反义乙烯受体LeETR_2基因对番茄的转化和功能分析  

Transformation and Functional Analysis of Antisense Ethylene Receptor LeETR_2 Gene in Tomato

作　　者：张明方[1] 向庆宁[1] 应铁进[2] 杨虎清[2] 郑铁松[3] 杜荣茂[2] 

机构地区：[1]浙江大学农业与生物技术学院,杭州310029 [2]浙江大学农业工程与食品科学学院,杭州310029 [3]南京师范大学女子学院,南京210095

出　　处：《农业生物技术学报》2003年第2期144-147,共4页Journal of Agricultural Biotechnology

基　　金：国家自然科学基金资助项目(39870512)。

摘　　要：采用根癌农杆菌(Agrobacteriumtumefaciens)介导法将LeETR2的部分反义序列导入番茄(Lycopersiconesculentum)子叶外植体,经抗性筛选和组织培养获得再生植株。通过对转基因植株中插入序列的PCR检测和Southern杂交,证明转化番茄成功。通过对LeETR2的功能的初步研究结果表明,转基因植株顶端优势丧失、极端矮化和番茄果实的内源乙烯合成量增加。这提示此基因在植物乙烯信号感受与转导系统中起着负调控的作用。An antisense ethylene receptor gene LeETR2 was introduced into tomato (Lycopersicon esculentum ) through Agrobacberium tumefaciens -mediated method. Plantlets were regenerated in vitro by resistance selection on MS medium containing various concentrations of kanamycin. Approximately 73.5% of calli and 38.5% of leaves from plantlets exhibited intense blue color reaction by histochemical GUS assays. By PCR-aided assays, transformed plants displayed 362 bp (antisense LeEtr2 gene)and 500 bp(NPTⅡ) amplification products, however, they were not detected in non-transformed controls. Furthermore, Southern hybridization of DNA from PCR-positive transformants with the NPTⅡ probe indicated that the inserted gene was single copied in genome, by which it was further confirmed that the antisense LeETR2 gene was transferred into tomato. The transformants in tested lines showed delayed abscission, less elongated internodes(6±1.5) cm in length for transgenic plants and (8±1.58) cm for control, and out-growed axillary buds. The endogenous ethylene levels in fruits at day 3 after breaker in transgenic lines 1~5 were 155.58%, 166.96%, 251.76%, 441.07% and 100.89% of those in the controls, respectively. It is still ambiguous that how ethylene interacts with other hormones, such as auxin, abscisic acid and cytokinin in regulation of plant development through signal pathways. Nevertheless, the ethylene receptor LeETR2 might play a negative regulatory role in the signal transduction, and possibly involve other hormones in the control of plant development. It is essential to make clear how the antisense LeETR2 gene acts at transcriptional or translational level in the regulation of ethylene receptor LeETR2 gene, and whether it has regulatory side-effect on ethylene receptor LeETR1 gene due to their high sequence homologies.

关 键 词：番茄 乙烯受体 反义转化 LeFTR2基因 

分 类 号：S641.2[农业科学—蔬菜学]