Modulation of organic acids and sugar content in tomato fruits by an abscisic acid-regulated transcription factor
Modulation of organic acids and sugar content in tomato fruits by an abscisic acid-regulated transcription factor
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DOI：
10.1111/j.1399-3054.2010.01435.x
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发表时间：
2011-03-01
影响因子：
6.4
通讯作者：
Casaretto, Jose A.
中科院分区：
文献类型：
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作者：
Bastias, Adriana;Lopez-Climent, Maria;Casaretto, Jose A.
越来越多的证据表明植物激素脱落酸（阿坝）在果实发育中起作用。发育程序和对胁迫条件的响应的阿坝信号传导组分包括被称为ABA-响应元件结合因子（AREB/ABF）的碱性亮氨酸拉链转录激活因子组。AREB转录因子介导ABA调节的基因表达，参与脱水耐性，并主要在种子和营养组织中表达的压力下，然而，他们也表达在一些水果，如番茄。为了深入了解阿坝信号在果实发育中的作用，研究了两个AREB样因子在果实发育不同阶段的表达。此外，番茄转基因株系，过表达和下调一个AREB样转录因子，SlAREB 1，被用来确定其对一些代谢物的水平决定果实品质的影响。与反义抑制系相比，SlAREB 1过表达系中柠檬酸、苹果酸、谷氨酸、葡萄糖和果糖的含量较高。较高的己糖浓度与编码液泡转化酶（EC 3.2.1.26）和蔗糖合成酶（EC 2.4.1.13）的基因的表达增加相关。乙烯含量没有显着变化，这与转基因果实中观察到的正常成熟表型一致。这些结果表明，一个AREB介导的阿坝信号影响这些化合物在果实发育过程中的代谢。
Growing evidence suggests that the phytohormone abscisic acid (ABA) plays a role in fruit development. ABA signaling components of developmental programs and responses to stress conditions include the group of basic leucine zipper transcriptional activators known as ABA-response element binding factors (AREBs/ABFs). AREB transcription factors mediate ABA-regulated gene expression involved in desiccation tolerance and are expressed mainly in seeds and in vegetative tissues under stress; however, they are also expressed in some fruits such as tomato. In order to get an insight into the role of ABA signaling in fruit development, the expression of two AREB-like factors were investigated during different developmental stages. In addition, tomato transgenic lines that overexpress and downregulate one AREB-like transcription factor, SlAREB1, were used to determine its effect on the levels of some metabolites determining fruit quality. Higher levels of citric acid, malic acid, glutamic acid, glucose and fructose were observed in SlAREB1-overexpressing lines compared with those in antisense suppression lines in red mature fruit pericarp. The higher hexose concentration correlated with increased expression of genes encoding a vacuolar invertase (EC 3.2.1.26) and a sucrose synthase (EC 2.4.1.13). No significant changes were found in ethylene content which agrees with the normal ripening phenotype observed in transgenic fruits. These results suggest that an AREB-mediated ABA signal affects the metabolism of these compounds during the fruit developmental program.