Establishment of a Multiplex PCR System for Detecting Transgenic Ingredients from Citrus

柑橘转基因成分多重PCR检测体系的建立(英文)

[Objective] This study aimed to establish a multiplex PCR system for de- tecting transgenic ingredients from Citrus. [Method] Based on the pBI121 plasmid sequences published in GenBank and actin gene sequence of Citrus, the primers specific to CaMV35S promoter, NOS promoter, NOS terminator and actin gene were designed, to establish a multiple PCR system which could detect four types of sequences. In addition, orthogonal tests were performed to determine the optimal concentrations of all the components in PCR reaction system, as well as the optimal PCR cycle parameters. [Result] The optimal PCR reaction system should contain 2.5μl of 10xPCR buffer, 2.0μl of MgCI2 （25 mmol/L）, 2.0 μl of dNTP mixture （2.5 mmol/L of each dNTP）, 1.0 μl of actin gene primers （10μmol/L）, 1.0μl of 35S promoter primers （10 μmol/L）, 1.5 μl of NOS promoter primers （10 μmol/L） and 0.5 μl of NOS terminator primers （10μmol/L）, 0.1 μg of template DNA, 1.25 U of Taq DNA polymerase; ddH20 was added to the total reaction system of 25μl. The PCR reaction program consisted of pre-denaturing at 94℃ for 5 min; 31 cycles of denaturing at 94℃ for 30 s, annealing at 64.1℃ for 45 s and extension at 72℃ for 50 s; final extension at 72℃ for 10 min. The reaction system optimized with the orthogonal tests could detect as less as 0.1% transgenic component in the tested samples. [Conclusion] The MPCR detection system established in this study can meet the requirements in theory for detecting the genetically modified ingredients in Citrus or the deep-processed products.

[目的]建立柑橘转基因成分的多重 PCR 检测体系。[方法]根据 GenBank 中 pBI121 质粒序列和柑橘(Citrus.)Actin 基因序列,分别设计CaMV35S 启动子、NOS 启动子、NOS 终止子特异引物和 Actin 基因的特异引物,建立能同时检测出 4 种序列的多重 PCR 检测体系,同时通过正交试验确定该体系的最佳引物浓度和比例及 PCR 反应体系中各因素的浓度及反应程序,并对该方法的灵敏度进行验证。[结果]试验得到的最佳MPCR 反应体系为:10×buffer 2.5 μl,25 mmol/L MgCl22.0 μl;dNTP Mixture (2.5 mmol/L each)2.0 μl,10 μmol/L 的 Actin 基因、35S 启动子、NOS 启动子、NOS 终止子引物分别加入 1.0、1.0、1.5、0.5 μl,模板 DNA 0.1 μg,Taq DNA 聚合酶 1.25 U,加 ddH2O 至 25 μl。PCR 反应程序为:94 ℃预变性5 min;94 ℃ 30 s,64.1 ℃ 45 s,72 ℃ 50 s,31个循环;72 ℃ 10 min。试验中,经正交优化后的4重PCR反应灵敏度达0.1%。[结论]该研究建立的MPCR检测体系,理论上已能满足柑橘或其深加工产品的转基因成分检测。