Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany.
Department of Chemistry and Bioscience, Aalborg University, Aalborg East, Denmark.
Plant Cell Environ. 2019 Mar;42(3):854-873. doi: 10.1111/pce.13502. Epub 2019 Jan 28.
Alternating temperatures require fast and coordinated adaptation responses of plants. Cold acclimation has been extensively investigated and results in increased freezing tolerance in Arabidopsis thaliana. Here, we show that the two Arabidopsis accessions, Col-0 and N14, which differ in their freezing tolerance, showed memory of cold acclimation, that is, cold priming. Freezing tolerance was higher in plants exposed to cold priming at 4°C, a lag phase at 20°C, and a second triggering cold stress (4°C) than in plants that were only cold primed. To our knowledge, this is the first report on cold memory improving plant freezing tolerance. The triggering response was distinguishable from the priming response at the levels of gene expression (RNA-Seq), lipid (ultraperformance liquid chromatography-mass spectrometry), and metabolite composition (gas chromatography-mass spectrometry). Transcriptomic responses pointed to induced lipid, secondary metabolism, and stress in Col-0 and growth-related functions in N14. Specific accumulation of lipids included arabidopsides with possible functions as signalling molecules or precursors of jasmonic acid. Whereas cold-induced metabolites such as raffinose and its precursors were maintained in N14 during the lag phase, they were strongly accumulated in Col-0 after the cold trigger. This indicates genetic differences in the transcriptomic and metabolic patterns during cold memory.
交替温度要求植物快速协调地适应反应。低温驯化已被广泛研究，导致拟南芥的抗冻能力增强。在这里，我们表明，在其抗冻能力上存在差异的两个拟南芥品系 Col-0 和 N14 表现出低温驯化的记忆，即低温引发。在 4°C 下接受低温引发处理、在 20°C 下出现滞后期、以及第二次触发冷胁迫（4°C）的植物的抗冻能力高于仅接受低温引发处理的植物。据我们所知，这是关于低温记忆提高植物抗冻能力的首次报道。触发反应在基因表达（RNA-Seq）、脂质（超高效液相色谱-质谱法）和代谢物组成（气相色谱-质谱法）水平上与引发反应不同。转录组反应表明 Col-0 中诱导了脂质、次生代谢和应激，而 N14 中则与生长相关的功能有关。可能具有信号分子或茉莉酸前体功能的特定阿拉伯糖的积累。而在滞后期，低温诱导的代谢物如棉子糖及其前体在 N14 中得以维持，而在冷触发后，它们在 Col-0 中大量积累。这表明在低温记忆过程中，基因在转录组和代谢模式上存在差异。
