Liu Q Y, Summers W C
Department of Molecular Biophysics, School of Medicine, Yale University, New Haven, Connecticut 06510.
J Virol. 1989 Dec;63(12):5062-8. doi: 10.1128/JVI.63.12.5062-5068.1989.
We have demonstrated that gene expression from the promoter of the Epstein-Barr virus (EBV) MS gene with its upstream sequence is inducible by 12-O-tetradecanoylphorbol-13-acetate (TPA). By transfecting mammalian cells with plasmids in which the MS promoter and its upstream sequence are linked to the bacterial chloramphenicol acetyltransferase gene, we have shown that treatment of the cells with TPA stimulates the expression of chloramphenicol acetyltransferase activity in both EBV-negative and -positive cell lines. This TPA response requires the cis-acting sequence between nucleotides 84440 and 85046 of the EBV genome, located either upstream or downstream of the MS promoter. The TPA induction is at the transcriptional level. When this sequence is linked to the promoter of the human herpesvirus 1 thymidine kinase gene, it can also enhance the expression of, and confer TPA responsiveness on, the thymidine kinase promoter. By constructing and transfecting mutants with 5' and 3' deletions, we have identified two TPA-responsive elements, one located between -726 and -690 and the other located between -603 and -546 relative to the transcription start site. These two sequences do not contain any homology to the previously defined elements for TPA response and may play an important role in EBV induction by TPA.
我们已经证明，带有上游序列的爱泼斯坦-巴尔病毒（EBV）MS基因启动子的基因表达可被12-O-十四酰佛波醇-13-乙酸酯（TPA）诱导。通过用质粒转染哺乳动物细胞，其中MS启动子及其上游序列与细菌氯霉素乙酰转移酶基因相连，我们已经表明，用TPA处理细胞可刺激EBV阴性和阳性细胞系中氯霉素乙酰转移酶活性的表达。这种TPA反应需要EBV基因组中位于MS启动子上游或下游的核苷酸84440至85046之间的顺式作用序列。TPA诱导作用发生在转录水平。当该序列与人类疱疹病毒1胸苷激酶基因的启动子相连时，它也可以增强胸苷激酶启动子的表达并赋予其TPA反应性。通过构建和转染具有5'和3'缺失的突变体，我们鉴定出两个TPA反应元件，一个位于相对于转录起始位点的-726和-690之间，另一个位于-603和-546之间。这两个序列与先前定义的TPA反应元件没有任何同源性，可能在TPA诱导EBV中起重要作用。
