DHAR与草莓AsA积累关系及DHAR RNAi遗传转化研究

Relationship between DHAR and AsA accumulation in strawberry and its DHAR RNAi genetic transformation

【目的】确定草莓脱氢抗坏血酸还原酶(DHAR)酶活性与抗坏血酸(ASA)的关系,研究DHAR对AsA积累的调控作用,为筛选高AsA草莓品种育种提供理论基础。【方法】于不同时期测定草莓果实AsA含量和DHAR酶活性并进行相关性分析,构建DHAR基因RNAi植物表达载体,通过农杆菌介导法,将RNAi植物表达载体导入草莓中。【结果】草莓果实成熟过程中AsA含量呈现上升趋势,生长后期含量增幅最大。随着草莓果实的成熟,DHAR酶活性逐渐增大,在生长后期酶活性最高。构建了脱氢抗坏血酸酶基因(DHAR)的RNAi植物表达载体(Part27-IDHAR),并采用农杆菌介导法转入草莓,共获7株PCR阳性植株,初步说明目的基因已整合到草莓组织中。【结论】DHAR酶活性与AsA积累呈显著正相关,获得的转基因植株可为下一步研究提供植物材料。

[Objective]This research preliminarily identified strawberry DHAR enzyme activity and its relationship with AsA and studied the effects of DHAR on regulating AsA accumulation using RNAi technologies in order to provide theoretical basis for breeding high AsA strawberry varieties. [MethodlThe AsA and DHAR activities of strawberry fruit during different periods were measured and correlatively analyzed. By the Agrobacterium tumefaciens transformation medi- ated method, the RNAi plant expression vector of DHAR gene were constructed and introduced into strawberry. [Resultl The AsA content of strawberry fruit during ripening stage displayed an increasing trend, in which during the late growth period, the AsA content showed the largest increase. As the strawberry fruits matured, the DHAR activities increased gradually and measured the highest during the late growth stage. The plant expression vector RNAi （Part27-IDHAR） of the DHAR gene was constructed, and the Agrobacterium tumefaeiens transformation mediated method was used to trnasfer the gene into strawberry tissues. As a result, a total of 7 PCR-positive plants were obtained, and a preliminary description of the target gene was integrated into the strawberry tissues. [ Conclusion ] DHAR activity was significantly positive correlated to AsA accumulation. The obtained transformation plants could be as material for further study.