1] EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain [2] Universitat Pompeu Fabra (UPF), Dr. Aiguader 88, 08003 Barcelona, Spain.
1] Universitat Pompeu Fabra (UPF), Dr. Aiguader 88, 08003 Barcelona, Spain [2] Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA [3] Institució Catalana de Recerca i Estudis Avancats (ICREA), Pg. Lluís Companys 23, 08010 Barcelona, Spain.
Sci Rep. 2014 May 16;4:5003. doi: 10.1038/srep05003.
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.
将形态发生梯度解释为单一的基因表达条纹是早期胚胎发生中模式形成的基本单位。无论是实验数据还是计算研究，前馈模式都凸显为能够实现这种模式形成功能的最小网络。基因网络内的正反馈被假设为增强基因表达边界的清晰度和精度，但尚未有系统的分析报告。在这里，我们着手评估这一假设，并得到了一个意外的结果。正反馈的添加对两种不同的前馈模式设计会产生不同的影响——它增加了一种设计的参数鲁棒性，而对另一种设计则是中性的或有害的。这些结果揭示了前馈模式的丰富性，特别是在发育网络中相互抑制的正反馈。
