MicroRNA mediated inhibition of apoptosis in Coxiella burnetii infection

MicroRNA介导的伯内氏柯克斯体感染细胞凋亡抑制

• 批准号: 9243896
• 负责人: Rahul Raghavan
• 金额: $ 7.43万
• 依托单位: PORTLAND STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-02-15 至 2019-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9243896
• 关键词: Acute; Affect; Anaplasma phagocytophilum; Antibiotics; Apoptosis; Apoptotic; BCL2 gene; Bacteria; Binding; Biological Assay; Biological Process; Biology; Cells; Chlamydia trachomatis; Chronic; Colorectal; Coxiella; Coxiella burnetii; Data; Development; Disease Outbreaks; Endocarditis; Epidemic; Eukaryota; Gene Targeting; Goals; Growth; Human; Infection; Infection Control; Inhibition of Apoptosis; Knowledge; Mediating; Messenger RNA; MicroRNAs; Molecular; Netherlands; Outcome; Pathogenicity; Pathway interactions; Pharmacologic Substance; Play; Process; Proteins; Public Health; Q Fever; Quantitative Reverse Transcriptase PCR; RNA; RNA analysis; Regulation; Research; Role; Testing; Therapeutic; Translations; Type IV Secretion System Pathway; Untranslated RNA; Vacuole; Work; Zoonoses; base; differential expression; improved; innovation; insight; macrophage; monocyte; mortality; novel; overexpression; pathogen; response; targeted agent; transcriptome sequencing

Project Summary/Abstract The Q fever pathogen Coxiella burnetii inhibits apoptosis (programmed cell death) in host cells in order to replicate in a stable intracellular compartment. Effector proteins secreted by Coxiella into host cell have been shown to inhibit apoptosis, although their mechanisms of action are not fully understood. Additionally, no information is currently available about the roles host microRNAs (miRNAs) potentially play in regulating apoptosis in Coxiella-infected cells. miRNAs are ~22 nt RNAs that regulate several biological processes in human cells, including apoptosis, by binding to target mRNAs and either blocking translation or causing target degradation. Our long-term goal is to understand how non-coding RNAs regulate Coxiella-host interactions. Towards attaining this goal, the objective of this application is to identify miRNAs that have a role in inhibiting apoptosis during Coxiella infection. Based on preliminary data that revealed potential functions for apoptosis-related miRNAs in Coxiella-infected macrophages, our central hypothesis is that miRNAs have a role in delaying apoptosis during Coxiella infection. The objective of this project will be accomplished by three specific aims: (1) Identify miRNAs that are induced or repressed by Coxiella infection. Using RNA-seq and qRT-PCR we will identify all miRNAs that are differentially expressed in Coxiella- infected THP-1 (human monocyte/macrophage) cells. (2) Determine miRNAs that inhibit apoptosis during Coxiella infection. For the miRNAs identified in our preliminary studies and in Aim 1, we will assay their ability to inhibit apoptosis. (3) Define the role of miR-148a during Coxiella infection. To begin to understand at a molecular level how miRNAs facilitate inhibition of apoptosis during Coxiella infection, we will interrogate the function of miR-148a. This miRNA was chosen because it was significantly down-regulated in Coxiella-infected cells in our preliminary analysis, and its target gene (Bcl-2) has critical roles in both C. burnetii development and apoptosis inhibition. The research proposed here is innovative, because it will depart from the status quo to investigate a whole new realm of host-pathogen dynamics: the RNA-level interaction between Coxiella and human cells. This work is significant because this will be the first study to uncover the roles of miRNAs during Coxiella infection, and based on our results, novel pharmaceutical agents that target miRNAs could potentially be developed to control chronic Coxiella infections, which are difficult to treat with currently available antibiotics. Our approach and results could also be broadly applied to studying the functions of miRNAs during infections caused by other intracellular pathogens.

项目概要/摘要 Q 热病原体伯氏柯克斯体抑制宿主细胞的凋亡（程序性细胞死亡） 以便在稳定的细胞内区室中复制。柯克斯体分泌的效应蛋白 宿主细胞已被证明可以抑制细胞凋亡，但其作用机制尚不完全清楚。 明白了。此外，目前没有关于宿主 microRNA 的作用的信息 (miRNA) 可能在调节柯克斯体感染细胞的细胞凋亡中发挥作用。 miRNA 是~22 nt RNA 通过与靶标结合来调节人体细胞中的多种生物过程，包括细胞凋亡 mRNA 会阻碍翻译或导致靶标降解。我们的长期目标是 了解非编码 RNA 如何调节柯克斯体与宿主的相互作用。为了实现这一目标， 本申请的目的是鉴定在细胞凋亡过程中具有抑制细胞凋亡作用的 miRNA。 柯克斯体感染。基于揭示细胞凋亡相关潜在功能的初步数据 考克斯体感染的巨噬细胞中的 miRNA，我们的中心假设是 miRNA 在 延缓柯克斯体感染期间的细胞凋亡。该项目的目标将通过 三个具体目标：(1) 鉴定由 Coxiella 感染诱导或抑制的 miRNA。使用 RNA-seq 和 qRT-PCR 我们将鉴定 Coxiella 中差异表达的所有 miRNA- 感染THP-1（人单核细胞/巨噬细胞）细胞。 (2)确定抑制细胞凋亡的miRNA 柯克斯体感染期间。对于我们的初步研究和目标 1 中确定的 miRNA，我们将 测定其抑制细胞凋亡的能力。 (3)明确miR-148a在柯克斯体感染过程中的作用。到 开始在分子水平上了解 miRNA 如何促进 Coxiella 细胞凋亡的抑制 感染后，我们将探究 miR-148a 的功能。选择这个 miRNA 是因为它 在我们的初步分析中，在柯克斯体感染的细胞中显着下调，其靶基因 (Bcl-2) 在 C. burnetii 发育和细胞凋亡抑制中发挥关键作用。研究 这里提出的是创新性的，因为它将脱离现状来研究一个全新的 宿主-病原体动力学领域：柯克斯体和人类细胞之间的 RNA 水平相互作用。这 这项工作意义重大，因为这将是第一个揭示 miRNA 在 Coxiella 过程中的作用的研究 感染，并且根据我们的结果，针对 miRNA 的新型药物制剂有可能 开发用于控制慢性柯克斯体感染，目前的方法很难治疗这种感染 抗生素。我们的方法和结果也可以广泛应用于研究 其他细胞内病原体引起的感染期间的 miRNA。