Rappleye C A, Roth J R
Department of Biology, University of Utah, Salt Lake City 84112, USA.
J Bacteriol. 1997 Sep;179(18):5827-34. doi: 10.1128/jb.179.18.5827-5834.1997.
A new Tn10-based transposon has been constructed and used to isolate insertion mutations with tetracycline-conditional phenotypes. Classes of mutants include conditional lethal mutations, conditional auxotrophs, and conditional mutants of the eut (ethanolamine utilization) operon. The described mutations were made with a new derivative of Tn10dTet that we have called Tn10d(T-POP). Others have noted that transposon Tn10dTet directs weak tetracycline-inducible transcripts out of both ends of the element into adjacent sequences. We have increased this level of outward transcription from Tn10dTet by selecting deletion mutations within the element that presumably remove transcription-termination signals. Insertion of the Tn10d(T-POP) element within an operon disrupts the target gene and makes expression of distal genes dependent on induction of outward transcription by tetracycline. Insertion mutations made with Tn10d(T-POP) can cause tetracycline-correctable conditional phenotypes based on expression of distal genes.
一种基于Tn10的新型转座子已构建成功，并用于分离具有四环素条件表型的插入突变。突变体类别包括条件致死突变、条件营养缺陷型以及乙醇胺利用（eut）操纵子的条件突变体。所描述的突变是用我们称为Tn10d(T-POP)的Tn10dTet新衍生物产生的。其他人已注意到转座子Tn10dTet可将弱四环素诱导转录本从元件两端导向相邻序列。我们通过选择元件内可能去除转录终止信号的缺失突变，提高了Tn10dTet向外转录的水平。Tn10d(T-POP)元件插入操纵子内会破坏靶基因，并使远端基因的表达依赖于四环素诱导的向外转录。用Tn10d(T-POP)产生的插入突变可基于远端基因的表达导致四环素可纠正的条件表型。
