温敏类弹性蛋白多肽的基因设计及重组克隆表达

Gene Design and Recombinant Cloning and Expression of Thermal-Sensitive Elastin-like Polypeptides

温敏类弹性蛋白多肽(elastin-like polypeptides, ELPs)作为新型的药物载体,在肿瘤治疗中具有广阔的应用前景。本研究根据大肠杆菌密码子的偏好性和简并性,将高度连续重复氨基酸的多种遗传密码引入基因序列中,利用依次插入单体基因和递归定向连接技术,成功构建了以缬氨酸为客座氨基酸的ELPs基因的表达质粒库,即p ET28-ELP-V_5～pET28-ELP-V_(50)。将pET28-V_(50)转化至表达宿主Escherichia coli BL21(DE3)中,经重组菌的培养和IPTG诱导,SDS-PAGE结果显示ELP-V_(50)在大肠杆菌中成功获得了可溶性表达,与预期分子量大小一致。本研究为进一步构建不同分子量的ELPs基因库提供了新的思路,并为重组表达获得特定相变特性的多肽分子奠定了基础。

Thermal-sensitive elastin-like polypeptides(ELPs) as novel drug carriers, have a broad application prospect in cancer treatment. According to codon preference and degeneracy of Escherichia coli, in this study, we introduced several genetic codes of highly continuous repetition amino acids into the gene sequences. Using technologies of insertion of monomer gene and recursive directional ligation, we successfully constructed recombinant expression plasmid library of ELPs with valine as guest amino acid(p ET28-ELP-V5~p ET28-ELP-V50). Then, p ET28-ELP-V50 was transformed into the expression host E. coli BL21(DE3). After recombinant strain culture and IPTG induction, SDS-PAGE results showed that ELP-V50 was successfully soluble expressed in E. coli BL21(DE3), consistent with the expected molecular weight. This work would provide new idea for further construction of ELPs gene library with different molecular weights, and contribute basis for recombinant expression to obtain polypeptides with specific phase transition characteristics.