He Caiyun, Gao Guori, Zhang Jianguo, Duan Aiguo, Luo Hongmei
State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of the State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, People's Republic of China.
State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of the State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, People's Republic of China ; Collaborative Innovation Center of Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, People's Republic of China.
Proteome Sci. 2016 Oct 7;14:14. doi: 10.1186/s12953-016-0103-z. eCollection 2016.
Low temperature is one of the crucial environmental factors limiting the productivity and distribution of plants. Sea buckthorn ( L.), a well recognized multipurpose plant species, live successfully in in cold desert regions. But their molecular mechanisms underlying cold tolerance are not well understood.
Physiological and biochemical responses to low-temperature stress were studied in seedlings of sea buckthorn. Differentially expressed protein spots were analyzed using multiplexing fluorescent two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) coupled with matrix-assisted laser desorption/ionization (MALDI) time-of-flight/time-of-flight (TOF/TOF) mass spectrometry (MS), the concentration of phytohormone was measured using enzyme-linked immunosorbent assay, and a spectrophotometric assay was used to measure enzymatic reactions.
With the increase of cold stress intensity, the photosynthesis rate, transpiration rate, stomatal conductance in leaves and contents of abscisic acid (ABA) and indole acetic acid (IAA) in roots decreased significantly; however, water-use efficiency, ABA and zeatin riboside in leaves increased significantly, while cell membrane permeability, malondialdehyde and IAA in leaves increased at 7 d and then decreased at 14 d. DIGE and MS/MS analysis identified 32 of 39 differentially expressed protein spots under low-temperature stress, and their functions were mainly involved in metabolism, photosynthesis, signal transduction, antioxidative systems and post-translational modification.
The changed protein abundance and corresponding physiological-biochemical response shed light on the molecular mechanisms related to cold tolerance in cold-tolerant plants and provide key candidate proteins for genetic improvement of plants.
低温是限制植物生产力和分布的关键环境因素之一。沙棘（胡颓子科沙棘属）是一种广为人知的多用途植物物种，能在寒冷沙漠地区成功生长。但其耐寒的分子机制尚不清楚。
研究了沙棘幼苗对低温胁迫的生理生化响应。采用多重荧光二维荧光差异凝胶电泳（2D-DIGE）结合基质辅助激光解吸/电离（MALDI）飞行时间/飞行时间（TOF/TOF）质谱（MS）分析差异表达的蛋白质斑点，采用酶联免疫吸附测定法测定植物激素浓度，并用分光光度法测定酶促反应。
随着冷胁迫强度的增加，叶片的光合速率、蒸腾速率、气孔导度以及根中脱落酸（ABA）和吲哚乙酸（IAA）的含量显著降低；然而，叶片的水分利用效率、ABA和玉米素核苷显著增加，而叶片的细胞膜通透性、丙二醛和IAA在7天时增加，14天时下降。DIGE和MS/MS分析鉴定出低温胁迫下39个差异表达蛋白质斑点中的32个，其功能主要涉及代谢、光合作用、信号转导、抗氧化系统和翻译后修饰。
蛋白质丰度的变化及相应的生理生化反应揭示了耐寒植物耐寒性相关的分子机制，并为植物遗传改良提供了关键候选蛋白。
