通过聚合酶链式反应 (PCR)技术 ,以戊肝病毒cDNA为模板将开读框架 3的基因片段扩增并克隆入载体pUC18中。再对扩增片段进行酶切鉴定及测序 ,结果表明此片段与膜板序列的同源性达到 99%以上。将此片段克隆后通过一系列分子生物学技术装入真核胞内表达载体PPIC3及分泌性载体PPIC9中 ,并对载体进行酶切鉴定证实外源基因插入的正确性。最终完成表达载体的构建 The gene fragment of open reading frame 3 was amplified and cloned into vector pUC18 by polymerase chain reaction (PCR) using the hepatitis E virus cDNA as a template. Then, the amplified fragments were identified by restriction enzyme digestion and sequencing. The results showed that the homology of this fragment with the membrane sequence was over 99%. This fragment was cloned and then inserted into eukaryotic expression vector PPIC3 and PPIC9 by a series of molecular biology techniques. The vector was digested with restriction endonuclease to confirm the correctness of foreign gene insertion. Finally, the construction of the expression vector was completed