Neurobiological Mechanism of 15q11-13 Duplication Autism Spectrum Disorder

15q11-13重复自闭症谱系障碍的神经生物学机制

基本信息

批准号：
9128069
负责人：
MATTHEW P ANDERSON
金额：
$ 38.06万
依托单位：
BETH ISRAEL DEACONESS MEDICAL CENTER
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：
2012-09-01 至 2018-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9128069
关键词：
15q Affect Alleles Angelman Syndrome Antibodies Ataxia Autistic Disorder Behavior Behavior Disorders Behavioral Binding Sites Brain Cell Line Cell Nucleus Cells Central Nervous System Diseases Cerebellum Cerebral cortex ChIP-seq Child Chromosomes, Human, Pair 15 Cognitive deficits Communication Consensus Copy Number Polymorphism Defect Disease Dose Electrophysiology (science)Epilepsy Epitopes Estrogen Receptors Functional disorder Gene Dosage Gene Expression Gene Mutation Genes Genetic Genetic Models Genotype Glucocorticoid Receptor Glutamates Grant Heterogeneity Human Immunofluorescence Immunologic Impairment In Situ In Vitro Inherited Isodicentric Chromosome Knock-out Learning Length Life Ligase Messenger RNA Methods Mission Modeling Molecular Morphology Mothers Motor Mus Mutation Neurobiology Neuroglia Neurons Nuclear Nuclear Export Nuclear Receptors Patients Personality Phenotype Proteins Regulation Reverse Transcriptase Polymerase Chain Reaction Role Sensory Signal Transduction Slice Social Interaction Substrate Specificity Synapses Testing Transcript Transgenes Transgenic Mice Transgenic Organisms Triad Acrylic Resin Ubiquitin Variant autism spectrum disorder brain circuitry cell type cofactor design disability dosage gamma-Aminobutyric Acid genome-wide analysis insight mRNA Expression mouse model nervous system disorder neurobiological mechanism novel overexpression promoter protein degradation reconstitution repetitive behavior response selective expression synaptic function therapeutic target therapy development tool trait transcriptome sequencing ubiquitin ligase ubiquitin-protein ligase

项目摘要

DESCRIPTION (provided by applicant): The long-term objective of this project is to compare and contrast the defects in neuronal mRNA expression and circuit functions produced by altered Ube3a gene dosage that may underlie the behavioral phenotypes of Autism Spectrum Disorder (ASD) with maternal 15q11-13 duplication and Angelman's Syndrome (AS). Cells from 15q11-13 ASD and AS patients have excess and deficient E3 ubiquitin ligase, Ube3a, respectively. Ube3a is the sole gene expressed selectively from the maternal allele in brain. The majority of children who inherit 15q11-13 duplications from their mothers develop ASD and the more copies inherited, the more severe the impairment. Recently, we established that increasing Ube3a gene dosage alone reconstitutes the triad of autism-related behavioral deficits in mice. Angelman's Syndrome (AS), by contrast, results when children inherit maternal Ube3a gene mutations. Importantly, Ube3a also acts as a nuclear receptor co-activator regulating gene expression independent of ligase activity. Thus we hypothesized that excess Ube3a (15q dup model) acts in the nucleus to perturb the normal expression of specific neuronal genes and encoded proteins to alter circuit function and thereby generate autism-related behavioral deficits. The logical corollary is that deficiencies of nuclear Ube3a may alter gene expression to change circuit function and produce Angelman-related behavioral deficits through the same, but opposite mechanisms. Because the brain's circuitries are designed for quantitative assessment of sensory information and quantitative motor responses, it is likely that many molecules controlling circuit functions can cause graded changes in behavior when their quantities are altered. We propose Ube3a do so through a dose-dependent regulation of neuronal gene expression. Such molecular quantity variations likely underlie the intrinsic heterogeneity of behavioral disorders like ASD. The specific aims of this R01 grant follow: (1 and 2) determine if Ube3a gene dosage causes ASD (excess Ube3a) and AS (deficient Ube3a) related behavioral deficits through its actions within the nucleus; (3) identify the cortical neuron mRNAs quantitatively regulated by excesses or deficiencies of Ube3a; and (4) identify the cortical circui dysfunctions quantitatively induced by excesses and deficiencies of Ube3a. Our methods include a novel nuclear-targeted Ube3a transgene, a neuron cell-type specific expression of Ube3a, genome wide analysis of transcripts, and identification of consensus Ube3a-gene promoter binding sites. Slice electrophysiology and neuronal morphology will examine the effects of global and cell-type specific changes and nuclear targeted changes of Ube3a gene dosage on cortical circuit function in living brain slices. This analysis will facilitate our effors to bridge from genes to circuits to behavior in the two contrasting human neurological diseases. The project promotes the agency's mission to further a deeper understanding of the neuronal cells, circuits, and genes involved in ASD and AS via genetic models. The novel molecular insights and genetic tools will facilitate development of treatments for these life-long behavioral disabilities.

