Contribution of BIN1 and Synj1 to endosomal pathogenesis Alzheimer's Disease and Down Syndrome

BIN1 和 Synj1 对阿尔茨海默病和唐氏综合症内体发病机制的贡献

基本信息

批准号：
9904807
负责人：
Laura Beth Johnson McIntire
金额：
$ 40.5万
依托单位：
COLUMBIA UNIVERSITY HEALTH SCIENCES
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-06-15 至 2021-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9904807
关键词：
Affect Age Age of Onset Alleles Alzheimer&apos s Disease Alzheimer&apos s disease model Alzheimer&apos s disease risk Amyloid beta-Protein Amyloid beta-Protein Precursor Attention BIN1 gene Behavioral Binding Bioinformatics Brain CRISPR/Cas technology Cell model Characteristics Chromosomes, Human, Pair 21 Clathrin Clathrin Adaptors Clinical Trials Complex Data Databases Development Diploidy Disease Disease model Down Syndrome Electrophysiology (science)Endocytosis Endosomes Enzymes Functional disorder Future Gene Expression Gene Fusion Genes Genetic Genetic Polymorphism Human Impaired cognition Individual Kinetics Knock-out Late Onset Alzheimer Disease Lead Lipids Maintenance Mediating Morphology Neighborhoods Nerve Degeneration Neuroglia Neuronal Differentiation Neurons Odds Ratio Pathogenesis Pathogenicity Pathologic Pathology Pathway interactions Patients Phenotype Phosphatidylinositol 4,5-Diphosphate Phosphatidylinositols Phosphoric Monoester Hydrolases Phosphotransferases Plasma Play Population Production Prosencephalon Protein Family Proteins Reporting Risk Role Signal Transduction Single Nucleotide Polymorphism Synapses Testing Trisomy Validation Vertebral column Viral Work amphiphysin amyloid precursor protein processing cellular targeting disease phenotype fusion gene genetic variant genome wide association study global health high risk improved induced pluripotent stem cell knock-down lipid metabolism member mouse model novel overexpression prevent prophylactic remediation risk variant small hairpin RNA synaptic function synaptojanin text searching therapeutic development trafficking transcriptome sequencing

项目摘要

Alzheimer's disease is predicted to be one of the highest priority global health risks in coming decades, yet there are currently no effective prophylactic or disease modifying therapies. The primary focus in the field has been to target reduction of the synaptotoxic amyloid β-peptide (Aβ) however, recent late-stage clinical trials have proven disappointing. Therefore, new strategies and cellular targets are required. Recent work has found that genetic variants of genes involved in endocytosis such as Bridging Integrator 1 (BIN1 or amphiphysin 2/AMPH2) and phosphatidylinositol-binding clathrin assembly protein (PICALM) correlate with AD risk. Using bioinformatics analysis of STRING Consortium, gene neighborhood, gene fusions, gene co-occurrence, co- expression, experimental data, databases, text mining and protein homology indicate BIN1 is predicted to interact functionally with PICALM and critically, Synaptojanin1 (Synj1). Synj1 is a lipid phosphatase enriched in brain which dephosphorylates the critical signaling lipid phosphatidylinositol-4,5-bisphosphate [P(4,5)P2]. Phosphoinositides, known to be critical for neuronal function, have been shown by our group and others to be altered in AD affected patient brain as well as in mouse models. Synj1 is central to PI(4,5)P2 maintenance at the synapse and we have shown that loss of one copy of Synj1 has been shown to abrogate Aβ-induced synaptic dysfunction. AD and DS show similar pathologies in which APP processing and Aβ is central. DS individuals are trisomic for APP and Synj1, and Synj1 regulatory kinase DYRK1A and are at high-risk for developing AD. Synj1 has been shown to modify endosomal dysfunction in DS mouse models. Current studies have determined that iPSC derived neurons from DS individuals share similar pathogenic hallmarks of AD including increased Aβ42 production and decreased Aβ40:Aβ42 ratio. However, neuronal differentiation displayed normal neuronal conversion kinetics though one study observed exaggerated glia production, a phenotype associated with DS. Therefore, we hypothesize that Synj1 may be central to modifying synaptic and endosomal pathologies in AD and DS. We will test the hypothesis that aberrant Synj1 expression and function in neuronal phenotypes can recapitulate endosomal dysfunction in human induced pluripotent stem cell (iPSC) derived neurons. iPSC from sporadic AD and DS will be differentiated into forebrain neurons. Phenotypes shown to be mediated by Synj1 will be recapitulated in functional human neurons including endosome morphology and function, spine morphology, lipid dysregulation and functional complex formation with BIN1, PICALM, and Dyrk1a. CRISPR/Cas9 will be used to knock-out Synj1 alleles in AD and DS trisomic lines to determine necessity of Synj1 for aberrant phenotypes. Further, it is highly likely that novel cellular targets will emerge from corresponding lipidomic and RNAseq studies of functional iPSC derived neurons. We will also develop critical human neuronal cell models amenable to future therapeutic development.

