Systems Biology and Mathematical Modeling; Max Planck Institute of Molecular Plant Physiology; Potsdam-Golm, Germany.
Plant Signal Behav. 2013 Sep;8(9). doi: 10.4161/psb.25480. Epub 2013 Jun 24.
Classical flux balance analysis predicts steady-state flux distributions that maximize a given objective function. A recent study, Schuetz et al., (1) demonstrated that competing objectives constrain the metabolic fluxes in E. coli. For plants, with multiple cell types, fulfilling different functions, the objectives remain elusive and, therefore, hinder the prediction of actual fluxes, particularly for changing environments. In our study, we presented a novel approach to predict flux capacities for a large collection of metabolic pathways under eight different temperature and light conditions. (2) By integrating time-series transcriptomics data to constrain the flux boundaries of the metabolic model, we captured the time- and condition-specific state of the network. Although based on a single time-series experiment, the comparison of these capacities to a novel null model for transcript distribution allowed us to define a measure for differential behavior that accounts for the underlying network structure and the complex interplay of metabolic pathways.
经典通量平衡分析预测了在给定目标函数下的稳态通量分布。最近的一项研究表明,Schuetz 等人(1)竞争目标限制了大肠杆菌中的代谢通量。对于具有多种细胞类型、履行不同功能的植物来说,目标仍然难以捉摸,因此阻碍了实际通量的预测,特别是对于不断变化的环境。在我们的研究中,我们提出了一种新的方法来预测在八种不同温度和光照条件下大量代谢途径的通量能力。(2)通过整合时间序列转录组学数据来限制代谢模型的通量边界,我们捕捉到了网络的时间和条件特异性状态。尽管基于单个时间序列实验,但将这些能力与转录本分布的新空模型进行比较,使我们能够定义一种用于差异行为的度量方法,该方法考虑了基础网络结构和代谢途径的复杂相互作用。