Key Laboratory of Mass Spectrometry Imaging and Metabolomics, Minzu University of China, National Ethnic Affairs Commission, Beijing 100081, China; Key Laboratory of Ecology and Environment in Minority Areas, Minzu University of China, National Ethnic Affairs Commission, Beijing 100081, China; College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.
Key Laboratory of Mass Spectrometry Imaging and Metabolomics, Minzu University of China, National Ethnic Affairs Commission, Beijing 100081, China; Key Laboratory of Ecology and Environment in Minority Areas, Minzu University of China, National Ethnic Affairs Commission, Beijing 100081, China; College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.
Int J Biol Macromol. 2023 Jun 15;240:124479. doi: 10.1016/j.ijbiomac.2023.124479. Epub 2023 Apr 16.
Ammopiptanthus mongolicus, an evergreen broad-leaved plant, can tolerate severe freezing stress (temperatures as low as -20 °C in winter). The apoplast is the space outside the plasma membrane that plays an important role in plant responses to environmental stress. Here, we investigated, using a multi-omics approach, the dynamic alterations in the levels of proteins and metabolites in the apoplast and related gene expression changes involved in the adaptation of A. mongolicus to winter freezing stress. Of the 962 proteins identified in the apoplast, the abundance of several PR proteins, including PR3 and PR5, increased significantly in winter, which may contribute to winter freezing-stress tolerance by functioning as antifreeze proteins. The increased abundance of the cell-wall polysaccharides and cell wall-modifying proteins, including PMEI, XTH32, and EXLA1, may enhance the mechanical properties of the cell wall in A. mongolicus. Accumulation of flavonoids and free amino acids in the apoplast may be beneficial for ROS scavenging and the maintenance of osmotic homeostasis. Integrated analyses revealed gene expression changes associated with alterations in the levels of apoplast proteins and metabolites. Our study improved the current understanding of the roles of apoplast proteins and metabolites in plant adaptation to winter freezing stress.
沙冬青是一种常绿阔叶植物，能够耐受严寒的冬季冻害（冬季温度可低至-20°C）。质外体是细胞膜以外的空间，在植物应对环境胁迫中起着重要作用。在这里，我们采用多组学方法研究了沙冬青适应冬季冻害的过程中质外体蛋白和代谢物水平的动态变化以及相关基因表达的变化。在鉴定出的 962 种质外体蛋白中，PR 蛋白（如 PR3 和 PR5）的丰度在冬季显著增加，它们可能通过作为抗冻蛋白来提高植物的抗冻能力。细胞壁多糖和细胞壁修饰蛋白（如 PMEI、XTH32 和 EXLA1）的丰度增加，可能增强了沙冬青细胞壁的机械性能。质外体中类黄酮和游离氨基酸的积累可能有利于清除 ROS 和维持渗透平衡。综合分析揭示了与质外体蛋白和代谢物水平变化相关的基因表达变化。本研究提高了我们对质外体蛋白和代谢物在植物适应冬季冻害过程中作用的认识。
