Modulation of Caspase Pathways in Huntington's Disease

亨廷顿病中 Caspase 通路的调节

• 批准号: 8259760
• 负责人: Robert M. Friedlander
• 金额: $ 37.78万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-01-01 至 2015-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8259760
• 关键词: Address; Affect; Amino Acids; Animals; Apoptotic; Applications Grants; Binding; Body Weight; Brain; Carrier Proteins; Caspase; Caspase-1; Cell Death; Cell Line; Cell Nucleus; Cell model; Cells; Cellular Stress; Cessation of life; Collaborations; Complex; Corpus striatum structure; Cytoplasm; Data; Development; Disease; Disease Progression; Ectoderm; Embryo; Enzymes; Epigenetic Process; Event; Functional disorder; Gene Expression Regulation; Genes; Genetic; Health; Histone H3; Histones; Human; Huntington Disease; In Vitro; Investigation; Knockout Mice; Lead; Lysine; Mass Spectrum Analysis; Measurement; Measures; Mediating; Methods; Methyltransferase; Modification; Molecular; Molecular Biology; Molecular and Cellular Biology; Mus; Mutate; Nerve Degeneration; Neurons; Nuclear; Nuclear Translocation; Onset of illness; Pathogenesis; Pathology; Pathway interactions; Patients; Physiological; Play; Polycomb; Post-Translational Protein Processing; Process; Protein Family; Proteins; Regulation; Relative (related person); Role; Sampling; Signal Pathway; Structure; Testing; Time; Transcriptional Regulation; Transgenic Mice; Ubiquitin; brain tissue; enzyme activity; human Huntingtin protein; interest; mortality; motor control; mouse model; multicatalytic endopeptidase complex; mutant; neuron loss; neuropathology; novel; nucleocytoplasmic transport; overexpression; procaspase-1; research study; trend

DESCRIPTION (provided by applicant): This grant proposal addresses the role of Rip2 in Huntington's disease (HD) pathology. Rip2 modulates a number of activities of relevance to disease pathogenesis in HD. Rip2 activates caspase-1, as well as regulates a number of other critical intracellular signaling pathways. By analyzing brains from R6/2 transgenic mice that model HD, we showed that levels of Rip2 increase progressively as the animals' condition worsens. We observed parallel trends in post mortem brain samples from patients with increasingly advanced HD. In Specific Aim 1, we will repeat our experiments using YAC128 mice, animals expressing the entire mutant human HD gene and not just a fragment thereof. Besides determining the time course of Rip2 expression, we will investigate consequent changes in the molecular and cellular biology of HD mice. Measurements of the enzyme activity of caspases and the posttranslational modifications of Bcl-2-family proteins will be compared between HD mice and HD mice in which the Rip2 gene has been ablated. Finally, we will measure disease endpoints, i.e., body weight, motor control, time of disease onset, and mortality, during the course of neurodegeneration. Specific Aims 2 and 3 more directly investigate the molecular mechanism by which Rip2 protein modulates neuronal cell death. Aim 2 concerns changes in Rip2 protein's intracellular localization consequent upon its posttranslational modification by small ubiquitin-like modifier (SUMO). We will measure the relative extent of sumoylation of Rip2 from nuclear and cytoplasmic fractions of HD and healthy brain tissue. Using mass spectrometry, we will identify the specific amino acid residues within Rip2 which become sumoylated. We will mutate these residues to determine if sumoylation is required for nuclear localization of Rip2 and mutant Htt-mediated cell death. Aim 3 concerns the role of Rip2 in the epigenetic gene regulation in HD. We will study the regulation of epigenetic pathways as a putative mechanism by which Rip2 affects HD. Finally, we will determine if posttranslational modification of Rip2 is required for epigenetic gene regulation and subsequent neuronal death in HD using HD mice lacking expression of Rip2. PUBLIC HEALTH RELEVANCE: Our experimental agenda investigates several molecular pathways that modulate the rate at which Huntington's disease progresses. We are most interested in caspase-1, an enzyme that stimulates neuronal death during HD. We will use methods of mouse genetics and molecular biology to determine what proteins modulate caspase-1, what molecular events ensue from its activation, and how these physiological changes affect HD.

描述（由申请人提供）：该赠款提案涉及RIP2在亨廷顿氏病（HD）病理学中的作用。 RIP2调节了许多与HD中疾病发病机理相关的活动。 RIP2激活caspase-1，并调节许多其他关键的细胞内信号通路。通过分析HD模型的R6/2转基因小鼠的大脑，我们表明RIP2水平随着动物状况恶化而逐渐增加。我们观察到来自越来越晚期HD患者的验尸脑样品的平行趋势。在特定目标1中，我们将使用YAC128小鼠，表达整个突变体HD基因的动物重复实验，而不仅仅是其片段。除了确定RIP2表达的时间过程外，我们还将研究HD小鼠的分子和细胞生物学的随之而来的变化。在HD小鼠和RIP2基因的HD小鼠之间，将比较胱天蛋白酶的酶活性和Bcl-2-家庭蛋白的翻译后修饰的测量。最后，我们将在神经变性过程中测量疾病终点，即体重，运动控制，疾病发作时间和死亡率。具体目的2和3更直接地研究了RIP2蛋白调节神经元细胞死亡的分子机制。 AIM 2关注RIP2蛋白质内细胞内定位的变化，导致其通过小型泛素样修饰剂（SUMO）进行翻译后修饰。我们将测量来自HD和健康脑组织的RIP2 Sumoylation的相对程度。使用质谱法，我们将确定RIP2中的特定氨基酸残基。我们将突变这些残基，以确定RIP2和突变HTT介导的细胞死亡的核定位是否需要Sumoylation。 AIM 3涉及RIP2在HD表观遗传基因调控中的作用。我们将研究表观遗传途径的调节，作为RIP2影响HD的推定机制。最后，我们将使用缺乏RIP2表达的HD小鼠来确定RIP2的翻译后修饰和随后在HD中的神经元死亡所必需的。 公共卫生相关性：我们的实验议程研究了几种分子途径，这些途径调节了亨廷顿氏病的发展速度。我们对caspase-1最感兴趣，caspase-1是一种刺激HD期间神经元死亡的酶。我们将使用小鼠遗传学和分子生物学方法来确定哪些蛋白质调节caspase-1，从激活中产生的分子事件以及这些生理变化如何影响HD。