Quasi-stable gradients of signaling protein molecules (known as morphogens or ligands) bound to cell receptors are known to be responsible for differential cell signaling and gene expressions. From these follow different stable cell fates and visually patterned tissues in biological development. Recent studies have shown that the relevant basic biological processes yield gradients that are sensitive to small changes in system characteristics (such as expression level of morphogens or receptors) or environmental conditions (such as temperature changes). Additional biological activities must play an important role in the high level of robustness observed in embryonic patterning for example. It is natural to attribute observed robustness to various type of feedback control mechanisms. However, our own simulation studies have shown that feedback control is neither necessary nor sufficient for robustness of the morphogen decapentaplegic (Dpp) gradient in wing imaginal disc of Drosophilas. Furthermore, robustness can be achieved by substantial binding of the signaling morphogen Dpp with nonsignaling cell surface bound molecules (such as heparan sulfate proteoglygans) and degrading the resulting complexes at a sufficiently rapid rate. The present work provides a theoretical basis for the results of our numerical simulation studies.

中文翻译：

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果蝇翼成膜盘信号梯度的稳健性。


已知与细胞受体结合的信号蛋白分子（称为形态发生素或配体）的准稳定梯度负责差异细胞信号传导和基因表达。由此得出生物发育中不同的稳定细胞命运和视觉图案组织。最近的研究表明，相关的基本生物过程产生的梯度对系统特征（例如形态发生素或受体的表达水平）或环境条件（例如温度变化）的微小变化敏感。例如，额外的生物活性必须在胚胎模式中观察到的高水平稳健性中发挥重要作用。将观察到的鲁棒性归因于各种类型的反馈控制机制是很自然的。然而，我们自己的模拟研究表明，反馈控制对于果蝇翅膀成虫盘中形态发生素十肢麻痹（Dpp）梯度的鲁棒性既不是必要的，也不是充分的。此外，通过信号形态发生素 Dpp 与非信号细胞表面结合分子（例如硫酸乙酰肝素蛋白多糖）的大量结合并以足够快的速度降解所得复合物，可以实现稳健性。目前的工作为我们的数值模拟研究结果提供了理论基础。