ERAD genes that suppress neurodegeneration

抑制神经退行性变的 ERAD 基因

• 批准号: 8821999
• 负责人: Robert G Kalb
• 金额: $ 25.2万
• 依托单位: CHILDREN'S HOSP OF PHILADELPHIA
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8821999
• 关键词: Adult; Alleles; Amyotrophic Lateral Sclerosis; Animals; Binding; Biological Models; Caenorhabditis elegans; Cells; Cessation of life; Complement; Cycloheximide; DNA-Binding Proteins; Degradation Pathway; Endoplasmic Reticulum; Endoplasmic Reticulum Degradation Pathway; Equilibrium; Event; Excision; Family; Frontotemporal Dementia; Functional disorder; Gene Expression; Genes; Genetic; Hand; Homeostasis; Individual; Intervention; Lead; Libraries; Locomotion; Maps; Modeling; Molecular; Molecular Chaperones; Molecular Weight; Mutation; Nerve Degeneration; Nervous system structure; Neurodegenerative Disorders; Neuronal Dysfunction; Neurons; Pathway interactions; Phenotype; Physiologic pulse; Production; Protein Biosynthesis; Proteins; Proteome; RNA Interference; Rest; Shapes; Solubility; Staging; Stress; Superoxide Dismutase; System; Testing; Toxic Actions; Toxic effect; Transgenes; Transgenic Animals; Ubiquitin; Work; Yeasts; combat; conformer; coping mechanism; endoplasmic reticulum stress; feeding; genetic manipulation; insight; loss of function; multicatalytic endopeptidase complex; mutant; neurotoxicity; novel; protein aggregate; protein degradation; protein misfolding; public health relevance; research study; response; screening; tissue culture

DESCRIPTION (provided by applicant): Protein homeostasis is a state of dynamic equilibrium in which protein production and proper folding is balanced against the protein degradation pathways such that the proteome enables cells to function normally. The accumulation of misfolded, aggregated proteins in neurodegenerative diseases is evidence for stress in the protein homeostasis dynamic and this can lead to cell dysfunction and death. One mechanism for coping with the accumulation of misfolded proteins in the endoplasmic reticulum (ER) is ER associated degradation (ERAD). The ERAD system is composed of an intricate assembly of positive and negative regulators that control the flow of substrates into the ubiquitin-proteosome pathway. Several lines of evidence implicate abnormalities in ERAD as pathophysiological contributors to neuronal dysfunction and death in models of neurodegenerative disease. I hypothesize that loss of function of select components of the ERAD pathway will suppress the toxic actions of mutant proteins such as superoxide dismutase (SOD1) or TAR DNA binding protein of 43 kDa molecular weight (TDP43). In specific aim #1, I will use C. elegans models of mutant SOD and mutant TDP43 toxicity to undertake a directed screen of ERAD components that modify toxicity. Genes will be interrogated using genetic nulls, multiple alleles when possible and nervous system specific RNAi. In Preliminary studies we have found that null alleles of two ERAD genes suppress mutant SOD or mutant TDP43 phenotypes. The strongest suppressor of toxicity was rad-23 and in specific aim #2 we will determine the molecular mechanism by which reduction of rad23 suppresses the toxicity of mutant SOD and mutant TDP43 in a mammalian tissue culture model system. I will test the hypothesis that loss of rad23A accelerates the degradation of misfolded proteins. Together these studies will identify new targets and pathways for intervention to combat neurodegenerative disease.

描述（由申请人提供）：蛋白质稳态是一种动态平衡状态，其中蛋白质产生和正确折叠与蛋白质降解途径保持平衡，使得蛋白质组使细胞能够正常发挥功能。神经退行性疾病中错误折叠、聚集的蛋白质的积累是蛋白质稳态动态应激的证据，这可能导致细胞功能障碍和死亡。应对内质网 (ER) 中错误折叠蛋白积累的一种机制是 ER 相关降解 (ERAD)。 ERAD 系统由正负调节因子的复杂组件组成，这些调节因子控制底物流入泛素-蛋白酶体途径。多项证据表明 ERAD 异常是神经退行性疾病模型中神经元功能障碍和死亡的病理生理学因素。我假设 ERAD 通路中特定成分的功能丧失将抑制突变蛋白的毒性作用，例如超氧化物歧化酶 (SOD1) 或分子量为 43 kDa 的 TAR DNA 结合蛋白 (TDP43)。在具体目标#1中，我将使用突变型 SOD 和突变型 TDP43 毒性的线虫模型来对改变毒性的 ERAD 成分进行定向筛选。将使用基因无效、多个等位基因（如果可能）和神经系统特异性 RNAi 来询问基因。在初步研究中，我们发现两个 ERAD 基因的无效等位基因抑制突变型 SOD 或突变型 TDP43 表型。最强的毒性抑制剂是 rad-23，在具体目标#2 中，我们将确定在哺乳动物组织培养模型系统中减少 rad23 抑制突变型 SOD 和突变型 TDP43 毒性的分子机制。我将检验以下假设：rad23A 的丢失会加速错误折叠蛋白质的降解。这些研究将共同​​确定对抗神经退行性疾病的干预新目标和途径。