摘要
目的 :克隆VEGF受体KDR基因膜外 5 7区 ,探讨其生物学活性。方法 :提取脐静脉血管内皮细胞总RNA ,克隆KDR基因膜外部分 5 7区 ,并使之在QIA表达系统进行表达 ;镍柱亲和层析纯化、复性、生物学活性鉴定。结果 :该系统能表达KDR基因片段 ,表达量约占菌体蛋白总量的 5 %左右。经复性 ,可溶性蛋白具有与VEGF特异结合功能 ,并能抑制VEGF促使脐静脉内皮细胞增殖和鸡胚绒毛尿囊膜血管生成的作用。结论 :KDR基因片段能在QIA表达系统中得到表达 ,复性后表达蛋白具有与VEGF结合的生物学功能。
Objective: To clone cDNA encoding Ⅴ-Ⅶ extra-cellular domains of VEGF receptor KDR and investigate biological activity of the recombinant protein. Methods: Total RNA from the umbelical venous endothelial cells was obteined. From it, KDR cDNA was cloned into the BamH1 and Kpn 1 sites of pQE31 and made expressed with induction of IPTG. The recombinant protein was purified, refolded and determined for its biological activities. Results: The expression system could express the human recombinant extra-cellular protein of KDR with expression level accounting for 5% of the total bacterial protein. After renaturation, the recombinant protein could bind to 125 I-VEGF and suppress endothelial cell proliferation and angiogenesis of chick chorioallantoic membrance induced by VEGF. Conclusion: Human KDR extra-cellular domain can be expressed in E coli and after being refolded, has an action of binding to VEGF.
出处
《中国肿瘤生物治疗杂志》
CAS
CSCD
2001年第3期173-177,共5页
Chinese Journal of Cancer Biotherapy
基金
上海市卫生局课题资金资助 ( 992 4)
