State Key Laboratory of Oral Diseases, Department of Preventive Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China.
Department of Endodontics, College of Stomatology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
J Dent Res. 2020 Feb;99(2):204-213. doi: 10.1177/0022034519890570. Epub 2019 Dec 10.
is a major cariogenic pathogen that resides in multispecies oral microbial biofilms. The VicRK 2-component system is crucial for bacterial adaptation, virulence, and biofilm organization and contains a global and vital response regulator, VicR. Notably, we identified an antisense RNA (AS) associated with an adjacent RNase III-encoding () gene that was relevant to microRNA-size small RNAs (msRNAs). Here, we report that ASvicR overexpression significantly impeded bacterial growth, biofilm exopolysaccharide synthesis, and cariogenicity in vivo. Transcriptome analysis revealed that the AS RNA mainly regulated carbohydrate metabolism. In particular, overproducing AS demonstrated a reduction in galactose and glucose metabolism by monosaccharide composition analysis. The results of high-performance gel permeation chromatography revealed that the water-insoluble glucans isolated from AS presented much lower molecular weights. Furthermore, direct evidence showed that total RNAs were disrupted by -encoded RNase III. With the coexpression of T4 RNA ligase, putative msRNA1657, which is an -related messenger RNA, was verified to bind to the 5'-UTR regions of the gene. Furthermore, AS regulation revealed a sponge regulatory-mediated network for msRNA associated with adjacent RNase III-encoding genes. There was an increase in AS transcript levels in clinical strains from caries-free children, while the expression of AS was decreased in early childhood caries patients; this outcome may be explored as a potential strategy contributing to the management of dental caries. Taken together, our findings suggest an important role of AS-mediated sponge regulation in , indicating the characterization of lactose metabolism by a vital response regulator in cariogenicity. These findings have a number of implications and have reshaped our understanding of bacterial gene regulation from its transcriptional conception to the key roles of regulatory RNAs.
是一种主要的致龋病原体，存在于多物种口腔微生物生物膜中。VicRK 双组分系统对于细菌的适应、毒力和生物膜组织至关重要，其中包含一个全局和重要的响应调节剂 VicR。值得注意的是，我们鉴定出一种与相邻的 RNase III 编码基因相关的反义 RNA（AS），该基因与 microRNA 大小的小 RNA（msRNA）有关。在这里，我们报告 ASvicR 的过表达显着阻碍了细菌的生长、生物膜胞外多糖的合成和体内致龋性。转录组分析表明，AS RNA 主要调节碳水化合物代谢。特别是，通过单糖组成分析，过表达 AS 显示出半乳糖和葡萄糖代谢的减少。高效凝胶渗透色谱的结果表明，从 AS 分离出的不溶性葡聚糖具有更低的分子量。此外，直接证据表明 - 编码的 RNase III 破坏了总 RNA。随着 T4 RNA 连接酶的共表达，假定的 msRNA1657，它是一种与相关的信使 RNA，被验证与基因的 5'-UTR 区域结合。此外，AS 调节揭示了与相邻 RNase III 编码基因相关的 msRNA 调节的海绵样网络。从无龋儿童的临床菌株中观察到 AS 转录本水平增加，而在儿童早期龋患者中 AS 的表达减少；这一结果可能被探索为管理龋齿的潜在策略。总之，我们的研究结果表明 AS 介导的海绵调节在中的重要作用，表明乳糖代谢由致龋性中的重要响应调节剂来调节。这些发现具有重要意义，并从转录概念到调节 RNA 的关键作用重新塑造了我们对细菌基因调控的理解。
