目的:构建尘螨变应原Der f1植物表达载体并侵染烟草叶片表达。方法:从保存的含pET28a(+)-Der f1的甘油菌株中扩增Der f1基因,并克隆到质粒载体中,提取质粒,进行测序;以ClaⅠ、SalⅠ双酶切,将Der f1基因克隆到马铃薯X病毒(PVX)载体中,构建植物病毒表达载体;将PVX-Der f1转化脓杆菌,挑取Kan、Tet抗性阳性的菌株侵染烟草叶片进行蛋白表达,采用SDS-PAGE和Western blot对表达蛋白进行鉴定和分析。结果:经SDS-PAGE分析,有4株烟草叶片蛋白提取物在34Mr处有特异性蛋白条带;经Western blot进一步验证其变应原,结果显示,烟草叶片中获得的重组蛋白在34Mr处与阳性血清发生特异性结合,而与阴性血清并不发生结合。结论:成功构建了植物病毒表达载体PVX-Der f1并获得表达,为尘螨变应原Der f1的研究提供新思路。
Objective:To construct the plant expression vector of Der fl allergen of Dermatophagoides pteronyssinu and expression in tobacco lamina. Methods:The Der fl gene was amplified from the glycerin bacterium which contained pE3ESa( + )-Der fl plasmid, cloned into the pMD 19-T plasmid, and then sequenced. The Der fl gene was digested by Cla Ⅰ and Sal Ⅰ , and cloned into potato virus X (PVX) to construct plant expression vector PVX-Der fl, and then was transformed agrobacterium tumefaciens. The positive one was selected to infect tobacco lamina for expressing tan'get protein. The protein was identified and analysed by SDS-PAGEand Western blot. Results: Digestion and sequence analysis confirmed that the plant expression vector was correct, and the SDS-PAGE and Western blot results showed that the molecular weight of the protein was about 34Mr and it could specific binding with positive serum. Conclusion: The plant expression vector of Der fl is successfully constructed and the recombinant protein is also produced.