Chen Hongying, Osuna Daniel, Colville Louise, Lorenzo Oscar, Graeber Kai, Küster Helge, Leubner-Metzger Gerhard, Kranner Ilse
Plant Germplasm and Genomics Center, Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, People's Republic of China ; Seed Conservation Department, Royal Botanic Gardens, Kew, Ardingly, West Sussex, United Kingdom.
PLoS One. 2013 Oct 29;8(10):e78471. doi: 10.1371/journal.pone.0078471. eCollection 2013.
Understanding of seed ageing, which leads to viability loss during storage, is vital for ex situ plant conservation and agriculture alike. Yet the potential for regulation at the transcriptional level has not been fully investigated. Here, we studied the relationship between seed viability, gene expression and glutathione redox status during artificial ageing of pea (Pisum sativum) seeds. Transcriptome-wide analysis using microarrays was complemented with qRT-PCR analysis of selected genes and a multilevel analysis of the antioxidant glutathione. Partial degradation of DNA and RNA occurred from the onset of artificial ageing at 60% RH and 50°C, and transcriptome profiling showed that the expression of genes associated with programmed cell death, oxidative stress and protein ubiquitination were altered prior to any sign of viability loss. After 25 days of ageing viability started to decline in conjunction with progressively oxidising cellular conditions, as indicated by a shift of the glutathione redox state towards more positive values (>-190 mV). The unravelling of the molecular basis of seed ageing revealed that transcriptome reprogramming is a key component of the ageing process, which influences the progression of programmed cell death and decline in antioxidant capacity that ultimately lead to seed viability loss.
了解种子老化（这会导致种子在储存期间丧失活力）对于迁地植物保护和农业而言都至关重要。然而，转录水平调控的潜力尚未得到充分研究。在此，我们研究了豌豆（Pisum sativum）种子人工老化过程中种子活力、基因表达和谷胱甘肽氧化还原状态之间的关系。使用微阵列进行的全转录组分析辅以对选定基因的qRT-PCR分析以及对抗氧化谷胱甘肽的多层次分析。在60%相对湿度和50°C的人工老化开始时，DNA和RNA就出现了部分降解，转录组分析表明，与程序性细胞死亡、氧化应激和蛋白质泛素化相关的基因表达在活力丧失的任何迹象出现之前就发生了改变。老化25天后，活力开始下降，同时细胞状况逐渐氧化，这表现为谷胱甘肽氧化还原状态向更正的值（>-190 mV）转变。对种子老化分子基础的揭示表明，转录组重编程是老化过程的关键组成部分，它影响程序性细胞死亡的进程以及抗氧化能力的下降，最终导致种子活力丧失。
