ROLE OF YAPS IN Y. PESTIS PATHOGENESIS

雅普病在鼠疫杆菌发病机制中的作用

• 批准号: 7812704
• 负责人: VIRGINIA L MILLER
• 金额: $ 36.76万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-05-15 至 2011-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7812704
• 关键词: Acute; Address; Amino Acids; Animal Model; Antibodies; Bacterial Adhesins; Biological; Biological Assay; Bioterrorism; Blood; Cell surface; Computer Simulation; Country; Cytotoxin; Data; Disease; Disease Outbreaks; Enterobacteriaceae; Escherichia coli; Fever; Fleas; Future; Genome; Goals; Histology; Human; In Vitro; Individual; Infection; Insecta; Laboratories; Life Cycle Stages; Lung; Measures; Membrane; Modeling; Molecular; Molecular Genetics; Mus; Mutation; N-terminal; Organism; Outcome Study; Pathogenesis; Peptide Hydrolases; Peptide Signal Sequences; Phenotype; Plague; Play; Pneumonic Plague; Probability; Production; Proteins; Public Health; Reporter; Rodent; Role; Route; Septicemic plague; Sequence Analysis; Structure; Surface; System; Testing; Trees; Vaccines; Virulence; Virulent; Western Blotting; Work; Yersinia pestis; base; cytokine; genetic manipulation; human morbidity; in vivo; interest; mortality; mouse model; mutant; novel; pathogen; research study; sucking; therapeutic target; tool; transmission process; vaccine development

Yersinia pestis is a Gram-negative bacterial human pathogen that is the causative agent of plague. Historically Y. pestis has been responsible for significant human morbidity and mortality. However, Y. pestis is typically a pathogen of rodents, and is unique among the Enterobacteriaceae in using a blood-sucking insect (flea) for transmission. Y. pestis infection in humans is an acute febrile disease that can have a number of different presentations depending upon the route of inoculation. Although environmental outbreaks of plague in the developed world largely have been controlled, the possible use of this pathogen as an agent of bioterrorism, as well as the re-emergence of plague in several countries, necessitates a more detailed understanding of the pathogenesis of Y. pestis to facilitate the identification of targets for vaccine development and treatment. No vaccine is currently available. A group of proteins that have a high likelihood of contributing to Y. pestis pathogenesis are the autotransporter proteins (ATs). AT proteins consist of three basic domains: a N-terminal signal sequence, a ¿passenger domain¿ and finally a β-domain at the C-terminus which facilitates translocation of the passenger domain across the outer membrane. The passenger domain provides the functional activity and new activities are being attributed to these proteins as more of them are studied in detail. While the β-domains are relatively conserved between ATs the passenger domains can vary significantly. In silico analyses have identified ten AT proteins of Y. pestis (designated yaps/Yaps). The Yaps are of interest to study for a number of reasons. First, while many putative AT proteins have been identified by in silico analyses, relatively few have been studied experimentally and even fewer have been studied in detail. With Y. pestis we have the advantage of being able to pair sophisticated molecular genetic manipulations with an animal model that is actually a natural host for this pathogen. Second, many of the Yaps by sequence analysis are relatively divergent when evolutionary trees of ATs are constructed and thus, the likelihood of identifying new functions by studying this group of ATs is high. Third, analysis of the Yaps may help identify a useful therapeutic target or candidate for inclusion in upcoming Y. pestis vaccine cocktails. We have preliminary data indicating that all ten of the yaps are expressed not only during laboratory conditions but also during infection. We also have constructed deletion mutants in seven yaps in a fully virulent Y. pestis strain and have begun testing the effect of these mutations on virulence. Four yap mutants clearly have phenotypes in a bubonic plague model of infection; these results are consistent with our hypothesis that the yaps play a role in pathogenesis. Our long term goal is to understand at a molecular level the role(s) of the individual Yaps in disease and the Y. pestis life cycle. Thus, we propose the following specific aims: (1) Analysis of the localization and expression of Yaps in Y. pestis; (2) Analysis of the role of Yaps in virulence; (3) Analysis of potential functions of the Yaps.

鼠疫耶尔森氏菌是一种革兰氏阴性细菌，是鼠疫的病原体。从历史上看Y.鼠疫是人类发病率和死亡率居高不下的原因。然而，Y.鼠疫通常是啮齿类动物的病原体，并且在肠杆菌科中是独特的，其利用吸血昆虫（跳蚤）进行传播。Y.人类感染鼠疫是一种急性发热性疾病，根据不同的接种途径会有不同的表现。虽然鼠疫在发达国家的环境爆发已基本得到控制，但这种病原体可能被用作生物恐怖主义的媒介，以及鼠疫在几个国家的重新出现，需要更详细地了解Y.鼠疫，以促进确定疫苗开发和治疗的目标。目前没有疫苗可用。一组很可能导致Y染色体的蛋白质。鼠疫 发病机制是自转运蛋白（AT）。AT蛋白由三个基本结构域组成：N-末端信号序列，乘客结构域和C-末端的-结构域，其促进乘客结构域跨外膜的易位。乘客结构域提供了功能活性，并且随着对更多蛋白质的详细研究，新的活性被归因于这些蛋白质。虽然-结构域在AT之间相对保守，但是乘客结构域可以显著变化。计算机模拟分析已经鉴定出10种Y.鼠疫（命名为雅普/雅普）。雅普人之所以值得研究，有几个原因。首先，虽然许多假定的AT蛋白已经通过计算机分析鉴定， 实验研究相对较少，详细研究的就更少了。与Y。我们的优势是能够将复杂的分子遗传操作与实际上是这种病原体的天然宿主的动物模型配对。第二，当构建AT的进化树时，通过序列分析的许多Yap相对发散，因此，通过研究这组AT来识别新功能的可能性很高。第三，对Yaps的分析可能有助于确定一个有用的治疗靶点或候选者，以纳入即将到来的Y。鼠疫疫苗鸡尾酒我们有初步的数据表明，所有十个yap不仅在实验室条件下，而且在感染过程中表达。我们还在一株完全毒力的Y.并已开始测试其效果 这些突变对毒性的影响。四个雅普突变体在腺鼠疫感染模型中明显具有表型，这些结果与我们的假设一致，即雅普在发病机制中发挥作用。我们的长期目标是在分子水平上了解单个Yaps在疾病和Y。鼠疫的生命周期因此，我们提出了以下具体目标：（1）分析Yaps在Y中的定位和表达。鼠疫菌Yaps的致病性分析;（2）Yaps在鼠疫菌致病性中的作用分析;（3）Yaps潜在功能分析。