Modulation of Rab7-Dependent Degradative Pathways by Novel Adenovirus Protein

新型腺病毒蛋白对 Rab7 依赖性降解途径的调节

基本信息

批准号：
7995957
负责人：
CATHLEEN R CARLIN
金额：
$ 31.54万
依托单位：
CASE WESTERN RESERVE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-12-01 至 2012-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7995957
关键词：
Acute Adenovirus Infections Adenovirus Protein Adenoviruses Ankyrin Repeat Antigen Presentation Binding Cell Polarity Cell Surface Receptors Cells Cellular biology Cholesterol Cholesterol Homeostasis Chronic Chronic Obstructive Airway Disease Complex Cytoplasm DNA Viruses Data Degradation Pathway Disease Disease model Dynein ATPase Endocytosis Endoplasmic Reticulum Endosomes Ensure Epidermal Growth Factor Receptor Equilibrium Evolution Failure Fibroblasts Foundations GTP Binding Gene Expression Gene Transduction Agent Genes Goals Grant Review Guanosine Triphosphate Guanosine Triphosphate Phosphohydrolases Health Human Adenoviruses IL8 gene Immune response Infection Inflammatory Integral Membrane Protein Invaded Ligands Light Lipids Lung diseases Lysosomes Maintenance Mediating Membrane Protein Traffic Microtubules Modification Molecular Monomeric GTP-Binding Proteins Motor Normal Cell Nuclear Pore Complex Nuclear Translocation Nutrient Organelles Pathogenesis Pathologic Processes Pathway interactions Patients Phenotype Pneumonia Production Proliferating Protein Binding Proteins Public Health Receptor Down-Regulation Receptor Protein-Tyrosine Kinases Receptor Signaling Recruitment Activity Recycling Regulation Research Risk Factors Role Sequence Homology Signal Transduction Sorting - Cell Movement Spectrin Sterols Stress Supraoptic Vertical Ophthalmoplegia TNF gene Tail Testing Transport Vesicles Ubiquitin Viral Yeasts base cellular targeting cholesterol trafficking design disorder risk dynactin endosome membrane extracellular human disease insight late endosome loss of function mimicry nervous system disorder novel palmitoylation pathogen receptor receptor expression research study trafficking

项目摘要

DESCRIPTION (provided by applicant): Endocytosis serves many important functions ranging from acquisition of extracellular nutrients to regulation of cell surface receptor expression and signal transduction, maintenance of cell polarity, and antigen presentation. Many intracellular pathogens hijack endocytic pathways in order to invade cells, proliferate, and ensure pathogen survival. Understanding the consequences of pathogenic infection has enabled greater understanding of the endocytic trafficking machinery. Isolated pathogenic genes have also been used to curb pathological processes associated with their cellular targets in human disease models. The focus of this proposal is to understand the molecular and cellular mechanisms employed by an integral membrane protein encoded by the early region 3 of human adenoviruses called RID?, which was originally identified because of its ability to divert constitutively recycling EGF receptors to lysosomes. We have recently discovered that RID? interacts with RILP and ORP1L, two known effectors for the Rab7 GTPase that governs transport from early to late endosomes and then to lysosomes. Importantly, RID? compensates for Rab7 loss-of-function, suggesting it modifies endosome membrane dynamics by coordinating recruitment of Rab7 effectors to compartments that would ordinarily be perceived as early sorting endosomes. To our knowledge this is the first protein encoded by a DNA virus that functions by Rab7 mimicry. Similar to other small GTPases, Rab7 acts by cycling between an active GTP- bound state and an inactive GDP-bound state. In contrast RID? is a non-enzymatic intrinsic membrane protein that lacks any sequence homology to Rab7, providing a remarkable example of convergent evolution. Four specific aims will test these hypotheses. 1) RID? controls microtubule-dependent vesicle transport by recruiting RILP and ORP1L which then activate minus end-directed dynein-dynactin motors. 2). RID?- RILP facilitates ESCRT-II-dependent EGF receptor sorting independent of receptor tyrosine kinase or ubiquitin status. 3) RID?-ORP1L regulates cholesterol efflux from endosomes necessary to maintain the proper lipid balance in cells. 4) RID? compensates for Rab7 loss-of-function during a productive adenovirus infection, and blunts adenovirus-induced inflammatory disease by interfering with a TNF?-EGF receptor signaling cascade that regulates IL-8 production. Altogether these studies will provide novel insights to the cell biology of membrane protein trafficking, and also the molecular basis for adenovirus-induced inflammatory disease. PUBLIC HEALTH RELEVANCE The proposed studies are relevant to public health because they will provide novel insights to the molecular pathogenesis of adenovirus pneumonia. They will generate new strategies for design of non-toxic adenovirus-based gene therapy vectors, and benefit patients with chronic obstructive pulmonary disease (COPD) and other chronic respiratory diseases where it is thought persistent adenovirus infections are an important disease risk factor. These studies will also provide the foundation for developing new treatments for patients with Niemann-Pick C disease, a progressive neurological disease that is always fatal.

