Root Biology Center, State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China.
Genes (Basel). 2019 May 27;10(5):402. doi: 10.3390/genes10050402.
Proton toxicity is one of the major environmental stresses limiting crop production and becomes increasingly serious because of anthropogenic activities. To understand acid tolerance mechanisms, the plant growth, mineral nutrients accumulation, and global transcriptome changes in soybean () in response to long-term acidity stress were investigated. Results showed that acidity stress significantly inhibited soybean root growth but exhibited slight effects on the shoot growth. Moreover, concentrations of essential mineral nutrients were significantly affected by acidity stress, mainly differing among soybean organs and mineral nutrient types. Concentrations of phosphorus (P) and molybdenum (Mo) in both leaves and roots, nitrogen (N), and potassium (K) in roots and magnesium (Mg) in leaves were significantly decreased by acidity stress, respectively. Whereas, concentrations of calcium (Ca), sulfate (S), and iron (Fe) were increased in both leaves and roots. Transcriptome analyses in soybean roots resulted in identification of 419 up-regulated and 555 down-regulated genes under acid conditions. A total of 38 differentially expressed genes (DEGs) were involved in mineral nutrients transportation. Among them, all the detected five GmPTs, four GmZIPs, two GmAMTs, and GmKUPs, together with GmIRT1, GmNramp5, GmVIT2.1, GmSKOR, GmTPK5, and GmHKT1, were significantly down-regulated by acidity stress. Moreover, the transcription of genes encoding transcription factors (e.g., GmSTOP2s) and associated with pH stat metabolic pathways was significantly up-regulated by acidity stress. Taken together, it strongly suggests that maintaining pH stat and mineral nutrient homeostasis are adaptive strategies of soybean responses to acidity stress, which might be regulated by a complex signaling network.
质子毒性是限制作物生产的主要环境胁迫之一，由于人为活动的影响，这种胁迫变得越来越严重。为了了解耐酸机制，研究了长期酸胁迫下大豆（）的生长、矿质养分积累和全转录组变化。结果表明，酸度胁迫显著抑制大豆根的生长，但对地上部生长影响较小。此外，矿质养分浓度受酸度胁迫的显著影响，主要因大豆器官和矿质养分类型而异。酸度胁迫显著降低了叶片和根系中的磷（P）和钼（Mo）、氮（N）和钾（K）以及叶片中的镁（Mg）的浓度，而叶片和根系中的钙（Ca）、硫酸盐（S）和铁（Fe）浓度则增加。在大豆根系的转录组分析中，在酸性条件下鉴定出 419 个上调和 555 个下调基因。共有 38 个差异表达基因（DEGs）参与了矿质养分的运输。其中，所有检测到的五个 GmPTs、四个 GmZIPs、两个 GmAMTs 和 GmKUPs，以及 GmIRT1、GmNramp5、GmVIT2.1、GmSKOR、GmTPK5 和 GmHKT1，均被酸度胁迫显著下调。此外，编码与 pH 稳态代谢途径相关的转录因子（如 GmSTOP2s）的基因的转录也被酸度胁迫显著上调。综上所述，这强烈表明维持 pH 稳态和矿质养分稳态是大豆应对酸度胁迫的适应性策略，可能受复杂的信号网络调控。
