Relationship between gene expression and the accumulation of catechin during spring and autumn in tea plants (Camellia sinensis L.).
The tea plant (Camellia sinensis L.) is an important commercial crop with remarkably high catechin concentrations. Tea is popular worldwide given the plant's health benefits. Catechins are the main astringent substance in tea and are synthesized mainly via the phenylpropanoid pathway. In this study, eight cultivars of tea plants harvested both in spring and autumn were used to investigate differences in catechin concentrations by using high-performance liquid chromatography. The expression levels of genes associated with catechin biosynthesis were investigated using reverse transcription-quantitative polymerase chain reaction. The results indicated that the total catechin (TC) concentrations were significantly higher in tea plants harvested in autumn than in those harvested in spring, based on higher concentrations of epigallocatechin (EGC) in autumn tea (P<0.01). The expression of the genes phenylalanine ammonia-lyase (PAL), flavanone 3-hydroxylase (F3H), flavonoid 3',5'-hydroxylase (F3'5'H), dihydroflavonol 4-reductase (DFR), and anthocyanidin synthase (ANS) is closely related to the TC content of tea plants in both spring and autumn. Positive correlations between PAL, cinnamate 4-hydroxylase (C4H), F3H, and DFR expression and EGC accumulation in autumn tea were identified, with correlation coefficients of 0.710, 0.763, 0.884, and 0.707, respectively. A negative correlation between ANS expression level and EGC concentrations in tea plants harvested in spring was noted (r=-0.732). Additionally, negative correlations between F3H and ANS expression levels and the catechin content were identified in spring tea, whereas the correlations were positive in autumn tea. Significant differences in the F3H and ANS expression levels between spring and autumn tea indicate that F3H and ANS are potentially key genes affecting catechin accumulation in tea plants.
School of Horticulture and Plant Protection, Yangzhou University , 48 Wenhui East Road, Yangzhou, Jiangsu 225009, P. R. China.
Min
M
Liu
School of Horticulture and Plant Protection, Yangzhou University , 48 Wenhui East Road, Yangzhou, Jiangsu 225009, P. R. China.
Heng-Lu
HL
Tian
Vocational and Technical College of Agriculture and Forestry (School of Agriculture) , 18 Wenchang East Road, Jurong, Jiangsu 212400, P. R. China.
Jian-Hua
JH
Wu
Tea Research Institute , Jurong, Jiangsu 212400, P. R. China.
Ren-Rong
RR
Cang
Tea Research Institute , Jurong, Jiangsu 212400, P. R. China.
Run-Xian
RX
Wang
School of Horticulture and Plant Protection, Yangzhou University , 48 Wenhui East Road, Yangzhou, Jiangsu 225009, P. R. China.
Xiao-Hua
XH
Qi
School of Horticulture and Plant Protection, Yangzhou University , 48 Wenhui East Road, Yangzhou, Jiangsu 225009, P. R. China.
Qiang
Q
Xu
School of Horticulture and Plant Protection, Yangzhou University , 48 Wenhui East Road, Yangzhou, Jiangsu 225009, P. R. China.
Xue-Hao
XH
Chen