RECEPTOR GENE TRANSCRIPTION IN HUNTINGTONS DISEASE

亨廷顿病中的受体基因转录

• 批准号: 6529239
• 负责人: JANG-HO J CHA
• 金额: $ 44.4万
• 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 2003-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6529239
• 关键词: Huntington's disease; clinical research; disease /disorder model; dopamine receptor; gene mutation; genetic transcription; genetically modified animals; glutamate receptor; human tissue; immunocytochemistry; inclusion body; laboratory mouse; nucleic acid repetitive sequence; purinergic receptor; receptor expression

DESCRIPTION: (Verbatim from the Applicant's Abstract) Recently Huntington's disease (HD) and other triplet repeat disorders were found to be caused by expansions in the length of CAG codon repeat stretches in the mutated genes and mice transgenic for these mutations were created. The deleterious, biochemical consequences of this type of mutation remain unknown. Any clues to the biochemical effects of the mutation may, therefore, be vital clues to the toxic consequences of the mutation. We have found striking changes in dopamine D1 and D2, adenosine A2a and metabotropic glutamate type 2 receptor mRNA expression in three strains of mice transgenic for exon 1 of the HD gene with increased polyglutamines. The observed changes in receptor mRNA suggest that the truncated HD protein alters gene transcription. Few other biochemical changes have been found in HD transgenic mice. As such, it is one of the very few clues we can use to determine the pathologic mechanism of the disease. While receptor changes may themselves not cause disease, our data strongly suggest that receptor changes reflect a crucial, deleterious process which may include dysregulation of gene expression. Further, the magnitude of the change we have found (up to 90% decrease in presymptomatic mice) provides a strong readout that can be used in mechanistic and therapeutic studies. We will determine the generalizability and validity of these changes by measuring the levels of mRNA and protein expression for these receptors and control receptors in identified neuronal types of cortex, striatum, hippocampus and cerebellum in HD transgenic and littermate control mice as well as post-mortem presymptomatic HD and control human brains using techniques we have developed over the last 15 years; double label isotopic and nonisotopic in situ hybridization, immunoblotting, ligand binding assays and immuno-cytochemistry. We also will determine the relationship of the changes to the development of the neuronal intranuclear inclusions. (NII) that have been seen in both these mice and in human HD, whether they occur in cultured cells transfected with the mutant HD gene and the degree to which receptor changes correlate with CAG repeat number in human, mouse and cultured cells.

描述：（逐字来自申请人的摘要）最近，亨廷顿的 疾病（HD）和其他三联体重复序列疾病被发现是由以下原因引起的： 突变基因中CAG密码子重复序列长度的扩增， 产生了这些突变的转基因小鼠。有害的，生化的 这种突变的后果仍然未知。有什么线索 因此，突变的生化效应可能是毒性的重要线索。 突变的后果。我们已经发现多巴胺D1和多巴胺D2的显著变化。 D2、腺苷A2 a和代谢型谷氨酸2型受体mRNA表达 HD基因外显子1转基因的三个品系的小鼠， 聚谷氨酰胺。观察到的受体mRNA的变化表明， 截短的HD蛋白改变基因转录。很少有其他生化变化 已经在HD转基因小鼠中发现。因此，这是极少数线索之一 我们可以用来确定疾病的病理机制。While受体 变化本身可能不会引起疾病，我们的数据强烈表明， 受体的变化反映了一个关键的，有害的过程，可能包括 基因表达失调。此外，我们所拥有的变化的幅度 发现（在前驱小鼠中减少高达90%）提供了强有力的读数 可以用于机制和治疗研究。康贝特人将以 这些变化的普遍性和有效性，通过测量mRNA的水平 这些受体和对照受体的蛋白质表达， HD转基因小鼠皮层、纹状体、海马和小脑的神经元类型 和同窝对照小鼠以及死后症状前HD和 利用我们在过去15年中开发的技术控制人类大脑; 双标记同位素和非同位素原位杂交，免疫印迹， 配体结合测定和免疫细胞化学。我们还将确定 核内神经元发育与这些变化的关系 内含物。(NII)在这些小鼠和人类亨廷顿氏病中都能看到， 它们是否发生在用突变HD基因转染的培养细胞中， 受体变化与人类CAG重复数相关的程度， 小鼠和培养的细胞。