DataSheet_1_Gibberellin delays metabolic shift during tomato ripening by inducing auxin signaling.docx

Fruit ripening involves the dynamic interaction of phytohormones. Ethylene (ET) and gibberellin (GA) antagonistically affect fruit ripening. However, the mechanism of GA and its potential interaction with ET during fruit ripening remain unknown. To identify the potential molecular mechanism of ET and GA interplay in tomato (Solanum lycopersicum L.) fruit ripening, transcriptome and metabolomic profiling was carried out in tomato fruit treated with GA, ET or the combination of the two hormones (GA+ET). ET accelerated fruit ripening with the simultaneous repression of auxin signaling. In contrast, gibberellin delayed ripening by the upregulation of auxin signaling. ET signaling and response was inhibited by GA or combined with ET. At the metabolite level, while GA treatment inhibited metabolite shift during ripening, ET treatment promoted. In the combined hormone treatment, ET reduced or recovered GA inhibitory effect on specific metabolites. This study provided insight into ET and GA interaction, highlighting the importance of auxin signaling in metabolic shifts during tomato ripening progression.

果实成熟过程伴随植物激素间的动态互作。乙烯（Ethylene, ET）与赤霉素（Gibberellin, GA）拮抗调控果实成熟。然而，赤霉素的作用机制及其与乙烯在果实成熟过程中的潜在互作关系尚未阐明。为解析番茄（Solanum lycopersicum L.）果实成熟过程中乙烯与赤霉素的互作分子机制，本研究对经赤霉素、乙烯或二者联合处理（GA+ET）的番茄果实开展了转录组（transcriptome）与代谢组学（metabolomic）分析。结果显示，乙烯可加速果实成熟，同时抑制生长素（auxin）信号通路；与之相反，赤霉素通过上调生长素信号通路延缓果实成熟。赤霉素单独处理或与乙烯联合处理时，均可抑制乙烯信号通路及其下游响应过程。在代谢层面，赤霉素处理会抑制果实成熟过程中的代谢物动态变化，而乙烯处理则可促进该变化；在激素联合处理组中，乙烯可减弱甚至逆转赤霉素对特定代谢物的抑制作用。本研究阐明了乙烯与赤霉素的互作机制，同时凸显了生长素信号通路在番茄果实成熟进程中代谢物动态变化过程中的关键调控作用。