Functional analysis of flavonoid 3',5'-hydroxylase from tea plant (Camellia sinensis): critical role in the accumulation of catechins.
Functional analysis of flavonoid 3',5'-hydroxylase from tea plant (Camellia sinensis): critical role in the accumulation of catechins.
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DOI：
10.1186/s12870-014-0347-7
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发表时间：
2014-12-10
影响因子：
5.3
通讯作者：
Xia T
中科院分区：
文献类型：
--
作者：
Wang YS;Xu YJ;Gao LP;Yu O;Wang XZ;He XJ;Jiang XL;Liu YJ;Xia T
黄酮3′，5 ′-羟化酶（F3′5′H）属于CYP 75 A亚家族，是茶树黄烷-3-醇合成过程中的一个重要分支点酶，催化黄酮、黄烷酮、二氢黄酮醇和黄酮醇类化合物转化为3′，4 ′，5 ′-羟基化衍生物。然而，B环羟基化是否发生在黄烷酮和/或二氢黄酮醇的水平，在体内仍然未知。从茶树cDNA文库中克隆了茶树F3′5′H（CsF 3 ′5′H）基因。表达谱分析表明，CsF 3 ′5′H在芽中的表达量很高，在根中的表达量很低，具有组织特异性。CsF 3 ′5′H的表达受光照和蔗糖的影响。过量表达CsF 3 ′5′H产生新的飞燕草素衍生物，增加了转基因烟草花冠中矢车菊素衍生物的含量，使转基因烟草的花色变深。为研究CsF 3 ′5′ H酶的体外功能，在酵母中进行了CsF 3 ′ 5 ′H的异源表达。对修饰后的CsF 3 ′5′H（CsF 3 ′5′H基因与葡萄属葡萄信号肽FSI融合）进行异源表达，结果表明，4′-羟基黄烷酮（naringenin，N）是CsF 3 ′5′H的最适底物，并能有效转化为3′4′-和3′4′5′-两种形式。FSI转基因细胞中3′4′5′-羟基化产物与3′4′-羟基化产物的比例显著高于VvF 3 ′5′H细胞。CsF 3 ′5′H是茶树中三羟基黄烷-3-醇合成的关键控制因子，能有效地将4′-羟基黄烷酮转化为3′4′5′-和/或3′4′-羟基黄烷酮。这些结果为进一步研究茶树黄酮类化合物的生物合成提供了重要依据。这些研究将有助于加速类黄酮代谢工程，以增加B环三羟基产物的产率。本文的在线版本（doi：10.1186/s12870-014-0347-7）包含补充材料，可供授权用户使用。
Flavonoid 3′,5′-hydroxylase (F3′5′H), an important branch point enzyme in tea plant flavan-3-ol synthesis, belongs to the CYP75A subfamily and catalyzes the conversion of flavones, flavanones, dihydroflavonols and flavonols into 3′,4′,5′-hydroxylated derivatives. However, whether B-ring hydroxylation occurs at the level of flavanones and/or dihydroflavonols, in vivo remains unknown. The Camellia sinensis F3′5′H (CsF3′5′H) gene was isolated from tea cDNA library. Expression pattern analysis revealed that CsF3′5′H expression was tissue specific, very high in the buds and extremely low in the roots. CsF3′5′H expression was enhanced by light and sucrose. Over-expression of CsF3′5′H produced new-delphinidin derivatives, and increased the cyanidin derivative content of corollas of transgenic tobacco plants, resulting in the deeper transgenic plant flower color. Heterologous expressions of CsF3′5′H in yeast were carried out to demonstrate the function of CsF3′5′H enzyme in vitro. Heterologous expression of the modified CsF3′5′H (CsF3′5′H gene fused with Vitis vinifera signal peptide, FSI) revealed that 4′-hydroxylated flavanone (naringenin, N) is the optimum substrate for CsF3′5′H, and was efficiently converted into both 3′4′- and 3′4′5′-forms. The ratio of 3′4′5′- to 3′4′-hydroxylated products in FSI transgenic cells was significantly higher than VvF3′5′H cells. CsF3′5′H is a key controller of tri-hydroxyl flavan-3-ol synthesis in tea plants, which can effectively convert 4′-hydroxylated flavanone into 3′4′5′- and/or 3′4′-hydroxylated products. These findings provide animportant basis for further studies of flavonoid biosynthesis in tea plants. Such studies would help accelerate flavonoid metabolic engineering in order to increase B-ring tri-hydroxyl product yields. The online version of this article (doi:10.1186/s12870-014-0347-7) contains supplementary material, which is available to authorized users.
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影响因子：
4.4
作者：
Falginella L;Castellarin SD;Testolin R;Gambetta GA;Morgante M;Di Gaspero G
通讯作者：
Di Gaspero G
影响因子：
11.4
作者：
Lei, Zhi-Yong;Zhao, Ping;Xiang, Cheng-Bin
通讯作者：
Xiang, Cheng-Bin
影响因子：
1.6
作者：
Okinaka, Y;Shimada, Y;Kikuchi, Y
通讯作者：
Kikuchi, Y
影响因子：
5.4
作者：
De Jong, WS;Eannetta, NT;Bodis, M
通讯作者：
Bodis, M
影响因子：
3.9
作者：
Punyasiri, PAN;Abeysinghe, ISB;Fischer, TC
通讯作者：
Fischer, TC