Transcriptomic and phytochemical analysis of the biosynthesis of characteristic constituents in tea (Camellia sinensis) compared with oil tea (Camellia oleifera)

BMC Plant Biology

Research Article

Chitang Ho¹  Jing Zhang²  Congbing Fang²  Shu Wei²  Yuling Tai²  Hua Yang²  Weiwei Deng²  Liang Zhang²  Chaoling Wei²  Qi Chen²  Xiaochun Wan² 

[1] Department of Food Science, Rutgers University, Rutgers, NJ, USA;State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 230036, Hefei, People’s Republic of China;

关键词: Comparative transcriptome;    Camellia sinensis;    Camellia oleifera;    Chemical constituents;    Metabolic pathways;   

DOI  :  10.1186/s12870-015-0574-6

 received in 2015-03-01, accepted in 2015-07-17,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundTea plants (Camellia sinensis) are used to produce one of the most important beverages worldwide. The nutritional value and healthful properties of tea are closely related to the large amounts of three major characteristic constituents including polyphenols (mainly catechins), theanine and caffeine. Although oil tea (Camellia oleifera) belongs to the genus Camellia, this plant lacks these three characteristic constituents. Comparative analysis of tea and oil tea via RNA-Seq would help uncover the genetic components underlying the biosynthesis of characteristic metabolites in tea.ResultsWe found that 3,787 and 3,359 bud genes, as well as 4,042 and 3,302 leaf genes, were up-regulated in tea and oil tea, respectively. High-performance liquid chromatography (HPLC) analysis revealed high levels of all types of catechins, theanine and caffeine in tea compared to those in oil tea. Activation of the genes involved in the biosynthesis of these characteristic compounds was detected by RNA-Seq analysis. In particular, genes encoding enzymes involved in flavonoid, theanine and caffeine pathways exhibited considerably different expression levels in tea compared to oil tea, which were also confirmed by quantitative RT-PCR (qRT-PCR).ConclusionWe assembled 81,826 and 78,863 unigenes for tea and oil tea, respectively, based on their differences at the transcriptomic level. A potential connection was observed between gene expression and content variation for catechins, theanine and caffeine in tea and oil tea. The results demonstrated that the metabolism was activated during the accumulation of characteristic metabolites in tea, which were present at low levels in oil tea. From the molecular biological perspective, our comparison of the transcriptomes and related metabolites revealed differential regulatory mechanisms underlying secondary metabolic pathways in tea versus oil tea.

【 授权许可】

CC BY   
© Tai et al. 2015