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

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.

SUBMITTER: Munteanu A

PROVIDER: S-EPMC4023129 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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

Munteanu Andreea A Cotterell James J Solé Ricard V RV Sharpe James J

Scientific reports 20140516

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 hypot ...[more]

PMID: 24830352

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