Hu Haichao, Fei Xitong, He Beibei, Chen Xin, Ma Lei, Han Peilin, Luo Yingli, Liu Yonghong, Wei Anzhi
College of Forestry, Northwest Agriculture and Forestry University, Xianyang, China.
Research Centre for Engineering and Technology of Zanthoxylum State Forestry Administration, Xianyang, China.
Front Nutr. 2022 Jul 7;9:921742. doi: 10.3389/fnut.2022.921742. eCollection 2022.
leaves have a unique taste and incomparable nutritional value and hence are popular as a food item and traditional medicine in China. However, the studies on the metabolites in leaves are quite limited, especially for amino acids. Therefore, this study explored the amino acid component in leaves and also the accumulation mechanism under drought stress in two cultivars using the widely targeted metabolome combined with transcriptome analysis. A total of 56 amino acids and their derivatives were identified in leaves, including eight essential amino acids. The total amino acid content with most individual amino acids increased under progressive drought stress. More differentially accumulated amino acids (DAAs) and differentially expressed genes (DEGs) were found in FJ ( cv. 'Fengjiao') than in HJ ( cv. 'Hanjiao'). The orthogonal projections to latent structures discriminant analysis identified nine and seven indicator DAAs in FJ and HJ leaves, respectively. The weighted gene co-expression network analysis (WGCNA) showed that the green module was significantly correlated with most indicator DAAs and revealed the important role of , and 15 transcription factor genes in regulating the amino acid synthesis. Furthermore, the correlation analysis and redundancy analysis (RDA) identified four candidate synthesis genes (, , , and ) in amino acid biosynthesis pathway. This study provided useful information for the development of leaves in food and nutrition industry and also laid the foundations for future molecular breeding.
叶具有独特的风味和无与伦比的营养价值，因此在中国作为食品和传统药物广受欢迎。然而，关于叶中代谢物的研究相当有限，尤其是氨基酸方面。因此，本研究利用广泛靶向代谢组学结合转录组分析，探究了两个品种叶中的氨基酸成分以及干旱胁迫下的积累机制。在叶中共鉴定出56种氨基酸及其衍生物，包括8种必需氨基酸。随着干旱胁迫加剧，总氨基酸含量以及大多数单个氨基酸的含量均增加。与HJ（品种‘汉椒’）相比，FJ（品种‘凤椒’）中发现了更多差异积累氨基酸（DAA）和差异表达基因（DEG）。正交投影到潜在结构判别分析分别在FJ和HJ叶中鉴定出9个和7个指示性DAA。加权基因共表达网络分析（WGCNA）表明，绿色模块与大多数指示性DAA显著相关，并揭示了[具体基因名称1]、[具体基因名称2]和15个转录因子基因在调节氨基酸合成中的重要作用。此外，相关性分析和冗余分析（RDA）在氨基酸生物合成途径中鉴定出4个候选合成基因（[具体基因名称3]、[具体基因名称4]、[具体基因名称5]和[具体基因名称6]）。本研究为叶在食品和营养工业中的开发提供了有用信息，并为未来的分子育种奠定了基础。
