Laboratoire des Interactions Plantes-Microorganismes (LIPM), Université de Toulouse, INRA, CNRS, INSA, Castanet-Tolosan, France.
J Exp Bot. 2019 Aug 29;70(17):4419-4427. doi: 10.1093/jxb/erz117.
Senescence is a regulated process of tissue degeneration that can affect any plant organ and consists of the degradation and remobilization of molecules to other growing tissues. Senescent organs display changes at the microscopic level as well as modifications to internal cellular structure and differential gene expression. A large number of factors influencing senescence have been described including age, nutrient supply, and environmental interactions. Internal factors such as phytohormones also affect the timing of leaf senescence. A link between the senescence process and the production of nitric oxide (NO) in senescing tissues has been known for many years. Remarkably, this link can be either a positive or a negative correlation depending upon the organ. NO can be both a signaling or a toxic molecule and is known to have multiple roles in plants; this review considers the duality of NO roles in the senescence process of two different plant organs, namely the leaves and root nodules.
衰老是一种组织退化的调控过程，它可以影响任何植物器官，包括分子的降解和再动员到其他生长组织中。衰老器官在微观水平上表现出变化，以及内部细胞结构和差异基因表达的改变。大量影响衰老的因素已经被描述，包括年龄、营养供应和环境相互作用。内部因素，如植物激素，也会影响叶片衰老的时间。多年来，人们已经知道衰老过程与衰老组织中一氧化氮（NO）的产生之间存在联系。值得注意的是，这种联系可以是正相关或负相关，这取决于器官。NO 既可以是一种信号分子，也可以是一种有毒分子，并且已知在植物中有多种作用；本综述考虑了 NO 在两种不同植物器官（叶片和根瘤）衰老过程中的双重作用。
