Cry1Ac敏感和抗性小菜蛾bre-3和bre-5基因mRNA的表达差异研究  

Research in expression differences of bre-3 and bre-5 mRNA in Plutella xylostella susceptible and resistant to Cry1Ac

作　　者：李拓[1,2] 张友军[2] 王少丽[2] 吴青君[2] 徐宝云[2] 杨中侠[2] 王沫[1] 

机构地区：[1]华中农业大学湖北省昆虫资源利用与害虫可持续治理重点实验室,武汉430070 [2]中国农业科学院蔬菜花卉研究所,北京100081

出　　处：《农药学学报》2011年第1期13-20,共8页Chinese Journal of Pesticide Science

基　　金：国家高技术研究发展计划(863计划)项目(2007AA10Z421);国家自然科学基金项目(30871659)

摘　　要：在室内选用Cry1Ac对小菜蛾Plutella xylostella 3龄幼虫进行抗性选育,获得相对抗性为356倍的抗性种群DBM1Ac-R品系。应用实时定量基因扩增荧光检测(real time quantitative PCR,real-time qPCR)技术检测敏感小菜蛾DBM1Ac-S和抗性小菜蛾DBM1Ac-R品系鞘糖脂(Glycosphingolipids,GSLs)合成酶基因bre-3和bre-5 mRNA在2龄、3龄、4龄和老熟幼虫、蛹及4龄中肠的表达情况。结果显示:bre-3和bre-5在两个品系的5个时期和4龄中肠均有表达,其中DBM1Ac-S品系的bre-3 mRNA在3龄、4龄和老熟幼虫的相对表达量显著高于DBM1Ac-R品系(P<0.05),分别为DBM1Ac-R品系的2.36、5.54和2.68倍;DBM1Ac-S品系的bre-5 mRNA在2龄至蛹期的相对表达量分别为DBM1Ac-R品系的1.19、3.13、1.78、1.75和1.65倍,其中由3龄到蛹期差异显著(P<0.05)。DBM1Ac-R品系3龄至老熟幼虫的bre-3和bre-5 mRNA相对表达量降低可能与小菜蛾长期的Cry1Ac汰选有一定的关系。比较同一种群、同一龄期(包括4龄中肠)的bre-3和bre-5 mRNA相对表达量差异时,发现bre-5相对表达量均高于bre-3。研究结果为苏云金芽孢杆菌(Bacillus thuringiensis,Bt)杀虫晶体蛋白受体之一GSLs的进一步研究提供了一定的基础。DBM1Ac-R strain of Plutella xylostella was selected with Cry1Ac in laboratory and showed 356-fold resistance to Cry1Ac compared with a susceptible strain（DBM1Ac-S）.The relative expression of synthetase gene of Glycosphingolipid（GSLs） bre-3 and bre-5 mRNA of DBM1Ac-S and DBM1Ac-R strains were determined using real-time qPCR,from 2nd-instar to mature larvae,pupa and midgut of 4th-instar.The results showed that both bre-3 and bre-5 mRNA were found to express in different development stages and midgut;The relative expression of bre-3 mRNA in DBM1Ac-S strain was significant higher than DBM1Ac-R strain,exhibiting 2.36,5.54 and 2.68 times in 3th-instar,4th-instar and mature larvae respectively;The relative expression of bre-5 mRNA in DBM1Ac-S strain were 1.19,3.13,1.78,1.75 and 1.65 times respectively compared with DBM1Ac-R strain from 2th-instar to mature larvae.The results suggested that there may be a correlation between the lower relative expression of bre-3 and bre-5 mRNA in DBM1Ac-R from 3th to mature larvae and the long-term Cry1Ac toxin selection to DBM1Ac-R strain.In the same stage of DBM1Ac-S and DBM1Ac-R strains,the mRNA level expression of bre-5 was higher than bre-3,showing obvious advantage of gene expression.These findings will provide important basis for further study on GSLs,one of the receptors of Bacillus thuringiensis crystal proteins.

关 键 词：鞘糖脂 苏云金芽孢杆菌 受体 bre-3 bre-5 

分 类 号：S481.4[农业科学—农药学] Q78[农业科学—植物保护]