Table_1_Metabolomic and transcriptomic analyses reveal the mechanism of sweet-acidic taste formation during pineapple fruit development.XLSX

Pineapple (Ananas comosus L.) is one of the most valuable subtropical fruit crop in the world. The sweet-acidic taste of the pineapple fruits is a major contributor to the characteristic of fruit quality, but its formation mechanism remains elusive. Here, targeted metabolomic and transcriptomic analyses were performed during the fruit developmental stages in two pineapple cultivars (“Comte de Paris” and “MD-2”) to gain a global view of the metabolism and transport pathways involved in sugar and organic acid accumulation. Assessment of the levels of different sugar and acid components during fruit development revealed that the predominant sugar and organic acid in mature fruits of both cultivars was sucrose and citric acid, respectively. Weighted gene coexpression network analysis of metabolic phenotypes and gene expression profiling enabled the identification of 21 genes associated with sucrose accumulation and 19 genes associated with citric acid accumulation. The coordinated interaction of the 21 genes correlated with sucrose irreversible hydrolysis, resynthesis, and transport could be responsible for sucrose accumulation in pineapple fruit. In addition, citric acid accumulation might be controlled by the coordinated interaction of the pyruvate-to-acetyl-CoA-to-citrate pathway, gamma-aminobutyric acid pathway, and tonoplast proton pumps in pineapple. These results provide deep insights into the metabolic regulation of sweetness and acidity in pineapple.

菠萝（Ananas comosus L.）乃全球最具价值的亚热带水果作物之一。菠萝果实之甜美与酸涩之味，为果实品质之特征性贡献良多，然而其形成机制却始终难以捉摸。本研究针对两种菠萝品种（“巴黎伯爵”与“MD-2”）在果实发育阶段，进行了靶向代谢组学和转录组学分析，以期全面了解糖分与有机酸积累所涉及的代谢与运输途径。对果实发育过程中不同糖分与酸分成分水平的评估显示，两种品种成熟果实中的主要糖分与有机酸分别为蔗糖与柠檬酸。通过对代谢表型与基因表达谱的加权基因共表达网络分析，成功识别出与蔗糖积累相关的21个基因以及与柠檬酸积累相关的19个基因。这21个基因的协调相互作用与菠萝果实中蔗糖的不可逆水解、再合成及运输相关，可能负责蔗糖的积累。此外，柠檬酸的积累可能受菠萝中丙酮酸至乙酰辅酶A至柠檬酸的途径、γ-氨基丁酸途径以及质膜质子泵的协调作用所调控。本研究结果为菠萝甜味与酸味代谢调节提供了深刻的见解。