生物技术通报 ›› 2016, Vol. 32 ›› Issue (2): 84-89.doi: 10.13560/j.cnki.biotech.bull.1985.2016.02.011

• 研究报告 • 上一篇    下一篇

人IL-24基因原核表达载体的构建及蛋白的表达纯化

喻放1, 杨忠华1, 范汉东2, 左振宇1   

  1. 1.武汉科技大学,武汉430081;2.杭州师范大学衰老研究所,杭州 310036
  • 收稿日期:2015-04-22 出版日期:2016-02-24 发布日期:2016-02-25
  • 作者简介:喻放,男,硕士研究生,研究方向:分子生物学;E-mail:358311135@qq.com
  • 基金资助:
    湖北省自然科学基金项目(2014CFB802)

The Construction of Prokaryotic Expression Vector for Human Gene IL-24 and Expression and Purification of Its Protein

YU Fang1, YANG Zhong-hua1, FAN Han-dong2, ZUO Zhen-yu1   

  1. (1.Wuhan University of Science and Technology,Wuhan 430081;2.Institute of Aging Research of Hangzhou Normal University,Hangzhou 310036)
  • Received:2015-04-22 Published:2016-02-24 Online:2016-02-25

摘要: 构建人白细胞介素24(IL-24)原核表达载体并利用ELP-Intein系统表达纯化可溶性的IL-24蛋白。通过PCR扩增不含信号肽的人IL-24基因,将IL-24基因插入pET-ELP-Intein质粒构建重组表达载体pET-ELP-Intein-IL-24。将重组质粒转化至E.coli BLR(DE3),20℃下经IPTG诱导表达。利用ELP蛋白在不同温度下发生相变的特点和Intein蛋白的自切割反应纯化可溶性IL-24蛋白,将纯化得到的IL-24蛋白进行Western blot鉴定。用Annexin V-FITC/PI细胞凋亡检测试剂盒检测IL-24蛋白的生物学活性。成功构建了重组表达载体pET-ELP-Intein-IL-24,第一次通过原核表达方法表达并纯化出了可溶性的IL-24蛋白。Western blot检测显示目的蛋白能与IL-24抗体特异性结合,表明纯化出的蛋白确实为IL-24蛋白。细胞凋亡检测实验证明IL-24蛋白能显著地诱导hepG2细胞发生凋亡。

关键词: 白细胞介素24, 质粒构建, 原核表达, 蛋白纯化

Abstract: This work aims to construct a prokaryotic expression vector for human gene IL-24, and express and purify soluble IL-24 protein via ELP-Intein system.The human gene IL-24 without signal peptide was amplified by PCR and cloned into vector pET-ELP-Intein, and the recombinant expression vector pET-ELP-Intein-IL-24 was constructed.The recombinant plasmid was transformed to Escherichia coli BLR(DE3), and the expression was induced at 20℃ by IPTG.The soluble IL-24 protein was purified based on the transformation of ELP protein at different temperatures and the self-cleavage reaction of Intein protein.The purified protein was identified by Western blot.The bioactivity of IL-24 protein was measured by Annexin V-FITC/PI apoptosis detection kit.The recombinant expression vector pET-ELP-Intein-IL-24 was successfully constructed, and the soluble IL-24 protein was expressed for the first time by prokaryotic vector and purified.Western blot analysis showed the target protein specifically bound with IL-24 antibody, which proved that the purified protein was indeed IL-24 protein.Apoptosis detection experiment confirmed that IL-24 protein significantly induced the apoptosis of hepG2 cells.

Key words: IL-24, recombinant plasmid construction, prokaryotic expression, protein purification