同步抑制FAD2与FatB基因提高烟草种子油酸组分含量的研究

该研究以烟草品系NC89的无菌苗叶片为受体材料,采用前期构建的能同步抑制种子中FAD2(Δ12-油酸去饱和酶基因)与FatB(酰基转移酶基因)表达的RNAi载体,通过农杆菌介导转化获得了转基因烟草植株,分析转基因植株种子中的脂肪酸组分。结果显示:与对照相比,转基因植株种子中FAD2和FatB基因的表达水平分别降低了23%和11%;转基因植株种子的脂肪酸组分中,饱和脂肪酸棕榈酸和硬脂酸平均含量分别为8.02%和4.45%,多不饱和脂肪酸亚油酸平均含量为76.82%,较对照分别降低了2.91%、9.92%和3.47%;而转基因植株种子中单不饱和脂肪酸油酸含量高达7.48%,比对照提高46.38%。研究表明,同步抑制FAD2和FatB基因的表达能够显著提高烟草种子中油酸组分的含量,为进一步改良油料作物品质奠定了基础。

Increasing Oleic Acid Content in Tobacco Seeds by Simultaneous Silencing FAD2 and FatB Genes

In this study,tobacco leaves (cultivar NC89) were transformed by the Agrobacterium-mediated with a dual-target FAD2 and FatB genes silencing RNAi vector,which was successfully constructed by our previous study.Further,transgenic plants were screened and fatty acids in seeds were analyzed.The results have shown that the expression levels of FAD2 and FatB in seeds of transgenic plants were decreased by 23% and 11% compared with the control group.The contents of saturated fatty acid,palmitic acid and stearic acid,reached to 8.02% and 4.45% in the fatty acid composition of transgenic seeds,respectively.The content of polyunsaturated linoleic fatty acid was 76.82%.Compared with the control group,the contents were reduced by 2.91%,9.92% and 3.47%,respectively.The content of monounsaturated fatty acid oleic acid in transgenic plants reached to 7.48%,which increased by 46.38% than the control.The results have shown that simultaneous inhibition of FAD2 and FatB expression levels in tobacco seeds significantly increased the content of oleic acid composition,which laid a foundation for the further improvement of oil crop quality.