MOTILITY AND INVASIVENESS OF TOXOPLASMA GONDII

弓形虫的活动性和侵袭性

• 批准号: 5205424
• 负责人: JOSEPH D SCHWARTZMAN
• 金额: --
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/5205424
• 关键词: Toxoplasma gondii; cell cycle; cell motility; gene expression; molecular cloning; myosins; nucleic acid sequence; protozoal cyst; site directed mutagenesis; virulence

The goal of this proposal is to develop a strategy to interrupt both acute toxoplasmosis and the reactivation of latent toxoplasmosis based on the absolute necessity of Toxoplasma gondii motility in host cell invasion and the unique mechanism of parasite movement. Active invasion of many host cell types is responsible for the pathology of cerebral and disseminated toxoplasmosis associated with AIDS. A deeper understanding of T. gondii myosin, a likely candidate for the primary motor protein powering gliding movement of myosin, a likely candidate for the primary motor protein powering gliding movement of invasive zoites, may lead to the discovery of drug targets based on inhibition of T. gondii motility. The nucleotide sequence of the T. gondii myosin gene or genes will be deduced from cDNA and genomic libraries by the use of a previously defined 89 bp probe. The predicted protein structure of the full length gene will be compared with known functional domains of heterologous myosin genes. T. gondii myosin genes will be expressed in prokaryote and eukaryote systems in order to analyze biochemical and functional properties of myosin of importance for specific drug design. Antibodies specific for T. gondii myosin within invasive zoites and its function in motility and invasion. Site directed mutagenesis of T. gondii myosin and transformation of T. gondii by altered myosin genes will allow study of the role of myosin in movement and invasiveness, and may provide information on the mechanism of drugs affecting motility. Myosin gene expression will be studied in pathogenic tachyzoite and bradyzoite stages of the asexual cycle, in order to understand the role of myosin in reactivation of bradyzoites in chronic infection. Such reactivation is thought to be the major pathway for initiation of toxoplasmic encephalitis in AIDS. Conditional mutants will be sought that fail to transform to tachyzoites in cell culture, in order to further understand the transition between stages, and to furnish a stable in vitro model for testing pharmacological agents active against bradyzoites.

该提议的目的是制定一种打断既有的战略 急性弓形虫病和潜在弓形虫病的重新激活 关于宿主细胞中弓形虫运动的绝对必要性 入侵和寄生虫运动的独特机制。 积极入侵 在许多宿主细胞类型中，脑部和 与艾滋病相关的传播弓形虫病。 更深入的理解 T. gondii肌球蛋白，可能是主要运动蛋白的候选者 为肌球蛋白的滑行动力动力，肌球蛋白可能是主要的候选者 侵入性Zoites的运动蛋白动力滑行运动可能导致 基于抑制T. gondii运动性的药物靶标的发现。 T. gondii肌球蛋白基因或基因的核苷酸序列将是 从cDNA和基因组文库中推导 定义的89 bp探针。 全长的预测蛋白质结构 基因将与已知的异源功能结构域进行比较 肌球蛋白基因。 T. gondii肌球蛋白基因将在原核生物中表达 真核生系统为了分析生化和功能 对特定药物设计重要性的肌球蛋白的特性。 抗体 特定于入侵Zoites内的T. gondii肌球蛋白及其功能 运动和入侵。 位置指示弓形虫肌球蛋白和诱变的诱变 通过改变肌球蛋白基因对T. gondii的转化将允许研究 肌球蛋白在运动和侵入性中的作用，并可能提供 有关影响运动性的药物机制的信息。 肌球蛋白基因的表达将在致病性速杀中进行研究， 无性循环的Bradyzoite阶段，以了解角色 肌球蛋白在慢性感染中重生的肌球蛋白。 这样的 重新激活被认为是启动的主要途径 艾滋病中的毒质性脑炎。 将寻求有条件的突变体 那未能转化为细胞培养中的tachyzoites，以便 进一步了解阶段之间的过渡，并提供稳定的 用于测试活跃的药理学剂的体外模型 布拉迪二族人。