Department of Biosciences, Università degli Studi di Milano, Milan, Italy.
J Exp Bot. 2019 Jun 1;70(11):2993-3006. doi: 10.1093/jxb/erz112.
Fruits result from complex biological processes that begin soon after fertilization. Among these processes are cell division and expansion, accumulation of secondary metabolites, and an increase in carbohydrate biosynthesis. Later fruit ripening is accomplished by chlorophyll degradation and cell wall lysis. Fruit maturation is an essential step to optimize seed dispersal, and is controlled by a complex network of transcription factors and genetic regulators that are strongly influenced by phytohormones. Abscisic acid (ABA) and ethylene are the major regulators of ripening and senescence in both dry and fleshy fruits, as demonstrated by numerous ripening-defective mutants, effects of exogenous hormone application, and transcriptome analyses. While ethylene is the best characterized player in the final step of a fruit's life, ABA also has a key regulatory role, promoting ethylene production and acting as a stress-related hormone in response to drought and pathogen attack. In this review, we focus on the role of ABA and ethylene in relation to the interconnected biotic and abiotic phenomena that affect ripening and senescence. We integrate and discuss the most recent data available regarding these biological processes, which are crucial for post-harvest fruit conservation and for food safety.
水果是复杂的生物学过程的产物,这些过程在受精后不久就开始了。这些过程包括细胞分裂和扩张、次生代谢物的积累以及碳水化合物生物合成的增加。随后,果实的成熟是通过叶绿素的降解和细胞壁的溶解来实现的。果实成熟是优化种子传播的关键步骤,受转录因子和遗传调控因子的复杂网络控制,这些因子受植物激素的强烈影响。脱落酸(ABA)和乙烯是干果和肉质果实成熟和衰老的主要调节剂,这可以通过大量的成熟缺陷突变体、外源激素应用的影响以及转录组分析来证明。虽然乙烯是果实生命的最后阶段中最具特征的参与者,但 ABA 也具有关键的调节作用,它促进乙烯的产生,并作为一种与应激相关的激素,对干旱和病原体的攻击做出反应。在这篇综述中,我们重点关注 ABA 和乙烯在与影响成熟和衰老的生物和非生物现象的相互关系中的作用。我们整合和讨论了关于这些生物学过程的最新数据,这些数据对于采后水果的保存和食品安全至关重要。