Key Laboratory of Black Soil Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China.
College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
Int J Mol Sci. 2023 Jul 12;24(14):11348. doi: 10.3390/ijms241411348.
Abscisic acid (ABA) plays a vital role in the induction of low temperature tolerance in plants. To understand the molecular basis of this phenomenon, we performed a proteomic analysis on an ABA-deficit mutant barley () and its wild type (cv Steptoe) under control conditions (25/18 °C) and after exposure to 0 °C for 24 h. Most of the differentially abundant proteins were involved in the processes of photosynthesis and metabolisms of starch, sucrose, carbon, and glutathione. The chloroplasts in leaves were more severely damaged, and the decrease in Fv/Fm was larger in plants compared with WT under low temperature. Under low temperature, plants possessed significantly higher activities of ADP-glucose pyrophosphorylase, fructokinase, monodehydroascorbate reductase, and three invertases, but lower UDP-glucose pyrophosphorylase activity than WT. In addition, concentrations of proline and soluble protein were lower, while concentration of HO was higher in plants compared to WT under low temperature. Collectively, the results indicated that ABA deficiency induced modifications in starch and sucrose biosynthesis and sucrolytic pathway and overaccumulation of reactive oxygen species were the main reason for depressed low temperature tolerance in barley, which provide novel insights to the response of barley to low temperature under future climate change.
脱落酸（ABA）在植物低温诱导耐性中起着至关重要的作用。为了理解这一现象的分子基础，我们对 ABA 缺陷突变体大麦（）及其野生型（cv Steptoe）在对照条件（25/18°C）和暴露于 0°C 24 小时后进行了蛋白质组分析。大多数差异丰度蛋白参与光合作用和淀粉、蔗糖、碳和谷胱甘肽的代谢过程。与 WT 相比，在低温下突变体叶片中的叶绿体受到更严重的损伤，并且 Fv/Fm 的下降幅度更大。在低温下，突变体具有更高的 ADP-葡萄糖焦磷酸化酶、果糖激酶、单脱氢抗坏血酸还原酶和三种转化酶的活性，但 UDP-葡萄糖焦磷酸化酶的活性低于 WT。此外，与 WT 相比，突变体在低温下脯氨酸和可溶性蛋白的浓度较低，而 HO 的浓度较高。总的来说，这些结果表明 ABA 缺乏诱导了淀粉和蔗糖生物合成以及蔗糖分解途径的改变，以及活性氧的过度积累是大麦低温耐性下降的主要原因，这为大麦在未来气候变化下对低温的响应提供了新的见解。
