Functional Analysis of Two Flavanone-3-Hydroxylase Genes from Camellia sinensis: A Critical Role in Flavonoid Accumulation

Genes

Liping Gao¹  Yajun Liu¹  Keyi Huang¹  Tianming Jiao²  Xinlong Dai²  Peiqiang Wang²  Yumei Qian²  Yahui Han²  Guoliang Ma²  Tao Xia² 

[1] School of Life Science, Anhui Agricultural University, Hefei 230036, Anhui, China;State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, Anhui, China;

关键词: Camellia sinensis;    flavanone-3-hydroxylase;    gene function;    flavonoids;   

DOI  :  10.3390/genes8110300

来源: DOAJ

【 摘 要 】

Flavonoids are major secondary metabolites in Camellia sinensis. Flavanone-3-hydroxylase (F3H) is a key enzyme in flavonoid biosynthesis in plants. However, its role in the flavonoid metabolism in C. sinensis has not been well studied. In this study, we cloned two F3Hs from C. sinensis, named CsF3Ha and CsF3Hb, where CsF3Ha containing 1107 bases encoded 368 amino acids, and CsF3Hb containing 1071 bases encoded 357 amino acids. Enzymatic activity analysis showed both recombinant CsF3H enzymes in Escherichia coli could convert naringenin and eriodictyol into dihydrokaempferol (DHK) and dihydroquercetin (DHQ), respectively. The expression profiles showed that CsF3Ha and CsF3Hb were highly expressed in the tender leaves of tea plants. Under different abiotic stresses, the two CsF3Hs were induced remarkably by ultraviolet (UV) radiation, sucrose, and abscisic acid (ABA). In the seeds of CsF3Hs transgenic Arabidopsis thaliana, the concentration of most flavonol glycosides and oligomeric proanthocyanidins increased significantly, while the content of monocatechin derivatives decreased. The present study revealed that CsF3Hs played critical roles in flavonoid biosynthesis in tea plants.

【 授权许可】

Unknown