Schilling L J, Farnham P J
McArdle Laboratory for Cancer Research, University of Wisconsin, Madison 53706.
Mol Cell Biol. 1989 Oct;9(10):4568-70. doi: 10.1128/mcb.9.10.4568-4570.1989.
In vitro reactions identified a transcription initiation site located 740 nucleotides upstream of the dihydrofolate reductase translational start. Transcription from this site proceeded in the direction opposite to that of dihydrofolate reductase mRNA. Deletion mapping indicated that this new promoter can be separated from the dihydrofolate reductase promoter and that separation increased transcription at -740. Transcripts that initiate at -740 were also detected in cellular RNA, indicating that this is a bona fide transcription initiation site in vivo.
体外反应确定了一个转录起始位点，该位点位于二氢叶酸还原酶翻译起始位点上游740个核苷酸处。从该位点开始的转录方向与二氢叶酸还原酶mRNA的转录方向相反。缺失图谱分析表明，这个新的启动子可以与二氢叶酸还原酶启动子分离，并且这种分离增加了-740位点处的转录。在细胞RNA中也检测到了从-740位点起始的转录本，这表明这是体内一个真正的转录起始位点。
