Arabidobsis Super50 2020 RNAseq

Abiotic stresses cause oxidative damage in plants. Here, we demonstrate that foliar application of an extract from the seaweed Ascophyllum nodosum, SuperFifty (SF), largely prevents paraquat (PQ)-induced oxidative stress in Arabidopsis thaliana. While PQ-stressed plants develop necrotic lesions, plants pre-treated with SF (i.e., primed plants) were unaffected by PQ. Transcriptome analysis revealed induction of reactive oxygen species (ROS) marker genes, genes involved in ROS-induced programmed cell death, and autophagy-related genes after PQ treatment. These changes did not occur in PQ-stressed plants primed with SF. In contrast, upregulation of several carbohydrate metabolism genes, growth, and hormone signaling as well as antioxidant-related genes were specific to SF-primed plants. Metabolomic analyses revealed accumulation of the stress-protective metabolite maltose and the tricarboxylic acid cycle intermediates fumarate and malate in SF-primed plants. Lipidome analysis indicated that those lipids associated with oxidative stress-induced cell death and chloroplast degradation, such as triacylglycerols (TAGs), declined upon SF priming. Our study demonstrated that SF confers tolerance to PQ-induced oxidative stress in A. thaliana, an effect achieved by modulating a range of processes at the transcriptomic, metabolic, and lipid levels.非生物胁迫可对植物造成氧化损伤。本研究证实，叶面喷施泡叶藻（Ascophyllum nodosum）提取物SuperFifty（SF），可显著缓解拟南芥（Arabidopsis thaliana）中百草枯（PQ）诱导的氧化应激。经百草枯胁迫的植株会产生坏死病斑，而经SF预处理（即引发处理植株）的植株则未受百草枯的影响。转录组分析结果显示，百草枯处理后，活性氧（reactive oxygen species, ROS）标记基因、参与ROS诱导的程序性细胞死亡的基因以及自噬相关基因均被诱导上调；但在经SF引发处理的百草枯胁迫植株中，上述基因表达变化并未出现。与之相反，多种碳水化合物代谢基因、生长及激素信号通路相关基因，以及抗氧化相关基因的上调表达，仅在SF引发处理的植株中特异性存在。代谢组分析表明，SF引发处理的植株中，抗胁迫代谢物麦芽糖以及三羧酸循环中间产物延胡索酸和苹果酸发生积累。脂质组分析显示，与氧化应激诱导的细胞死亡及叶绿体降解相关的脂质（如三酰甘油（triacylglycerols, TAGs））的含量在SF引发处理后显著下降。本研究证实，SF可赋予拟南芥抵御百草枯诱导的氧化应激的能力，该效应通过在转录组、代谢组和脂质组层面调控一系列生物学过程得以实现。