Department of Biology, Genetics Institute, and Plant Molecular & Cellular Biology Program, University of Florida, Gainesville, Florida, United States of America.
PLoS One. 2013;8(3):e57118. doi: 10.1371/journal.pone.0057118. Epub 2013 Mar 22.
Maintaining metabolic homeostasis is critical for plant growth and development. Here we report proteome and metabolome changes when the metabolic homeostasis is perturbed due to gene-dosage dependent mutation of Arabidopsis isopropylmalate dehydrogenases (IPMDHs). By integrating complementary quantitative proteomics and metabolomics approaches, we discovered that gradual ablation of the oxidative decarboxylation step in leucine biosynthesis caused imbalance of amino acid homeostasis, redox changes and oxidative stress, increased protein synthesis, as well as a decline in photosynthesis, which led to rearrangement of central metabolism and growth retardation. Disruption of IPMDHs involved in aliphatic glucosinolate biosynthesis led to synchronized increase of both upstream and downstream biosynthetic enzymes, and concomitant repression of the degradation pathway, indicating metabolic regulatory mechanisms in controlling glucosinolate biosynthesis.
维持代谢平衡对于植物的生长和发育至关重要。在这里，我们报告了当由于拟南芥异丙基苹果酸脱氢酶（IPMDHs）的基因剂量依赖性突变导致代谢平衡受到干扰时，蛋白质组和代谢组的变化。通过整合互补的定量蛋白质组学和代谢组学方法，我们发现，在亮氨酸生物合成中逐步消除氧化脱羧步骤会导致氨基酸平衡失衡、氧化还原变化和氧化应激，增加蛋白质合成，以及光合作用下降，从而导致中心代谢物的重新排列和生长迟缓。参与脂肪族硫代葡萄糖苷生物合成的 IPMDHs 的破坏导致上游和下游合成酶的同步增加，同时降解途径受到抑制，表明代谢调控机制在控制硫代葡萄糖苷生物合成中发挥作用。
