Dynamin-related protein 1, neurodegeneration and Huntington's disease

动力相关蛋白 1、神经变性和亨廷顿病

基本信息

批准号：
8848902
负责人：
XIN QI
金额：
$ 34.67万
依托单位：
CASE WESTERN RESERVE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-06-01 至 2019-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8848902
关键词：
ATP phosphohydrolase Animal Model Animals Basic Science Behavior Behavioral Biochemical Biological Models Brain Cell Culture Techniques Cell Death Cells Cessation of life Chronic Clinical Research Code Complex Corpus striatum structure DNA Sequence Alteration Data Development Disease Disease model Dynamin Exons Family Genes Glutamine Goals Guanosine Triphosphate Phosphohydrolases Health Human Huntington Disease Impairment In Vitro Length MAPK1 gene Mediating Mitochondria Modeling Molecular Morphology Mus Nerve Degeneration Neurites Neurodegenerative Disorders Neurologic Neurons Pathogenesis Pathology Patients Peptides Play Process Protein-Serine-Threonine Kinases Proteins Proteomics Reagent Role Signal Transduction Symptoms Therapeutic Transgenic Mice Treatment Efficacy Tubular formation Work base bioimaging design effective therapy human Huntingtin protein in vivo induced pluripotent stem cell inhibitor/antagonist member mitochondrial dysfunction motor deficit mouse model mutant neuron loss neuropathology neurotoxicity novel novel strategies novel therapeutic intervention novel therapeutics protective effect protein protein interaction research study tool

项目摘要

DESCRIPTION (provided by applicant): Huntington's disease (HD) is a fatal, autosomal dominant, neurodegenerative disorder caused by a glutamine-coding CAG expansion within exon 1 of the huntingtin gene. Although the genetic mutation associated with the disease has been identified, the molecular and cellular basis of HD is not yet understood and successful treatment for this disease remains elusive. Basic research and clinical studies indicate that mitochondrial dysfunction plays an important role in the pathogenesis of HD. Mitochondria are organized in a highly dynamic tubular network that is continuously reshaped by opposing processes of fusion and fission. Dynamin-related protein 1 (Drp1) is a large GTPase and a key protein governing mitochondrial fission. Recent studies have highlighted the causal role of Drp1-mediated excessive mitochondrial fission in neuronal death in HD cell culture models. However, how Drp1 hyperactivation mediates mitochondrial damage and neurodegeneration in HD and whether pharmacological inhibition of Drp1 activation is sufficient to reduce mutant Htt (mtHtt)-induced neurotoxicity and neurodegeneration are not known. Our recent work showed that Drp1 is translocated to the mitochondria and hyper-activated in both HD cell cultures and in vivo in the HD R6/2 transgenic mouse brain. Importantly, using a novel and selective peptide inhibitor of Drp1, P110, recently developed in our group, we found that inhibition of Drp1-dependent mitochondrial impairment corrected mitochondrial dysfunction and neuronal cell death in HD cell cultures, and reduced behavioral deficits and loss of striatal neurons in HD R6/2 transgenic mice. Moreover, treatment with P110 corrected mitochondrial morphology and reduced neurite loss and cell death in GABAergic striatal neurons derived from HD patient- induced pluripotent stem cells (HD-iPS cells). Further, using unbiased proteomic analysis, we recently profiled the interactome of Drp1 in neuronal cultures derived from HD patient-iPS cells. Our preliminary studies identified two mechanistically distinct candidate proteins (ATADA3, a member of mitochondrial AAA-ATPase family, and MAPK1, a serine/threonine kinase) that are involved in Drp1-mediated neuronal damage. These lines of evidence indicate that Drp1 hyperactivation is a predominant cause of neurodegeneration in HD. Thus, we hypothesize that inhibition of Drp1-mediated mitochondrial damage is a novel approach for reducing neuropathology in HD models in vitro and in vivo. Using biochemical, imaging, bio-energetic, proteomic and pharmacological approaches ranging from animals to patient neurons, our goal in this application is to unravel the complexity of Drp1-mediated mitochondrial dysfunction in neurodegeneration in both mechanistic and therapeutic detail. The proposed study will produce novel information on the role of Drp1-mediated mitochondrial fission in the pathogenesis of HD and provide a useful model system in which to study mitochondrial pathology in striatal neurons. We will also generate pharmacological tools to inhibit HD pathogenesis as a first step towards the development of novel therapeutics for HD.

描述（由申请人提供）：亨廷顿氏病（HD）是一种致命的，常染色体显性症，神经退行性疾病，是由亨廷顿基因外显子1内谷氨酰胺编码CAG扩张引起的。尽管已经确定了与该疾病相关的遗传突变，但尚未了解HD的分子和细胞基础，并且对该疾病的成功治疗仍然难以捉摸。基础研究和临床研究表明，线粒体功能障碍在HD发病机理中起重要作用。线粒体是在高度动态的管状网络中组织的，该网络通过相反的融合和裂变过程不断地重塑。与动力蛋白相关的蛋白1（DRP1）是一个大的GTPase，并且是控制线粒体裂变的关键蛋白质。最近的研究强调了DRP1介导的HD细胞培养模型中神经元死亡中的线粒体裂变过多的因果作用。但是，DRP1过度激活如何介导HD中的线粒体损伤和神经退行性，以及DRP1激活的药理抑制是否足以减少突变HTT（MTHTT）诱导的神经毒性和神经变性。我们最近的工作表明，DRP1转移到线粒体上，并在HD细胞培养物和HD R6/2转基因小鼠脑中过度激活。重要的是，使用最近在我们组中开发的新型和选择性的肽抑制剂P110，我们发现抑制DRP1依赖性的线粒体损伤校正了HD细胞中的线粒体功能障碍和神经元细胞死亡，在HD细胞中培养中的神经元细胞死亡，行为缺陷，而行为缺陷和减少了型在HD r6/2 ry6/2 ry6/2 ry6/2 ry6/2 ry6/2。此外，用p110治疗衍生自HD患者诱导的多能干细胞（HD-IPS细胞）的GABA能纹状体神经元的神经突损失和细胞死亡的校正。此外，使用无偏的蛋白质组学分析，我们最近在衍生自HD患者-IPS细胞的神经元培养物中介绍了DRP1的相互作用组。我们的初步研究确定了参与DRP1介导的神经元损伤的两种机械上不同的候选蛋白（ATADA3，线粒体AAA-ATPase家族的成员和MAPK1，一种丝氨酸/苏氨酸激酶）。这些证据线表明DRP1过度激活是HD神经退行性的主要原因。因此，我们假设抑制DRP1介导的线粒体损伤是一种新型方法，用于减少体外和体内HD模型中神经病理学的方法。使用生化，成像，生物能，蛋白质组学和药理学方法，从动物到患者神经元，我们的目标是在机械和治疗细节中揭示DRP1介导的线粒体功能障碍的复杂性。拟议的研究将产生有关DRP1介导的线粒体裂变在HD发病机理中的作用的新信息，并提供了一个有用的模型系统，可以在其中研究纹状体神经元中的线粒体病理学。我们还将生成药理学工具，以抑制HD发病机理，作为开发HD新治疗剂的第一步。