Extreme low temperature tolerance in woody plants.
Extreme low temperature tolerance in woody plants.
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DOI：
10.3389/fpls.2015.00884
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发表时间：
2015
影响因子：
5.6
通讯作者：
Kjellsen TD
中科院分区：
文献类型：
--
作者：
Strimbeck GR;Schaberg PG;Fossdal CG;Schröder WP;Kjellsen TD
在北方到北极的环境和高山中的木本植物在长期暴露于-40 ° C以下的温度和-60 ° C以下的最低温度下生存，实验室测试表明，这些物种中的许多也可以在-196 ° C的液氮中存活。驯化过程中发生的生化变化的研究，包括最近的蛋白质组学和代谢组学研究，已经确定了碳水化合物和相容性溶质浓度，膜脂组成和蛋白质，特别是蛋白质，可能有重要作用的生存在极端低温（ELT）的变化。对膜应力和应变的生物物理机制的考虑导致以下关于ELT下存活的细胞和分子机制的假设：（1）脂质组成的变化在高于脂质相变温度（-20至-30 ° C）的温度下稳定膜，防止导致不可逆损伤的相变。(2)高浓度的寡糖促进冷冻脱水细胞中细胞质的玻璃化或高粘度，这将防止膜之间的有害相互作用。(3)脱水蛋白结合膜并进一步促进玻璃化或起硬脂作用以防止膜-膜相互作用。
Woody plants in boreal to arctic environments and high mountains survive prolonged exposure to temperatures below -40°C and minimum temperatures below -60°C, and laboratory tests show that many of these species can also survive immersion in liquid nitrogen at -196°C. Studies of biochemical changes that occur during acclimation, including recent proteomic and metabolomic studies, have identified changes in carbohydrate and compatible solute concentrations, membrane lipid composition, and proteins, notably dehydrins, that may have important roles in survival at extreme low temperature (ELT). Consideration of the biophysical mechanisms of membrane stress and strain lead to the following hypotheses for cellular and molecular mechanisms of survival at ELT: (1) Changes in lipid composition stabilize membranes at temperatures above the lipid phase transition temperature (-20 to -30°C), preventing phase changes that result in irreversible injury. (2) High concentrations of oligosaccharides promote vitrification or high viscosity in the cytoplasm in freeze-dehydrated cells, which would prevent deleterious interactions between membranes. (3) Dehydrins bind membranes and further promote vitrification or act stearically to prevent membrane–membrane interactions.