Design principles of stripe-forming motifs: the role of positive feedback

Sci Rep. 2014 May 16:4:5003. doi: 10.1038/srep05003.

Abstract

Interpreting a morphogen gradient into a single stripe of gene-expression is a fundamental unit of patterning in early embryogenesis. From both experimental data and computational studies the feed-forward motifs stand out as minimal networks capable of this patterning function. Positive feedback within gene networks has been hypothesised to enhance the sharpness and precision of gene-expression borders, however a systematic analysis has not yet been reported. Here we set out to assess this hypothesis, and find an unexpected result. The addition of positive-feedback can have different effects on two different designs of feed-forward motif- it increases the parametric robustness of one design, while being neutral or detrimental to the other. These results shed light on the abundance of the former motif and especially of mutual-inhibition positive feedback in developmental networks.

MeSH terms

  • Embryonic Development / genetics*
  • Embryonic Development / physiology*
  • Feedback, Physiological / physiology*
  • Gene Expression / genetics
  • Gene Expression / radiation effects
  • Gene Expression Regulation, Developmental / genetics*
  • Gene Expression Regulation, Developmental / physiology
  • Gene Regulatory Networks / genetics
  • Gene Regulatory Networks / physiology