Center of Life Sciences, Skolkovo Institute of Science and Technology, 121205 Moscow, Russia.
Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia.
Int J Mol Sci. 2022 Mar 26;23(7):3653. doi: 10.3390/ijms23073653.
6S RNA, a small non-coding RNA present in almost all bacteria, inhibits transcription via direct binding to RNA polymerase holoenzymes. The mechanism of 6S RNA action was investigated to a large extent in , however, lack of 6S RNA (Δ) was demonstrated to be unfavorable but not essential for cell survival under various growth conditions. In the present study, we revealed, for the first time, a lethal phenotype of the Δ strain in the presence of high concentrations of HO. This phenotype was rescued by complementation of the gene on a plasmid. We performed comparative qRT-PCR analyses on an enlarged set of mRNAs of genes associated with the oxidative stress response, allowing us to identify four genes known to be involved in this pathway (, , and ) that had decreased mRNA levels in the Δ strain. Finally, we performed comparative proteomic analyses of the wild-type and Δ strains, confirming that Δ bacteria have reduced levels of the proteins AhpC and Tpx involved in HO reduction. Our findings substantiate the crucial role of the riboregulator 6S RNA for bacterial coping with extreme stresses.
6S RNA 是一种存在于几乎所有细菌中的小非编码 RNA，通过直接结合 RNA 聚合酶全酶来抑制转录。然而，在 中，很大程度上研究了 6S RNA 的作用机制，缺乏 6S RNA（Δ）在各种生长条件下对细胞存活不利但不是必需的。在本研究中，我们首次揭示了在高浓度 HO 存在下Δ 菌株的致死表型。该表型可通过质粒上基因的互补来挽救。我们对与氧化应激反应相关的基因的 mRNA 进行了扩大的比较 qRT-PCR 分析，使我们能够鉴定出已知参与该途径的四个基因（、、和），它们在Δ 菌株中的 mRNA 水平降低。最后，我们对野生型和Δ 菌株进行了比较蛋白质组学分析，证实Δ 细菌中涉及 HO 还原的 AhpC 和 Tpx 蛋白水平降低。我们的发现证实了核糖调节因子 6S RNA 对细菌应对极端应激的至关重要的作用。