描述（由申请人提供）：内吞作用具有许多重要的功能，从获得细胞外营养素到调节细胞表面受体表达和信号转导，维持细胞极性和抗原表现。许多细胞内病原体劫持了内吞途径，以侵入细胞，增殖并确保病原体存活。了解致病感染的后果已使人们对内吞运输机制有了更深入的了解。分离的致病基因也已用于遏制与其细胞靶标相关的病理过程。该提案的重点是了解由人类腺病毒早期腺病毒所编码的积分膜蛋白所采用的分子和细胞机制称为RID？，最初被鉴定出来的，因为它具有将EGF受体转移到溶酶体上的构造性回收性回收的能力。我们最近发现了那个RID吗？与RILP和ORP1L相互作用，RAB7 GTPase的两个已知效应子，该效应子从早期到后期到晚期的运输，然后是溶酶体。重要的是，放弃？补偿了RAB7功能丧失，这表明它通过协调RAB7效应子的募集到通常被视为早期分类内体的隔间来修饰内体膜动力学。据我们所知，这是第一种由Rab7模仿起作用的DNA病毒编码的蛋白质。与其他小型GTP酶相似，RAB7通过在活性GTP结合状态和不活跃的GDP结合状态之间循环起作用。相反，摆脱了？是一种非酶的内在膜蛋白，缺乏与RAB7同源的任何序列同源性，提供了一个非凡的收敛进化例子。四个具体目标将检验这些假设。 1）骑吗？通过募集RILP和ORP1L来控制微管依赖性囊泡的转运，然后激活减去终端导向的动力蛋白 - 二奈霉素电动机。 2）。 RID？ - RILP促进独立于受体酪氨酸激酶或泛素状态的ESCRT-II依赖性EGF受体分选。 3）rid？-orp1l调节所需内体的胆固醇外排，以维持细胞中适当的脂质平衡。 4）骑吗？通过干扰调节IL-8产生的TNF？-EGF受体信号级联，弥补了生产性腺病毒感染期间的RAB7功能丧失，并通过干扰TNF？-EGF受体信号级联，从而弥补腺病毒诱导的炎症性疾病。这些研究总的来说，将为膜蛋白运输的细胞生物学以及腺病毒诱导的炎症性疾病的分子基础提供新的见解。公共卫生相关性与拟议的研究与公共卫生有关，因为它们将为腺病毒肺炎的分子发病机理提供新的见解。他们将生成新的策略，用于设计基于腺病毒的基因疗法载体，并使慢性阻塞性肺疾病（COPD）和其他慢性呼吸道疾病的患者受益于持续性腺病毒感染是重要的疾病风险因素。这些研究还将为Niemann-Pick C疾病患者开发新疗法的基础，这是一种始终致命的进行性神经系统疾病。