School of Mathematics and Computational Science and Guangdong Province Key Laboratory of Computational Science, Sun Yat-Sen University, Guangzhou 510275, People's Republic China.
IET Syst Biol. 2013 Feb;7(1):1-10. doi: 10.1049/iet-syb.2011.0090.
Many types of multiple positive feedbacks with each having potentials to generate bistability exist extensively in natural, raising the question of why a particular architecture is present in a cell. In this study, the authors investigate multiple positive feedback loops across three classes: one-loop class, two-loop class and three-loop class, where each class is composed of double positive feedback loop (DPFL) or double negative feedback loop (DNFL) or both. Through large-scale sampling and robustness analysis, the authors find that for a given class, the homogeneous DPFL circuit (i.e. the coupled circuit that is composed of only DPFLs) is more robust than all the other circuits in generating bistable behaviour. In addition, stochastic simulation shows that the low stable state is more robust than the high stable state in homogeneous DPFL whereas the high-stable state is more robust than the low-stable state in homogeneous DNFL circuits. It was argued that this investigation provides insight into the relationship between robustness and network architecture.
在自然界中，存在着许多种具有产生双稳性潜力的多重正反馈，这引发了一个问题，即为什么特定的结构会存在于一个细胞中。在这项研究中，作者研究了跨越三个类别的多重正反馈回路：单回路类、双回路类和三回路类，其中每个类由双正反馈回路 (DPFL) 或双负反馈回路 (DNFL) 或两者组成。通过大规模采样和稳健性分析，作者发现，对于给定的类，同质 DPFL 电路（即仅由 DPFL 组成的耦合电路）在产生双稳行为方面比其他所有电路都更稳健。此外，随机模拟表明，在同质 DPFL 中，低稳定状态比高稳定状态更稳健，而在同质 DNFL 电路中，高稳定状态比低稳定状态更稳健。有人认为，这项研究为稳健性和网络结构之间的关系提供了深入的了解。
