Evolutionary models for formation of network motifs and modularity in the Saccharomyces transcription factor network.

ABSTRACT: Many natural and artificial networks contain overrepresented subgraphs, which have been termed network motifs. In this article, we investigate the processes that led to the formation of the two most common network motifs in eukaryote transcription factor networks: the bi-fan motif and the feed-forward loop. Around 100 million y ago, the common ancestor of the Saccharomyces clade underwent a whole-genome duplication event. The simultaneous duplication of the genes created by this event enabled the origin of many network motifs to be established. The data suggest that there are two primary mechanisms that are involved in motif formation. The first mechanism, enabled by the substantial plasticity in promoter regions, is rewiring of connections as a result of positive environmental selection.

SUBMITTER: Ward JJ 

PROVIDER: S-EPMC2041975 | biostudies-literature | 2007 Oct

REPOSITORIES: biostudies-literature