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针对丙型肝炎病毒ＲＮＡ（ＨＣＶＲＮＡ）的５′非编码区和部分Ｃ区的二级结构，设计并合成了四个不同的锤头型核酶（ｒｉｂｏｚｙｍｅＡ，ｒｉｂｏｚｙｍｅＢ，ｒｉｂｏｚｙｍｅＣ１，ｒｉｂｏｚｙｍｅＣ２）．首先应用体外切割实验筛选出作用于ＨＣＶＲＮＡ起始密码子上游ＧＴＡ↓位点的核酶ＲｚＡ有较好的活性．为初步验证核酶ＲｚＡ在细胞内的切割活性，经脂质体介导，将ＲｚＡＲＮＡ与另一携带该核酶靶基因的质粒表达载体ｐＣｌｎｅｏｌｕｃｉｆｅｒａｓｅ（载体中荧光素酶基因受核酶靶基因的调控）共转染ＨｅｐＧ２细胞．通过测定荧光素酶基因的表达证实了核酶在细胞内有较好的切割活性．在此实验基础上，把ＲｚＡ基因克隆至ｐＣｌｎｅｏ质粒表达载体中，再次经脂质体介导，将重组的表达载体ｐＣｌｎｅｏＲｚＡ与携带该核酶靶基因的质粒表达载体ｐＣｌｎｅｏｌｕｃｉｆｅｒａｓｅ共转染ＨｅｐＧ２细胞，获得了更好的切割效果．
Four different hammerhead ribozymes ribozymeB (ribozymeB, ribozymeC1, ribozymeC2) were designed and synthesized according to the secondary structure of the 5 ’non-coding region and partial region C of hepatitis C virus RNA. First, the in vitro cleavage assay was used to screen out the ribozyme RzA that acts on the GTA ↓ upstream of the HCV RNA initiation codon. To initially verify the ribozyme RzA cleavage activity in the cell, mediated by liposomes, the RzA RNA and another carrying the ribozyme target gene plasmid expression vector pCl neo luciferase (vector luciferase gene by Ribozyme target gene regulation) co-transfected HepG2 cells. By measuring the luciferase gene expression confirmed ribozyme in the cell has better cutting activity. On the basis of this experiment, the RzA gene was cloned into pCl neo plasmid expression vector, and again mediated by liposome, the recombinant expression vector pCl neo RzA and carry the ribozyme target gene plasmid expression vector pCl neo luciferase co-transfected HepG2 cells, get a better cutting results.