摘要
含有人成纤维细胞干扰素(IFNβ)基因编码序列的HindⅡ片段,去掉了IFNβ基因5′全部侧翼调控序列,与SV40早期区RNA起始部位下游60个bp处连接,与可选择标记二氢叶酸还原酶(dhfr)基因一道共转化dhfr缺陷的中国地鼠卵(CHO)细胞,经过初步筛选,在未经病毒等诱导条件下,在转化细胞株中测到构成性表达水平为852U/2×10~6细胞·ml·48小时的IFNβ干扰素活性。
HindII fragment encloding human fibroblast interferon (IFNβ) gene coding sequence was funsed at 60 bp downstream from the RNA start site of SV40 early gene to be a constitutive expression plasmid pSVEβ This recombinant plasmid was transfected into the dihydrofolatc reductase (dhfr)-deficient Chinese hamster ovary (CHO) calls together with a selectable dhfr gene.About half of transformants continuously secreted IFNβ into the supernatant without in-ducement.One of the subclone transformants constitutively produced up to 852U IFNβ/2×1 106 cells/ml.48hr in commen medium.
关键词
IFNβ基因
启动子
组成性表达
IFNβ gene,SV40 early promoter,Constitutive expression
