The Role of tmRNA in development of C. crescentus

tmRNA 在 C. crescentus 发育中的作用

基本信息

批准号：
8478129
负责人：
KENNETH C KEILER
金额：
$ 23.94万
依托单位：
PENNSYLVANIA STATE UNIVERSITY, THE
依托单位国家：
美国
项目类别：
财政年份：
2004
资助国家：
美国
起止时间：
2004-05-01 至 2015-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8478129
关键词：
Anti-Bacterial Agents Antibiotics Bacteria Bacterial Physiology Binding Biochemical Biological Assay Biological Models C-terminal Caulobacter crescentus Cell Cycle Cell Cycle Progression Cell Cycle Regulation Cells Complex Cues DNA Replication Timing DNA-Directed RNA Polymerase Data Defect Development Environment Escherichia coli Gene Expression Gene Expression Regulation Generations Genetic Goals Growth and Development function In Vitro Investigation Knowledge Learning Medical Messenger RNA Molecular Molecular Profiling Nucleic Acids Pathogenesis Pathway interactions Peptide Hydrolases Pharmaceutical Preparations Phenotype Physiological Physiological Processes Physiology Post-Transcriptional Regulation Process Protein Translation Pathway Proteins Proteolysis Reaction Regulation Replication Initiation Research Ribonucleoproteins Ribosomes Role Shigella flexneri Signal Transduction System Terminator Codon Testing Time Trans-Activators Translations Virulence Work base biological adaptation to stress design in vivo inhibitor/antagonist mutant novel particle pathogenic bacteria polypeptide prevent research study response ribonuclease R tmRNA

项目摘要

DESCRIPTION (provided by applicant): Bacteria lacking trans-translation activity have defects in development, differentiation, virulence, stress responses, and viability, but the reasons trans-translation is required for these processes are not known. Our long-term goal is to understand the mechanism of action and physiological role of trans-translation in bacteria. The overall objective of this application is to understand how regulation of trans-translation activity and substrate selectivity is used to control genetic pathways responsible for differentiation and cell cycle progression in Caulobacter crescentus. Our central hypothesis is that bacteria regulate the generation of key substrates for trans-translation, as well as the availability of tmRNA and SmpB, to control genetic circuits responsible for initiation of DNA replication and other physiological processes. The rationale for the proposed research is to establish a paradigm for post-transcriptional regulation through controlled trans-translation. The central hypothesis will be tested by pursuing the following specific aims: 1) identify the mechanism for generation of trans-translation substrates in C. crescentus; 2) identify mechanisms for regulation of trans- translation activity; and 3) determine the role of trans-translation in co-translational secretion. Under the first aim, genetic and biochemical approaches will be used to identify cis- and trans-acting factors responsible for substrate selectivity through a nucleic acid motif found in 66% of trans-translation substrates. In the second aim, genetic and biochemical assays will be used to identify the molecular interactions responsible for cell- cycle regulated SmpB proteolysis and tmRNA degradation by RNase R. In the third aim, the molecular basis for the genetic interaction between trans-translation and the SecYEG translocator will be tested. The proposed research is significant because it will provide a paradigm for post-transcriptional gene regulation by trans- translation that is required for bacterial growth and development. This paradigm will open the door to a more detailed understanding of how bacteria rapidly change their gene expression profiles in response to environmental and developmental cues. Elucidation of this process in a model system for bacterial development is expected to provide a framework for interpreting a wide array of data from other species, and a basis for understanding how trans-translation is used by bacteria in the environment and during pathogenesis.

描述（由申请人提供）：缺乏跨翻译活性的细菌在发育，分化，毒力，压力反应和生存力方面存在缺陷，但是这些过程需要跨翻译的原因。我们的长期目标是了解跨翻译在细菌中的作用机理和生理作用。该应用的总体目的是了解跨翻译活性和底物选择性的调节如何用于控制负责分化和细胞周期进程的遗传途径。我们的中心假设是，细菌调节了跨翻译的关键底物以及TMRNA和SMPB的可用性，以控制负责启动DNA复制和其他生理过程的遗传回路。拟议的研究的理由是通过受控的跨翻译建立用于转录后调节的范例。中心假设将通过追求以下特定目的进行检验：1）确定在C. crescentus中产生跨翻译底物的机制； 2）确定调节转换活性的机制； 3）确定跨翻译在共同分泌中的作用。在第一个目标下，将使用遗传和生化方法来识别通过在66％的反式翻译底物中发现的核酸基序来确定底物选择性的顺式和反式作用因子。在第二个目标中，遗传和生化测定将用于确定RNaseR的细胞周期调节SMPB蛋白水解和TMRNA降解的分子相互作用。将测试Secyeg转运器。拟议的研究之所以重要，是因为它将通过细菌生长和发育所必需的转移来为转录后基因调节提供范式。这种范式将为对环境和发育线索的响应如何迅速改变其基因表达谱迅速改变其基因表达谱。预计在细菌开发模型系统中阐明该过程将为解释其他物种的广泛数据提供一个框架，以及了解细菌在环境中和发病机理中如何使用跨翻译的基础。