State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing 100091, China; Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, Zhejiang Province, China.
State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing 100091, China; Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, Zhejiang Province, China.
Int J Biol Macromol. 2023 Mar 31;232:123378. doi: 10.1016/j.ijbiomac.2023.123378. Epub 2023 Jan 27.
Litsea cubeba, an aromatic species of the Lauraceae family, produces a diverse array of monoterpenes. The biosynthesis of monoterpenes is regulated by transcriptional factors (TFs), such as APETALA2/ethylene response factor (AP2/ERF). However, the regulatory mechanisms that control the AP2/ERF gene responsible for the biosynthesis of monoterpenes in L. cubeba have yet to be elucidated. Here, we identified an AP2/ERF gene, LcERF134, as an activator for the accumulation of citral and other monoterpenes. The expression level of LcERF134 was consistent with terpene synthase LcTPS42 in the pericarp. The transient overexpression of LcERF134 significantly increased monoterpene production in L. cubeba as well as the expression of rate-limiting genes involved in the monoterpene biosynthesis pathway. Furthermore, yeast one-hybrid, dual-luciferase and electrophoretic mobility shift assays demonstrated that LcERF134 activated the monoterpene biosynthesis pathway by directly binding to the GCC-box elements of the LcTPS42 and LcGPPS.SSU1 promoters. However, the overexpression of LcERF134 in tomatoes had no impact on the synthesis of monoterpenes, thus indicating that LcERF134 is a species-specific TF. Our research demonstrated that LcERF134 significantly increased the biosynthesis of monoterpenes by inducing the expression of LcTPS42 and LcGPPS.SSU1, thus offering insight into how to enhance the flavor of L. cubeba essential oil.
山鸡椒是樟科的一种芳香物种，可产生多种单萜烯。单萜烯的生物合成受转录因子（TFs）调控，如 APETALA2/ethylene response factor（AP2/ERF）。然而，控制山鸡椒单萜烯生物合成的 AP2/ERF 基因的调控机制尚不清楚。在这里，我们鉴定了一个 AP2/ERF 基因 LcERF134，它是柠檬醛和其他单萜烯积累的激活子。LcERF134 的表达水平与果皮中的单萜合酶 LcTPS42 一致。LcERF134 的瞬时过表达显著增加了山鸡椒中单萜的产生，以及参与单萜生物合成途径的限速基因的表达。此外，酵母单杂交、双荧光素酶和电泳迁移率变动分析表明，LcERF134 通过直接结合 LcTPS42 和 LcGPPS.SSU1 启动子的 GCC 盒元件，激活单萜生物合成途径。然而，LcERF134 在番茄中的过表达对单萜的合成没有影响，这表明 LcERF134 是一种种特异性 TF。我们的研究表明，LcERF134 通过诱导 LcTPS42 和 LcGPPS.SSU1 的表达，显著增加了单萜烯的生物合成，从而为如何增强山鸡椒精油的风味提供了思路。
