水稻穗发芽调控基因OsVP1的RNA干涉载体构建及遗传转化研究  

Construction and Transformation of RNAi Vector of OsVP1 for a Regulatory Gene of Pre-Harvest Sprouting in Oryza sativa

作　　者：高永峰[1] 刘继恺[1] 范晶[1] 彭奕[1] 黄科[1] 张敦房[1] 刘永胜[1] 

机构地区：[1]四川大学生命科学学院/生物资源与生态环境教育部重点实验室,成都610064

出　　处：《中国农业科学》2010年第7期1321-1327,共7页Scientia Agricultura Sinica

基　　金：国家杰出青年科学基金(30825030);转基因生物新品种培育科技重大专项课题(2009ZX0809-072B)

摘　　要：【目的】穗发芽是种子在收获前遇到阴雨潮湿环境时,在田间母体植株上发芽的现象,是水稻生产中的一个重要限制因素。水稻穗发芽的表现性状和玉米种子特异的viviparous1(vp1)突变体表型非常相似。VP1是种子成熟和休眠所必须的脱落酸信号转导途径中的重要转录因子,因此利用转基因技术研究水稻同源基因OsVP1的生物学功能对有效控制杂交水稻穗发芽的发生和危害具有重要意义。【方法】将水稻OsVP1片段导入到植物表达载体pHB,构建OsVP1的RNA干涉植物表达载体pHB-OsVP1RNAi;通过根癌农杆菌介导转入水稻品种日本晴,并获得阳性植株。【结果】半定量RT-PCR分析显示,转基因植株胚中的OsVP1表达量明显低于野生型日本晴植株;萌发试验表明,转基因植株T1种子的萌发速率与野生型日本晴相比有明显的提高。并且在外加不同浓度的脱落酸(ABA)处理的溶液中,与野生型日本晴相比转基因种子萌发速率所受到的抑制较小;同时,在转基因植株T2新收获的稻穗的萌发试验表明,转基因的稻穗出现了明显的穗发芽现象。【结论】水稻OsVP1的RNA干涉能够提高种子的萌发速率以及诱发稻穗的穗发芽。[Objective] Pre-harvest sprouting is a phenomenon that seeds germinate while still attached onto the maternal plants in the condition of cloudy and rainy weather, and is also a restrictive factor of hybrid rice production and seed propagation. The phenotype of rice pre-harvest sprouting is very similar to that of maize seed-specific vpl mutant. VP1 gene is essential for seeds maturation and dormancy, and is also a key transcription factor of ABA signal transduction pathway. Thus, it is of great significance to effectively control the occurrence and hazard of hybrid rice pre-harvest sprouting. The aim of the current investigation is to dissect the biological function of homologous gene OsVP1 in Oryza sativa by using transgenic technology. [Method] To further elucidate the function of VP1, the RNA interference （RNAi） vector containing the sequence fragment of OsVP1 was constructed and introduced into rice cv. Nipponbare by Agrobacterium-mediated genetic transformation. [ Results ] Analysis of semi-quantitative RT-PCR revealed a distinct reduction of endogenous OsVP1 expression levels in RNAi transgenic lines compared with wild-type plants. Germination experiment showed that the percentage of geminated seeds from T1 transgenic plants was higher than that of wild-type plants. Under the different concentrations of abscisic acid （ABA） treatment, the inhibition of germination ratio of transgenic seeds was not significantly different when comparing with wild-type plants. Germination experiment of T2 panicles from transgenic plants showed more severe pre-harvest sprouting than wild-type plants. [ Conclusion ] RNA interference of OsVP1 gene can increase germination velocity of transgenic seeds and also lead to pre-harvest sprouting.

关 键 词：OsVP1 RNA干涉 农杆菌 水稻 

分 类 号：S511[农业科学—作物学]