Preparing New FMD Subunit Vaccine In Transgenic Plants

Expression foot and mouth disease virus epitope VP1 in transgenic Potato (Solatium tuberosum)To highly produce VP1 epitope of foot and mouth disease virus (FMDV) in transgenic plants, a VPJ gene of "O" serotype FMDV was cloned. Then two plant binary vectors, pBIVP and pBICVP were constructed. In pBIVP, VP1 was placed under the control of the patatin promoter which only has activity in potato tubers. The 3' end of VP1 was fused with the hexapeptide ER (endoplasmic reticulum) retention signal (SEKDEL), and then fused with 3' end of potato proteinase inhibitor II gene (PIN2). Similar to pBIVP, VP1 was driven by patatin promoter, directed ER(endoplasmic reticulum) retention signal peptide, and terminated by 3' UTR of Pin2 in pBICVP . In addition, the VP1 was fused with the CTB gene in pBICVP. The two constructs were introduced into potato via Agrobacterium-mediated transformation, respectively. Results of PCR analysis of kanamycin resistant plants indicated that VP1 has been transferred into potato,and transformation efficiency was about 95%.STUDY A NEW CHLOROPLAST EXPRESSION SYSTEMChloroplast expression system is a new expression system which offers a number of unique advantages including high level of transgene expression, multi-gene expression in single transformation event and transgene containment due to maternal inheritance. However, the homologous recombinant plastid DNA of transgenic plant is the time cosuming using the traditional selection method. Also we proposed the wild type need plastid DNA could not fully removed using the antibiotics selection method, thereafter, results in unstable expression of target protein in the transgenic plant.To overcome the shortcoming of the long period be used to get the stable transgenic plants, interaction between Barnase and Barstar were introduced in construction of a novel chloroplast expression system. A novel chloroplast expression vector containing Barstar gene was constructed, and used for transformation of tobacco using microprojectile bombardment. After bombardment, transgenic plants were obtained after three months.Meanwhile, a plant binary vector, which containing Barbase gene with chloroplast transporting signal peptide, was constructed and introduced into tobacco via Agrvbacterium-mediated transformation. The selection and analysis of transgenic plants were going on.