Synaptic signaling in a human stem cell model of Angelman syndrome

天使综合征人类干细胞模型中的突触信号传导

基本信息

批准号：
8415874
负责人：
Eric S Levine
金额：
$ 22.29万
依托单位：
UNIVERSITY OF CONNECTICUT SCH OF MED/DNT
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-04-01 至 2016-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8415874
关键词：
Action Potentials Address Affect Age Alleles Angelman Syndrome Animal Model Autistic Disorder Basic Science Behavioral Brain Calcium/calmodulin-dependent protein kinase Cell Culture Techniques Cell Line Cell model Cells Chromosome Deletion Complex Defect Dendritic Spines Dermal Development Disease Excitatory Synapse Fibroblasts Genes Genetic Genetically Engineered Mouse Genomics Genotype Human Immediate-Early Genes Impaired cognition Impairment In Vitro Individual Intellectual functioning disability Language Measures Mediating Modeling Molecular Motor Ataxias Movement Disorders Neurons Patients Pattern Phenotype Physiological Play Property Regulation Research Role Sampling Seizures Signal Transduction Somatic Cell Speech Synapses Synaptic Transmission Synaptic plasticity Syndrome Testing Therapeutic Tissues Ubiquitin-Protein Ligase Complexes base calmodulin-dependent protein kinase II density developmental disease disease phenotype drug discovery ephexin human disease human stem cells human tissue imprint induced pluripotent stem cell loss of function neurogenetics neuronal excitability new therapeutic target novel receptor relating to nervous system research study response screening synaptic function ubiquitin-protein ligase voltage

项目摘要

DESCRIPTION (provided by applicant): Individuals with a deletion of chromosome 15q11-q13 suffer from Angelman syndrome (AS), a neurogenetic developmental disorder characterized by intellectual disability, motor ataxia, absent speech, and seizures. The specific gene that is responsible for AS encodes the ubiquitin protein ligase UBE3A. In AS, deficits in synaptic signaling and plasticity appear to play a critical role in the disease phenotype, but the exact functional role of UBE3A and its relevant downstream targets are unknown. In order to develop appropriate treatments for AS, it is necessary to understand the pathophysiological changes caused by UBE3A deletion. Until recently it has not been possible to examine the functional properties of brain neurons in affected individuals. The discovery of genomic reprogramming of human somatic cells into induced pluripotent stem cell (iPSC) lines provides a novel way to model human diseases with complex genetics. We have recently succeeded in reprogramming dermal fibroblasts from AS patients, as well as age-matched control subjects, into iPSCs, and then differentiated these cells into functional neurons that maintain the imprinting phenotype of UBE3A expression seen in AS patients. We are now poised to take advantage of these novel patient-derived cell lines to test specific hypotheses about the underlying physiological defects in AS. The first aim uses electrophysiological and immunocytochemical approaches to explore the intrinsic functional properties of iPSC-derived neurons and activity-dependent plasticity of synaptic connections. Rescue experiments will focus on the roles of the immediate early gene ARC and the calcium/calmodulin-dependent protein kinase CaMKII in AS-associated deficits in synaptic signaling. The second aim will explore changes in synapse number and dendritic spine density in AS-derived neurons. Rescue experiments will target the role of ephexin-5, a substrate of UBE3A that plays a role in regulating excitatory synapse number during development. Overall, this approach may prove useful for identifying novel targets for drug discovery and for screening potential therapeutics aimed at ameliorating and/or curing the seizures, movement disorders, and language and cognitive impairments in Angelman syndrome.

描述（由申请人提供）：染色体 15q11-q13 缺失的个体患有天使综合征 (AS)，这是一种神经遗传性发育障碍，其特征为智力障碍、运动性共济失调、失语和癫痫发作。具体的基因是负责 AS 编码泛素蛋白连接酶 UBE3A。在 AS 中，突触信号传导和可塑性的缺陷似乎在疾病表型中发挥着关键作用，但 UBE3A 及其相关下游靶标的确切功能作用尚不清楚。为了开发出适合AS的治疗方法，有必要了解UBE3A缺失引起的病理生理变化。直到最近，还不可能检查受影响个体的大脑神经元的功能特性。将人类体细胞基因组重编程为诱导多能干细胞（iPSC）系的发现，为模拟具有复杂遗传学的人类疾病提供了一种新方法。我们最近成功地将 AS 患者以及年龄匹配的对照受试者的真皮成纤维细胞重编程为 iPSC，然后将这些细胞分化为功能性神经元维持 AS 患者中所见的 UBE3A 表达印记表型。我们现在准备利用这些新型患者来源的细胞系来测试有关 AS 潜在生理缺陷的具体假设。第一个目标是使用电生理学和免疫细胞化学方法来探索 iPSC 衍生神经元的内在功能特性和突触连接的活动依赖性可塑性。拯救实验将重点关注立即早期基因 ARC 和钙/钙调蛋白依赖性蛋白激酶 CaMKII 在 AS 相关突触信号传导缺陷中的作用。第二个目标是探索 AS 衍生神经元中突触数量和树突棘密度的变化。救援实验将针对 ephexin-5 的作用，ephexin-5 是 UBE3A 的底物，在发育过程中调节兴奋性突触数量。总体而言，这种方法可能有助于确定药物发现的新靶点以及筛选旨在改善和/或治愈天使综合征中的癫痫发作、运动障碍以及语言和认知障碍的潜在疗法。