p185HER-2蛋白胞外区的表达及其结合肽的筛选

目的：构建p185^HER-2蛋白胞外区的原核表达裁体，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psv^2-cerbB-2中克隆了人p185^HER-2蛋白胞外区cDNA，将此cDNA克隆到pET-30a 表达栽体中，构建p185蛋白胞外区的表达栽体。表达的p185^HER-2蛋白胞外区通过Zn^2 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茵体肽库筛选。结果与结论：构建了p185^HER-2蛋白胞外区的原核表达栽体，实现了p185^HER-2蛋白胞外区的高表达。通过Zn^2 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。

Expression of p185HER-2 extracellular domain and screening of its binding peptides

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.