Rajjou Loïc, Lovigny Yoann, Groot Steven P C, Belghazi Maya, Job Claudette, Job Dominique
UMR 204, INRA-AgroParisTech, Laboratoire de Biologie des Semences, AgroParisTech, Chaire de Physiologie Végétale, F-75231 Paris cedex 05, France.
Plant Physiol. 2008 Sep;148(1):620-41. doi: 10.1104/pp.108.123141. Epub 2008 Jul 3.
A variety of mechanisms have been proposed to account for the extension of life span in seeds (seed longevity). In this work, we used Arabidopsis (Arabidopsis thaliana) seeds as a model and carried out differential proteomics to investigate this trait, which is of both ecological and agricultural importance. In our system based on a controlled deterioration treatment (CDT), we compared seed samples treated for different periods of time up to 7 d. Germination tests showed a progressive decrease of germination vigor depending on the duration of CDT. Proteomic analyses revealed that this loss in seed vigor can be accounted for by protein changes in the dry seeds and by an inability of the low-vigor seeds to display a normal proteome during germination. Furthermore, CDT strongly increased the extent of protein oxidation (carbonylation), which might induce a loss of functional properties of seed proteins and enzymes and/or enhance their susceptibility toward proteolysis. These results revealed essential mechanisms for seed vigor, such as translational capacity, mobilization of seed storage reserves, and detoxification efficiency. Finally, this work shows that similar molecular events accompany artificial and natural seed aging.
人们已经提出了多种机制来解释种子寿命延长（种子活力）的现象。在这项研究中，我们以拟南芥种子为模型，开展了差异蛋白质组学研究以探究这一具有生态和农业重要性的性状。在我们基于控制劣变处理（CDT）的体系中，我们比较了长达7天不同处理时间的种子样本。发芽试验表明，发芽活力随着CDT处理时间的延长而逐渐下降。蛋白质组学分析显示，种子活力的丧失可归因于干种子中的蛋白质变化以及低活力种子在萌发过程中无法展现正常的蛋白质组。此外，CDT显著增加了蛋白质氧化（羰基化）的程度，这可能导致种子蛋白质和酶功能特性的丧失和/或增强其对蛋白水解的敏感性。这些结果揭示了种子活力的重要机制，如翻译能力、种子贮藏物质的动员和解毒效率。最后，这项研究表明，人工和自然种子老化伴随着相似的分子事件。
