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期 刊 ：植物研究 2015年 35卷 3期 页码：347-354

关键词：油茶；FAD2基因；载体构建；功能分析；

Keywords:Camelliaoleifera, FAD2gene, vectorconstrution, functionanalysis,

摘 要 ：茶油是从油茶种子中提取的食用植物油，富含油酸、亚油酸以及亚麻酸等多种人体必需的不饱和脂肪酸。在植物的不饱和脂肪酸生物合成途径中，脂肪酸脱饱和酶(Fatty Acid Desaturase，FAD)有多个家族成员，可以将单不饱和脂肪酸转化成多不饱和脂肪酸，其中FAD2可以将油酸(18∶1Δ⁹)和棕榈油酸(16∶1Δ⁹)转化成亚麻酸(18∶2Δ^9,11)和十六碳二烯酸(16∶2Δ^9,11)。为了揭示油茶FAD2基因的功能，本研究在原有的基础上构建了这个基因的植物表达载体pBI121-CoFAD2以及RNA干扰载体pBI121-CoFAD2 RNAi，并分别对相应的拟南芥突变体和野生型植株进行了转基因研究。结果表明，同野生型相比，fad突变体中，18∶1和16∶1含量较高，18∶2和16∶2含量较低；突变体植株经过植物表达载体的转化后，脂肪酸组分得到了恢复；而野生型植株经过RNA干扰载体的转化后，18∶1和16∶1含量升高，18∶2和16∶2含量降低。由此说明，油茶FAD2基因在植物体内具有调控18∶1和16∶1转变成18∶2和16∶2的功能，对于茶油脂肪酸组分的构成起着关键的调控作用。

Abstract:As an edible vegetable oil extracted from the seeds of Camellia oleifera, tea oil is rich in oleic acid, linoleic acid, linolenic acid and other unsaturated fatty acidwhich is essentialfor human beings healthy. In the plant biosynthesis pathway of unsaturated fatty acids, monounsaturated fatty acids are catalyzed into poly unsaturated fatty acids step by step by fatty acid desaturase(FAD) family members and FAD2 is mainly in chargeof catalyzing oleic acid(18∶1Δ⁹) and palmitoleic acid(16∶1Δ⁹) into linoleic acid(18∶2Δ^9,11) and hexadecadienoic acid(16∶2Δ^9,11). In order to reveal the function of CoFAD2 gene from C.oleifera, the plant expression vector pBI121-CoFAD2 and RNA interference vector pBI121-CoFAD2 RNAi were constructed on basis of the former research, and pBI121-CoFAD2 and pBI121-CoFAD2 RNAi were transferred into FAD2 mutant and wild type of Arabidopsis plants, respectively. Compared with the wild type, the content of oleic acid(18∶1) and palmitoleic acid(16∶1) was higher, the content oflinoleic acid(18∶2) and hexadecadienoic acid(16∶2) was lower in the FAD2 mutant; moreover,the fatty acid component of the mutant was recovered equal to wild type after transformation by pBI121-CoFAD2.However, the fatty acid component of the wild type plant was changed after transformation by pBI121-CoFAD2 RNAi, oleic acid(18∶1) and palmitoleic acid(16∶1) content increased and the content of linoleic acid(18∶2) and hexadecadienoic acid(16∶2) decreased.Therefore, CoFAD2 gene has function incontrol of catalyzing oleic acid(18∶1Δ⁹) and palmitoleic acid(16∶1Δ⁹) into linoleic acid(18∶2Δ^9,11) and hexadecadienoic acid(16∶2Δ^9,11) and plays an important role in the regulation of tea oil fatty acid composition.

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