Comprehensive Analysis of ABA Effects on Ethylene Biosynthesis and Signaling during Tomato Fruit Ripening

Abstract

ABA has been widely acknowledged to regulate ethylene biosynthesis and signaling during fruit ripening, but the molecular mechanism underlying the interaction between these two hormones are largely unexplored. In the present study, exogenous ABA treatment obviously promoted fruit ripening as well as ethylene emission, whereas NDGA (Nordihydroguaiaretic acid, an inhibitor of ABA biosynthesis) application showed the opposite biological effects. Combined RNA-seq with time-course RT-PCR analysis, our study not only helped to illustrate how ABA regulated itself at the transcription level, but also revealed that ABA can facilitate ethylene production and response probably by regulating some crucial genes such as LeACS4, LeACO1, GR and LeETR6. In addition, investigation on the fruits treated with 1-MCP immediately after ABA exposure revealed that ethylene might be essential for the induction of ABA biosynthesis and signaling at the onset of fruit ripening. Furthermore, some specific transcription factors (TFs) known as regulators of ethylene synthesis and sensibility (e.g. MADS-RIN, TAGL1, CNR and NOR) were also observed to be ABA responsive, which implied that ABA influenced ethylene action possibly through the regulation of these TFs expression. Our comprehensive physiological and molecular-level analysis shed light on the mechanism of cross-talk between ABA and ethylene during the process of tomato fruit ripening.

Exploring the Functions of 9-Lipoxygenase (DkLOX3) in Ultrastructural Changes and Hormonal Stress Response during Persimmon Fruit Storage

“…In agreement with previous studies, our results showed that application of ABA accelerated persimmon fruit ripening, concomitant with promoting ethylene synthesis and loss of firmness (Figure 1B,D) [38,40,76]. Additionally, exogenous ABA was associated with enhanced transcriptional levels of DkLOX3 during fruit ripening (Figure 5B).…”

“…Additionally, exogenous ABA was associated with enhanced transcriptional levels of DkLOX3 during fruit ripening (Figure 5B). Some evidence has suggested that ethylene and ABA play fairly important roles in the control of fruit ripening [38,40,73,77]. In tomato and peach fruits, ABA promotes ripening by inducing ethylene biosynthesis through the up-regulation of ethylene biosynthesis genes [76].…”

“…ABA is important for plant growth, development and the response to stress conditions and is able to accelerate the ripening process [37]. Numerous studies have shown that ABA is able to promote ethylene production in many fruits, such as mango [38], strawberry [39] and tomato [40], implying that ABA may function as an upstream regulator of ethylene biosynthesis and responses [41]. JAs, such as methyl jasmonate (MeJA), JA, and other derivatives, make the plant responsive to various biotic and abiotic stresses and are involved in fruit ripening [42,43,44,45].…”

Thank You to Reviewers and Monitoring Editors

“…It is unclear how ETR2 is having this effect. It is known that stress and application of ABA can affect the transcript levels of the ethylene receptors in various plant species (Zhao and Schaller, 2004;Martín-Rodríguez et al, 2011;Mou et al, 2016). We were therefore curious to know if application of ABA altered the transcript levels of the five ethylene receptors, and whether loss of either ETR1 or ETR2 affected ABA-induced changes in the other receptors.…”

Transcriptomic Analysis on the Regulation of Tomato Ripening by the Ethylene Inhibitor 1-methylcyclopropene

“…RNA-Seq also allows quantification of the relative alterations of each transcript during defined developmental stages or under specific treatment conditions in plants. For example, RNA-Seq was used to study the regulation of auxin and gibberellin (GA), and the effect of abscisic acid (ABA) on fruit ripening (Mou et al, 2016;Tang et al, 2015;Li et al, 2016;Ye et al, 2015). In this study, RNA-Seq was used to study the transcriptome changes under 1-MCP treatment to understand the effect of 1-MCP on tomato fruit ripening at the genomic level.…”