Bell S D, Brinkman A B, van der Oost J, Jackson S P
Wellcome Trust and Cancer Research Campaign Institute of Cancer and Development Biology, Cambridge, UK.
EMBO Rep. 2001 Feb;2(2):133-8. doi: 10.1093/embo-reports/kve021.
Transcription from many archaeal promoters can be reconstituted in vitro using recombinant TATA-box binding protein (TBP) and transcription factor B (TFB)--homologues of eukaryal TBP and TFIIB--together with purified RNA polymerase (RNAP). However, all archaeal genomes sequenced to date reveal the presence of TFE, a homologue of the alpha-subunit of the eukaryal general transcription factor, TFIIE. We show that, while TFE is not absolutely required for transcription in the reconstituted in vitro system, it nonetheless plays a stimulatory role on some promoters and under certain conditions. Mutagenesis of the TATA box or reduction of TBP concentration in transcription reactions sensitizes a promoter to TFE addition. Conversely, saturating reactions with TBP de-sensitizes promoters to TFE. These results suggest that TFE facilitates or stabilizes interactions between TBP and the TATA box.
利用重组的TATA盒结合蛋白（TBP）和转录因子B（TFB）——真核生物TBP和TFIIB的同源物——以及纯化的RNA聚合酶（RNAP），可以在体外重建许多古细菌启动子的转录过程。然而，迄今为止测序的所有古细菌基因组都显示存在TFE，它是真核生物通用转录因子TFIIE的α亚基的同源物。我们发现，虽然TFE在体外重建系统中并非转录绝对必需的，但它在某些启动子和特定条件下仍发挥刺激作用。TATA盒的诱变或转录反应中TBP浓度的降低会使启动子对TFE的添加敏感。相反，用TBP使反应饱和会使启动子对TFE不敏感。这些结果表明，TFE促进或稳定了TBP与TATA盒之间的相互作用。
