人肿瘤坏死因子可溶性受体I cDNA的克隆及其在原核和真核细胞中的表达

Cloning of Soluble Human TNFR-I cDNA and Its Expression in Prokaryotic and Eukaryotic Cells

以人的胎盘总ＲＮＡ为模板，用ＲＴ－ＰＣＲ的方法，获得人肿瘤坏死因子可溶性受体Ｉ（ｓｈＴＮＦＲ－Ｉ）的ｃＤＮＡ，并对其进行全序列分析，在此基础上构建了原核及真核的表达载体。

TNFa have many biological functions,such as immunity, inflammation and cytotoxicity. Most of these functions are mediated by the TNF receptor I. This receptor has two forms, the soluble receptor and membrane binding one. The soluble form has been detected in serum and urine of patients on regular hemodialysis. It can inhibited the specific binding of human TNF to its surface receptor. A cDNA fragment encoding for soluble form of TNFR - I was obtained by RT-PCR from human placenta mRNA and then sequenced. It was further cloned into the mammalina expression vector - PCEP4 and E. colt expression vectorpRSET-B. The human 293 cells were transfected by recombinant vector,the activity of sTNFR- I was detected in the conditioned medium. The protein products are expressed in E. coli DE3 and have been pruified. The results of present study will benifit the researches for the molecular mathanism of TNF'S functions and the therapy of many relevant diseases.