描述（由申请人提供）：该项目的长期目标是比较和对比 Ube3a 基因剂量改变所产生的神经元 mRNA 表达和回路功能缺陷，这些缺陷可能是自闭症谱系障碍 (ASD) 行为表型的基础15q11-13 重复和天使综合征 (AS)。来自 15q11-13 ASD 和 AS 患者的细胞分别具有过量和缺陷的 E3 泛素连接酶 Ube3a。 Ube3a 是大脑中母体等位基因选择性表达的唯一基因。大多数从母亲那里遗传 15q11-13 重复的孩子都会患上自闭症谱系障碍 (ASD)，遗传的拷贝越多，损伤就越严重。最近，我们确定仅增加 Ube3a 基因剂量即可重建小鼠自闭症相关行为缺陷的三联征。相比之下，当儿童遗传了母体 Ube3a 基因突变时，就会导致天使综合症 (AS)。重要的是，Ube3a 还充当核受体共激活剂，独立于连接酶活性调节基因表达。因此，我们假设过量的 Ube3a（15q dup 模型）在细胞核中起作用，扰乱特定神经元基因和编码蛋白质的正常表达，从而改变回路功能，从而产生与自闭症相关的行为缺陷。逻辑推论是，核 Ube3a 的缺陷可能会改变基因表达，从而改变回路功能，并通过相同但相反的机制产生与 Angelman 相关的行为缺陷。由于大脑的电路是为了定量评估感觉信息和定量运动反应而设计的，因此许多控制电路功能的分子在其数量改变时可能会导致行为的分级变化。我们建议 Ube3a 通过神经元基因表达的剂量依赖性调节来实现这一点。这种分子数量的变化可能是自闭症等行为障碍的内在异质性的基础。该 R01 资助的具体目标如下：（1 和 2）确定 Ube3a 基因剂量是否通过其在细胞核内的作用导致 ASD（Ube3a 过量）和 AS（Ube3a 缺陷）相关的行为缺陷； (3)鉴定Ube3a过量或缺乏所定量调节的皮质神经元mRNA； (4)定量识别由Ube3a过量和缺乏引起的皮质循环功能障碍。我们的方法包括新型核靶向 Ube3a 转基因、Ube3a 的神经元细胞类型特异性表达、转录本的全基因组分析以及共有 Ube3a 基因启动子结合位点的鉴定。切片电生理学和神经元形态学将检查 Ube3a 基因剂量的整体和细胞类型特异性变化以及核靶向变化对活体脑切片中皮质回路功能的影响。这项分析将有助于我们努力在两种截然不同的人类神经疾病中从基因到回路再到行为之间建立桥梁。该项目推动了该机构的使命，即通过遗传模型进一步深入了解 ASD 和 AS 所涉及的神经元细胞、回路和基因。新颖的分子见解和遗传工具将促进这些终生行为的治疗方法的开发残疾。