Molecular breeding of transgenic solanaceous plants showing the resistance to Ralstonia solanacearum by the introduction of lysozyme gene

青枯雷尔氏菌（Ralstonia solanacearum）是青枯菌属植物的主要致病菌。尽管人们采取了许多防治措施，但至今尚未建立起一种有效的保护植物的方法。本研究拟通过转溶菌酶基因烟草植株的培育，培育对青枯菌具有遗传抗性的烟草植株。此外，我们利用豌豆PSPAL 1启动子控制溶菌酶基因的表达，该启动子具有根特异性和病原菌可诱导的表达模式，我们认为以下结果包含了本研究的重要成果.从青枯雷尔氏菌噬菌体P4282中分离出溶菌酶蛋白及其相关基因，并对其结构进行了鉴定.我们构建了由表达极高启动子活性的PSPAL 1启动子的调控顺式元件（Box I、Box II和Box IV）组成的重复启动子。特别是重复启动子在根中的活性比CaMV 35S启动子高出6.5倍.将上述CaMV 35S启动子、PSPAL 1启动子或重复启动子分别与溶菌酶基因融合，转化烟草植株.整合了嵌合溶菌酶基因的转基因烟草表达了较高的溶菌酶活性.通过接种35S：：Lux基因表达盒，将转基因的R.在转PSPAL 1启动子：：GUS报告基因的烟草植株上进行青枯菌的表达，建立了同时研究寄主防御反应和病原菌行为的监测系统。

Ralstonia solanacearum is a causal agent of bacterial wilt mainly to solanacearum plants. Although many approaches were made to control this pathogen, a sure method to protect the plants was not established yet. In this study, to breed genetically resistant solanacearum plants to this pathogen, we planed to generate the transgenic tobacco plants expressing the lysozyme gene isolated from the bacteriophage of this bacterium. Furthermore we utilized pea PSPAL1 promoter which shows root spec and pathogen-inducible expression pattern for the control of lysozyme gene.We considered that the following results include the significant achievements in this research.1. From bacteriophage P4282 of Ralstonia solanacearum, we isolated lysozyme protein and correspond gene, and structurally characterized.2. We constructed the repeat promoter consisting the regulatory cis-elements (Box I, Box, II and Box IV of PSPAL1 promoter that expressed extremely high promoter activity. Especially the repeat promoter exhibited 6.5 hold activity than CaMV 35S promoter in roots.3. Each CaMV 35S promoter, PSPAL1 promoter or the repeat promoter described above was fused with lysozyme gene, and transformed tobacco plants.4. The transgenic tobacco plants that integrated chimeric lysozyme gene expressed higher lytic enzyme activity.5. By the inoculation of 35S :: Lux gene cassette introduced R. solanacearum on the transgenic tobacco plants possessing PSPAL1 promoter :: GUS reporter gene enabled to establish the monitoring system to investigate the host defense response and behavior of bacterial pathogen simultaneously.