Spontaneous Self-Assembly of Transcription Factor Based Gene Regulation Networks

We model the transcription factor based regulation network of yeast using a content-based network model that mimicks the recognition of binding motifs on the regulatory regions of the genes. We are thereby able to faithfully reproduce many of the topological features of the gene regulatory network of yeast once the parameters of the yeast genome, in particular the distribution of information coded by the "binding sequences" within the promoter regions is provided as input. The length distribution for the promoter regions is fixed by comparing the k-core analysis of the model network with that of yeast. Our results strongly point to the possibility that the observed topological features are generic to networks formed via sequence-matching between random strings obeying certain length distributions.