Overexpression of a Bacterial Chitinase Gene in Plants: A Novel Approach to Disease Tolerance

在第一阶段研究中，从大肠杆菌中提取几丁质酶（chiA）基因， 粘质沙雷氏菌融合了三种不同的 已分离的启动子片段。 这些嵌合体 基因已经被引入烟草原生质体。 稳定 已经产生了转化的植物， 已被鉴定为表达高水平的chiA基因， mRNA和蛋白质水平。 这些已经被分析过了， 易受链格孢菌感染。 它 似乎他们表现出增加的抵抗力， 疾病 在第二阶段的研究中，计划改善 表达水平和特异性表达几丁质酶 组织（根）和细胞外。 以后基因会 转移到其他植物和它们对其他植物的抗性 将检测病原体。 这项实验研究将在烟草中进行 番茄和甘蓝型油菜，并将测定赋予 对链格孢属、白粉病和根的抗性 球形线虫 通过遗传控制广泛的真菌 植物工程可以大大提高作物产量 并防止化学杀真菌剂的过度使用。

In Phase I research the chitinase (chiA) gene from the bacterium Serrata marcescens has been fused to three different promotor fragments which have been isolated. These chimaric genes have been introduced into tobacco protoplasts. Stably transformed plants have been generated and individuals have been identified which express high levels of the chiA gene at both the mRNA and protein level. These have been assayed for susceptibility to infection by the fungus Alternaria. It appears that they exhibit an increased resistance to the disease. In this Phase II research, it is planned to improve the level of expression and to express chitinase in specific tissues (roots) and outside the cell. Later the gene will be transferred to other plants and their resistance to other pathogens will be tested. This experimental research will be performed in tobacco tomato and Brassica napus and will assay for conferred resistance against Alternaria, the powdery mildews, and root knob nematodes. Control of a broad range of fungi by genetic engineering of plants could greatly increase crop production and preclude the excessive use of chemical fungicides.