Connelly S, Manley J L
Department of Biological Sciences, Columbia University, New York, New York, 10027.
Mol Cell Biol. 1989 Nov;9(11):5254-9. doi: 10.1128/mcb.9.11.5254-5259.1989.
A region in the adenovirus major late promoter (MLP) containing a CCAAT consensus sequence can direct transcription termination of RNA polymerase II, a mechanism that possibly prevents transcriptional interference from upstream genes. Using a chimeric plasmid template that contains the MLP directing expression of the simian virus 40 early region, we showed that an inserted oligonucleotide containing only 13 base pairs of MLP sequences, including the CCAAT box, is capable of inducing transcription termination in an orientation-dependent, position-independent manner. Point mutations within the CCAAT-specific protein-binding site abolished this effect, while a base substitution outside of this region did not affect termination. These data suggest that termination is mediated by a CCAAT box-binding protein. Several other transcription factor-binding sites do not, however, cause termination, suggesting that this may be a relatively specific property of a CCAAT-binding protein.
腺病毒主要晚期启动子（MLP）中含有CCAAT共有序列的区域可指导RNA聚合酶II的转录终止，这一机制可能会阻止上游基因的转录干扰。使用包含指导猿猴病毒40早期区域表达的MLP的嵌合质粒模板，我们发现仅包含13个碱基对MLP序列（包括CCAAT框）的插入寡核苷酸能够以方向依赖、位置独立的方式诱导转录终止。CCAAT特异性蛋白结合位点内的点突变消除了这种效应，而该区域外的碱基替换不影响终止。这些数据表明终止是由CCAAT框结合蛋白介导的。然而，其他几个转录因子结合位点不会导致终止，这表明这可能是CCAAT结合蛋白相对特异的特性。
