RNA polymerase-promoter interactions determining different stability of the Escherichia coli and Thermus aquaticus transcription initiation complexes.
RNA polymerase-promoter interactions determining different stability of the Escherichia coli and Thermus aquaticus transcription initiation complexes.
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RNA聚合酶促启动子的相互作用决定了大肠杆菌和热曲霉转录起始复合物的不同稳定性。
DOI：
10.1093/nar/gks973
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发表时间：
2012-12
影响因子：
14.9
通讯作者：
Severinov K
中科院分区：
文献类型：
--
作者：
Mekler V;Minakhin L;Kuznedelov K;Mukhamedyarov D;Severinov K
细菌RNA聚合酶(RNAP)形成的转录起始复合体在稳定性上因物种而异，从而导致不同的转录调控策略。这种多样性的分子基础尚不清楚。来自Thermus Aquaticus(Taq)的RNAP形成的启动子复合体比大肠杆菌RNAP启动子复合体稳定得多，特别是在低于37℃的温度下。在这里，我们使用荧光RNAP分子信标分析来识别部分RNAP与启动子的相互作用。我们定量比较了大肠杆菌和Taq RNAP与−10、−35和UP启动子元件、扩展的−10元件的TG基序、识别基因和下游双链启动子片段的部分相互作用强度。我们发现，与Taq RNAP相比，大肠杆菌RNAP只对上游元件和下游启动子双链具有更高的亲和力。这一结果表明，大肠杆菌和Taq启动子复合体之间的稳定性差异主要是由核心RNAP-DNA接触的差异强度决定的。我们认为，Taq RNAP与转录起点下游DNA的相互作用相对较弱是该酶形成的启动子复合体稳定性和温度敏感性较低的主要原因。
Transcription initiation complexes formed by bacterial RNA polymerases (RNAPs) exhibit dramatic species-specific differences in stability, leading to different strategies of transcription regulation. The molecular basis for this diversity is unclear. Promoter complexes formed by RNAP from Thermus aquaticus (Taq) are considerably less stable than Escherichia coli RNAP promoter complexes, particularly at temperatures below 37°C. Here, we used a fluorometric RNAP molecular beacon assay to discern partial RNAP-promoter interactions. We quantitatively compared the strength of E. coli and Taq RNAPs partial interactions with the −10, −35 and UP promoter elements; the TG motif of the extended −10 element; the discriminator and the downstream duplex promoter segments. We found that compared with Taq RNAP, E. coli RNAP has much higher affinity only to the UP element and the downstream promoter duplex. This result indicates that the difference in stability between E. coli and Taq promoter complexes is mainly determined by the differential strength of core RNAP–DNA contacts. We suggest that the relative weakness of Taq RNAP interactions with DNA downstream of the transcription start point is the major reason of low stability and temperature sensitivity of promoter complexes formed by this enzyme.
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影响因子：
64.5
作者：
Feklistov A;Darst SA
通讯作者：
Darst SA
影响因子：
16
作者：
Feklistov, Andrey;Barinova, Nataliya;Kulbachinskiy, Andrey
通讯作者：
Kulbachinskiy, Andrey
影响因子：
5.6
作者：
Bartlett, MS;Gaal, T;Gourse, RL
通讯作者：
Gourse, RL
影响因子：
4.8
作者：
Mekler, Vladimir;Minakhin, Leonid;Severinov, Konstantin
通讯作者：
Severinov, Konstantin
影响因子：
2.9
作者：
DEHASETH P L;LOHMAN T M;RECORD M T JR
通讯作者：
RECORD M T JR