Exploratory Studies of lp17-encoded Genetic Factors Important for Tick Colonization by the Lyme Disease Spirochete

对莱姆病螺旋体蜱定殖重要的 lp17 编码遗传因子的探索性研究

• 批准号: 10373101
• 负责人: Troy Michael Bankhead
• 金额: $ 22.95万
• 依托单位: WASHINGTON STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-03-16 至 2024-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10373101
• 关键词: Animals; Area; Arthritis; Arthropods; Black-legged Tick; Borrelia burgdorferi; Carditis; Cell Density; Chemicals; Chromosomes; Clinical; Clonal Deletion; Complement; Complex; Data; Development; Environment; Gene Expression; Gene Expression Regulation; Generations; Genes; Genetic; Genome; Global Change; Goals; Health; Human; Immunofluorescence Immunologic; Impairment; In Vitro; Infection; Infection prevention; Intercistronic Region; Investigation; Knowledge; Larva; Lead; Life Cycle Stages; Lyme Disease; Lyme Infection; Maps; Measures; Mediating; Midgut; Mission; Molting; Mus; Nature; Neurologic; North America; Nymph; Parasites; Phenotype; Plasmids; Public Health; Publishing; RNA; Regulation; Research; Rest; Role; Salivary Glands; Starvation; System; Temperature; Testing; Therapeutic; Tick-Borne Diseases; Ticks; United States National Institutes of Health; Untranslated RNA; Vaccines; Work; base; cohort; differential expression; disability; effective therapy; enzootic; feeding; genetic approach; host colonization; human pathogen; mutant; new therapeutic target; novel; pathogen; prevent; tick feeding; tick transmission; time use; transmission process; vaccine development; vector tick

Project Summary Borrelia burgdorferi is an obligate parasite, and is maintained in nature through a complex cycle involving both a tick and mammalian host. The transition between these two very different host types requires the ability to rapidly adapt through changes in gene expression. B. burgdorferi possesses a segmented genome comprised of a single linear chromosome and upwards of 23 linear and circular plasmids. Previous studies have provided information on a number of genes that may be differentially expressed under conditions intended to mimic that of the vertebrate or arthropod host. However, investigation has only just begun to elucidate the importance of lp17 for colonization of the host and tick vector by B. burgdorferi. Published and preliminary work in our lab has recently shown that a small non-coding RNA and the bbd21 gene encoded on lp17 have roles in the regulation of genes important for host adaptation. Despite these advances, there remains a fundamental gap in our understanding of the role and function of many genes for adaptation to the tick vector. Our long-term goal is to identify and characterize factors necessary for B. burgdorferi adaptation to the tick and mammalian host environments. The overall objective of this application is to identify lp17-resident genes required for colonization of the tick vector by B. burgdorferi. Based on published work and preliminary data, the central hypothesis of this proposal is that a number of lp17-resident genes of B. burgdorferi are important for tick colonization, survival, and/or transmission. The rationale for the proposed research is that these identified factors will represent potential targets for the development of a vaccine and/or therapeutics against human infection by the Lyme disease pathogen, as well as targeting factors critical for its enzootic life cycle. Thus, the proposed research is relevant to that part of NIH’s mission that pertains to developing fundamental knowledge that will potentially help to reduce the burdens of human illness and disability. Guided by cited work and preliminary data, our hypothesis will be tested by pursuing the following specific aim and two sub aims: 1) Determine the requirement of lp17-resident genes for tick acquisition, survival, and/or transmission of Bb. Under the first sub aim, Ixodes scapularis tick larvae will first be infected with either wild type or lp17 mutant B. burgdorferi clones using a novel continuous flow tick feeding system to identify genetic regions of lp17 important for tick acquisition and transstadial survival. Under the second sub aim, nymphal ticks infected with either a lp17 mutant or wild type control will be allowed to feed for a given time using our tick feeding system, after which the bacterial burden in isolated midgut and salivary glands will be assessed via immunofluorescence analysis. When applied, the results from the proposed studies are expected to ultimately lead to new control measures to disrupt the pathogen’s enzootic cycle and prevent infection by the Lyme disease spirochete.

项目摘要 Borrelia burgdorferi是一种卑鄙的寄生虫，并且通过复杂的循环在自然界中保持 涉及tick虫和哺乳动物主人。这两种非常不同的主机类型之间的过渡需要 通过基因表达变化快速适应的能力。 B. Burgdorferi拥有一个分段 基因组完成了单个线性染色体，超过23个线性和圆形质粒。以前的 研究提供了有关许多基因可能在条件下表达不同的基因的信息 旨在模仿脊椎动物或节肢动物宿主的脊椎动物。但是，调查才刚刚开始 阐明了B. Burgdorferi的LP17对宿主和tick矢量定殖的重要性。出版和 我们实验室的初步工作最近表明，编码的小非编码RNA和BBD21基因 LP17在对宿主适应至关重要的基因调节中具有作用。尽管有这些进步， 我们对许多基因适应的作用和功能的理解仍然是一个根本的差距 刻度矢量。我们的长期目标是确定并表征B. burgdorferi适应所必需的因素 tick和哺乳动物的主机环境。该应用程序的总体目的是确定LP17居民 B. burgdorferi将tick载体定植所需的基因。基于已发表的工作和初步 数据，该提议的核心假设是，伯格多菲利的许多LP17居民基因是 对于壁虱定植，生存和/或传播重要。拟议研究的理由是 这些确定的因素将代表开发疫苗和/或治疗的潜在目标。 反对莱姆病病原体的人类感染，以及靶向因素对其enzootic Life至关重要的因素 循环。这是拟议的研究与NIH使命的那部分有关的研究与发展有关 基本知识将有可能有助于减少人类疾病和残疾的伯恩斯。 在引用的工作和初步数据的指导下，我们的假设将通过追求以下来检验 具体目标和两个子目标：1）确定LP17居民基因对tick获取的需求， BB的生存和/或传播。在第一个子目标下，ixodes肩cap虫幼虫将首先感染 使用一种新型的连续流动式喂食系统到 确定LP17的遗传区域对于获取和跨性生存重要。在第二个潜艇之下 目的，将允许感染LP17突变体或野生型控制感染的若虫壁虱在给定时间内喂食 使用我们的滴答喂食系统，之后，细菌在孤立的中肠和唾液网格中燃烧 通过免疫荧光分析评估。当应用时，预计提出的研究的结果 最终导致新的控制措施破坏病原体的enzootic循环并防止感染 莱姆病螺旋体。