Cyclic di-GMP contributes to adaption and virulence of Bacillus thuringiensis through a riboswitch-regulated collagen adhesion protein.
Cyclic di-GMP contributes to adaption and virulence of Bacillus thuringiensis through a riboswitch-regulated collagen adhesion protein.
复制标题
环二 GMP 通过核糖开关调节的胶原粘附蛋白促进苏云金芽孢杆菌的适应和毒力
DOI：
10.1038/srep28807
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发表时间：
2016-07-06
影响因子：
4.6
通讯作者：
He J
中科院分区：
文献类型：
--
作者：
Tang Q;Yin K;Qian H;Zhao Y;Wang W;Chou SH;Fu Y;He J
环状双GMP是一种普遍存在的第二信使，通过与多种蛋白质或核糖开关效应器结合来调节细菌的多种细胞过程。在苏云金芽孢杆菌BMB171中，一个c-di-GMP核糖开关被称为Bc2 RNA，位于编码胶原黏附蛋白(Cap)的mRNA的5‘-非翻译区(5’-UTR)。在亲本菌株BMB171中，由于Bc2 RNA的存在，CAP的表达受到强烈抑制，而在Bc2 RNA无标记缺失突变体中，CaP的表达明显增强。BC2 RNA作为一个遗传的“开”开关，形成一个反终止子结构，促进c-di-GMP结合时的帽通读转录。结果，在高水平的c-di-GMP作用下，CAP转录被去抑制。因此，Bc2 RNA通过抑制/去抑制模型来调节CAP的表达。Bc2 RNA调控的Cap还与苏云金杆菌BMB171对其寄主棉铃虫的运动、聚集、胞外多糖分泌、生物膜形成和毒力密切相关。
Cyclic di-GMP is a ubiquitous second messenger that regulates diverse cellular processes in bacteria by binding to various protein or riboswitch effectors. In Bacillus thuringiensis BMB171, a c-di-GMP riboswitch termed Bc2 RNA resides in the 5′-untranslated region (5′-UTR) of an mRNA that encodes a collagen adhesion protein (Cap). The expression of cap was strongly repressed in parent strain BMB171 because of the presence of Bc2 RNA but was significantly promoted in the Bc2 RNA markerless deletion mutant. Bc2 RNA acts as a genetic “on” switch, which forms an anti-terminator structure to promote cap read-through transcription upon c-di-GMP binding. As a result, cap transcription was de-repressed under high c-di-GMP levels. Therefore, Bc2 RNA regulates cap expression using a repression/de-repression model. Bc2 RNA-regulated Cap was also found to be tightly associated with motility, aggregation, exopolysaccharide secretion, biofilm formation, and virulence of B. thuringiensis BMB171 against its host insect Helicoverpa armigera.