HBV基因中GRE相关DNA片段能介导多种激素对转录的调节作用

本文用寡聚核苷酸介导的定点突变改造乙型肝炎病毒(HBV)基因中的糖皮质激素应答元件(glucocorticoid response element,GRE),并将改变前后的GRE相关DNA片段与氯霉素乙酰基转移酶(CAT)基因融合,与多种激素受体的表达质粒共转染肝细胞,分别用不同的激素处理,测定CAT基因的表达活性以确定HBV上GRE相关DNA片段对各种激素的应答。结果表明HBV上GRE相关DNA片段能介导异源基因对糖皮质激素、孕激素和雌激素的应答。不含Enl的GRE相关片段与CAT基因融合后,在不加激素诱导的情况下,CAT基因活性明显降低。

The GRE-associated DNA Fragment of HBV Can Medate Heterologous Gene to Response for Several Hormones

The site-directed mutagenesis mediated by oliogonucleotide was made to change the structure of the glucocor-ticoid response element(GRE) of HBV. The DNA fragments containing natural GRE or mutant GRE were fused to chloramphenical acetyltransferease (CAT) gene. The human liver-derived cell line hepG2 was co-transfected by hormone receptor expression plasmids and CAT reporter plasmids. The results of CAT assay showed that the GUE-associated DNA fragment of HBV was able to mediate heterologous gene to response for dexamethasone,progesterone and estradiol. The fusion of the CAT gene and the GRE-associated DNA fragment without En I decreased the activity of the CAT gene in the absence of hormones.