【摘要】 通过基因工程手段抑制甘蓝型油菜Δ12-油酸去饱和酶(delta-12 oleate desaturase FAD2)基因的表达,从而使油酸脱饱和产生亚油酸的步骤受阻,达到富集油酸,减少多不饱和脂肪酸含量的最终目的。依据植物RNA干扰的原理和研究中用于构建RNAi载体的基本经验,选择油菜fad2基因片段(510bp)分别以反向和正向的形式插入到油菜napin启动子下游,并在反向和正向插入的基因片段之间即间隔区导入1个来源于豌豆的rbcS-3C基因内含子(83bp)及其剪切位点之前5bp、之后4bp片段。组装完成的fad2RNAi载体转入到植物双元表达载体pCAMBIA3301,植物筛选标记基因采用抗灭生性除草剂PPT的选择基因bar及报告基因gus,从而构建成以甘蓝型油菜fad2基因为靶标的RNAi植物表达载体pCAMBIA3301-fad2i。更多还原

【Abstract】 This study was aimed to block linolic acid biosynthesis by RNAi strategy targeting delta-12 oleate desaturase gene(fad2)limiting multi-unsaturated fatty acid synthesis in rapeseed(Brassica napus).The gene-specific sequences of fad2 in the antisense and sense orientations interrupted by a spliceable intron from pea rbcS-3C gene,were cloned into a binary vector pCAMBIA3301.A seed-specific promoter previously isolated from B.napus napin gene was used to control the transcription of the trangene.The constructed structure was then inserted into plant vector pCAMBIA3301 and the recombinant plasmid pCAMBIA3301-fad2i was obtained,in which,bar gene is a selection marker and gus gene is a detection marker.更多还原