Molecular mechanisms of gene regulation in Chlamydia

衣原体基因调控的分子机制

• 批准号: 7017102
• 负责人: Ming Tan
• 金额: $ 9.48万
• 依托单位: UNIVERSITY OF CALIFORNIA-IRVINE
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-02-01 至 2009-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7017102
• 关键词: Chlamydia trachomatis; Chlamydiaceae; DNA directed RNA polymerase; bacterial cytopathogenic effect; bacterial genetics; bacterial proteins; bioinformatics; computer system design /evaluation; gene expression; genetic regulation; genetic regulatory element; genetic transcription; heat shock proteins; nucleic acid sequence; protein protein interaction; recombinant proteins; temperature; Chlamydia trachomatis; Chlamydiaceae; DNA directed RNA polymerase; bacterial cytopathogenic effect; bacterial genetics; bacterial proteins; bioinformatics; computer system design /evaluation; gene expression; genetic regulation; genetic regulatory element; genetic transcription; heat shock proteins; nucleic acid sequence; protein protein interaction; recombinant proteins; temperature

DESCRIPTION (provided by applicant): Dr. Ming Tan is a physician scientist with a research interest in bacterial pathogenesis and infectious diseases. He is a faculty member in the Department of Microbiology and Molecular Genetics at the University of California, Irvine, which has a strong record of research in microbial pathogenesis and gene regulation. Dr. Tan is studying the bacterial pathogen, Chlamydia, which is the leading cause of sexually transmitted disease in the developed world and one of the main causes of preventable blindness in the developing world. In addition, Chlamydia has been associated with atherosclerotic heart disease. Dr. Tan's career goal is to maintain an independent research program that ultimately leads to new insights into chlamydial pathogenesis, and new therapeutic and preventative approaches towards chlamydial infections. Dr. Tan is investigating the intracellular survival and replication of Chlamydia, with a focus on the molecular mechanisms of chlamydial gene regulation. He is using an in vitro approach to study gene regulation, based on the transcription of cloned chlamydial promoters by purified RNA polymerase. In this proposal, several different mechanisms that regulate promoter activity will be investigated. A cis-acting DNA element has been identified in many chlamydial promoters and its presence increases promoter activity. Dr. Tan hypothesizes that a putative activator binds to this DNA element and upregulates transcription, providing a general switch for turning on chlamydial gene expression. This hypothesis will be tested by determining if the activity that is dependent on the DNA element is separable from the activity of RNA polymerase. Dr. Tan has also demonstrated that regulated chlamydial transcription can be reconstituted by adding recombinant chlamydial proteins to his in vitro assay. For example, heat shock promoters have been shown to be regulated by a transcriptional repressor. The mechanism by which increased temperature modulates the activity of this repressor, and leads to upregulation of heat shock gene expression, will be examined in this proposal. Additional forms of regulation will be studied by testing the activity of candidate transcription factors. Dr. Tan has reconstituted the activity of an alternative chlamydial RNA polymerase that transcribes specific genes by recognizing a different promoter structure. This reconstituted activity will be combined with a bioinformatics approach to identify genes that are regulated by this alternative RNA polymerase.

描述（由申请人提供）：Ming Tan博士是一名医生科学家，对细菌发病机理和传染病具有研究兴趣。他是加利福尼亚大学尔湾分校微生物和分子遗传学系的教职员工，该学位在微生物发病机理和基因调节方面具有很强的研究记录。 Tan博士正在研究细菌病原体衣原体，这是发达国家性传播疾病的主要原因，也是发展中国家可预防失明的主要原因之一。此外，衣原体与动脉粥样硬化心脏病有关。 Tan博士的职业目标是维护一项独立的研究计划，最终导致对衣原体发病机理的新见解，以及针对衣原体感染的新治疗和预防方法。 Tan博士正在研究衣原体的细胞内存活和复制，重点是衣原体基因调节的分子机制。他正在使用一种基于纯化的RNA聚合酶克隆的衣原体启动子的转录来研究基因调节。在此提案中，将研究几种调节启动子活性的不同机制。在许多衣原体启动子中已经鉴定出顺式作用DNA元件，其存在会增加启动子活性。 TAN博士假设假定的激活剂与该DNA元件结合并上调转录，从而提供了一个通用开关，用于打开衣原体基因表达。该假设将通过确定取决于DNA元素的活性是否与RNA聚合酶活性分离来检验。 Tan博士还证明，可以通过在其体外测定中添加重组衣原体蛋白来重构受调节的衣原体转录。例如，热激启动子已显示由转录阻遏物调节。该提案将检查温度升高调节该阻遏物活性并导致热休克表达的上调的机制。通过测试候选转录因子的活性，将研究其他形式的调节。 Tan博士重构了替代性衣原体RNA聚合酶的活性，该衣原体RNA聚合酶通过识别不同的启动子结构来转录特定基因。这种重构活性将与生物信息学方法结合使用，以鉴定由该替代RNA聚合酶调节的基因。