Department of Life Science, Chung-Ang University, Seoul, 06974, Republic of Korea.
Department of Microbiology, College of Medicine, Hallym University, Chuncheon, 24252, Republic of Korea.
J Microbiol. 2021 Dec;59(12):1133-1141. doi: 10.1007/s12275-021-1518-5. Epub 2021 Nov 9.
RraA, a protein regulator of RNase E activity, plays a unique role in modulating the mRNA abundance in Escherichia coli. The marine pathogenic bacterium Vibrio vulnificus also possesses homologs of RNase E (VvRNase E) and RraA (VvRraA1 and VvRraA2). However, their physiological roles have not yet been investigated. In this study, we demonstrated that VvRraA1 expression levels affect the pathogenicity of V. vulnificus. Compared to the wild-type strain, the VvrraA1-deleted strain (ΔVvrraA1) showed decreased motility, invasiveness, biofilm formation ability as well as virulence in mice; these phenotypic changes of ΔVvrraA1 were restored by the exogenous expression of VvrraA1. Transcriptomic analysis indicated that VvRraA1 expression levels affect the abundance of a large number of mRNA species. Among them, the half-lives of mRNA species encoding virulence factors (e.g., smcR and htpG) that have been previously shown to affect VvrraA1 expression-dependent phenotypes were positively correlated with VvrraA1 expression levels. These findings suggest that VvRraA1 modulates the pathogenicity of V. vulnificus by regulating the abundance of a subset of mRNA species.
RraA 是一种调节 RNase E 活性的蛋白质调节剂，在调节大肠杆菌中 mRNA 丰度方面发挥着独特的作用。海洋致病性细菌创伤弧菌也具有 RNase E（VvRNase E）和 RraA（VvRraA1 和 VvRraA2）的同源物。然而，它们的生理作用尚未被研究。在本研究中，我们证明了 VvRraA1 的表达水平影响创伤弧菌的致病性。与野生型菌株相比，VvrraA1 缺失菌株（ΔVvrraA1）的运动性、侵袭性、生物膜形成能力和在小鼠中的毒力降低；这些ΔVvrraA1 的表型变化通过外源性表达 VvrraA1 得到恢复。转录组分析表明，VvRraA1 的表达水平影响大量 mRNA 种类的丰度。其中，先前已经表明影响 VvrraA1 表达依赖性表型的毒力因子（例如 smcR 和 htpG）的 mRNA 种类的半衰期与 VvrraA1 的表达水平呈正相关。这些发现表明，VvRraA1 通过调节一组 mRNA 种类的丰度来调节创伤弧菌的致病性。
