Transcription factor E is a part of transcription elongation complexes
Transcription factor E is a part of transcription elongation complexes
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DOI：
10.1074/jbc.m707371200
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发表时间：
2007-12-07
影响因子：
4.8
通讯作者：
Thomm, Michael
中科院分区：
文献类型：
--
作者：
Grunberg, Sebastian;Bartlett, Michael S.;Thomm, Michael
一般真核转录因子TFE α亚基的n端结构域的同源物编码在所有测序的古菌基因组中，但古菌TFE在转录复合物中的位置尚未确定。我们发现TFE与单链DNA非特异性结合，光化学交联显示TFE与预先形成的开放转录泡结合。在起始前复合物中，TFE的n端包含一个带翼的螺旋-转-螺旋基序，在-9和-11位置特异性地与非模板DNA链的DNA交联。在+20位的配合物中，TFE特异性地与非模板链的+9、+11和+16位交联。对转录复合物+20位停滞的分析显示，tfe依赖于停滞RNA聚合酶恢复效率的增加，tfe诱导转录泡中胸腺嘧啶残基高锰酸盐敏感性的增强。这些结果证明了TFE在早期延伸复合物中的存在，并表明TFE在延伸期间稳定转录泡中的作用。
A homologue of the N-terminal domain of the alpha subunit of the general eukaryotic transcription factor TFE is encoded in the genomes of all sequenced archaea, but the position of archaeal TFE in transcription complexes has not yet been defined. We show here that TFE binds nonspecifically to single-stranded DNA, and photochemical cross-linking revealed TFE binding to a preformed open transcription bubble. In preinitiation complexes, the N-terminal part of TFE containing a winged helix-turn-helix motif is cross-linked specifically to DNA of the non-template DNA strand at positions -9 and -11. In complexes stalled at +20, TFE cross-linked specifically to positions +9, +11, and +16 of the non-template strand. Analyses of transcription complexes stalled at position +20 revealed a TFE-dependent increase of the resumption efficiency of stalled RNA polymerase and a TFE-induced enhanced permanganate sensitivity of thymine residues in the transcription bubble. These results demonstrate the presence of TFE in early elongation complexes and suggest a role of TFE in stabilization of the transcription bubble during elongation.