【摘要】 通过农杆菌介导的遗传转化法将拟南芥八氢番茄红素合成酶基因(phytoene synthase,Atpsy)和按照拟南芥偏爱密码子人工合成的编码三磷酸腺苷环化水解酶(GTP cyclohydrolase,GCHI)的folE基因共同转入罗曼生菜中,通过Realtime-PCR、HPLC、干酪乳杆菌发酵法分别测定了转基因生菜中目标基因的表达量、叶黄素和β-胡萝卜素含量以及总叶酸含量。实验结果表明:转基因生菜中Atpsy基因表达量为野生型的43.54倍,folE基因表达量为野生型的38.05倍;转基因生菜植株叶黄素和β-胡萝卜素含量与野生型相比均有提高,含量最好的转基因植株L13中叶黄素含量为7.1mg/kg(鲜重,下同),是野生型对照6.8mg/kg的1.1倍,β-胡萝卜素含量为592.6mg/kg,是野生型对照196.9 mg/kg的3倍;叶酸含量最高是2 083.4 mg/kg,为野生型对照1 129.1mg/kg的1.85倍。该研究为通过基因工程手段改良类胡萝卜素和叶酸在植物体内的代谢途径,获得同时富含类胡萝卜素和叶酸的新型生菜品种打下了基础。更多还原

【Abstract】 Lactuca sativa L.was transformed with Agrobacterium strain containing Atpsy coding phytoene synthase from Arabidopsis thaliana and synthetic folE gene synthesized according to the coding-biased Arabidopsis sequence of GTP cyclohydrolase(GCHI) through Agrobacterium-mediated leaf-disc transformation.Realtime-PCR,HPLC and Lactobacillus casei fermentation were used respectively to measure the expression of the target genes in transgenic lettuce including lutein,β-carotene contents,and total folate content.The results showed that the expression levels of the introduced Atpsy and folE genes were increased by 43.54 folds and 38.05 folds,respectively,compared with that of control.Lutein and β-carotene contents in transgenic plants were higher than that in the control plants.Compared with wild type,the contents of lutein,β-carotene and folate was improved by 1.1,3.0 and 1.85 fold [7.1 mg/kg(FW,same as below) versus 6.8 mg/kg,592.6 mg/kg versus 196.9 mg/kg and 2 083.4 mg/kg versus 1 129.1 mg/kg] respectively in the transgenic plant L13 with the highest performance.This study provides a basis for developing new lettuce varieties rich in carotenoids and folate contents by manipulating carotenoids and folate metabolic pathways through genetic engineering.更多还原