Photorespiratory Bypasses Lead to Increased Growth in Arabidopsis thaliana: Are Predictions Consistent with Experimental Evidence?
Photorespiratory Bypasses Lead to Increased Growth in Arabidopsis thaliana: Are Predictions Consistent with Experimental Evidence?
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DOI：
10.3389/fbioe.2016.00031
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发表时间：
2016
影响因子：
5.7
通讯作者：
Nikoloski Z
中科院分区：
文献类型：
--
作者：
Basler G;Küken A;Fernie AR;Nikoloski Z
可以说，现代植物系统生物学的最大挑战在于预测植物物种，特别是作物在不同的细胞内和外部扰动下的表现。最近，通过代谢工程引入两种不同的光呼吸旁路来提高拟南芥植物的生长。在这里，我们调查这些发现在多大程度上符合基于约束的建模的预测。为了确定所采用的代谢网络模型对预测的影响，我们进行了比较分析，涉及三个国家的最先进的代谢重建的A。thaliana.此外，我们调查了三个方案相对于核酮糖-1，5-二磷酸羧化酶/加氧酶（RuBisCO）的羧化和氧化反应的比率的实验结果。我们证明，条件依赖的生长表型的工程旁路之一，可以通过每个重建，特别是在考虑额外的限制，相对于RuBisCO反应的通量的比率，定性再现。此外，我们的研究结果提供支持的假设，减少光呼吸的工程植物，并表明，具体的变化，在CO2交换以及在代理辅因子营业额与预测的增长在工程植物。我们讨论了我们的研究结果与所使用的模型的结构，所采取的建模方法，和现有的实验证据。我们的研究为研究通过插入合成反应增加植物生物量的其他策略奠定了基础。
Arguably, the biggest challenge of modern plant systems biology lies in predicting the performance of plant species, and crops in particular, upon different intracellular and external perturbations. Recently, an increased growth of Arabidopsis thaliana plants was achieved by introducing two different photorespiratory bypasses via metabolic engineering. Here, we investigate the extent to which these findings match the predictions from constraint-based modeling. To determine the effect of the employed metabolic network model on the predictions, we perform a comparative analysis involving three state-of-the-art metabolic reconstructions of A. thaliana. In addition, we investigate three scenarios with respect to experimental findings on the ratios of the carboxylation and oxygenation reactions of Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO). We demonstrate that the condition-dependent growth phenotypes of one of the engineered bypasses can be qualitatively reproduced by each reconstruction, particularly upon considering the additional constraints with respect to the ratio of fluxes for the RuBisCO reactions. Moreover, our results lend support for the hypothesis of a reduced photorespiration in the engineered plants, and indicate that specific changes in CO2 exchange as well as in the proxies for co-factor turnover are associated with the predicted growth increase in the engineered plants. We discuss our findings with respect to the structure of the used models, the modeling approaches taken, and the available experimental evidence. Our study sets the ground for investigating other strategies for increase of plant biomass by insertion of synthetic reactions.