphs are one of the favorable local structures in biological complex networks.



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