疯草内生真菌中苦马豆素合成调控基因的筛选与功能研究

项目名称： 疯草内生真菌中苦马豆素合成调控基因的筛选与功能研究

项目编号： No.31201962

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 畜牧学与草地科学、兽医学、水产学

项目作者： 余永涛

作者单位： 宁夏大学

项目金额： 23万元

中文摘要： 疯草是严重危害草原畜牧业的毒草之一，其主要毒性成分为苦马豆素（Swainsonine, SW）。疯草内普遍存在能产生SW的内生真菌（Undifilim oxytropis），该真菌与疯草的毒性紧密相关，是疯草内SW产生的主要因素。抑制或阻断内生真菌合成SW可降低或消除疯草的毒性。本项目拟应用抑制差减杂交技术研究正常状态和诱导因子作用下内生真菌基因表达情况，构建抑制差减cDNA文库，筛选并克隆差异表达基因；根据差异表达基因构建RNA干扰载体，应用RNA干扰技术抑制或阻断内生真菌合成SW，从差异表达基因中筛选出与内生真菌合成SW相关的调控基因，分析并确定其功能，从分子水平探讨疯草内生真菌合成SW的调控机制。研究结果将为进一步阐释疯草内生真菌合成SW的机理奠定基础，为最终敲除内生真菌中SW合成调控基因，阻断SW生成，从控制内生真菌途径防除动物疯草中毒病提供依据。

中文关键词： 疯草；内生真菌；苦马豆素；合成；基因调控

英文摘要： Locoweeds are poisonous plants containing the toxic alkaloid swainsonine that causes significant economic losses to the livestock industry on western grasslands.The swainsonine-producing fungal endophytes, Undifilim oxytropis, are isolated frequently from locoweeds. There is a strong relationship between the presence of endophytes and swainsonine concentration of their host plants. The endophytes are believed to be responsible mainly for the toxicity of locoweeds. The toxicity of locoweed is likely to be reduced and eliminated by controlling the U. oxytropis within the locoweeds not to produce swainsonine. In this project, the gene expressions of endophytes treated in control and experimental conditions will be assessed by suppression subtractive hybridization(SSH). The SSH cDNA library will be constructed and differential expression genes will be isolated and cloned. The RNA interference(RNAi) vectors are also going to be developed to inhibit or interrupt the biosynthesis of swainsonine in the fungal cells according to the structures of differential expression genes. Some regulatory genes that related to the biosynthesis of swainsonine will be isolated from the differential expression genes and theirs functions will be knew. The controlling mechanism related to the biosynthesis of swainsonine will be tried to

英文关键词： locoweed；fungal endophyte；swainsonine；biosynthesis；gene regulation