PLANT EXPRESSIONS OF CYTOKINES AND IIST APPILICATIONS FOR ANIMAL DISEASE CONTROL

本研究的目的是在植物中表达具有生物活性的动物蛋白，并将重组蛋白应用于动物疾病控制。我们使用转基因植物和植物病毒载体茎来表达动物基因。通过农杆菌介导的转化，我们引入了两种人干扰素α亚型（IFNα2b和IFNα8）的cdna。northern blot和酶免疫分析证实了引入基因的表达。在转基因马铃薯中检测到10 ~ 500 IU/g的IFN8。在牛白血病病毒感染中，肿瘤坏死因子α参与了其发病机制，特别是控制了感染动物的病毒负荷。我们还克隆了一种蜱唾液巨蛋白、一种蜱丝氨酸蛋白酶和一种蜱质表面抗原的基因，这些基因有望在植物中表达并用于疾病控制方法。将三叶草黄脉病毒cDNA与35S启动子组合为pC1YVV，建立了植物表达体系。证实该病毒载体可表达绿色荧光蛋白。将INF8 cDNA导入该载体，检测其表达。然而，经酶免疫测定，该重组病毒感染的植物没有表达任何产物，这可能是由于病毒载体没有保留cDNA。动物基因在该系统中的稳定表达有待进一步研究。

The aim of this study is to express bioactive animal proteins in plants and to apply the recombinant proteins for animal disease control. We used transgenic plant and plant viral vector stems for expression of animal genes.By Agrobacterium-mediated transformation, we introduced cDNAs of two subtypes of human interferon α (IFNα2b and IFNα8). Expression of the introduced genes was confirmed by northern blot analysis and enzyme immunoassay. Ten to 500 IU/g of IFN8 were detected in transgenic potatoes.In bovine leukemia virus infection, tumor necrosis factor α was revealed to be involved in pathogenesis, especially control of viral burden in infected animals. We also clones genes for a tick salivary grand protein, tick serine proteases, and a piroplasm surface antigen that are expected to be expressed in plant and used for method of disease controls.A plant expression system based on clover yellow vein virus has been developed by combining its cDNA and 35S promoter as pC1YVV. Expression of green fluorescence protein by this virus vector was confirmed. INF8 cDNA was introduced into this vector and its expression was tested. However, plant infected with this recombinant virus did not express any product as tested by enzyme immunoassay, provably because the viral vector had not retained the cDNA. Further investigation will be required for stable expression of animal genes in this system.