Global post-transcriptional regulators in P. aeruginosa

铜绿假单胞菌的全局转录后调节因子

基本信息

批准号：
10524023
负责人：
SIMON L DOVE
金额：
$ 57.91万
依托单位：
BOSTON CHILDREN'S HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-12-02 至 2024-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10524023
关键词：
Bacteria Base Pairing Binding Chronic Coupled DNA-Directed RNA Polymerase Enzymes Escherichia coli Family Free Ribosome Gene Expression Gene Expression Regulation Genes Genetic Transcription Gram-Negative Bacteria Infection Licensing Lung infections Mediating Messenger RNA Molecular Chaperones Morbidity - disease rate Nosocomial pneumonia Organism Orthologous Gene Patients Phenotype Prevention Pseudomonas aeruginosa Pseudomonas aeruginosa infection RNA RNA Degradation RNA-Binding Proteins Rho Factor Ribonucleases Sepsis Stretching Testing Transcript Translational Repression Translations Ventilator Virulence Work Wound Infection acute infection burn wound chronic infection cystic fibrosis patients experimental study human pathogen member mortality new therapeutic target opportunistic pathogen pathogenic bacteria posttranscriptional protein protein interaction recruit rho ribonuclease E transcription termination virulence gene

Bacteria Base Pairing Binding Chronic Coupled DNA-Directed RNA Polymerase Enzymes Escherichia coli Family Free Ribosome Gene Expression Gene Expression Regulation Genes Genetic Transcription Gram-Negative Bacteria Infection Licensing Lung infections Mediating Messenger RNA Molecular Chaperones Morbidity - disease rate Nosocomial pneumonia Organism Orthologous Gene Patients Phenotype Prevention Pseudomonas aeruginosa Pseudomonas aeruginosa infection RNA RNA Degradation RNA-Binding Proteins Rho Factor Ribonucleases Sepsis Stretching Testing Transcript Translational Repression Translations Ventilator Virulence Work Wound Infection acute infection burn wound chronic infection cystic fibrosis patients experimental study human pathogen member mortality new therapeutic target opportunistic pathogen pathogenic bacteria posttranscriptional protein protein interaction recruit rho ribonuclease E transcription termination virulence gene

展开

项目摘要

Abstract Pseudomonas aeruginosa is an important opportunistic pathogen of humans. It is the principal cause of morbidity and mortality in Cystic Fibrosis (CF) patients, a major cause of hospital-acquired pneumonia and is particulary problematic in burn wound infections. Hfq is a conserved global post-transcriptional regulator that is required for the virulence of P. aeruginosa. In other organisms Hfq is best known for its ability to promote the base-pairing between small regulatory RNAs (sRNAs) and their target transcripts. Hfq-promoted interaction between an sRNA and its mRNA target typically functions to repress translation of the target, although Hfq can also inhibit translation in an sRNA-independent fashion. We have found that in P. aeruginosa Hfq associates with hundreds of transcripts as they emerge from RNA polymerase. Because transcription and translation are coupled in bacteria, the interaction of Hfq with these nascent transcripts presumably allows this RNA-binding protein to exert its regulatory effects on translation at the earliest possible opportunity. In Aim 1 we propose to identify the targets of all the sRNAs that interact with Hfq in P. aeruginosa and determine whether these sRNAs frequently work in conjunction with Hfq on nascent transcripts. The interaction of Hfq with nascent transcripts has important implications for how transcript abundance can be controlled; specifically, Hfq- dependent inhibition of the translation of nascent transcripts would render them accessible to the transcription termination factor Rho or to ribonucleases. In Aim 1 we will determine whether Hfq reduces the abundance of those nascent transcripts it binds through effects on Rho-mediated transcription termination or through effects on RNA degradation. We have found that a second global post-transcriptional regulator in P. aeruginosa called RsmA also targets hundreds of nascent transcripts, including many of those that are targeted by Hfq. RsmA is a key regulator of the switch between acute and chronic infection phenotypes in P. aeruginosa and in Aim 2 we will investigate whether Hfq and RsmA modulate each other’s activities through competition or cooperation on common targets. Like Hfq, the binding of RsmA to target mRNA species typically inhibits their translation. In Aim 3 we propose to determine whether the interaction of RsmA with nascent transcripts influences their abundance through effects on Rho-mediated transcription termination or effects on RNA degradation. The experiments outlined in this proposal are expected to illuminate how Hfq and RsmA control gene expression through their widespread targeting of nascent transcripts. The co-transcriptional activities of these global post- transcriptional regulators have been underexplored and our proposed studies may have implications not only for how Hfq and RsmA impact the virulence of P. aeruginosa, but also for how their orthologs influence virulence gene expression in other pathogenic bacteria that contain them.

抽象的铜绿假单胞菌是人类的重要机会病原体。这是囊性纤维化（CF）患者的发病率和死亡率，这是医院获得性肺炎的主要原因，IS 在烧伤伤口感染中特别有问题。 HFQ是一个配置的全局转录后调节器，是铜绿假单胞菌病毒所必需的。在其他生物体中，HFQ以促进它的能力而闻名小调节性RNA（SRNA）及其目标转录本之间的基础配对。 HFQ促进的相互作用在SRNA及其mRNA靶标之间通常可以反映目标的翻译，尽管HFQ可以还以独立于SRNA的方式抑制翻译。我们发现在铜绿假单胞菌HFQ Associates中从RNA聚合酶出来时，有数百个转录本。因为转录和翻译是耦合在细菌中，HFQ与这些新生的转录本的相互作用大概可以使这种RNA结合蛋白质以最早可能的机会对翻译执行调节作用。在目标1中，我们建议确定所有与铜绿假单胞菌中与HFQ相互作用的SRNA的靶标 SRNA经常与HFQ一起在新生的转录本上使用。 HFQ与新生的相互作用成绩单对如何控制转录本丰度具有重要意义。具体而言，HFQ- 对新生转录本的翻译的依赖性抑制作用将使它们可访问转录终止因子Rho或丝带酶。在AIM 1中，我们将确定HFQ是否减少那些新生的转录本通过对Rho介导的转录终止的影响或通过影响而结合关于RNA降解。我们发现，铜绿假单胞菌中的第二个全球转录后调节器称为 RSMA还针对数百个新生的转录本，包括许多由HFQ靶向的。 RSMA是铜绿假单胞菌和AIM 2中急性和慢性感染表型之间切换的关键调节器将调查HFQ和RSMA是否通过竞争或合作来调节彼此的活动常见目标。像HFQ一样，RSMA对靶向mRNA物种的结合通常会抑制其翻译。在目的3我们建议确定RSMA与新生转录本的相互作用是否影响其通过对Rho介导的转录终止的影响或对RNA降解的影响的抽象。这预计该提案中概述的实验将阐明HFQ和RSMA控制基因表达如何通过其宽度靶向新生的转录本。这些全球后的共同交易活动 - 转录调节剂没有被逐渐解散，我们提出的研究不仅具有影响关于HFQ和RSMA如何影响铜绿假单胞菌的病毒，以及它们的直系同源物如何影响含有它们的其他致病细菌中的毒力基因表达。