The hydrogen peroxide-induced small RNA OxyS has been proposed to originate from the 3′ UTR of a peroxide mRNA. Unexpectedly, phylogenetic OxyS targetome predictions indicate that most OxyS targets belong to the category of “cell cycle,” including cell division and cell elongation. Previously, we reported that Escherichia coli OxyS inhibits cell division by repressing expression of the essential transcription termination factor nusG, thereby leading to the expression of the KilR protein, which interferes with the function of the major cell division protein, FtsZ. By interfering with cell division, OxyS brings about cell-cycle arrest, thus allowing DNA damage repair. Cell division and cell elongation are opposing functions to the extent that inhibition of cell division requires a parallel inhibition of cell elongation for the cells to survive. In this study, we report that in addition to cell division, OxyS inhibits mepS, which encodes an essential peptidoglycan endopeptidase that is responsible for cell elongation. Our study indicates that cell-cycle arrest and balancing between cell division and cell elongation are important and conserved functions of the oxidative stress-induced sRNA OxyS.

中文翻译：

---

OxyS RNA 中两个不同的调控位点确保细胞分裂的平衡


过氧化氢诱导的小 RNA OxyS 被认为源自过氧化物 mRNA 的 3' UTR。出乎意料的是，系统发育OxyS靶标组预测表明大多数OxyS靶标属于“细胞周期”类别，包括细胞分裂和细胞伸长。此前，我们报道了大肠杆菌OxyS通过抑制必需转录终止因子nusG的表达来抑制细胞分裂，从而导致KilR蛋白的表达，从而干扰主要细胞分裂蛋白FtsZ的功能。通过干扰细胞分裂，OxyS 导致细胞周期停滞，从而实现 DNA 损伤修复。细胞分裂和细胞伸长是相反的功能，抑制细胞分裂需要同时抑制细胞伸长才能使细胞存活。在这项研究中，我们报告说，除了细胞分裂之外，OxyS 还能抑制mepS ，mepS 编码一种负责细胞伸长的必需肽聚糖内肽酶。我们的研究表明，细胞周期停滞以及细胞分裂和细胞伸长之间的平衡是氧化应激诱导的 sRNA OxyS 的重要且保守的功能。