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

• 批准号: 8744411
• 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
• 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/8744411
• 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; Data; Development; Disease; Disease model; Dynamin; Exons; Family; Gene Mutation; Genes; Glutamine; Goals; Guanosine Triphosphate Phosphohydrolases; Human; Huntington Disease; Image; 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; 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; public health relevance; research study; tool

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.

亨廷顿病(HD)是一种致命性常染色体显性遗传性神经退行性疾病，由 亨廷顿蛋白基因外显子1内编码谷氨酰胺的CAG扩增。尽管基因突变 与该病相关的疾病已被确定，HD的分子和细胞基础尚不清楚 这种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的发病机制中起重要作用。线粒体是以一种 高度动态的管状网络，通过相反的融合和裂变过程不断重塑。 动力蛋白相关蛋白1(Dynamin-Related Protein 1，Drp1)是一个大的GTP酶，是控制线粒体分裂的关键蛋白。近期 研究强调了Drp1介导的线粒体过度分裂在神经元死亡中的因果作用。 HD细胞培养模型。然而，Drp1过度激活如何介导线粒体损伤和 HD的神经变性以及药物抑制Drp1激活是否足以减少 突变型Htt(MtHtt)引起的神经毒性和神经变性尚不清楚。我们最近的研究表明， 在HD细胞培养和体内HD中，Drp1被转位到线粒体并被高度激活 R6/2转基因小鼠脑。重要的是，最近使用了一种新的和选择性的Drp1多肽抑制剂p110 在我们组的研究中，我们发现对依赖于Drp1的线粒体损伤的抑制得到纠正 HD细胞培养中线粒体功能障碍和神经细胞死亡，并减少行为缺陷和损失 HD R6/2转基因小鼠纹状体神经元的表达。此外，用p110校正的线粒体进行治疗 HD患者GABA能纹状体神经元的形态和减少突起丢失和细胞死亡 诱导多能干细胞(HD-iPS细胞)。此外，使用无偏见的蛋白质组学分析，我们最近分析了 HD患者iPS细胞来源的神经元培养中Drp1的相互作用组。我们的初步研究 鉴定了两个机制上不同的候选蛋白(线粒体AAA-ATPase成员ATADA3 家族，以及丝氨酸/苏氨酸激酶MAPK1)，参与DRp1介导的神经元损伤。这些 一系列证据表明，Drp1过度激活是HD神经退行性变的主要原因。因此， 我们假设，抑制Drp1介导的线粒体损伤是一种新的减少 体外和体内HD模型的神经病理学研究。使用生化、成像、生物能量、蛋白质组学和 从动物到患者神经元的各种药理学方法，我们在这一应用中的目标是解开 DRP1介导的线粒体功能障碍在神经退行性变中的复杂性 治疗细节。这项拟议的研究将提供有关DRp1介导的作用的新信息 线粒体分裂在HD发病机制中的作用并为研究提供了有用的模型系统 纹状体神经元的线粒体病理学。我们还将开发抑制HD的药理工具 发病机制是开发HD新疗法的第一步。