PacPP2CA在光诱导黄色甜樱桃果实花色苷合成中的作用及其机理解析

光对不同色泽甜樱桃果实花色苷合成的影响不同，其中黄色甜樱桃果实着色高度依赖于光，其着红晕后的果实具有更高的商品价值。我们的研究显示，PacPP2CA的表达在黄色品种中受光显著诱导，并可极显著提高PacUFGT启动子活性，表明其参与光诱导的黄色甜樱桃果实花色苷合成；同时光和ABA叠加处理显著促进黄色甜樱桃果实着色，且PacPP2CA参与该过程。PacPP2CA为典型的ABA信号组分，其参与光和ABA协同调控黄色甜樱桃果实着色机理尚不清楚。为此，本研究以黄色甜樱桃果实为试材，拟在明确PacPP2CA功能基础上，利用蛋白互作技术深入挖掘光和ABA共同诱导的PacPP2CA互作蛋白；通过VIGS和原生质体转化技术，明确互作蛋白中参与光和ABA协同调控果实着色的核心组分；进而结合双荧光素酶报告系统和稳定转化技术，揭示PacPP2CA参与光和ABA协同调控黄色甜樱桃果实花色苷合成的信号通路和分子机理。

Anthocyanin accumulation level directly determines the appearance quality of bicolored sweet cherry (Prunus avium L) fruits. Our previous work has proved that light plays a major role in determining the pigment accumulation of the bicolored cherries, but not in that of the dark-red ones. The expression of PacPP2CA gene was specifically induced by light in bicolored cherries, and the promoter activity of anthocyanin biosynthetic gene PacUFGT could be improved by this gene under light conditions, which suggested that PacPP2CA was involved in the light-induced color formation of bicolored sweet cherry fruits. Combined with previous reports and our researches, light and ABA co-treatment significantly promoted the anthocyanin accumulation in bicolored cherry fruits, and PacPP2CA was involved in this process, but the regulatory mechanism of PacPP2CA in anthocyanin biosynthesis of bicolored cherries by integrating the light and ABA signal is still unclear. Therefore, in this study, the bicolored cultivars are used as the experimental materials to explore the light and ABA signaling core components which interacted with PacPP2CA by using the protein-protein interaction technology. Then, VIGS and protoplast transformation assays will be performed to characterize their biological function of candidate genes. Furthermore, stable genetic transformation system will be conducted to determine the signaling network of PacPP2CA-mediated crosstalk of the light and ABA signals in anthocyanin biosynthesis of bicolored cherries. This study aims to elucidate the molecular mechanism of PacPP2CA involved in fruit coloration of bicolored sweet cherries under light and ABA co-treatment.