The NAC-like transcription factor CsNAC7 positively regulates the caffeine biosynthesis-related gene yhNMT1 in Camellia sinensis
The NAC-like transcription factor CsNAC7 positively regulates the caffeine biosynthesis-related gene yhNMT1 in Camellia sinensis
复制标题
NAC样转录因子CsNAC7正向调控茶树咖啡因生物合成相关基因yhNMT1
DOI：
10.1093/hr/uhab046
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发表时间：
2022-01-05
影响因子：
8.7
通讯作者：
Chen, Zhongzheng
中科院分区：
文献类型：
--
作者：
Ma, Wenhui;Kang, Xin;Chen, Zhongzheng
咖啡因是一种重要的功能物质，在茶树中含量丰富，但其生物合成如何受转录因子调控却知之甚少。本研究利用酵母单杂交实验从英红9号cDNA文库中分离出参与咖啡因合成的NAC样转录因子编码基因CsNAC7。该基因包含 1371 bp 核苷酸，预计编码 456 个氨基酸。 CsNAC7在茶树芽中转录水平的表达与春季和夏季的咖啡因合酶基因yhNMT1相似，其表达蛋白定位于细胞核。基因活性检测表明，CsNAC7在酵母中具有自激活活性，活性区域位于N末端，CsNAC7的瞬时表达能够显着促进yhNMT1在烟叶中的表达。此外，CsNAC7的过表达或沉默分别显着增加或减少了转基因茶愈伤组织中yhNMT1的表达和咖啡因的积累。我们的数据表明，分离的转录因子 CsNAC7 正向调节咖啡因合酶基因 yhNMT1 并促进茶树中咖啡因的积累。
Caffeine is an important functional substance and is abundant in tea plant, but little is known about how its biosynthesis is regulated by transcription factors. In this study, the NAC-like transcription factor-encoding gene CsNAC7, which is involved in caffeine synthesis, was isolated from a Yinghong 9 cDNA library using a yeast one-hybrid assay; this gene comprises 1371 bp nucleotides and is predicted to encode 456 amino acids. The expression of CsNAC7 at the transcriptional level in tea shoots shared a similar pattern with that of the caffeine synthase gene yhNMT1 in the spring and summer, and its expressed protein was localized in the nucleus. Assays of gene activity showed that CsNAC7 has self-activation activity in yeast, that the active region is at the N-terminus, and that the transient expression of CsNAC7 could significantly promote the expression of yhNMT1 in tobacco leaves. In addition, overexpression or silencing of CsNAC7 significantly increased or decreased the expression of yhNMT1 and the accumulation of caffeine in transgenic tea calli, respectively. Our data suggest that the isolated transcription factor CsNAC7 positively regulates the caffeine synthase gene yhNMT1 and promotes caffeine accumulation in tea plant.