Epigenomics Project, Genopole, Tour Evry 2, 523 Terrasses de l'Agora, Evry cedex, France.
J Theor Biol. 2009 Nov 21;261(2):176-93. doi: 10.1016/j.jtbi.2009.07.023. Epub 2009 Jul 28.
Based on a non-equilibrium mechanism for spatial pattern formation we study how position information can be controlled by locally coupled discrete dynamical networks, similar to gene regulation networks of cells in a developing multicellular organism. As an example we study the developmental problems of domain formation and proportion regulation in the presence of noise, as well as in the presence of cell flow. We find that networks that solve this task exhibit a hierarchical structure of information processing and are of similar complexity as developmental circuits of living cells. Proportion regulation is scalable with system size and leads to sharp, precisely localized boundaries of gene expression domains, even for large numbers of cells. A detailed analysis of noise-induced dynamics, using a mean-field approximation, shows that noise in gene expression states stabilizes (rather than disrupts) the spatial pattern in the presence of cell movements, both for stationary as well as growing systems. Finally, we discuss how this mechanism could be realized in the highly dynamic environment of growing tissues in multicellular organisms.
基于非平衡空间模式形成机制，我们研究了位置信息如何通过局部耦合离散动力网络进行控制，类似于发育多细胞生物中细胞的基因调控网络。作为一个例子，我们研究了存在噪声和细胞流动时的域形成和比例调节的发展问题。我们发现，解决这个任务的网络表现出信息处理的层次结构，并且与活细胞的发育电路具有相似的复杂性。比例调节具有可扩展性，可以在系统尺寸上实现，并且即使对于大量细胞，也可以导致基因表达域的边界精确地本地化。使用平均场近似对噪声诱导动力学的详细分析表明，在细胞运动存在的情况下，噪声会稳定（而不是破坏）基因表达状态的空间模式，无论是对于静止系统还是增长系统都是如此。最后，我们讨论了这种机制如何在多细胞生物中不断增长的组织的高度动态环境中实现。
