RNA polymerase mutations that facilitate replication progression in the rep uvrD recF mutant lacking two accessory replicative helicases.
RNA polymerase mutations that facilitate replication progression in the rep uvrD recF mutant lacking two accessory replicative helicases.
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DOI：
10.1111/j.1365-2958.2010.07208.x
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发表时间：
2010-07
影响因子：
3.6
通讯作者：
Michel B
中科院分区：
文献类型：
--
作者：
Baharoglu Z;Lestini R;Duigou S;Michel B
我们观察到，缺乏Rep和UvrD这两种复制辅助解旋酶的细胞以及重组蛋白recf在富营养液中是低温敏感的。我们分离了五个抑制Luria-Bertani(LB)低温敏感性的突变，并表明它们映射在编码RNA聚合酶RpoB和RpoC亚单位的基因中。对这些rpoB突变体(D444G、H447R和N518D)和rpoC突变体(H113R和P451L)进行了鉴定。RpoBH447R和rpoBD444G阻止Prrn核心启动子在富含介质中的激活，但只有rpoBH447R还抑制相关点突变体(严格样表型)的营养缺陷症。RpoCH113R抑制grea greb突变体的温度敏感性，表明它破坏了停滞的伸长复合体的稳定。除rpoCP451L外，所有突变均可阻止R-环的形成。我们认为，这些rpo突变允许在没有Rep和UvrD的情况下进行复制，方法是在复制-转录碰撞时破坏RNA Pol的稳定。在recf+的背景下，只有当Ding存在时，它们才能促进Rep UvrD细胞的生长，支持Rep、UvrD和Ding促进复制叉在转录序列中的进展的假设。它们拯救了rep UvrD Ding recf细胞，表明在recf突变体中，被不稳定转录复合体阻止的复制叉子可以在没有Rep、UvrD和Ding三个已知复制辅助螺旋酶的情况下重新启动。
We observed that cells lacking Rep and UvrD, two replication accessory helicases, and the recombination protein RecF are cryo-sensitive on rich medium. We isolated five mutations that suppress this Luria–Bertani (LB)-cryo-sensitivity and show that they map in the genes encoding the RNA polymerase subunits RpoB and RpoC. These rpoB (D444G, H447R and N518D) and rpoC mutants (H113R and P451L) were characterized. rpoBH447R and rpoBD444G prevent activation of the Prrn core promoter in rich medium, but only rpoBH447R also suppresses the auxotrophy of a relA spoT mutant (stringent-like phenotype). rpoCH113R suppresses the thermo-sensitivity of a greA greB mutant, suggesting that it destabilizes stalled elongation complexes. All mutations but rpoCP451L prevent R-loop formation. We propose that these rpo mutations allow replication in the absence of Rep and UvrD by destabilizing RNA Pol upon replication–transcription collisions. In a RecF+ context, they improve growth of rep uvrD cells only if DinG is present, supporting the hypothesis that Rep, UvrD and DinG facilitate progression of the replication fork across transcribed sequences. They rescue rep uvrD dinG recF cells, indicating that in a recF mutant replication forks arrested by unstable transcription complexes can restart without any of the three known replication accessory helicases Rep, UvrD and DinG.
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影响因子：
16.6
作者：
Nudler E
通讯作者：
Nudler E
影响因子：
16
作者：
Guy, Colin P.;Atkinson, John;Gupta, Milind K.;Mahdi, Akeel A.;Gwynn, Emma J.;Rudolph, Christian J.;Moon, Peter B.;van Knippenberg, Ingeborg C.;Cadman, Chris J.;Dillingham, Mark S.;Lloyd, Robert G.;McGlynn, Peter
通讯作者：
McGlynn, Peter
DOI：
10.1073/pnas.0501170102
发表时间：
2005-05-31
影响因子：
11.1
作者：
Paul, BJ;Berkmen, MB;Gourse, RL
通讯作者：
Gourse, RL
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：
Szalewska-Palasz, Agnieszka;Johansson, Linda U. M.;Shingler, Victoria
通讯作者：
Shingler, Victoria