RECEPTOR GENE TRANSCRIPTION IN HUNTINGTON'S DISEASE

亨廷顿病中的受体基因转录

• 批准号: 7064211
• 负责人: JANG-HO J CHA
• 金额: $ 35.57万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-12 至 2009-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7064211
• 关键词: Huntington' s disease; cell line; chromatin immunoprecipitation; clinical research; cytotoxicity; disease /disorder model; gene expression; gene mutation; genetic promoter element; genetic susceptibility; genetic transcription; genetically modified animals; histones; human tissue; laboratory mouse; messenger RNA; mitochondria; neurotransmitter metabolism; neurotransmitter receptor; pathologic process; phenotype; postmortem; protein binding; protein structure function; transcription factor

DESCRIPTION (provided by applicant): Huntington's disease is a progressive neurodegenerative disease for which no effective treatment exists. Transcriptional dysregulation is now considered to be an important mechanism in the pathogenesis of Huntington's disease (HD) and other polyglutamine diseases. Alteration of mRNA populations, including those encoding for neurotransmitter receptors, is a hallmark of murine and cellular models of HD as well as human HD. Although numerous studies have confirmed that mRNA populations are altered in HD models, the mechanism underlying such changes remains unknown. Transcription factors, including specificity protein 1 (Sp1), have been implicated in HD pathogenesis, but the role of altered Sp1 function in producing mRNA alterations has not been answered. In this application, we take advantage of a well-described set of gene alterations--those occurring in neurotransmitter receptors--as a starting point for determining the molecular mechanisms of transcriptional dysregulation. We propose a series of hypotheses that will yield critical mechanistic insight into the processes that alter mRNA populations and cause disease pathogenesis. Specific Aim 1 will test the hypothesis that mutant huntingtin selectively alters the association of Sp1 with the promoters of genes that are downregulated in HD. Chromatin Immunoprecipitation (CHIP) assays will assess the degree of Sp1-gene binding in cellular, murine and human HD tissues. Specific Aim 2 will test the hypothesis that decreased Sp1 binding to selected gene promoters causes HD phenotypes. Sp1 levels will be manipulated through RNA interference, dominant negative constructs and overexpression, and the effects of these manipulations on mRNA and cellular toxicity will be assessed. Specific Aim 3 tests the hypothesis that interference in Sp 1 function by huntingtin causes abnormal histone modification. Histone modifications will be examined in mouse and cell models of HD. Taken together, these proposed experiments will systematically address several key molecular loci of potential damage by mutant huntingtin. Such fundamental mechanistic information is critical to the eventual development of effective therapy for HD.

描述（由申请人提供）：亨廷顿病是一种进行性神经退行性疾病，目前尚无有效的治疗方法。转录失调现在被认为是亨廷顿病（HD）和其他多聚谷氨酰胺疾病发病机制的重要机制。 mRNA 群体的改变，包括编码神经递质受体的 mRNA 群体的改变，是 HD 以及人类 HD 的小鼠和细胞模型的标志。尽管大量研究已经证实 HD 模型中 mRNA 群体发生了改变，但这种变化背后的机制仍然未知。包括特异性蛋白 1 (Sp1) 在内的转录因子与 HD 发病机制有关，但 Sp1 功能改变在产生 mRNA 改变中的作用尚未得到解答。在本申请中，我们利用一组详细描述的基因改变（发生在神经递质受体中的基因改变）作为确定转录失调分子机制的起点。我们提出了一系列假设，这些假设将对改变 mRNA 群体和导致疾病发病机制的过程产生关键的机制洞察。具体目标 1 将检验突变亨廷顿蛋白选择性改变 Sp1 与 HD 中下调基因启动子的关联这一假设。染色质免疫沉淀 (CHIP) 检测将评估细胞、小鼠和人类 HD 组织中 Sp1 基因结合的程度。具体目标 2 将检验以下假设：减少 Sp1 与选定基因启动子的结合会导致 HD 表型。 Sp1 水平将通过 RNA 干扰、显性失活结构和过度表达来控制，并且将评估这些操作对 mRNA 和细胞毒性的影响。具体目标 3 检验亨廷顿蛋白干扰 Sp 1 功能会导致组蛋白修饰异常的假设。将在 HD 的小鼠和细胞模型中检查组蛋白修饰。总而言之，这些拟议的实验将系统地解决突变亨廷顿蛋白潜在损害的几个关键分子位点。这些基本机制信息对于最终开发有效的 HD 治疗方法至关重要。