ABSTRACT

The phytohormones jasmonates (JAs) act as important molecules of elicitors for the chlorophyll degradation and anthocyanin biosynthesis. JAs do usually not act independently but integrate in complex networks linking to other hormonal signaling transduction. Here, the crosstalk was detected between the JAs (jasmonic acid) and abscisic acid (ABA) signaling pathways in the mediation of chlorophyll degradation and anthocyanin biosynthesis. In this study, we found that the ABA receptor mutants, pyr1pyl1pyl2pyl4 (1124) and pyr1pyl1ply2pyl4pyl5pyl8 (112458) showed less level of chlorophyll and anthocyanin than the wild-type plants, while gain-of-function of RCAR13 transgenic lines inhibited chlorophyll degradation and enhanced anthocyanin accumulation after MeJA treatment. The amidohydrolases, including ILL6 and IAR3 and cytochrome P450 (CYP94B3), encoding JA-Ile catabolism were markedly depressed by ABA receptors. While transcripts of the enzymes for activation of anthocyanin biosynthesis pathway were analyzed, the results indicating that JA biosynthetic genes, including allene oxide synthase (AOS), LOX3 and LOX4 were enhanced by the link of JAs and ABA receptors. Moreover, the ABA receptors are also involved in JAs signal transduction through the regulation of COI, JAZ and MYC2 transcripts. These findings elucidate a connection between a core component of the ABA signaling pathway and JA responses.

摘要

茉莉酸植物激素 (JAs) 是叶绿素降解和花青素生物合成的重要诱导剂分子。JA 通常不会独立发挥作用，而是集成在连接到其他激素信号转导的复杂网络中。在这里，在介导叶绿素降解和花青素生物合成的 JA（茉莉酸）和脱落酸（ABA）信号通路之间检测到串扰。在这项研究中，我们发现 ABA 受体突变体pyr1pyl1pyl2pyl4 (1124) 和pyr1pyl1ply2pyl4pyl5pyl8 (112458) 的叶绿素和花青素水平低于野生型植物，而RCAR13的功能获得转基因品系在 MeJA 处理后抑制叶绿素降解并增强花青素积累。ABA 受体显着抑制了编码 JA-Ile 分解代谢的酰胺水解酶，包括ILL6和IAR3以及细胞色素 P450 ( CYP94B3 )。虽然分析了激活花青素生物合成途径的酶的转录本，但结果表明JA生物合成基因，包括丙二烯氧化物合酶（AOS）、LOX3和LOX4通过JAs和ABA受体的连接而得到增强。此外，ABA 受体还通过COI、JAZ和MYC2的调节参与 JAs 信号转导。成绩单。这些发现阐明了 ABA 信号通路的核心成分与 JA 反应之间的联系。