Caveolae Mediated Bacterial Uptake in the Urinary Tract

小凹介导的尿道细菌摄取

• 批准号: 7440175
• 负责人: Soman N Abraham
• 金额: $ 37.15万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-07-01 至 2011-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7440175
• 关键词: ANXA2 gene; Accounting; Adhesions; Annexins; Area; Bacteria; Binding; Bladder; Caveolae; Cell membrane; Cells; Cholesterol; Classification; Cyclic AMP; Development; Endocytosis; Epithelial Cells; Event; Exocytosis; Exposure to; Goals; Hair; Invaded; Investigation; Lateral; Lipids; Localized; Maps; Mediating; Mediator of activation protein; Membrane; Membrane Microdomains; Mining; Modeling; Mus; Organ; Pharmacotherapy; Prevention; Process; Proteins; Proteome; Proteomics; Recruitment Activity; Recurrence; Research Proposals; Role; Second Messenger Systems; Structure; Surface; Technology; Tyrosine; Urinary tract; Urinary tract infection; Urination; Urine; Uropathogenic E. coli; Vesicle; Virulence Factors; caveolin 1; flotillin; luminal membrane; novel strategies; repository; second messenger; type 1 fimbriae; uptake

DESCRIPTION (provided by applicant): Uropathogenic E.coli (UPEC) account for over 80% of urinary tract infections (UTIs). It is now known invasion of the bladder epithelial cells (BECs) is a critical initiating step in UTIs. We have demonstrated that UPEC invasion is localized to distinct cellular entities in the BEG membrane loosely- termed caveolae. These caveolae are comprised of lateral assemblies of cholesterol, lipids and select proteins such as caveolin-1. We hypothesized that the entry of UPEC into BECs is a highly dynamic event and therefore the host-cell proteins that mediate bacterial entry could be proteins that are selectively recruited to caveolae or become activated within these microdomains following exposure to UPEC. Our initial studies have revealed that two proteins, flotillin-1 and annexin-ll, were recruited to caveolae whereas the third, caveolin-1, became tyrosine-phosphorylated following exposure to UPEC. Another finding emerging from proteome analysis of BECs is that a significant proportion of the proteins identified as caveolar components are known to be regulated by cAMP, a major second messenger implicated in regulating luminal surface area of the bladder by triggering endo- and exocytosis of BEG vesicles which serve as repositories of luminal membranes. This finding, revealed possible parallels between caveolae mediated bacterial entry nto BECs and regular endocytosis of luminal membrane by BECs following voiding of urine. The goal of this research proposal is to extend and expand this line of investigation. Therefore, we propose to: ) Elucidate the mechanism by which flotillin-1, annexin-ll, and caveolin-1 contribute to bacterial entry into 3ECs. (2) Use proteome mining approaches to extend the identification of caveolar components essential for UPEC invasion of BECs.(3) Investigate the regulatory role of cAMP on UPEC invasion of BECs and the mpact of modulators of intracellular cAMP in conferring protection against experimental UTIs. We believe that a systematic approach to the identification of caveolar determinants of bacterial entry will provide a comprehensive picture of the dynamic molecular interactions occurring in the invasion process and also yield candidate proteins that could potentially serve as targets for drug therapy.

描述（由申请人提供）：肝病E.Coli（UPEC）占尿路感染（UTI）的80％以上。现在已知膀胱上皮细胞（BEC）的入侵是UTI中的关键启动步骤。我们已经证明，UPEC入侵位于BEG膜中的不同细胞实体中，该实体松散地称为Caveolae。这些小窝由胆固醇，脂质和选择蛋白（例如小窝蛋白-1）的侧组件组成。我们假设将UPEC进入BEC是一个高度动态的事件，因此介导细菌进入的宿主细胞蛋白可能是蛋白质，在暴露于UPEC后，在这些微区域内被选择性地募集到口腔或在这些微区内被激活。我们的最初研究表明，募集了两种蛋白质Flotillin-1和Annexin-LL，而Caveolin-1则是Caveolin-1，在暴露于UPEC后变成酪氨酸磷酸化。来自BEC的蛋白质组分析中出现的另一个发现是，已知鉴定为Caveolar成分的蛋白质的很大一部分受CAMP调节，这是一个主要的第二信使，涉及通过触发beg囊的内部和外胞菌的调节膀胱的腔表面区域，这些材料是凝聚囊的另一个Messenger，这些材料是腔囊泡的回旋库。这一发现揭示了小窝介导的细菌进入NO BEC和尿液上的BEC的常规内吞作用之间可能的相似之处。这项研究建议的目的是扩展和扩展这一调查范围。因此，我们建议：）阐明氟替金-1，膜联蛋白-LL和小窝蛋白-1促进细菌进入3EC的机制。 （2）使用蛋白质组采矿方法扩展了识别Caveolar成分对于UPEC入侵BEC所必需的。（3）研究CAMP对UPEC入侵BEC的调节作用以及赋予细胞内cAMP调节剂的MPACT，以赋予对实验性UTI的保护。我们认为，一种系统的方法来鉴定细菌进入的洞穴决定因素将为入侵过程中发生的动态分子相互作用提供全面的了解，还可以产生候选蛋白，这些候选蛋白可能有可能作为药物治疗的靶标。