芸薹属蔬菜中的2-羟基-3-丁烯基硫苷（PRO）对动物有致甲状腺肿的潜在威胁，且是其苦味的主要来源，严重影响了芸薹属蔬菜的营养品质和商品价值。拟南芥中PRO由2-含氧依赖性双加氧酶（ODD）催化3-丁烯基硫苷（NAP）羟基化形成，但目前还未见芸薹属ODD的功能分析。课题组研究发现不同芥蓝基因型NAP向PRO转化效率（PRO/NAP）相差数十倍，为研究PRO的合成提供了代表性的材料。本研究将以芥蓝基因型省种（高PRO/NAP）和桃山中花（低PRO/NAP）为材料，克隆和分析芥蓝BaODD基因及其启动子，并从转录和翻译水平研究BaODD的表达模式与PRO转化效率的关系。构建该基因表达载体和RNAi干涉载体分别转化桃山中花和省种，验证BaODD在2-羟基-3-丁烯基硫苷合成中的功能。从分子水平解释NAP向PRO转化效率差异的原因，为通过基因工程创制低PRO含量的芸薹属材料提供理论基础。

The 2-hydroxybut-3-enyl glucosinolate (Progoitrin, PRO) synthesized in Brassica crops has biological activities including induction of goiter disease in mammals and production of bitter flavors in Brassica vegetable crops. This is a major impediment for the use of Brassica crops as it reduces their nutritional quality and potential value. The formation of PRO from its precursor, 3-butenyl glucosinolate (Gluconapin, NAP), requires 2-oxoacid-dependent dioxygenase (ODD) in Arabidopsis. To date, there is no study on function analysis of the ODD gene in the Brassica crops. Our previous results suggest there are big differences in the conversion efficiency of PRO from NAP (PRO/NAP) among different genotypes of Chinese kale. This provides a basis for the further study of the molecular mechanism of the synthesis of PRO. In this study, cloning the BaODD gene and its promoter will be conducted in genotypes of Taoshanzhonghua (PRO/NAP:0.04) and Shengzhong (PRO/NAP:2.31) of Chinese kale. The relationship between PRO/NAP and its expression patterns of mRNA as well as protein level will be investigated. Overexpression and RNAi of BaODD will be performed on genotypes of Taoshanzhonghua and Shengzhong respectively to study the function of BaODD as involved in the biosynthesis of 2-Hydroxybut-3-enyl Glucosinolate. The present study will help explain the molecular mechanism for the difference in PRO/NAP among different genotypes of Chinese kale, which will provide a basis for the generation of low-PRO Brassica crops by genetic engineering and breeding.