EXCITATORY AA RECEPTORS' ROLE IN ALZHEIMER'S & OTHER NEURODEGENERATIVE DISORDERS

兴奋性 AA 受体在阿尔茨海默病中的作用

• 批准号: 3767824
• 负责人: J W KUSIAK
• 金额: --
• 依托单位: NATIONAL INSTITUTE ON AGING
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3767824
• 关键词: Alzheimer's disease; NMDA receptors; RNase protection assay; aging; gene expression; genetic promoter element; genetic regulation; glutamate receptor; laboratory rat; molecular cloning; molecular pathology; neural degeneration; neurotrophic factors; protein isoforms; receptor expression; reporter genes; tissue /cell culture; transfection

The major emphasis of this project is the discovery of the role of EAA receptors in neurodegenerative disorders of aging. This year we identified additional isoforms of the NMDAR1 receptor subunit and we measured changes in receptor mRNA isoform expression by RNase protection. We detected an approximate 20% increase in hippocampus in an isoform lacking several phosphorylation sites in the carboxyl terminal in aged rats. Mini-gene constructs of the GLUR-2 glutamate/AMPA receptor subunit were constructed and transfected into cultured cells in order to examine the mutually exclusive splicing of two exons important in regulating agonist sensitivity of this subunit. We discovered that eliminating a downstream branch point led to exon exclusion and surprisingly, use of an upstream cryptic donor site. We cloned and characterized the promoter region of the NMDAR1 receptor. We identified two major transcription start sites at nucleotides -276 and -238 upstream of codon 1. Proximal to the transcriptional start site are one GSG and two SP1 regulatory motifs but no TATA or CAAT boxes. These results suggest that the NMDAR1 receptor gene has characteristics of a housekeeping gene but may be regulated by immediate-early genes. Reporter gene constructs of this promoter region show strong positive and strong negative elements. We are currently studying the role of NGF in regulating NMDAR1 gene expression.

该项目的主要重点是发现EAA的作用 衰老的神经退行性疾病中的受体。今年我们 确定了NMDAR1受体亚基的其他同工型，我们 通过RNase测得的受体mRNA同工型表达的变化 保护。我们检测到海马大约增加了20％ 羧基缺少几个磷酸化位点的同工型 老年大鼠的末端。 Glur-2的迷你基因构建体 构建谷氨酸/AMPA受体亚基并转染 培养的细胞以检查相互排斥的剪接 两个外显子对调节该亚基的激动剂敏感性很重要。 我们发现消除下游分支点导致外显子 排除和令人惊讶的是，使用上游隐秘的供体网站。我们 克隆并表征了NMDAR1受体的启动子区域。 我们确定了核苷酸-276的两个主要转录起始位点 和-238密码子上游1。靠近转录开始 站点是一个GSG和两个SP1调节图案，但没有TATA或CAAT 盒子。这些结果表明NMDAR1受体基因具有 管家基因的特征，但可能由 直接的基因。该启动子区域的报告基因构建体 表现出强烈的正面和强大的负面因素。我们目前 研究NGF在调节NMDAR1基因表达中的作用。