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Finding the center reliably: robust patterns of developmental gene expression

Martin Howard·Pieter Rein ten Wolde
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Abstract

We investigate a mechanism for the robust identification of the center of a developing biological system. We assume the existence of two morphogen gradients, an activator emanating from the anterior, and a co-repressor from the posterior. The co-repressor inhibits the action of the activator in switching on target genes. We apply this system to Drosophila embryos, where we predict the existence of a hitherto undetected posterior co-repressor. Using mathematical modelling, we show that a symmetric activator-co-repressor model can quantitatively explain the precise mid-embryo expression boundary of the hunchback gene, and the scaling of this pattern with embryo size.

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Martin Howard, Pieter Rein ten Wolde. 2005-11-10. Finding the center reliably: robust patterns of developmental gene expression. https://doi.org/10.1103/physrevlett.95.208103

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