瞬时表达比较马铃薯X病毒CP基因3种结构对RNA沉默的诱导效果

RNA沉默是植物抵御病毒侵染的一种防卫机制,病原来源的抗性(pathogen-derived resistance,PDR)被认为是通过RNA沉默起作用的.转化的核酸片段在基因组中的位置、长短和不同排列结构等均影响RNA沉默的效率.用全长马铃薯X病毒(PVX)CP基因构建非翻译的正义、反义和反向重复结构转基因的植物表达载体,通过农杆菌渗入法瞬时表达测试了这些转基因对RNA介导抗性的诱导效率和有效性.结果表明,反向重复的PVXCP是更为有效的RNA沉默诱导因子,同时也证明让目的基因在受试植物中瞬时表达,在转化植物之前能比较快速地检测转基因的表达情况以及表达产物的功能,从而节约时间和资源,并减少盲目性.图3表2参21

Comparison of RNA Silencing Inducing Efficiency of Three PVX CP Gene Constructs via Transient Expression

In plant, RNA silencing is an adaptive defense mechanism against virus infection, and pathogen-derived resistanceis attribute to this mechanism. The size, arrangement and location of transgenes in transgenic plant genome affect the efficiency of RNA silencing inducing. Plant expression vectors with untranslatable transgene arranged as sense, antisense orientation and inverted repeat were constructed with the full-length potato virus X (PVX) coat protein (CP) gene and their efficiency of RNA silencing inducing was analyzed after transient expression via agroinfiltration. The results showed that the inverted repeat was the most efficient inducer. By agroinfiltration transient expression system, the expression and function of the transgene could be quickly tested, so as to save time and resources. Fig 3, Tab 2, Ref 21