人TPO全长分子在大肠杆菌中的表达及其活性分析

Expression and activity assay of human TPO from E.coli

利用反转录－ＰＣＲ从人胎肝中获得编码血小板生成素（ｈＴＰＯ）全长ｃＤＮＡ，在大肠杆菌中表达了人ＴＰＯ全长分子。电镜观察结果，目的蛋白在菌体内以包涵体形式存在，表达量约占菌体总蛋白的２７％；表达产物经初步纯化后，与ＣＯＳ－７细胞中表达的人ＴＰＯ３５３个氨基酸全长分子分别做ＢＡＬＢ／ｃ小鼠体内活性分析，结果表明，原核与真核系统表达的ＴＰＯ均具有明显促进血小板生成的作用。这为进一步研究ＴＰＯ的糖基化与其生物学活性及半衰期关系打下基础。

We had previously cloned the whole length cDNA of human thrombopoietin(hTPO) from fetal liver by RT PCR.In this study,we reported that a human TPO was expressed in E.coli .The target protein accounted for 27% of total bacterial protein and was in the form of inclusion.After preliminary purification of the TPO,we treated peritoneally BALB/c mice with TPO for 8 days and accounted peripheral platelets in mice on the 9th day.At the same time,activities of the TPO was compared with that expressed in COS 7 cells.The results showed that the two kinds of proteins had played an active role in increasing platelet production,which would provide a basis for further studies on glycosylation,other activities and half life of TPO.