Redundancy and fragility in a young but essential gene regulatory network

Early in embryogenesis, C. elegans worms use a short network of interacting and related transcription factors to establish gut cell identity. The goal is to activate a downstream master regulator which stays on throughout a worm’s life and directs gut differentiation and maintenance. Although the network is robust to deletions of some of its trans-activators, the cis-regulation of this master regulator seems to be fragile.

Surprisingly, most of the genes that comprise this network do not exist in half of the Caenorhabditis genus, raising the questions of how they establish gut identity and just where the C. elegans network came from. In this talk I will discuss and model the effects of mutations on transcriptional activity in the network, dissect the cis-regulation of the master regulator, and propose a hypothesis for how the network originated.