Direct interaction of small non-coding RNAs CjNC140 and CjNC110 optimizes expression of key pathogenic phenotypes of Campylobacter jejuni.
Direct interaction of small non-coding RNAs CjNC140 and CjNC110 optimizes expression of key pathogenic phenotypes of Campylobacter jejuni.
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小的非编码RNA（sRNA）是调节细菌病原体中基因表达的重要参与者，但它们在空肠弯曲菌（人类食源性胃肠炎的重要原因）中的功能在很大程度上是不确定的。在本研究中，我们阐明了sRNA CjNC 140的功能及其与CjNC 110的相互作用，CjNC 110是一种先前表征的sRNA，参与了几种毒力表型的调控。空肠。灭活CjNC 140增加运动性，自凝集，L-甲硫氨酸浓度，autoinducer-2生产，过氧化氢抗性，和早期鸡定植，表明CjNC 140对这些表型的主要抑制作用。除了运动性之外，所有这些作用都与先前证明的CjNC 110的正调节形成直接对比，表明CjNC 110和CjNC 140以相反的方式调节C.空肠。RNAseq和北方印迹进一步证明，在不存在CjNC 110的情况下，CjNC 140的表达增加，而在不存在CjNC 140的情况下，CjNC 110的表达降低，这表明它们直接相互作用的可能性。实际上，电泳迁移率变动测定证明了两种sRNA之间经由富含GA-（CjNC 110）和CU-（CjNC 140）的茎环的直接结合。此外，RNAseq和后续实验确定了CjNC 140正调控p19，p19编码弯曲杆菌中的关键铁摄取转运蛋白。此外，计算分析显示CjNC 140和CjNC 110在C.空肠，和预测的二级结构支持CjNC 140作为铁调节sRNA，RyhB的功能同源物。这些发现确立了CjNC 140和CjNC 110作为维持基因表达稳态和优化C.空肠病理生物学基因调控对细菌疾病发病机制的各个方面都至关重要，而小的非编码RNA（sRNA）代表了细菌基因调控的新前沿。在空肠弯曲菌中，sRNA的作用仍然在很大程度上未被探索。在这里，我们研究了两个高度保守的sRNA，CjNC 110和CjNC 140的作用，并证明，CjNC 140显示了主要的抑制作用，相反，主要激活作用CjNC 110的几个关键的毒力相关的表型。我们的研究结果还表明，sRNA调控途径与铁摄取系统交织在一起，铁摄取系统是体内定植的另一个关键毒力机制。这些发现为理解C.空肠的病理生物学，并确定潜在的目标，为干预这一主要的食源性病原体。
Small non-coding RNAs (sRNAs) are important players in modulating gene expression in bacterial pathogens, but their functions are largely undetermined in Campylobacter jejuni, an important cause of foodborne gastroenteritis in humans. In this study, we elucidated the functions of sRNA CjNC140 and its interaction with CjNC110, a previously characterized sRNA involved in the regulation of several virulence phenotypes of C. jejuni. Inactivation of CjNC140 increased motility, autoagglutination, L-methionine concentration, autoinducer-2 production, hydrogen peroxide resistance, and early chicken colonization, indicating a primarily inhibitory role of CjNC140 for these phenotypes. Apart from motility, all these effects directly contrasted the previously demonstrated positive regulation by CjNC110, suggesting that CjNC110 and CjNC140 operate in an opposite manner to modulate physiologic processes in C. jejuni. RNAseq and northern blotting further demonstrated that expression of CjNC140 increased in the absence of CjNC110, while expression of CjNC110 decreased in the absence of CjNC140, suggesting a possibility of their direct interaction. Indeed, electrophoretic mobility shift assay demonstrated a direct binding between the two sRNAs via GA- (CjNC110) and CU- (CjNC140) rich stem-loops. Additionally, RNAseq and follow-up experiments identified that CjNC140 positively regulates p19, which encodes a key iron uptake transporter in Campylobacter. Furthermore, computational analysis revealed both CjNC140 and CjNC110 are highly conserved in C. jejuni, and the predicted secondary structures support CjNC140 as a functional homolog of the iron regulatory sRNA, RyhB. These findings establish CjNC140 and CjNC110 as a key checks-and- balances mechanism in maintaining homeostasis of gene expression and optimizing phenotypes critical for C. jejuni pathobiology. Gene regulation is critical to all aspects of pathogenesis of bacterial disease, and small non-coding RNAs (sRNAs) represent a new frontier in gene regulation of bacteria. In Campylobacter jejuni, the role of sRNAs remains largely unexplored. Here, we investigate the role of two highly conserved sRNAs, CjNC110 and CjNC140, and demonstrate that CjNC140 displays a primarily inhibitory role in contrast to a primarily activating role for CjNC110 for several key virulence-associated phenotypes. Our results also revealed that the sRNA regulatory pathway is intertwined with the iron uptake system, another virulence mechanism critical for in vivo colonization. These findings open a new direction for understanding C. jejuni pathobiology and identify potential targets for intervention for this major foodborne pathogen.
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影响因子：
1
作者：
Burrough, Eric R.;Sahin, Orhan;Yaeger, Michael J.
通讯作者：
Yaeger, Michael J.
影响因子：
11.3
作者：
Beisel CL;Storz G
通讯作者：
Storz G
影响因子：
3.7
作者：
通讯作者：
--
DOI：
10.1099/mic.0.050278-0
发表时间：
2011-10
期刊：
Microbiology (Reading, England)
影响因子：
--
作者：
Chaudhuri RR;Yu L;Kanji A;Perkins TT;Gardner PP;Choudhary J;Maskell DJ;Grant AJ
通讯作者：
Grant AJ
影响因子：
2.2
作者：
Chen, CY;Nace, GW;Irwin, PL
通讯作者：
Irwin, PL