Post-transcriptional gene regulation Alzheimer's Disease

转录后基因调控阿尔茨海默病

• 批准号: 7132280
• 负责人: MYRIAM none GOROSPE
• 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/7132280
• 关键词: Alzheimer' s disease; RNA binding protein; amyloid proteins; cell line; gene expression; genetic polymorphism; genetic regulation; genetic susceptibility; low density lipoprotein receptor; messenger RNA; neurogenetics; posttranscriptional RNA processing; protein purification; ribonucleoproteins; transcription factor

Mammalian cells respond to physiological and pathological cues by implementing changes in gene expression patterns. Post-transcriptional processes (RNA splicing and maturation, as well as mRNA transport, stability and translation) are increasingly recognized as being essential means of governing gene expression. Two studies are underway in the RNA Regulation Section to investigate post-transcriptional gene control in Alzheimer's Disease (AD). Through these studies, we seek to elucidate the contribution of mRNA sequences and RNA-binding proteins towards regulating the expression of critical gene products in AD pathogenesis. The first set of studies are aimed at investigating the post-transcriptional regulation of amyloid precursor protein (APP) expression. APP is a cell-surface protein whose cleavage can lead to the generation of small extracellular peptides (Abeta or amyloid-beta peptides) which are involved in AD. Amyloidogenic cells overexpress APP mRNA, which in turn enhances the production of toxic Abeta peptides leading to their accumulation and deposit in the brains of patients with AD. Given previous studies showing that APP expression is critically regulated by altered mRNA stability and protein biosynthesis, we are seeking to systematically identify the RNA-binding proteins that associate with the APP mRNA and influence their half-life and translation. Using a number of in vitro and in vivo approaches, we have began to assess the association of APP the mRNA with known RNA-binding proteins that recognize AU-rich transcripts, including HuR, AUF1, TTP, TIA-1, TIAR, KSRP, NF-90, hnRNP A1, and BRF1. We plan to use affinity purification methods to identify additional proteins that form complexes with the APP mRNA. The functional consequences of these ribonucleoprotein associations will be subsequently tested in AD-relevant cell lines. Second, we plan to investigate the influence of polymorphic noncoding sequences on the post-transcriptional regulation of AD susceptibility genes. The pathogenesis of late-onset AD is not well understood, but linkage studies have mapped critical late-onset AD susceptibility genes to a region in chromosome 12. Two genes in this chromosomal region have been postulated to participate in AD: oxidized LDL-receptor 1 (OLR1) and transcription factor LBP-1c/CP2/LSF. Given that these two genes bear 3'UTR polymorphisms, we are investigating if such alleles with polymorphic untranslated sequences are subject to differential post-transcriptional regulation.

哺乳动物细胞通过实施基因表达模式的变化来应对生理和病理线索。转录后过程（RNA剪接和成熟以及mRNA转运，稳定性和翻译）越来越被认为是控制基因表达的必不可少的手段。 RNA调节部分正在进行两项研究，以研究阿尔茨海默氏病（AD）中转录后基因的控制。通过这些研究，我们试图阐明mRNA序列和RNA结合蛋白对调节AD发病机理中关键基因产物表达的贡献。 第一组研究旨在研究淀粉样前体蛋白（APP）表达的转录后调节。 App是一种细胞表面蛋白，其切割可以导致与AD有关的小细胞外肽（Abeta或淀粉样蛋白β肽）的产生。淀粉样细胞过表达的APP mRNA，进而增强了有毒Abeta肽的产生，导致其积累并沉积在AD患者的大脑中。鉴于先前的研究表明，APP表达受mRNA稳定性和蛋白质生物合成的改变，我们正在寻求系统地识别与App mRNA相关的RNA结合蛋白并影响其半衰期和翻译。使用多种体外和体内方法，我们开始评估APP MRNA与已知的RNA结合蛋白的关联，这些蛋白可以识别包括HUR，AUF1，TTP，TIA-1，TIAR，TIAR，KSRP，NF-90，NF-90，NF-90，HNRNP A1和BRF1在内的AU-AU富集记录。我们计划使用亲和力纯化方法来鉴定与App mRNA形成复合物的其他蛋白质。这些核糖核蛋白缔约的功能后果将随后在与AD相关的细胞系中进行测试。 其次，我们计划研究多态性非编码序列对AD易感基因转录后调节的影响。晚期AD的发病机理尚不清楚，但是连锁研究已将关键的后期AD易感基因映射到12号染色体的一个区域。该染色体区域中的两个基因已被假定参与AD：氧化的LDL-LDL-RECEPTOR 1（OLR1）和转录因子LBP-1C/CP2/CP2/LSF。鉴于这两个基因具有3'UTR多态性，我们正在研究具有多态性未翻译序列的这些等位基因是否受到转录后调节的差异。