Mechanisms of Prion Spread

朊病毒传播机制

基本信息

批准号：
9403142
负责人：
Christina Sigurdson
金额：
$ 33.91万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN DIEGO
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-09-15 至 2022-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9403142
关键词：
Affect Alpha Cell Alzheimer&apos s Disease Amyotrophic Lateral Sclerosis Astrocytes Autophagocytosis Biological Models Brain Brain region Cell membrane Cells Cessation of life Chronic Data Disease Disease Progression Distal Early Endosome Endosomes Functional disorder Funding Goals Human Impairment In Vitro Knockout Mice Lead Lymphoid Tissue Lysosomes Microglia Molecular Conformation Multivesicular Body Mus Muscle Cells Neuraxis Neurodegenerative Disorders Neuroglia Neurons Parkinson Disease Pathologic Pathway interactions Peripheral Nerves Pharmacology Play Post-Translational Protein Processing PrPSc Proteins Presynaptic Terminals Prion Diseases Prion Pathway Prions Property Repression Role Route STEM research Scrapie Site Sorting - Cell Movement Spinal Cord Structure Symptoms Synapses Tauopathies Testing Therapeutic Intervention Vesicle Transport Pathway Virulent astrogliosis base biophysical properties cell type exosome experimental study extracellular genetic regulatory protein in vivo in vivo Model insight late endosome mouse model neuron loss neuronal cell body new therapeutic target physical property prion-like protein aggregate protein expression synucleinopathy trafficking transmission process uptake

项目摘要

Prion diseases are among the most rapidly progressive neurodegenerative disorders and are characterized pathologically by extracellular prion aggregates, synaptic damage, neuronal loss, and severe astrogliosis in the brain and spinal cord. Prion aggregates spread through neuroanatomically connected brain regions, yet how prions physically spread from cell-to-cell is poorly understood. In vitro, prion aggregates form on the plasma membrane, in endosomes, and in multivesicular bodies, and are released in exosomes from chronically infected cells. A major goal of this application is to determine how intra-cellular vesicular prion trafficking contributes to inter-cellular prion spread through the central nervous system using in vitro and in vivo model systems. We have previously employed a broad range of approaches to track structurally diverse prions from axon terminals to neuronal cell bodies and have determined the biophysical properties of highly virulent prions that spread into the CNS. We discovered that small, subfibrillar and fibrillar prions were internalized by neurons through macropinocytosis. However, only the small, subfibrillar prions spread from extraneural sites into the brain. Thus, aggregate size underlies prion spread into the CNS. We also determined that post-translational modifications in the prion protein can alter aggregate packing arrangements and lead to the emergence of new prion strains. Finally, we found that autophagic clearance pathways were induced in muscle cells harboring prion aggregates. In this renewal, we aim to determine how the vesicular trafficking of prions in neurons and glia impacts prion spread through the CNS. In Specific Aim 1, we will define the physical properties of a prion that govern packaging into exosomes. In Specific Aim 2, we will identify key regulators of intracellular prion conversion and clearance in neurons and astrocytes by manipulating vesicular transit pathways. Additionally we will characterize vesicular regulatory protein expression in prion-infected humans and in mouse models. In Specific Aim 3, we will determine how cell-specific repression of early and late stages of vesicular trafficking modifies prion disease progression. These experiments are the first to probe the contribution of intra-vesicular prion trafficking pathways to prion spread in vivo, and will help unravel how vesicular transport impacts prion conversion, clearance, and rapid spread through the brain. The proposed studies are particularly important with the growing recognition of endosomal and lysosomal dysfunction occurring in Alzheimer’s and other neurodegenerative diseases, and with potential opportunities arising for therapeutic intervention in protein aggregate clearance pathways.

病毒疾病是最迅速进行性神经退行性疾病之一，是在病理上以细胞外pr骨骨料，突触损伤，神经元丧失，大脑和脊髓中的严重星形胶质病。 prion骨料通过神经解剖学上连接的大脑区域，但是prions从细胞到细胞的物理传播的方式是理解不佳。在体外，在质膜上形成prion骨料，内体和在多质体中，并在慢性感染细胞的外泌体中释放。专业该应用的目的是确定细胞内囊泡pr贩的有助于细胞间的prion在体外和体内模型通过中枢神经系统扩散系统。我们以前已经采用了广泛的方法来跟踪结构从轴突末端到神经元细胞体的各种prion虫，并确定了生物物理散布到中枢神经系统的高度毒物的特性。我们发现那很小亚纤维和原纤维王因通过大型细胞增多症而被神经元内化。然而，只有小的亚纤维prions从外部部位扩散到大脑。那，汇总大小是王室扩散到中枢神经系统中的。我们还确定了翻译后 prion蛋白的修饰可以改变骨料包装布置并导致新的pr菌菌株的出现。最后，我们发现自噬清除途径是诱导的肌肉细胞具有prion骨聚集体。在此续约中，我们旨在确定神经元和神经胶质的冠军的囊泡贩运会影响毒a在中枢神经系统中传播。在具体目标1，我们将定义管理包装中的prion的物理特性外泌体。在特定的目标2中，我们将确定细胞内prion trust依的关键调节因子和通过操纵囊泡途径的神经元和星形胶质细胞中的清除率。另外，我们将表征囊泡调节蛋白在原始感染的人和小鼠中的表达型号。在特定目标3中，我们将确定早期和晚期的细胞特异性表示囊泡贩运修饰符的阶段。这些实验是首先要探测腔内pr贩途径对prion prion在体内扩散的贡献，并将有助于解开囊泡运输如何影响王室的转换，清除和快速通过大脑传播。拟议的研究在增长时尤其重要识别阿尔茨海默氏症和其他人发生的内体和溶酶体功能障碍神经退行性疾病，并带有治疗干预的潜在机会在蛋白质骨料清除途径中。