杨树抗性基因在拟南芥中的转化及应用

发布时间：2018-02-16 13:22

本文关键词： 损伤诱导基因转基因拟南芥棉铃虫抗虫性胡杨大片段DNA 突变体库　出处：《天津大学》2013年硕士论文　论文类型：学位论文

【摘要】：棉铃虫（Helicoverpa armigera）是世界性重要农业害虫，它危害范围广、繁殖潜力大，对环境适应能力强。长期以来棉铃虫的防治主要是依赖化学农药，由于化学农药不合理的使用，使棉铃虫的抗性剧增，防治效果极不理想。同时，，大量的化学合成农药的使用，也向环境释放了大量的化学合成物质，直接或间接地对环境、生物和人类的健康构成了极大的威胁，也成为经济及社会发展的重大障碍因素之一。因此，进行生物防治是非常必要的。在本研究中，将三个杂交杨（Populus trichocarpa×美洲黑杨）基因PtdKTI5， PtdWIN4，PtdPOP3和1个白杨（Populus tremuloides Michx）基因PtKTI2分别转入拟南芥（Arabidopsisthaliana）进行过量表达。通过RT-PCR分析，证实了每个转基因拟南芥品系在转录水平上的高表达。用这四种转基因拟南芥喂养棉铃虫，并评估了其发育情况，体重变化以及存活率。结果表明：这四个杨树防御相关基因对棉铃虫幼虫和化蛹阶段表现出不同程度的抗虫作用，可用于植物基因工程来进行作物改良。林木抗逆、材性、生长发育等重要性状多是由多基因、多条信号途径交叉控制的复杂性状。林木基因工程研究虽然取得了一定进展，但目前克隆得到的单个基因在育种上的作用有限。植物经过长期进化，在染色体中形成了针对某性状的自然存在的基因簇。将外源基因簇导入植物基因组的同一位点，有可能赋予受体由多基因控制的新性状。大片段基因簇的同步插入还可以在一定程度上克服转基因带来的位置效应，减少基因沉默等不良现象。把多个以上协同作用的基因同时转入植物，将会获得比单基因转化更能获得理想的结果。胡杨是杨柳科杨属胡杨亚属的一种植物，常生长在沙漠中，它耐寒、耐旱、耐盐碱、抗风沙，并具有很强的生命力。本课题将以胡杨为材料，在前期获得的胡杨基因组大片段可转化细菌染色体库基础上，结合大片段DNA转化技术，获得拟南芥突变体库，进行基因功能验证，筛选出具有潜在育种价值的关键基因（簇）及调控元件，分离鉴定一批具有自主知识产权的优良性状相关基因（簇）及调控元件，为进一步通过分子育种方法培育高抗、优质林木新品种提供基础和保障。
[Abstract]:Helicoverpa armigera (Helicoverpa armigera) is an important agricultural pest in the world. At the same time, the use of a large number of chemical synthetic pesticides also released a large number of chemical synthetic substances to the environment, directly or indirectly to the environment, Biological and human health pose a great threat and become one of the major obstacles to economic and social development. Biological control is therefore essential. Three hybrid poplar genes PtdKTI5, PtdWIN4PtdPOP3 and one Populus tremuloides Michx were transferred into Arabidopsis thaliana (Arabidopsis thaliana) for overexpression. Confirmed the high expression at the transcriptional level of each transgenic Arabidopsis strain. The four transgenic Arabidopsis strains were fed to cotton bollworm and their development was evaluated. The results showed that the four poplar defense-related genes showed different degrees of resistance to cotton bollworm larvae and pupae stage and could be used in plant genetic engineering for crop improvement. Tree stress resistance, wood properties, growth and development are complex traits controlled by many genes and multiple signal pathways. Although some progress has been made in the study of tree genetic engineering, However, the single gene cloned at present has a limited role in breeding. After a long period of evolution, plants have formed naturally existing gene clusters in the chromosomes for a certain trait. The exogenous gene clusters are introduced into the same locus of the plant genome. It is possible to endow the receptor with new traits controlled by multiple genes. Simultaneous insertion of large gene clusters can also overcome the locational effects of transgenic genes to some extent. Reduce adverse phenomena such as gene silencing. Transferring more than one synergistic gene into a plant at the same time will yield a better result than a single gene transformation. Populus euphratica is a subgenus of Populus euphratica in the willow family, which often grows in the desert. It is hardy, drought-tolerant, saline-alkali resistant, wind-resistant, and has strong vitality. In this paper, Populus euphratica will be used as a material, on the basis of the genome large fragment transmutable bacterial chromosome bank obtained in the early stage, combined with the technology of large fragment DNA transformation. Arabidopsis mutants library was obtained, gene function was verified, key genes (clusters) and regulatory elements with potential breeding value were screened, and a number of genes (clusters) and regulatory elements with independent intellectual property rights were isolated and identified. It provides the foundation and guarantee for breeding new varieties of high resistance and high quality forest by molecular breeding method.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：Q943.2;S433

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