Sassone-Corsi P, Hen R, Borrelli E, Leff T, Chambon P
Nucleic Acids Res. 1983 Dec 20;11(24):8735-45. doi: 10.1093/nar/11.24.8735.
We have investigated the requirement for sequences located upstream from the TATA box for efficient transcription from the Adenovirus-2 (Ad2) E1A promoter. A series of deletions located within the E1A promoter upstream sequences were introduced into recombinants which contain or do not contain the E1A structural sequences. The amount of E1A-specific RNA produced after transfection into HeLa cells was determined by quantitative S1 nuclease analysis. We demonstrate that sequences located more than 231 bp upstream from the E1A capsite are required for efficient transcription from the E1A promoter. However, the requirement for these stimulatory sequences is less pronounced in recombinants which contain the E1A structural sequences than in those in which these sequences have been deleted. We demonstrate also that these Ad2 stimulatory sequences activate transcription in cis when inserted upstream from the heterologous -34 to +33 Ad2 major late promoter (Ad2MLP) element which is otherwise inactive when transfected into HeLa cells. These results suggest that the 270 bp Ad2 left-terminal segment contains an enhancer-like element.
我们研究了腺病毒2型(Ad2)E1A启动子高效转录所需的位于TATA框上游的序列。将一系列位于E1A启动子上游序列内的缺失片段引入含有或不含有E1A结构序列的重组体中。通过定量S1核酸酶分析确定转染到HeLa细胞后产生的E1A特异性RNA的量。我们证明,从E1A启动子高效转录需要位于E1A帽位点上游超过231 bp的序列。然而,对于这些刺激序列的需求在含有E1A结构序列的重组体中不如在那些已删除这些序列的重组体中明显。我们还证明,当这些Ad2刺激序列插入到异源的-34至+33 Ad2主要晚期启动子(Ad2MLP)元件上游时,可顺式激活转录,而该元件在转染到HeLa细胞时原本是无活性的。这些结果表明,270 bp的Ad2左末端片段含有一个类增强子元件。