Abscisic acid and sucrose regulate tomato and strawberry fruit ripening through the abscisic acid‐stress‐ripening transcription factor

Abstract

SummaryAlthough great progress has been made towards understanding the role of abscisic acid (ABA) and sucrose in fruit ripening, the mechanisms underlying the ABA and sucrose signalling pathways remain elusive. In this study, transcription factor ABA‐stress‐ripening (ASR), which is involved in the transduction of ABA and sucrose signalling pathways, was isolated and analysed in the nonclimacteric fruit, strawberry and the climacteric fruit, tomato. We have identified four ASR isoforms in tomato and one in strawberry. All ASR sequences contained the ABA stress‐ and ripening‐induced proteins and water‐deficit stress‐induced proteins (ABA/WDS) domain and all ASR transcripts showed increased expression during fruit development. The expression of the ASR gene was influenced not only by sucrose and ABA, but also by jasmonic acid (JA) and indole‐3‐acetic acid (IAA), and these four factors were correlated with each other during fruit development. ASR bound the hexose transporter (HT) promoter, which contained a sugar box that activated downstream gene expression. Overexpression of the ASR gene promoted fruit softening and ripening, whereas RNA interference delayed fruit ripening, as well as affected fruit physiological changes. Change in ASR gene expression influenced the expression of several ripening‐related genes such as CHS,CHI, F3H,DFR,ANS,UFGT,PG,PL,EXP1/2,XET16, Cel1/2 and PME. Taken together, this study may provide new evidence on the important role of ASR in cross‐signalling between ABA and sucrose to regulate tomato and strawberry fruit ripening. The findings of this study also provide new insights into the regulatory mechanism underlying fruit development.

A Histone Code Reader and a Transcriptional Activator Interact to Regulate Genes for Salt Tolerance

“…This protein is usually associated with ABA transduction and fruit ripening (Jia et al, 2016). ASR genes are also stress-responsive genes (Yang et al, 2005;Arenhart et al, 2013).…”

Sugar content analysis and expression profiling of sugar related genes in contrasting Strawberry (Fragaria × ananassa) cultivars

“…These genes regulates the sugar metabolism, biosynthesis of hormones and ripening during the fruit development and growth (Jia et al 2016;Zhongjie et al 2016). Identifying the genes related to biosynthesis of total soluble sugars, glucose, sucrose and fructose would be helpful to widen our understanding on the variation in the biosynthesis of sugar in different cultivars and to identify the novel candidates as points of interventions for breeding programs.…”

“…Among the various sugar compounds, sucrose dominated the sugar profile and thus genes that are involved in sucrose content will be very important candidate for any breeding program to develop high sugar containing strawberry cultivars (Jia et al 2013;Jia et al 2016). Among the 18 sucrose related genes studied, eight genes showed higher expression in high sugar content cultivars compared to the low sugar content cultivars.…”

“…Sucrose plays an important role in fruit ripening by regulation of ripening-related genes (Jia et al 2013). In addition, the sucrose and glucose induces the biosynthesis of ABA which is regulating the strawberry fruit development by regulating the ripening related genes (Jia et al 2013;Jia et al 2016). Therefore, the soluble sugars and major carbohydrates including sucrose, glucose and fructose are among the major determinants of the growth, development, sweetness and overall quality of the strawberry fruits.…”

Ethylene Role in Plant Growth, Development and Senescence: Interaction with Other Phytohormones

“…ABA application increases all hydrolases, which can enhance the softening, with exception to the polygalacturonase activity (Lohani et al, 2004). Recently, it has been reported that an ABA Stress Ripening (ASR) transcription factor acts as a downstream component of a common transduction pathway for ABA and sucrose signals during fruit ripening (Jia et al, 2016). Interestingly, these authors provide new insights into the regulatory mechanism underlying tomato fruit development and ripening with the ethylene involved in the downstream signal transduction of ABA and sucrose, as a negative regulator of ASR gene expression, which influenced the expression of several cell wall and ripening-related genes leading to fruit softening.…”