A systematic test of the relation of ASD heterogeneity to synaptic function

ASD 异质性与突触功能关系的系统测试

• 批准号: 7928775
• 负责人: ROBERT C MALENKA
• 金额: $ 87.59万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-30 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7928775
• 关键词: Accounting; Acute; Address; Affect; Autistic Disorder; Biological; Biological Assay; Brain; Candidate Disease Gene; Cell Survival; Cells; Clinical; Cognition Disorders; Communication; Communities; Complex; Copy Number Polymorphism; Data; Effectiveness; Electroporation; Exhibits; Funding; Gene Deletion; Gene Duplication; Gene Mutation; Gene Silencing; Generations; Genes; Genetic; Goals; Heritability; Heterogeneity; Hippocampus (Brain); Homologous Gene; Impairment; Injection of therapeutic agent; Laboratories; Libraries; Measures; Molecular; Morphology; Mus; Mutation; Neurobiology; Neurons; Optics; Other Genetics; Pathogenesis; Pathway interactions; Patients; Phenotype; Physiological; Process; Proteins; Publications; Reagent; Role; Slice; Subfamily lentivirinae; Symptoms; Synapses; Techniques; Testing; Therapeutic Intervention; Translating; Variant; Virus; autism spectrum disorder; base; clinical phenotype; combinatorial; density; design; gain of function; in utero; in vivo; knock-down; neuron development; overexpression; public health relevance; response; small hairpin RNA; synaptic function; synaptogenesis; tool; tool development; vector; web site

DESCRIPTION (provided by applicant): Although autism spectrum disorders (ASDs) are highly heritable, ASDs are heterogeneous, and no single genetic cause contributes to ASDs in a large proportion of patients. Instead, heterogeneous genetic changes, including many single gene mutations and copy-number variations (CNVs) are found in ASDs. Thus, a key question is whether different genetic changes contribute to ASDs via multiple, independent, pathogenic pathways, or whether the various genetic changes in ASDs converge onto a single pathogenic pathway. Several independent mutations in genes encoding synaptic proteins, such as neurexin-1, neuroligins, and SHANK3, suggested that ASDs may generally involve an impairment of synaptic communication between neurons. However, most of the other genetic changes observed in ASDs have no known effect on synapses in fact, have no known effect on any brain function. Thus, the major goal of the present proposal is to conduct a large scale, systematic analysis of the synaptic effects of genetic changes in ASDs. The approach will be to over express (to mimic gene duplications) or knock down (to mimic gene inactivations) mRNAs corresponding to 81 ASD candidate genes, and to test the effect of these manipulations on synapses using standardized assays. Cell viability, neuronal development, synapse density and synapse function will be assessed in cultured mouse neurons using optical and electro-physiological assays that are well established in the PI's laboratories. Genes that were found to affect neuronal development, synapse formation, or synapse function in cultured neurons will be studied by the same manipulations in vivo after stereotaxic injection of lentiviruses into the mouse hippocampus, or after in utero electroporation. Changes in synapse function and plasticity will then be examined in acute slices from these mice using standard electrophysiological techniques well established in the PI's laboratories. All results from this project will be posted on a dedicated public website, and all reagents generated will be made readily available to the scientific community. The results of this project will provide a standardized reference point for the function of ASD candidate genes, and provide an initial test of the hypothesis that despite their clinical and genetic heterogenity, ASDs involve a common, if diverse, pathway acting on synaptic communication in the brain. PUBLIC HEALTH RELEVANCE: Autism spectrum disorders are known to be clinically and genetically heterogeneous, but it is unclear whether these two types of heterogeneity are related, and how specifically the various genetic changes affect brain function. This project will address these issues by studying the changes in neuron-to-neuron communication caused by the genes associated with autism.

描述(申请人提供)：尽管自闭症谱系障碍(ASD)具有高度的遗传性，但ASD是异质性的，在很大比例的患者中没有单一的遗传原因导致ASD。相反，在自闭症患者中发现了异质性遗传变化，包括许多单基因突变和拷贝数变异(CNV)。因此，一个关键的问题是，不同的基因变化是否通过多条独立的致病途径导致自闭症，或者自闭症的各种遗传变化是否汇聚到一条致病途径上。突触蛋白编码基因的几个独立突变，如neuresin-1、神经连接蛋白和SHANK3，表明自闭症通常可能涉及神经元之间突触通信的损害。然而，在自闭症中观察到的大多数其他基因变化对突触没有已知的影响，事实上，对任何大脑功能都没有已知的影响。因此，本提案的主要目标是对自闭症遗传变化的突触效应进行大规模、系统的分析。该方法将过度表达(模仿基因复制)或下调(模仿基因失活)对应于81个ASD候选基因的mRNAs，并使用标准化的分析方法测试这些操作对突触的影响。在培养的小鼠神经元中，细胞活力、神经元发育、突触密度和突触功能将使用PI实验室建立的光学和电生理分析进行评估。对培养的神经元中影响神经元发育、突触形成或突触功能的基因，将在小鼠海马体内立体定向注射慢病毒后，或在宫内电穿孔后，通过同样的操作在体内进行研究。然后，将使用PI实验室建立的标准电生理学技术，在这些小鼠的急性切片中检查突触功能和可塑性的变化。该项目的所有结果将在一个专门的公共网站上公布，所有产生的试剂都将随时提供给科学界。该项目的结果将为ASD候选基因的功能提供一个标准化的参照点，并对以下假设提供初步检验：尽管ASD在临床和遗传上具有异质性，但ASD涉及一条共同的、如果不同的、作用于大脑中突触通讯的途径。 公共卫生相关性：众所周知，自闭症谱系障碍在临床和遗传上是不同的，但尚不清楚这两种类型的异质性是否相关，以及各种基因变化如何具体影响大脑功能。这个项目将通过研究自闭症相关基因引起的神经元对神经元通讯的变化来解决这些问题。