【作者】 王红梅；

【导师】 沈金雄；

【作者基本信息】 华中农业大学 ， 作物遗传育种， 2014， 硕士

【摘要】 植物油脂的储存形式为三酰甘油(TAG),它是一种人类生活所必需的重要营养物质,也是重要的工业原料和潜在的可再生生物质能源。提高油料作物油脂含量是育种工作者改良作物品质性状的主要目标。而应用分子生物学方法分离油脂合成相关基因、研究植物油脂合成的分子机制显然已成为分子育种的重要方向。单酰甘油酰基转移酶MGAT是花生油脂合成过程中重要的调控因子,MGAT基因在酵母中的过表达可以导致甘油三酯的积累增加。在本研究中我们分别对拟南芥和油菜里MGAT的同源基因LYSOPL2和BnCC5进行了克隆和功能验证分析。本研究结果对于通过基因技术进一步提高油料作物含油量具有潜在应用价值。主要结果如下：1)分别在拟南芥和油菜里克隆了MGAT的同源基因LYSOPL2和BnCC5。2)构建了拟南芥LYSOPL2基因的过表达载体并转化拟南芥,构建了油菜BnCC5基因的RNAi干涉载体、含双35S和自身启动子的过表达载体。3)通过在拟南芥中过表达LYSOPL2基因,发现T3、T4和T5代转基因后代成熟种子的含油量与野生型相比较提高约2.6%,差异达到显著水平；T3代纯合的T-DNA插入突变体与野生型相比较,种子含油量降低4.51%,差异达到极显著水平,T4、T5代纯和的T-DNA插入突变体与野生型相比较,种子含油量降低0.6%,差异不显著。4)利用农杆菌介导转化法将油菜BnCC5基因的RNAi干涉载体、含双35S启动子的过表达载体成功转化到甘蓝型油菜Westar和甲572,获得了转化株。更多还原

【Abstract】 Plant oil is stored as triacylglycerol (TAG), it is a major source of essential polyunsaturated fatty acids for human. Besides, it is an important industrial materials and potential renewal biomass as well. Therefore, improving oil contents of oil crops is the main object for breeders. Nowadays, molecular breeding is one of the most important approaches to improve oil content. And a better understanding of oil regulation mechanism and its biosynthesis in developing seeds is highly necessary. As an important regulated factor in peanut, over-expression of MGAT (Monoacylglycerol acyltransferase) gene in yeast caused an increase in triacylglycerol accumulation. In this research, we cloned its homolog genes LYSOPL2in Arabidopsis and BnCC5in Brassica napus. Then, we analyzed their expressions and functions. Our findings can contribute to increasing oil content and modifying fatty acid composition in oil crops through genetic engineering. The main results are as follows:1. Using homologous gene cloning method, we cloned LYSOPL2in Arabidopsis and BnCC5in Brassica napus.2. Constructed over-expression vector of LYSOPL2and transformed it into Arabidopsis, Constructed RNAi and two over-expression (with double35S promoter and with its own promoter) vectors of BnCC5in Brassica napus.3. Compared the oil content among transgenic lines, T-DNA insertion mutants and wild-type in T3, T4and T5generations through over-expression of LYSOPL2in Arabidopsis. Hence, we found that oil content in transgenic lines was significantly increased (approximately2.6%) compared with wild-type in all the three generations. Besides, there was significant decrease (4.51%) in mutants when compared with the wild type in T3generation. However, mutants in T4and T5generations had no significant difference in oil contents with only0.6%decrease.4. Transformed BnCC5over-expression and RNAi vectors into Brassica napus Westar and J572and obtained transformed plants.更多还原