Effects of vitro sucrose on quality components of tea plants (Camellia sinensis) based on transcriptomic and metabolic analysis

• Published in: BMC plant biology Vol. 18; no. 1; pp. 121 - 20
• Main Authors: Qian, Yumei, Zhang, Shuxiang, Yao, Shengbo, Xia, Jinxin, Li, Yanzhi, Dai, Xinlong, Wang, Wenzhao, Jiang, Xiaolan, Liu, Yajun, Li, Mingzhuo, Gao, Liping, Xia, Tao
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 18.06.2018; BioMed Central; BMC
• Subjects: Abiotic factors; Abiotic stress; Acids; Alcoholic beverages; Allelochemicals; Analysis; Anthocyanins; Aroma; Aromatic compounds; ATP-binding protein; Beverages; Biosynthesis; Camellia sinensis; Camellia sinensis - drug effects; Camellia sinensis - genetics; Camellia sinensis - metabolism; Camellia sinensis, Polyphenol biosynthesis, Volatile; Catechin; Chemical composition; Composition; Derivatives; Epicatechin; Extrusion; Flavonoids; Flavor; Gene expression; Gene Expression Profiling; Gene Expression Regulation, Plant - drug effects; Genes; Genes, Plant - genetics; Genetic aspects; Genetic transcription; Genomics; Glutathione; Glutathione transferase; Liquid chromatography; Mass spectrometry; Mass spectroscopy; Metabolism; Metabolomics; Molecular chains; Molecular modelling; Plants (botany); Polyphenols; Polyphenols - metabolism; Proanthocyanidins; Quadrupoles; Real-Time Polymerase Chain Reaction; Signal transduction; Sucrose; Sucrose - metabolism; Sucrose - pharmacology; Sucrose induction; Sugar; Tea; Tea (Plant); Transcription factors; Transcription Factors - metabolism; Transcriptomic and metabolic analysis; Volatile compounds; Volatile Organic Compounds - metabolism; Volatiles; Japan; China; India; Camellia sinensis, Polyphenol biosynthesis, Volatile; Sucrose induction; Transcriptomic and metabolic analysis
• ISSN: 1471-2229; 1471-2229
• DOI: 10.1186/s12870-018-1335-0

Tea plants [Camellia sinensis (L.) O. Kuntze] can produce one of the three most widely popular non-alcoholic beverages throughout the world. Polyphenols and volatiles are the main functional ingredients determining tea's quality and flavor; however, the biotic or abiotic factors affecting tea polyphenol biosynthesis are unclear. This paper focuses on the molecular mechanisms of sucrose on polyphenol biosynthesis and volatile composition variation in tea plants. Metabolic analysis showed that the total content of anthocyanins, catechins, and proanthocyanidins(PAs) increased with sucrose, and they accumulated most significantly after 14 days of treatment. Transcriptomic analysis revealed 8384 and 5571 differentially expressed genes in 2-day and 14-day sucrose-treated tea plants compared with control-treated plants. Most of the structural genes and transcription factors (TFs) involved in polyphenol biosynthesis were significantly up-regulated after 2d. Among these transcripts, the predicted genes encoding glutathione S-transferase (GST), ATP-binding cassette transporters (ABC transporters), and multidrug and toxic compound extrusion transporters (MATE transporters) appeared up regulated. Correspondingly, ultra-performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-QQQ-MS/MS) analysis revealed that the content of non-galloylated catechins and oligomeric PAs decreased in the upper-stem and increased in the lower-stem significantly, especially catechin (C), epicatechin (EC), and their oligomeric PAs. This result suggests that the related flavonoids were transported downward in the stem by transporters. GC/MS data implied that four types of volatile compounds, namely terpene derivatives, aromatic derivatives, lipid derivatives, and others, were accumulated differently after in vitro sucrose treatment. Our data demonstrated that sucrose regulates polyphenol biosynthesis in Camellia sinensis by altering the expression of transcription factor genes and pathway genes. Additionally, sucrose promotes the transport of polyphenols and changes the aroma composition in tea plant.