Cytoskeletal machinery driving invasion by the human pathogen, Toxoplasma gondii.

细胞骨架机制驱动人类病原体弓形虫的入侵。

• 批准号: 10294822
• 负责人: Ke Hu
• 金额: $ 41.64万
• 依托单位: ARIZONA STATE UNIVERSITY-TEMPE CAMPUS
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10294822
• 关键词: Actomyosin; Antiparasitic Agents; Apical; Apicomplexa; Automobile Driving; Biochemical; Biophysics; Blindness; Calcium; Cells; Complex; Cytoskeletal Proteins; Defect; Development; Drug Targeting; Evolution; Fetus; Goals; Hand; Higher Order Chromatin Structure; Human; Image; Immunocompromised Host; Impairment; In Vitro; Individual; Infection; Invaded; Lead; Left; Link; Mechanics; Membrane; Methodology; Microtubules; Modeling; Molecular; Motor; Neurologic; Ocular Toxoplasmosis; Opportunistic Infections; Organelles; Orthologous Gene; Parasites; Planet Earth; Plant Roots; Polymers; Protein Secretion; Proteins; Regulation; Retina; Role; Structure; Testing; Toxoplasma gondii; Toxoplasmosis; Tubulin; Variant; Work; cell cortex; cell motility; gene discovery; human pathogen; in vivo; mutant; novel; obligate intracellular parasite; parasite invasion; prevent; toxoplasmic encephalitis

Project Summary: Approximately 20% of the people on Earth are permanently infected with the unicellular parasite, Toxoplasma gondii. T. gondii is one of the leading causes of congenital neurological defects in humans, and an agent for devastating opportunistic infections in immunocompromised individuals. Ocular toxoplasmosis is one of the most common retinal infections and can lead to blindness. As an obligate intracellular parasite, T. gondii must first invade cells of its host in order to replicate. In the preliminary study, we found that the disruption of an iconic structure in T. gondii, the conoid, is linked to drastically impaired invasion. This is an aspect of invasion that has not been explored, as previous work on invasion has mainly centered on the regulation and activity of the actomyosin motor complex and protein secretion from specialized membrane-bound organelles. To explore this new direction, we propose two complementary aims to (a) determine the function of the conoid in host cell invasion (Aim 1), and (b) elucidate how this novel cytoskeletal complex is constructed (Aim 2). Using the mutants we have generated, Aim 1 will determine whether the conoid facilitates invasion by secretion, motility, directly assisting the physical interaction between the parasite and the host cell during attachment, or overcoming the cortical tension of the host cell. Aim 2 will identify and characterize structural determinants of the conoid by integrating gene discovery with structural and functional analyses. We will combine state of the art imaging, biophysical, biochemical, and evolutionary approaches. This comprehensive strategy will greatly enhance our ability to identify novel components in this unique structure as drug targets.

项目摘要： 地球上约有20％的人永久感染了单细胞寄生虫， 弓形虫弓形虫。 T. gondii是先天性神经系统缺陷的主要原因之一 人类，以及免疫功能低下的个体毁灭性机会感染的代理。 眼癌是最常见的视网膜感染之一，可能导致失明。作为 巨大的细胞内寄生虫，T。gondii必须首先入侵其宿主的细胞才能复制。在 初步研究，我们发现T. gondii（Conoid）中标志性结构的破坏与蛋白酶的破坏与 入侵严重受损。这是尚未探索的入侵的一个方面，就像以前 入侵的工作主要集中于肌动球蛋白运动复合物的调节和活动 以及来自特殊膜结合细胞器的蛋白质分泌。为了探索这个新的方向，我们 提出了两个补充目的，以（a）确定蛋白酶在宿主细胞侵袭中的功能（AIM 1）和（b）阐明了如何构建这种新型细胞骨架复合物（AIM 2）。使用突变体我们 已经产生的，AIM 1将确定蛋白酶是否通过分泌，运动性促进入侵 在附着期间直接协助寄生虫与宿主细胞之间的物理相互作用，或 克服宿主细胞的皮质张力。 AIM 2将识别和表征结构 通过将基因发现与结构和功能分析的基因发现整合来决定蛋白酶的决定因素。我们 将结合艺术成像，生物物理，生化和进化方法的状态。这 全面的策略将大大增强我们在这种独特的情况下识别新颖组成部分的能力 作为药物靶标的结构。