The RNA Domain Vc1 Regulates Downstream Gene Expression in Response to Cyclic Diguanylate in Vibrio cholerae.
The RNA Domain Vc1 Regulates Downstream Gene Expression in Response to Cyclic Diguanylate in Vibrio cholerae.
复制标题
DOI：
10.1371/journal.pone.0148478
复制
发表时间：
2016
期刊：
影响因子：
3.7
通讯作者：
Tamayo R
中科院分区：
文献类型：
--
作者：
Kariisa AT;Weeks K;Tamayo R
在许多细菌物种中，包括水生细菌和人类病原体霍乱弧菌，第二信使环二鸟苷酸（c-di-GMP）调节生物膜形成，运动性和毒力因子产生等过程。通过与各种效应物相互作用，c-di-GMP调节基因表达或蛋白质功能。一种类型的c-di-GMP受体是I类核糖开关，其代表已显示在体外结合c-di-GMP。在此，我们研究了霍乱弧菌中推定的I类核糖开关Vc 1的体外和体内功能，Vc 1位于编码GbpA的基因的上游，GbpA是一种定植因子，有助于霍乱弧菌附着于含有N-乙酰葡糖胺部分的环境和宿主表面。我们提供的证据表明，VC 1 RNA直接与c-di-GMP在体外相互作用，这类核糖开关之间保守的核苷酸是重要的结合。然而，霍乱弧菌染色体中这些保守残基的突变单独地不一致地影响gbpA的表达和GbpA蛋白的产生。通过分离VC 1的调节功能，我们发现VC 1元件积极调节下游基因表达，以响应c-di-GMP。总之，这些数据表明，Vc 1元件响应于c-di-GMP在体内。c-di-GMP通过Vc 1对gbpA表达的正向调节可能影响霍乱弧菌在水环境和宿主肠道环境中与几丁质结合的能力。
In many bacterial species, including the aquatic bacterium and human pathogen Vibrio cholerae, the second messenger cyclic diguanylate (c-di-GMP) modulates processes such as biofilm formation, motility, and virulence factor production. By interacting with various effectors, c-di-GMP regulates gene expression or protein function. One type of c-di-GMP receptor is the class I riboswitch, representatives of which have been shown to bind c-di-GMP in vitro. Herein, we examined the in vitro and in vivo function of the putative class I riboswitch in Vibrio cholerae, Vc1, which lies upstream of the gene encoding GbpA, a colonization factor that contributes to attachment of V. cholerae to environmental and host surfaces containing N-acetylglucosamine moieties. We provide evidence that Vc1 RNA interacts directly with c-di-GMP in vitro, and that nucleotides conserved among this class of riboswitch are important for binding. Yet the mutation of these conserved residues individually in the V. cholerae chromosome inconsistently affects the expression of gbpA and production of the GbpA protein. By isolating the regulatory function of Vc1, we show that the Vc1 element positively regulates downstream gene expression in response to c-di-GMP. Together these data suggest that the Vc1 element responds to c-di-GMP in vivo. Positive regulation of gbpA expression by c-di-GMP via Vc1 may influence the ability of V. cholerae to associate with chitin in the aquatic environment and the host intestinal environment.