Bacteriophage-encoded transcription antiterminators play essential roles in the regulation of gene expression during infection. Here, we characterize the effects of the antiterminator protein P7 of bacteriophage Xp10 on transcriptional pausing by Xanthomonas oryzae RNA polymerase (RNAP) at different types of pause-inducing signals. When acting alone, P7 inhibits only hairpin-stabilized pauses, likely by preventing hairpin formation. In the presence of NusA, P7 also suppresses backtracking-stabilized pauses and the his elemental pause, but not the consensus elemental pause, suggesting that these pause signals may be mechanistically different. Thus, P7 and other bacteriophage proteins that bind near the RNA exit channel of RNAP have evolved to regulate transcription by suppressing RNAP pausing at a subset of regulatory signals, and to co-opt NusA in doing so.

中文翻译：

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噬菌体Xp10的抗终止蛋白P7通过细菌RNA聚合酶来区分不同类型的转录暂停。

噬菌体编码的转录抗终止剂在感染过程中的基因表达调节中起着重要作用。在这里，我们表征了噬菌体Xp10的抗终止子蛋白P7在不同类型的诱导停顿信号上对米色黄单胞菌RNA聚合酶（RNAP）的转录暂停的影响。当单独行动时，P7可能仅通过阻止发夹的形成而抑制发夹稳定的停顿。在存在NusA的情况下，P7还可以抑制回溯稳定的暂停和他的基本暂停，但不能抑制共有的基本暂停，这表明这些暂停信号可能在机理上有所不同。因此，在RNAP的RNA出口通道附近结合的P7和其他噬菌体蛋白已经进化为通过抑制一部分调节信号中的RNAP暂停来调节转录，