Banerjee S, Spector D J
Department of Pathology, Royal Veterinary College, University of London, U.K.
J Gen Virol. 1992 Oct;73 ( Pt 10):2631-8. doi: 10.1099/0022-1317-73-10-2631.
We examined the effect of DNA template topology on the transcription of immediate early (E1a), early (E1b) and late (pIX) adenovirus genes in vitro. Transcription in whole cell extracts was measured by quantitative hybridization to end-labelled DNA and protection of hybrids from S1 nuclease digestion. Two- to fourfold more E1a RNA was synthesized from supercoiled, compared to linear, DNA templates. Similarly, transcription of the E1b gene was stimulated three- to sevenfold when the template was supercoiled. In contrast, RNA synthesis from the late pIX gene was found to be independent of DNA topology. These results show that DNA topology affects transcription in a promoter-specific manner.
我们在体外研究了DNA模板拓扑结构对腺病毒即刻早期（E1a）、早期（E1b）和晚期（pIX）基因转录的影响。通过与末端标记的DNA进行定量杂交以及保护杂交体免受S1核酸酶消化来测量全细胞提取物中的转录。与线性DNA模板相比，超螺旋DNA模板合成的E1a RNA多两到四倍。同样，当模板为超螺旋时，E1b基因的转录受到三到七倍的刺激。相比之下，发现晚期pIX基因的RNA合成与DNA拓扑结构无关。这些结果表明，DNA拓扑结构以启动子特异性方式影响转录。
