VTA VGluT2 Sociability Circuit in Genetic Autism

遗传性自闭症中的 VTA VGluT2 社交回路

• 批准号: 10091988
• 负责人: CLIFFORD B SAPER
• 金额: $ 43.75万
• 依托单位: BETH ISRAEL DEACONESS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-05-01 至 2023-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10091988
• 关键词: 15q; Acute; Affect; Alleles; Back; Behavior Disorders; Behavioral; Binding; Bioinformatics; Brain; Brain Stem; Bypass; Cell Nucleus; Chromosome 15; Complex; Copy Number Polymorphism; Defect; Dopamine; Dose; Electrophysiology (science); Epilepsy; Excitatory Synapse; Gene Delivery; Gene Dosage; Gene Proteins; Genes; Genetic; Genetic Techniques; Genetic Transcription; Glutamate Receptor; Glutamates; Human; Hypothalamic structure; Impairment; Intervention; Isodicentric Chromosome; Learning; Ligands; Light; Link; Maps; Medial; Mediating; Methods; Midbrain structure; Molecular; Motivation; Mutate; Nature; Neurons; Neuropeptides; Nucleus Accumbens; Oxytocin; Oxytocin Receptor; Population; Preclinical Testing; Reporting; Seizures; Series; Signal Transduction; Site; Slice; Social Behavior; Social Interaction; Synapses; System; Techniques; Testing; Therapeutic; Treatment Efficacy; UBE3A gene; Ventral Tegmental Area; Vertebrates; Viral Vector; Virus; autism spectrum disorder; base; comorbidity; delta receptors; dosage; human model; in vivo; mouse genetics; neuronal circuitry; neurophysiology; novel; optogenetics; paraventricular nucleus; postsynaptic; preclinical study; presynaptic; programs; promoter; reconstitution; repetitive behavior; synergism; therapeutic candidate; therapeutic evaluation; therapeutic target; tool; transmission process; ubiquitin ligase

PROJECT SUMMARY Autism spectrum disorder (ASD) is characterized by its deficits in social interactions. Oxytocin is a hypothalamic neuropeptide known to increase social interactions through its oxytocin receptor (Oxtr) but where this occurs remains undefined. Maternal 15q11-13 triplications (extranumerary isodicentric chromosome 15, idic15) cause a highly penetrant autism that we have linked to the increased dosage of UBE3A. UBE3A encodes an ubiquitin-ligase and transcriptional co-regulator expressed exclusively from the maternal allele in mature neurons. Seizures are a frequent comorbidity in ASD including in idic15. In our recent study (Krishnan et al. Nature 2017), we established that a previously enigmatic population of glutamatergic neurons in the brainstem ventral tegmental area (VTA) drives sociability and found increases of UBE3A and seizures converge to repress expression of autism network gene Cbln1 to impair sociability within these neurons. In Aim 1, we investigate a new concept, that oxytocin receptors mark the specific population of VTA glutamatergic neurons that promote sociability and that oxytocin receptor activity in these neurons is necessary for normal sociability. In Aim 2, we investigate the target site where VTA glutamatergic neurons promote sociability by testing if chemogenetically-controlled activity and Grid1 expression (Cbln1's postsynaptic binding partner that is deleted in autism) in the nucleus accumbens are necessary and sufficient to promote sociability. VTA glutamatergic neurons form excitatory synapses onto nucleus accumbens neurons and we have shown these synapses are impaired by Cbln1 deletion and by seizures. In Aim 3, we test if increases of UBE3A and seizures converge on the specific VTA glutamatergic neurons that express oxytocin receptors to impair sociability and glutamategic transmission if these defects can rescued by adding back Cbln1 to these specialized neurons. In Aim 4, we investigate whether in vivo chemogenetic increases of oxytocin signaling can rescue the VTA glutamatergic neuron to nucleus accumbens synaptic defects and sociability impairments produced by increased UBE3A and seizures. In this study, we combine conditional mouse genetics, stereotaxic viral vector-based gene deliveries methods including VGluT2 and Oxtr promoter intersectional genetics, behavioral chemogenetics, and brain slice optogenetics electrophysiology techniques to uncover a convergent molecular autism gene network and neuronal circuitry where three models of human autism spectrum disorder impair sociability. (1) Increased Ube3a gene dosage (maternal 15q11-13 triplication) and (2) epilepsy convergence to repress Cbln1 in VTA glutamatergic neurons and (3) loss of Grid1, Cbln1's postsynaptic binding partner in nucleus accumbens all impair sociability. We also perform a series of in vivo preclinical tests of the efficacy of therapeutic interventions using viral vector-based methods aimed at these molecules and circuits and the oxytocin system.

项目摘要 自闭症谱系障碍（ASD）的特点是缺乏社会交往。催产素是一种 已知下丘脑神经肽通过其催产素受体（Oxtr）增加社会互动，但其中 这种情况仍然没有定义。母体15 q11 -13三倍体（即15号等双着丝粒染色体， idic 15）导致高度渗透性自闭症，我们认为这与UBE 3A剂量的增加有关。UBE3A 编码一种泛素连接酶和转录辅助调节因子，仅从母体等位基因表达， 成熟神经元癫痫发作是ASD（包括IDIC）的常见合并症15。在我们最近的研究中（Krishnan 等人，Nature 2017），我们确定了在大脑中的一个先前神秘的多巴胺能神经元群体， 脑干腹侧被盖区（VTA）驱动社交，并发现UBE 3A和癫痫发作的增加 收敛到抑制自闭症网络基因Cbln 1的表达，以损害这些神经元内的社交能力。在 目的1：探讨催产素受体标记腹侧被盖区特异性群体的新概念 促进社交的催产素能神经元，这些神经元中的催产素受体活性是必要的 正常的社交。在目的2中，我们研究了VTA神经元促进VTA神经元的靶点。 通过测试化学发生学控制的活性和Grid 1表达（Cbln 1的突触后结合） 在自闭症中缺失的伴侣）是必要的，足以促进社会性。 腹侧被盖区神经元与延髓核神经元形成兴奋性突触， 这些突触因Cbln 1缺失和癫痫发作而受损。在目标3中，我们测试UBE 3A和 癫痫发作集中在表达催产素受体的特定腹侧被盖区神经元上， 如果这些缺陷可以通过将Cbln 1添加回这些缺陷来挽救， 专门的神经元。在目的4中，我们研究是否在体内化学发生增加催产素信号传导， 能挽救腹侧被盖区突触能神经元对丘脑底核的突触缺陷和社交能力的损害 由UBE 3A和癫痫发作引起。在这项研究中，我们将联合收割机条件小鼠遗传学， 包括VGluT 2和Oxtr启动子交叉的基于立体定位病毒载体的基因递送方法 遗传学、行为化学遗传学和脑切片光遗传学电生理学技术， 聚合分子自闭症基因网络和神经元回路，其中三种人类自闭症模型 谱系障碍损害社交能力。(1)Ube 3a基因剂量增加（母体15 q11 -13三倍）和（2） 癫痫会聚抑制腹侧被盖区神经元中的Cbln 1和（3）Grid 1、Cbln 1的丢失 突触后结合伴侣都损害社会性。我们还进行了一系列的体内 使用针对这些疾病的基于病毒载体的方法对治疗干预的功效进行临床前试验 分子、电路和催产素系统。