The role of CELF2 and its genetic variants in Alzheimer's disease

CELF2及其遗传变异在阿尔茨海默病中的作用

• 批准号: 10551196
• 负责人: Lizhen Chen
• 金额: $ 45.11万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-02-01 至 2026-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10551196
• 关键词: Adult; Affect; Age; Aging; Alleles; Alternative Splicing; Alzheimer' s Disease; Alzheimer' s disease brain; Alzheimer' s disease model; Alzheimer' s disease pathology; Alzheimer' s disease patient; Alzheimer' s disease risk; Animal Model; Animals; Autopsy; Behavior; Behavioral; Binding; Biochemical; Brain; Brain region; Caenorhabditis elegans; Clustered Regularly Interspaced Short Palindromic Repeats; Cognition; Data; Defect; Dementia; Deposition; Disease; Elderly; Environmental Risk Factor; Exons; Family; Genes; Genetic; Genetic Polymorphism; Genetic Screening; Genomics; Health; High-Throughput Nucleotide Sequencing; Hippocampus; Homologous Gene; Human; Human Genetics; Immunohistochemistry; Immunoprecipitation; Impaired cognition; Individual; Induced pluripotent stem cell derived neurons; Introns; Knock-in; Knock-out; Knockout Mice; Late Onset Alzheimer Disease; Learning; Longevity; MAPT gene; Mammals; Measures; Memory; Messenger RNA; Microtubules; Minor; Modeling; Mus; Mutation; Nerve Degeneration; Nervous System; Neurodegenerative Disorders; Neurons; Pathogenesis; Pathology; Patients; Phenotype; Play; Protein Isoforms; Proteins; Publishing; RNA Splicing; RNA Stability; RNA-Binding Proteins; Regulation; Reporting; Research; Risk Factors; Risk Reduction; Role; Sampling; Single Nucleotide Polymorphism; Spinal Muscular Atrophy; Tauopathies; Techniques; Testing; Tissues; Work; brain cell; calmodulin-dependent protein kinase II; cell type; comparison control; conditional knockout; crosslink; crosslinking and immunoprecipitation sequencing; experience; genetic analysis; genetic association; genetic variant; genome wide association study; hTau Mice; high risk; improved; induced pluripotent stem cell; insight; knock-down; mRNA Expression; member; mouse model; mutant; neurotoxicity; new therapeutic target; overexpression; potential biomarker; presenilin-1; presenilin-2; protective effect; protein expression; risk variant; tau Proteins; tau expression; therapeutic target; transcriptome sequencing

Age is the most important risk factor for Alzheimer's disease (AD), but the occurrence of this disease is also affected by environmental factors, individual experience and genetic pre-deposition. Genetic factors are well established to play an important role in risk of AD. CELF2, an RNA binding protein that regulates alternative splicing and RNA stability, has been recently identified as a risk factor associated with AD. Polymorphisms in CELF2 are significantly associated with high-risk alleles of APOE, and the “A” allele of SNP rs2242451 is associated with reduced AD risk. CELF2 is highly expressed in the nervous system, and enhanced neuronal CELF2 expression levels have been found in various neurodegeneration models and human patients. We generated a conditional knockout mouse Celf2 allele. Our preliminary data suggest that deleting Celf2 in adult brain has beneficial effects, including improved learning and memory. We identified mRNA targets of mouse CELF2 (using CLIP-seq; cross-linking immunoprecipitation high-throughput sequencing) and found that CELF2 binds to introns around the alternatively spliced exons of a set of AD- regulated genes, including APP, MAPT (Tau), PSEN1, PSEN2, and BIN1, suggesting a key role of CELF2 in regulating alternative splicing of AD-related genes. Alternative splicing of these AD-related genes is known to regulate AD pathogenesis. For example, alternative splicing of exon 10 of the tau mRNA gives rise to protein isoforms with three (3R) or four (4R) microtubule binding repeats. Imbalances in 4R: 3R ratio alone have been reported sufficient to induce the pathogenesis of AD in a human-Tau mouse model. Taken together with the genetic association between CELF2 SNP and reduced AD risk in humans, we hypothesize that CELF2 expression is up-regulated in AD brains and loss of CELF2 in adult brains is sufficient to rescue AD-related phenotypes. In Specific Aim 1, we will test whether loss of CELF2 can suppress AD-related phenotypes in C. elegans AD models. In Specific Aim 2, we will test whether loss of CELF2 in the adult brain is protective through regulating alternative splicing using AD mouse models. In Specific Aim 3, we will test whether CELF2 expression is increased in AD brains using postmortem human samples and ask if the AD risk-reducing SNP down regulates CELF2 expression or inhibits its function using human iPSC-derived neurons. We have obtained postmortem brain samples and established a strong research team with expertise in genetics, genomics, postmortem AD brains and iPSC. Data from the proposed work will provide important mechanistic insights that go well beyond published human genetic analyses and ultimately yield new therapeutic targets for the treatment of AD.

年龄是阿尔茨海默病（AD）最重要的危险因素，但该病的发生 还受环境因素、个人经历和遗传预沉积的影响。遗传因素是 已确定在 AD 风险中发挥重要作用。 CELF2，一种RNA结合蛋白，调节 选择性剪接和 RNA 稳定性最近被确定为与 AD 相关的危险因素。 CELF2 的多态性与 APOE 的高风险等位基因和 SNP 的“A”等位基因显着相关 rs2242451 与 AD 风险降低相关。 CELF2在神经系统中高表达，并且 在各种神经退行性变模型中发现神经元 CELF2 表达水平增强 人类患者。我们生成了条件敲除小鼠 Celf2 等位基因。我们的初步数据表明 删除成人大脑中的 Celf2 具有有益的作用，包括改善学习和记忆。我们确定了 小鼠 CELF2 的 mRNA 靶标（使用 CLIP-seq；交联免疫沉淀高通量 测序）并发现 CELF2 与一组 AD- 的可变剪接外显子周围的内含子结合 调节基因，包括 APP、MAPT (Tau)、PSEN1、PSEN2 和 BIN1，表明 CELF2 在 调节 AD 相关基因的选择性剪接。已知这些 AD 相关基因的选择性剪接 调节 AD 发病机制。例如，tau mRNA 外显子 10 的选择性剪接产生蛋白质 具有三个 (3R) 或四个 (4R) 微管结合重复序列的亚型。仅 4R：3R 比例失衡就已 据报道足以在人 Tau 小鼠模型中诱导 AD 的发病机制。与 CELF2 SNP 与人类 AD 风险降低之间的遗传关联，我们假设 CELF2 AD 大脑中的表达上调，成人大脑中 CELF2 的缺失足以挽救 AD 相关疾病 表型。在具体目标 1 中，我们将测试 CELF2 的缺失是否可以抑制线虫中与 AD 相关的表型。 线虫 AD 模型。在具体目标 2 中，我们将测试成人大脑中 CELF2 的缺失是否具有保护作用 通过使用 AD 小鼠模型调节选择性剪接。在Specific Aim 3中，我们将测试CELF2是否 使用死后人类样本，AD 大脑中的表达增加，并询问降低 AD 风险的 SNP 是否存在 使用人 iPSC 衍生的神经元下调 CELF2 表达或抑制其功能。我们有 获得死后大脑样本并建立了一支拥有遗传学专业知识的强大研究团队， 基因组学、死后 AD 大脑和 iPSC。拟议工作的数据将提供重要的机制 远远超出已发表的人类遗传分析的见解，并最终产生新的治疗靶点 AD的治疗。