The regulation of apple (Malus domestica) fruit texture during ripening is complex and a fundamental determinant of its commercial quality. In climacteric fruit, ripening-related processes are regulated by ethylene (ET), and jasmonate (JA) is also involved in the ethylene biosynthesis pathway, mainly through the transcription factor MYC2. However, the molecular genetic mechanism for fruit ripening processes between the JA and ET signaling pathways still needs to be elucidated. In order to explore how JA regulates apple fruit ripening through ERF4, we used ‘Gala’ and ‘Ralls Janet’ fruit at different developmental stages as experimental materials to determine the fruit firmness and related gene expression analysis. Meanwhile, we carried out different hormone treatments on ‘Gala’ fruit at ripening stage. Here, we show that ERF4 is a core JA signaling hub protein JASMONATE ZIM-DOMAIN (JAZ) interactor that affects ethylene signaling pathways. During fruit development, ERF4 represses the expression of ACS1 and ACO1 by interacting with JAZ, as well as with the JA-activated transcription factor MYC2. Ripening is promoted in JAZ-suppressed apples. Thus, ERF4 acts as a molecular link between ethylene and JA hormone signals, and the natural variation of the ERF4 Ethylene-responsive binding factor-associated amphiphilic repression (EAR) motif decreases repression of ethylene biosynthesis genes.

苹果（Malus domestica) 成熟期间的果实质地复杂，是其商业品质的基本决定因素。在跃变型果实中，成熟相关过程受乙烯（ET）调控，茉莉酸（JA）也参与乙烯生物合成途径，主要通过转录因子MYC2。然而，JA 和 ET 信号通路之间的果实成熟过程的分子遗传机制仍需要阐明。为了探究JA如何通过ERF4调控苹果果实成熟，我们以不同发育阶段的'Gala'和'Ralls Janet'果实为试验材料，对果实硬度进行测定并进行相关基因表达分析。同时，我们对‘嘎啦’果实在成熟期进行了不同的激素处理。这里，我们表明 ERF4 是影响乙烯信号通路的核心 JA 信号转导中枢蛋白 JASMONATE ZIM-DOMAIN (JAZ) 相互作用子。在果实发育过程中，ERF4 抑制ACS1和ACO1通过与 JAZ 以及 JA 激活的转录因子 MYC2 相互作用。在 JAZ 抑制的苹果中促进成熟。因此，ERF4 充当乙烯和 JA 激素信号之间的分子连接，ERF4 乙烯响应结合因子相关两亲抑制 (EAR) 基序的自然变异减少了乙烯生物合成基因的抑制。