金银花MYB类转录因子LjMYB12对绿原酸生物合成的调控研究

Honeysuckle (Lonicera japonica) is an important medicinal plant known for its multiple pharmacological properties such as anti-oxidative, anti-inflammatory, antiviral, anti-carcinogenic and so on. Chlorogenic acid is the most major ingredient for honeysuckle’s pharmacological activities and the content of which is used as the main indicators of quality for the evaluation of honeysuckle. As one of the most important secondary metabolites in plants, the biosynthesis of chlorogenic acid is catalyzed by a series of enzymes encoded by structural genes which strictly regulated by a variety of transcription factors. The study of chlorogenic acid biosynthesis related structural genes has made significant progress in plants, but little is known about the regulation genes. In our earlier study, we analyzed the MYB gene family in honeysuckle based on transcriptome sequencing data and identified a MYB gene named as LjMYB12, which showed high similarity with AtMYB12 of Arabidopsis. In this work, we intend to employed expression analysis, subcellular localization, ChIP, gene silencing and gene overexpression approaches to study the regulation function of LjMYB12 in chlorogenic acid biosynthesis. This study will provide insight into chlorogenic acid genetic improvement using transcription factor genetic engineering in honeysuckle.

金银花是一种重要的药用植物，具有抗氧化、抗炎、抗病毒、抗癌等多种药效。绿原酸是金银花中最为主要的药用活性成分，其含量是评价药用金银花质量的主要指标。作为一种重要的植物次生代谢产物，绿原酸的生物合成是由许多结构基因所编码的酶催化的一系列代谢反应所组成，而结构基因的表达受到众多转录因子的严格调控。目前植物中绿原酸结构基因的研究已取得很大进展，但是其转录调控研究却鲜有报道，而金银花中至今未见相关报道。本项目组前期基于金银花转录组数据分析了其MYB家族转录因子，鉴定并克隆了一个与拟南芥AtMYB12同源的MYB类转录因子编码基因，命名为LjMYB12。本研究拟通过表达分析、亚细胞定位、ChIP、基因沉默、基因过表达等方法研究LjMYB12对金银花绿原酸生物合成的调控机制。该研究对利用转录因子基因工程实现金银花绿原酸遗传改良具有重要指导意义。