Two transcription factors related with the eucaryal transcription factors TATA-binding protein and transcription factor IIB direct promoter recognition by an archaeal RNA polymerase
Two transcription factors related with the eucaryal transcription factors TATA-binding protein and transcription factor IIB direct promoter recognition by an archaeal RNA polymerase
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DOI：
10.1074/jbc.271.47.30144
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发表时间：
1996-11-22
影响因子：
4.8
通讯作者：
Thomm, M
中科院分区：
文献类型：
--
作者：
Hausner, W;Wettach, J;Thomm, M
我们曾报道过甲烷球菌和火球菌的无细胞转录依赖于两种古细菌转录因子：古细菌转录因子A（aTFA）和古细菌转录因子B（aTFB）。在火球菌基因组中，已检测到编码真核转录因子TATA结合蛋白（TBP）和TFIIB的基因。我们报道了大肠杆菌合成的TBP和TFIIB的热球菌同源物能够在无细胞转录反应中替代内源性aTFB和aTFA。针对古细菌TBP和TFIIB产生的抗体结合aTFB和aTFA级分中相同分子量的多肽。这些数据将aTFB鉴定为古细菌TBP并且将aTFA鉴定为TFIIB的古细菌同源物。在热球菌谷氨酸脱氢酶（gdh）启动子处，这两种细菌产生的转录因子和内源RNA聚合酶足以指导转录的准确和主动起始，DNA酶I保护实验揭示了火球菌-TBP在位置-20和-25之间产生特征足迹。34以gdh启动子的TATA盒为中心，火球菌属-TFIIB不结合TATA盒，但与火球菌属-TBP协同结合，产生范围从位置-19至-42的延伸的DNA酶I足迹模式。这些数据表明TFIIB的火球菌属同源物与TBP-启动子二元复合物缔合作为其真核对应物，但与真核TFIIB相反，它导致保护延伸到TATA盒上游区域。
We reported previously that cell-free transcription in the Archaea Methanococcus and Pyrococcus depends upon two archaeal transcription factors, archaeal transcription factor A (aTFA) and archaeal transcription factor B (aTFB), In the genome of Pyrococcus genes encoding putative homologues of eucaryal transcription factors TATA-binding protein (TBP) and TFIIB have been detected, Here, we report that Escherichia coli synthesized Pyrococcus homologues of TBP and TFIIB are able to replace endogenous aTFB and aTFA in cell-free transcription reactions, Antibodies raised against archaeal TBP and TFIIB bind to polypeptides of identical molecular mass in the aTFB and aTFA fraction. These data identify aTFB as archaeal TBP and aTFA as the archaeal homologue of TFIIB, At the Pyrococcus glutamate dehydrogenase (gdh) promoter these two bacterially produced transcription factors and endogenous RNA polymerase are sufficient to direct accurate and active initiation of transcription, DNase I protection experiments revealed Pyrococcus-TBP producing a characteristic footprint between position -20 and -34 centered around the TATA box of gdh promoter, Pyrococcus-TFIIB did not bind to the TATA box but bound cooperatively with Pyrococcus-TBP generating an extended DNase I footprinting pattern ranging from position -19 to -42, These data suggest that the Pyrococcus homologue of TFIIB associates with the TBP-promoter binary complex as its eucaryal counterpart, but in contrast to eucaryal TFIIB, it causes an extension of the protection to the region upstream of the TATA box.