阿尔茨海默病预计将成为未来几十年最重要的全球健康风险之一目前尚无有效的预防或疾病缓解疗法。该领域的主要焦点是。然而，最近的后期临床试验一直以减少突触毒性淀粉样β-肽（Aβ）为目标事实证明令人失望，因此需要新的策略和细胞目标。参与内吞作用的基因的遗传变异，例如桥接整合器 1（BIN1 或两栖蛋白） 2/AMPH2) 和磷脂酰肌醇结合网格蛋白组装蛋白 (PICALM) 与 AD 风险相关。 STRING Consortium 的生物信息学分析、基因邻域、基因融合、基因共现、共生表达、实验数据、数据库、文本挖掘和蛋白质同源性表明 BIN1 预计 Synaptojanin1 (Synj1) 与 PICALM 具有功能性相互作用，关键是 Synaptojanin1 (Synj1) 是一种富含 PICALM 的脂质磷酸酶。使关键信号脂质磷脂酰肌醇-4,5-二磷酸[P(4,5)P2]去磷酸化的大脑。众所周知，磷酸肌醇对神经元功能至关重要，我们的团队和其他人已证明它是在 AD 患者大脑以及小鼠模型中，Synj1 的改变对于 PI(4,5)P2 的维持至关重要。我们已经证明，丢失一份 Synj1 可以消除 Aβ 诱导的突触 AD 和 DS 表现出相似的病理，其中 APP 处理和 Aβ 是核心。个体对于 APP 和 Synj1 以及 Synj1 调节激酶 DYRK1A 具有三体性，并且具有以下风险：目前的研究表明，Synj1 可以改善 DS 小鼠模型的内体功能障碍。已确定来自 DS 个体的 iPSC 衍生神经元具有相似的 AD 致病特征包括 Aβ42 产量增加和 Aβ40:Aβ42 比率降低，但神经元分化。尽管一项研究观察到神经胶质细胞过度生成，但显示出正常的神经元转换动力学，因此，我们认为 Synj1 可能是修饰突触和突触的核心。我们将检验 Synj1 表达和功能异常的假设。神经元表型中的基因可以重现人诱导多能干细胞（iPSC）的内体功能障碍来自散发性 AD 和 DS 的 iPSC 将分化为前脑神经元。被证明是由 Synj1 介导的将在功能性人类神经元（包括内体）中重演形态和功能、脊柱形态、脂质失调和与 BIN1 的功能复合物形成， PICALM 和 Dyrk1a 将用于敲除 AD 和 DS 三体系中的 Synj1 等位基因，以实现确定 Synj1 对异常表型的必要性此外，新的细胞靶标很可能会出现。我们还将从功能性 iPSC 衍生神经元的相应脂质组学和 RNAseq 研究中得出结论。开发适合未来治疗发展的关键人类神经细胞模型。