College of Agronomy, Jiangxi Agricultural University, Nanchang 330045, China.
Institute of Kiwifruit, Jiangxi Agricultural University, Nanchang 330045, China.
Int J Mol Sci. 2022 Sep 6;23(18):10217. doi: 10.3390/ijms231810217.
is a unique germplasm resource for kiwifruit breeding. Genetic diversity and nutrient content need to be evaluated prior to breeding. In this study, we looked at the metabolites of three elite varieties (MM-11, MM-13 and MM-16) selected from natural individuals by using a UPLC-MS/MS-based metabolomics approach and transcriptome, with a total of 417 metabolites identified. The biosynthesis and metabolism of phenolic acid, flavonoids, sugars, organic acid and AsA in fruit were further analyzed. The phenolic compounds accounted for 32.37% of the total metabolites, including 48 phenolic acids, 60 flavonoids, 7 tannins and 20 lignans and coumarins. Correlation analysis of metabolites and transcripts showed (), ( and D), (), () and () correlated with polyphenols. There are twenty-three metabolites belonging to sugars, the majority being sucrose, glucose arabinose and melibiose. The starch biosynthesis-related genes (, and ) were expressed at lower levels compared with metabolism-related genes (a and ) in three mature fruits of three varieties, indicating that starch was converted to soluble sugar during fruit maturation, and the expression level of () and () was correlated with trehalose 6-phosphate. The main organic acids in fruit are citric acid, quinic acid, succinic acid and D-xylonic acid. Correlation analysis of metabolites and transcripts showed () was highly correlated with citric acid, () with oxaloacetic acid, and () with malic acid. Based on the gene expression, the metabolism of AsA acid was primarily through the L-galactose pathway, and the expression level of () and () highly correlated with L-Ascorbic acid. Our study provides additional evidence for the correlation between the genes and metabolites involved in phenolic acid, flavonoids, sugars, organic acid and AsA synthesis and will help to accelerate the kiwifruit molecular breeding approaches.
是猕猴桃育种的独特种质资源。在进行育种之前，需要评估其遗传多样性和营养成分。在这项研究中，我们使用基于 UPLC-MS/MS 的代谢组学方法和转录组，对从自然个体中选择的三个优良品种（MM-11、MM-13 和 MM-16）的代谢物进行了研究，共鉴定出 417 种代谢物。进一步分析了果实中酚酸、类黄酮、糖、有机酸和 AsA 的生物合成和代谢。酚类化合物占总代谢物的 32.37%，包括 48 种酚酸、60 种类黄酮、7 种单宁和 20 种木脂素和香豆素。代谢物和转录物的相关分析表明，()、()和()与多酚相关。属于糖的二十三种代谢物，其中大部分是蔗糖、葡萄糖阿拉伯糖和棉子糖。三个品种三个成熟果实中，淀粉生物合成相关基因()、()和()的表达水平低于代谢相关基因()和()，表明淀粉在果实成熟过程中转化为可溶糖，()和()的表达水平与海藻糖 6-磷酸相关。猕猴桃果实中的主要有机酸是柠檬酸、奎宁酸、琥珀酸和 D-木酮糖。代谢物和转录物的相关分析表明，()与柠檬酸高度相关，()与草酰乙酸相关，()与苹果酸相关。基于基因表达，AsA 酸的代谢主要通过 L-半乳糖途径，()和()的表达水平与 L-抗坏血酸高度相关。本研究为酚酸、类黄酮、糖、有机酸和 AsA 合成涉及的基因和代谢物之间的相关性提供了更多证据，并将有助于加速猕猴桃的分子育种方法。
