摘要
组织纤溶酶原激活剂（ｔＰＡ）是一种较理想的溶血栓药物，本研究采用其突变体———长效组织纤溶酶原激活剂（ＬＡｔＰＡ）的ｃＤＮＡ作为目的基因，将它插入羊β乳球蛋白（ＢＬＧ）基因起始密码之前，使ＬＡｔＰＡ的转录、翻译受控于ＢＬＧ基因的５′、３′序列，再将所构建的ＢＬＧＬＡｔＰＡ用显微注射方法建立转基因鼠，经点杂交筛选和Ｓｏｕｔｈｅｒｎ印迹鉴定，获得２只ＬＡｔＰＡ基因整合阳性鼠，并在阳性母鼠乳汁中检测到有溶纤活性的ＬＡｔＰＡ表达，表达水平１５μｇ／ｍｌ。在这两只转基因鼠的９只Ｆ１代子鼠中，有５只是阳性的，ｔＰＡ表达水平维持在１～２μｇ／ｍｌ，ＢＬＧｔＰＡ融合基因整合到小鼠基因组，能稳定地遗传给子代。
An exogenous gene was expressed in the mammary epithelium of transgenic mice in the hope that the encoded protein can be able to secrete into milk.The transgenic mice carrying the promoter and upstream regulatory sequences from the sheep BLG gene which were fused to cDNA encoding human tissue plasminogen activator (tPA) with its endogenous secretion signal sequence were generated.The hybrid genes were microinjected into mouse embryos.Two mouse were identified as being transgene by Southern blot.Milk obtained from lactating females contains biologically active tPA, and concentration was calculated to be about 1 5μg/ml.This result establishes the feasibility of secretion into the milk of transgenic animals for production of biologically active tPA proteins,and may provide a powerful method to produce such proteins on a large scale.
出处
《生物工程学报》
CAS
CSCD
北大核心
1998年第4期372-376,共5页
Chinese Journal of Biotechnology
基金
国家863计划资助
