The largest and best studied group of regulatory small RNAs (sRNAs) in bacteria act by modulating translation or turnover of messenger RNAs (mRNAs) through base-pairing interactions that typically take place near the 5' end of the mRNA. This allows the sRNA to bind the complementary target sequence while the remainder of the mRNA is still being made, creating conditions whereby the action of the sRNA can extend to transcriptional steps, most notably transcription termination. Increasing evidence corroborates the existence of a functional interplay between sRNAs and termination factor Rho. Two general mechanisms have emerged. One mechanism operates in translated regions subjected to sRNA repression. By inhibiting ribosome binding co-transcriptionally, the sRNA uncouples translation from transcription, allowing Rho to bind the nascent RNA and promote termination. In the second mechanism, which functions in 5' untranslated regions, the sRNA antagonizes termination directly by interfering with Rho binding to the RNA or the subsequent translocation along the RNA. Here, we review the above literature in the context of other mechanisms that underlie the participation of Rho-dependent transcription termination in gene regulation. This article is part of a Special Issue entitled: RNA and gene control in bacteria edited by Dr. M. Guillier and F. Repoila.

中文翻译：

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小RNA和转录终止因子Rho之间的调节相互作用。

细菌中调节性小RNA（sRNA）的数量最多，研究最好，其作用是通过通常在mRNA的5'端附近发生的碱基配对相互作用来调节信使RNA（mRNA）的翻译或转换。这使得sRNA可以与互补靶序列结合，而其余的mRNA仍在制造中，从而创造了条件，使sRNA的作用可以延伸至转录步骤，尤其是转录终止。越来越多的证据证实了sRNA与终止因子Rho之间存在功能相互作用。出现了两种一般机制。一种机制在经受sRNA抑制的翻译区域中起作用。sRNA通过共转录抑制核糖体结合，使翻译与转录解偶联，允许Rho结合新生的RNA并促进终止。在作用于5'非翻译区的第二种机制中，sRNA通过干扰Rho与RNA的结合或随后沿RNA的易位而直接拮抗终止。在这里，我们在其他机制的背景下审查上述文献，这些机制是Rho依赖性转录终止参与基因调控的基础。本文是M. Guillier博士和F. Repoila编辑的《细菌中的RNA和基因控制》特刊的一部分。我们在基础Rho依赖转录终止参与基因调控的其他机制的背景下审查了上述文献。本文是M. Guillier博士和F. Repoila编辑的《细菌中的RNA和基因控制》特刊的一部分。我们在基础Rho依赖转录终止参与基因调控的其他机制的背景下审查了上述文献。本文是M. Guillier博士和F. Repoila编辑的《细菌中的RNA和基因控制》特刊的一部分。