Role of MiT Transcription Factors in Host Defense Against Bacterial Infection

MiT 转录因子在宿主防御细菌感染中的作用

• 批准号: 8610327
• 负责人: Javier Elbio Irazoqui
• 金额: $ 38.92万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-04-01 至 2017-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8610327
• 关键词: Address; Animal Model; Apical; Bacteria; Bacterial Infections; Binding; Biochemical; Biogenesis; Biological; Caenorhabditis elegans; Cell Line; Cell physiology; Cell surface; Cells; Chronic; Communicable Diseases; Complement Factor B; Coupled; Defect; Detection; Development; Discrimination; Disease; Enterobacteriaceae; Epithelial Cells; Exhibits; Family; Gene Expression Profiling; Gene Targeting; Genes; Genetic Models; Genetic Transcription; Goals; Homologous Gene; Host Defense; Human; Immune response; In Vitro; Infection; Infection Control; Inflammation; Inflammatory; Inflammatory disease of the intestine; Intestines; Knowledge; Ligands; Link; Lysosomes; Malignant Neoplasms; Mediating; Microbe; Mission; Modeling; Molecular; NF-kappa B; Outcome; Pathogen detection; Pathogenesis; Pathway interactions; Patients; Play; Post-Translational Protein Processing; Prevention; Prevention approach; Public Health; Publishing; Regulation; Research; Role; Sepsis; Signal Pathway; Signal Transduction; Stream; Surface; TFE3 gene; Testing; Time; Toll-like receptors; United States National Institutes of Health; Work; antimicrobial; base; chromatin immunoprecipitation; genetic analysis; in vivo; innovation; insight; intestinal epithelium; methicillin resistant Staphylococcus aureus; microbial; novel; pathogen; pathogenic bacteria; promoter; public health relevance; receptor; response; tool; transcription factor

DESCRIPTION (provided by applicant): A key function of the intestinal epithelium is to discriminate commensal from pathogenic microbes and thus avoid infectious disease and chronic inflammation; however, little is known about how intestinal epithelial cells (IECs) sense bacteria at the apical surface and transduce the signals to drive appropriate transcriptional responses. The long-term goal of this research is to elucidate relationships between IEC and microbe regulatory networks that determine the outcome of host-microbe interactions in vivo. The overall objective of this proposal is to elucidate pathways mediated by MITF-TFE (MiT) family transcription factors (TFs) that determine the host IEC response to infection. Because MiT family TFs are highly conserved, we chose to use Caenorhabditis elegans, a genetically tractable model organism, as a tool to address these questions. C. elegans exhibits pathogen-specific responses that are independent of TLR, NLR, and NF-kB, and thus represents a useful tool to study novel host defense pathways that are evolutionarily conserved, in an unbiased manner in vivo. The central hypothesis of this proposal is that unknown signaling pathways activated during pathogenic infection control MiT-mediated host defense in C. elegans and human IECs. The rationale for the proposed research is that, once it is understood how MiT TFs function in the host response and how they are regulated in vivo, their activity could likely be manipulated pharmacologically, resulting in new and innovative approaches for the prevention and treatment of a variety of infectious or inflammatory diseases. To test the central hypothesis, three specific aims are proposed: 1) Elucidate upstream regulators of HLH-30/MiT, using mosaic genetic analysis, biochemical characterization of post-translational modifications, and genetic analysis of candidate upstream pathways; 2) Elucidate downstream target pathways of HLH-30/MiT, using global gene expression profiling and chromatin immunoprecipitation approaches, and 3) Elucidate the role of MiT TFs in human IEC host defense, using human IEC lines in biochemical, molecular, and cell biological approaches cou- pled with high-throughput gene expression profiling. The contribution of the proposed research is expected to be the elucidation of novel, non-TLR/NLR/NF-¿B, HLH-30/MiT-mediated pathways regulating the host response to bacteria in C. elegans and human IECs. These contributions are significant because they are the first step in a continuum of research that will eventually allow pharmacologic manipulation of host defense via MiT signaling, either positively or negatively, to treat infection or inflammatory disease. The proposed research is conceptually innovative because it shows for the first time that MiT TFs are differentially expressed in human IECs during microbial stimulation and intestinal inflammation.Furthermore, the proposed research is innovative because it represents a departure from more directed in vitro approaches and takes advantage of the tractability of C. elegans, and thus is an unbiased and efficient in vivo approach.

描述（由适用提供）：肠上皮的关键功能是将共生与致病性微生物区分开来，从而避免传染病和慢性感染；但是，关于肠上皮细胞（IEC）如何在顶部表面感知细菌并转导信号以驱动适当的转录反应的知识知之甚少。这项研究的长期目标是阐明IEC和微生物调节网络之间的关系，这些网络确定了体内宿主微生物相互作用的结果。该提案的总体目的是阐明由MITF-TFE（MIT）家族转录因子（TFS）介导的途径，这些途径决定了宿主IEC对感染的宿主反应。由于MIT家族TF是高度保守的，因此我们选择使用秀丽隐杆线虫（一种通用的模型有机体）作为解决这些问题的工具。秀丽隐杆线虫表现出与TLR，NLR和NF-KB无关的病原体特异性反应，因此代表了一种有用的工具，可以在体内以公正的方式研究新型的宿主防御途径。该提案的中心假设是在病原感染控制MIT介导的秀丽隐杆线虫和人IEC中激活的未知信号通路。拟议的研究的理由是，一旦了解了MIT TFS在宿主反应中的功能以及如何在体内调节它们，则可能会通过药理学操纵其活性，从而为预防和治疗各种感染性或炎症性疾病提供新的创新方法。为了检验中心假设，提出了三个具体目的：1）使用马赛克遗传分析，翻译后修饰的生化表征以及对候选途径的遗传分析的生化特征，阐明HLH-30/MIT的上游调节剂； 2）使用全球基因表达分析和染色质免疫沉淀方法阐明了HLH-30/MIT的下游目标途径，3）阐明了MIT TFS在人IEC宿主防御中的作用，使用人IEC在生化，分子生物学和细胞生物学方法中使用人IEC线条在人IEC宿主防御中的作用，并以高位化的基因表达基因表达基因表达。拟议研究的贡献预计将是对新型，非TLR/NLR/NF-¿B，HLH-30/MIT介导的途径的阐明，这些途径调节了秀丽隐杆线虫和人IEC中细菌的宿主反应。这些贡献是重要的，因为它们是连续研究的第一步，最终将通过MIT信号（正面或负面的）来治疗感染或炎症性疾病，最终可以通过MIT信号对宿主防御进行药物进行宿主防御。拟议的研究在概念上具有创新性，因为它首次表明MIT TF在微生物刺激和肠道感染期间在人IEC中的表达不同。FurThermore，拟议的研究具有创新性，因为它代表了与更有指导性的体外方法的背离，并利用了Elemans C. elemans的障碍，因此是无限态度的viv，并有效地是vivo and viv viv。