p185^(HER-2)蛋白胞外区的表达及其结合肽的筛选

Expression of p185 ^(HER-2) extracellular domain and screening of its binding peptides

目的 :构建p185 HER -2 蛋白胞外区的原核表达载体 ,实现p185 HER -2 蛋白胞外区的表达。以纯化p185 HER -2 蛋白胞外区为靶 ,从噬菌体肽库中筛选其结合肽 ,用于肿瘤导向治疗。方法 :从含有HER 2全长cDNA的质粒psv2 -cerbB -2 中克隆了人p185 HER -2 蛋白胞外区cDNA ,将此cDNA克隆到pET 30a +表达载体中 ,构建p185蛋白胞外区的表达载体。表达的p185 HER -2 蛋白胞外区通过Zn2 + 螯合层析柱进行纯化。以纯化的p185 HER -2 蛋白胞外区为靶 ,通过淘洗方法进行噬菌体肽库筛选。结果与结论 :构建了p185 HER -2 蛋白胞外区的原核表达载体 ,实现了p185 HER -2蛋白胞外区的高表达。通过Zn2 + 螯合层析柱实现一步纯化 ,p185 HER -2 蛋白胞外区的纯度达到 95 %。从噬菌体随机环七肽库中找到了一组具有核心序列p185 HER -2 蛋白胞外区结合肽。这些p185 HER -2 蛋白胞外区结合肽有可能成为肿瘤治疗的新的候选分子。

Objective: To construct the expression vector of p185 HER-2 extracellular domain, and to find p185 HER-2 binding peptides from phage display peptide library. Methods: The cDNA encoding the p185 HER-2 extracellular domain was amplified by PCR from psv 2-cerbB-2vector, and was inserted into pET-30a+ vector to construct the expression vector. The expressed p185 HER-2 extracellular domain was purified by Zn 2+ chelating chromatography. The purified p185 HER-2 extracellular domain was used as the target to screen phage display peptide library for its binding peptides by panning. Results and Conclusion: The expression vector of p185 HER-2 extracellular domain was constructed and was overexpressed. The purity of p185 HER-2 extracellular domain purified by Zn 2+ chelating chromatography was up to 95%. A group of phage display peptides, which specifically bound p185 HER-2 extracellular domain and had a relatively conserved motif, were selected. These p185 HER-2 extracellular domain binding peptides will be useful for tumor targeting.