Genomic Basis of Specificity in Glucosinolate Hydrolysis

芥子油苷水解特异性的基因组基础

• 批准号: 0323759
• 负责人: Daniel Kliebenstein
• 金额: $ 28.92万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2007-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0323759&HistoricalAwards=false
• 关键词: Genomic; Basis; Specificity; Glucosinolate; Hydrolysis

Plants produce a vast catalog of secondary metabolites, partly generated by diverse structural modifications of common backbone structures. Glucosinolates, low-molecular-weight, sulfur rich thioglucosides, are a prime example of how a single molecular backbone can be modified to produce an amazing array of secondary metabolites. A single species, Arabidopsis thaliana, can derive 30 different glucosinolates from the methionine glucosinolate backbone that can be amplified to over 100 different compounds during glucosinolate hydrolysis. The biological activity of a glucosinolate is fully realized after degradation by the protein, myrosinase. This produces a series of different compounds such as isothiocyanates, nitriles, and epithionitriles that differentially impact human health. In Arabidopsis, a relative of many brassica vegetables, numerous genetic loci determine the hydrolytic path of glucosinolates. One locus, ESM1, previously defined only in genetic terms, will be cloned and characterized at the molecular level. Further, the biochemical impact of ESM1 on glucosinolate hydrolysis will be investigated. Glucosinolate structural modifications serve to control diverse biological activities that help the plant defend itself from insects, nematodes, fungi as well as containing the potential to greatly benefit human nutrition when modified in common Brassica crops. A key point in controlling glucosinolate biological activity is at the hydrolysis step. This step controls the production of compounds with dramatic differences in biological activity. For example, a given glucosinolate's isothiocyanate exhibits stronger cancer prevention activities and anti-insect/fungal activities than do the corresponding nitriles. Characterizing the Arabidopsis glucosinolate hydrolytic system could impact fields ranging from ecology to evolution to human nutrition. Additionally, the ESM1 locus may be useful in producing crops with altered insect and pathogen resistance as well as altered nutritional value for human consumption. Further, involving undergraduates and postdoctoral researchers in this project will expose them to a broad range of techniques and help to train them for their own future research.

植物产生大量的次生代谢物，部分是由常见主链结构的不同结构修饰产生的。芥子油苷是一种低分子量、富含硫的硫代葡萄糖苷，是如何修饰单分子主链以产生一系列令人惊叹的次级代谢产物的典型例子。单一物种拟南芥可以从甲硫氨酸芥子油苷主链衍生出 30 种不同的芥子油苷，这些芥子油苷在水解过程中可以扩增为 100 多种不同的化合物。芥子油苷的生物活性在被蛋白质黑芥子酶降解后完全实现。这会产生一系列不同的化合物，如异硫氰酸酯、腈和环硫腈，对人类健康产生不同的影响。在拟南芥（许多芸苔属蔬菜的近亲）中，许多遗传位点决定芥子油苷的水解路径。一个基因座 ESM1 以前仅在遗传学术语中定义，现在将在分子水平上进行克隆和表征。此外，还将研究 ESM1 对芥子油苷水解的生化影响。 芥子油苷结构修饰有助于控制多种生物活性，帮助植物防御昆虫、线虫、真菌的侵害，并且在普通芸苔属作物中进行修饰后，具有极大有益于人类营养的潜力。控制芥子油苷生物活性的关键点是水解步骤。此步骤控制生物活性显着差异的化合物的产生。例如，给定的芥子油苷的异硫氰酸酯比相应的腈表现出更强的癌症预防活性和抗昆虫/真菌活性。拟南芥芥子油苷水解系统的表征可能会影响从生态学到进化到人类营养等各个领域。此外，ESM1基因座可用于生产具有改变的昆虫和病原体抗性以及改变的人类食用营养价值的作物。此外，让本科生和博士后研究人员参与该项目将使他们接触到广泛的技术，并有助于为他们自己未来的研究进行培训。