桃果实内酯类香气物质的生物合成及其调控机制研究

项目名称： 桃果实内酯类香气物质的生物合成及其调控机制研究

项目编号： No.31260467

项目类型： 地区科学基金项目

立项/批准年度： 2013

项目学科： 农业科学

项目作者： 席万鹏

作者单位： 石河子大学

项目金额： 60万元

中文摘要： 桃是一种世界性水果，香味浓郁，深受消费者喜爱。内酯属"桃味"化合物，是桃果实最重要的特征香气物质，对成熟桃的香味具有决定性作用。申请人研究发现，脂肪酸β-氧化的起始酶ACX参与了桃内酯的合成，但其下游具体合成途径尚不清楚。故本项目拟在前期研究基础上，以'早露蟠桃'为材料，通过稳定同位素13C饲喂技术标记内酯的前体物质脂肪酸，建立从脂肪酸到内酯的线性标记体系，使用UPLC-MS/MS及核磁共振技术鉴定内酯合成的中间产物，利用Deep sequencing/qPCR技术，发掘参与内酯合成的关键基因，并使用酵母表达蛋白进行验证，在上述基础上，建立桃果实内酯合成的线性模型，明确其生物合成机制。通过分析采后温度对内酯合成关键步骤的影响，揭示冷害抑制内酯合成的原因，阐明间歇升温对桃果实内酯合成的调控机制。本项目研究结果将有助于明确桃果实内酯合成的具体途径，为桃品质育种和香气品质调控提供理论和实践依据。

中文关键词： 桃；内酯；转录组；基因；转录因子

英文摘要： Peach is a worldwide fruit species, and deeply loved by consumers because of its strong aromas. Lactone was considered as 'peach-like' compound and it is the most important characteristic aroma component for peach fruit.It play decisive role in aroma of ripen peach. My previous work showed that the first enzyme in the process of β-oxidation,acetyl coenzyme A(ACX), involved in lactone biosynthesis. However, it was not well known synthesis step, especially downstream ACX. On the base of our previous study，'zaolu' flat peach was used to study lactones biosynthesis and regulation mechanism of postharvest temperature.13C stable-isotope technique was used to mark fatty acid of the precursor of lactones. The mark system from fatty acid to lactone was established. Metabolic intermediate were indentified and molecular structure were characterized by using Ultra-Performance Liquid Chromatography tandem Mass Spectrometry (UPLC-MS/MS) and Nuclear Magnetic Resonance(NMR). Differentially expressed gene were identified by using deep sequencing and qPCR. And which was combined with metabolic intermediate to infer possible key gene involved in lactones biosynthesis. Based on verifying results by using yeast expression, the biosynthetic linear model was constructed, which make the mechanism of lactone biosynthesis clear. The ef

英文关键词： Peach；lactones；transcriptome；gene；transcriptional factor