Institute of Plant Genetics, Polish Academy of Sciences, Strzeszyńska 34, 60-479 Poznań, Poland.
J Plant Physiol. 2011 Jul 15;168(11):1271-9. doi: 10.1016/j.jplph.2011.01.029. Epub 2011 Apr 12.
Perennial ryegrass (Lolium perenne) is a high quality forage and turf grass mainly due to its excellent nutritive values and rapid establishment rate. However, this species has limited ability to perform in harsh winter climates. Though winter hardiness is a complex trait, it is commonly agreed that frost tolerance (FT) is its main component. Species growing in temperate regions can acquire FT through exposure to low, non-lethal temperatures, a phenomenon known as cold acclimation (CA). The research on molecular basis of FT has been performed on the model plants, but they are not well adapted to extreme winter climates. Thus, the mechanisms of cell response to low temperature in winter crops and agronomically important perennial grasses have yet to be revealed. Here, two L. perenne plants with contrasting levels of FT, high frost tolerant (HFT) and low frost tolerant (LFT) plants, were selected for comparative proteomic research. The work focused on analyses of leaf protein accumulation before and after 2, 8, 26 h, and 3, 5, 7, 14 and 21 days of CA, using a high-throughput two-dimensional electrophoresis, and on the identification of proteins which were accumulated differentially between the selected plants by the application of mass spectrometry (MS). Analyses of 580 protein profiles revealed a total of 42 (7.2%) spots that showed at a minimum of 1.5-fold differences in protein abundance, at a minimum of at one time point of CA between HFT and LFT genotypes. It was shown that significant differences in profiles of protein accumulation between the analyzed plants appeared most often on the 5th (18 proteins) and the 7th (19 proteins) day of CA. The proteins derived from 35 (83.3%) spots were successfully identified by the use of MS and chloroplast proteins were shown to be the major group selected as differentially accumulated during CA. The functions of the identified proteins and their probable influence on the level of FT in L. perenne are discussed.
多年生黑麦草（Lolium perenne）是一种优质的饲料和草坪草，主要因其优异的营养价值和快速建立率。然而，该物种在恶劣的冬季气候条件下的适应能力有限。尽管抗寒性是一个复杂的特征，但普遍认为耐霜性（FT）是其主要组成部分。生长在温带地区的物种可以通过暴露在低温、非致死温度下获得 FT，这种现象称为冷驯化（CA）。关于 FT 的分子基础的研究已经在模式植物上进行，但它们不太适应极端的冬季气候。因此，冬季作物和农业上重要的多年生草的细胞对低温的反应机制尚未揭示。在这里，选择了两个具有不同 FT 水平的多年生黑麦草植株，高耐霜性（HFT）和低耐霜性（LFT）植株，进行比较蛋白质组学研究。这项工作集中在 CA 前后 2、8、26 h 和 3、5、7、14 和 21 天叶片蛋白质积累的分析，使用高通量二维电泳，并通过应用质谱法（MS）对所选植物之间差异积累的蛋白质进行鉴定。分析了 580 个蛋白质图谱，共发现了 42 个（7.2%）点，这些点在 HFT 和 LFT 基因型之间的 CA 至少一个时间点的蛋白质丰度至少有 1.5 倍的差异。结果表明，分析植物之间的蛋白质积累图谱差异最常出现在 CA 的第 5 天（18 个蛋白质）和第 7 天（19 个蛋白质）。使用 MS 成功鉴定了来自 35 个（83.3%）点的蛋白质，并且表明叶绿体蛋白质是 CA 期间差异积累的主要选择组。讨论了鉴定的蛋白质的功能及其对多年生黑麦草 FT 水平的可能影响。
