Understanding the interaction between sleep and SHANK3/B-catenin signaling in Autism

项目摘要 睡眠问题在自闭症谱系障碍（ASD）中的发生率高于典型的 发展入睡问题可预测ASD核心症状的严重程度及相关因素 问题行为，并导致慢性睡眠剥夺（SD）。了解睡眠的影响 剥夺之所以重要，是因为它对认知、注意力和情绪调节产生不利影响。 尽管如此，人们对导致睡眠异常的机制或 ASD中慢性睡眠缺失的后果。确定这些机制可能会带来新的 改善患者及其家属的生活质量。遗传学的研究 ASD诊断率高的证型为ASD的发病机制提供了重要线索。一个这样 在另一个实施例中，该综合征是以SHANK 3基因缺失为特征的麦克德米德综合征（PMS）。 SHANK 3突变也经常在特发性ASD患者中发现。We previously showed ASD睡眠表型在Shank 3 C末端缺失的小鼠中重现， （Shank 3 C），尽管昏昏欲睡（即SD后），但仍难以入睡。我们还表明，SD 与WT相比，在Shank 3 β C动物中诱导更多数量的基因表达差异。因此，我们认为， 我们假设Shank 3 β C动物对SD表现出异常的转录应答。的 本建议的目的是确定异常反应的机制 以Shank 3突变小鼠为模型，我们的初步研究表明，SD 增加全长SHANK 3a的核定位，这是一种在Shank 3 β C中不存在的同种型 被认为是主要的突触。SHANK 3结合β-连环蛋白。β-连环蛋白易位 进入细胞核通过染色质重塑调节转录， 发展过程。我们的初步研究表明，SD产生的变化，染色质 拓扑结构，其中一些变化并不发生在Shank 3神经元中， 动物因此，我们的中心假设是，SD改变了染色质拓扑结构和基因， 通过增加细胞核SHANK 3a和b-连环蛋白表达， Shank 3 C3 C干扰了这一过程。为了验证我们的假设，在目标1中，我们将首先确定 SD在SHANK 3a/b-catenin突触核信号传导中的作用。然后，在目标2中，我们将确定 SD对SHANK 3依赖性染色质拓扑结构和单核分辨率转录的影响。 我们将研究两个对ASD很重要并受到睡眠不足影响的大脑区域：前额叶皮层 和海马随后，我们将测试通过组学研究优先考虑的候选人， 影响睡眠的能力。这些目标的完成将使我们能够确定睡眠如何与 SHANK 3和β-catenin调节染色质和基因表达。

PROJECT SUMMARY Sleep problems occur at a higher rate in Autism Spectrum Disorder (ASD) than in typical development. Problems falling asleep predict severity of ASD core symptoms and associated problem behaviors, and lead to chronic sleep deprivation (SD). Understanding the effects of sleep deprivation is important because it adversely affects cognition, attention and emotional regulation. Nonetheless, little is known about the mechanisms responsible for abnormal sleep or the consequences of chronic sleep loss in ASD. Identifying these mechanisms may lead to new interventions that will improve quality of life of patients and their families. The study of genetic syndromes with high rate of ASD diagnosis has provided important clues into mechanisms. One such syndrome is Phelan McDermid Syndrome (PMS), characterized by deletions in the SHANK3 gene. Mutations in SHANK3 are also often found in patients with idiopathic ASD. We previously showed that the ASD sleep phenotype is recapitulated in mice with a C-terminal deletion in Shank3 (Shank3∆C), which struggle to fall asleep despite being sleepy (i.e. after SD). We also showed that SD induces greater number of differences in gene expression in Shank3∆C animals than WT. Therefore, we hypothesize that Shank3∆C animals display an abnormal transcriptional response to SD. The objective of this proposal is to identify the mechanisms that underlie the abnormal response to SD in ASD, using Shank3 mutant mice as a model. Our preliminary studies show that SD increases the nuclear localization of full-length SHANK3a, an isoform that is absent in Shank3∆C animals and thought to be primarily synaptic. SHANK3 binds b-catenin. Translocation of β-catenin into the nucleus regulates transcription through chromatin remodeling and is key to many developmental processes. Our preliminary studies show that SD produces changes in chromatin topology in glutamatergic neurons, and that some of these changes do not take place in Shank3∆C animals. Therefore, our central hypothesis is that SD changes chromatin topology and gene expression by increasing nuclear SHANK3a and b-catenin and that the absence of SHANK3a in Shank3∆C interferes with this process. To test our hypothesis, in Aim 1, we will first determine the effects of SD in SHANK3a/b-catenin synaptic-nuclear signaling. Then, in Aim 2, we will determine the effect of SD in SHANK3-dependent chromatin topology and transcription at single-nuclear resolution. We will examine two brain regions important to ASD and impacted by sleep loss: pre-frontal cortex and hippocampus. We will subsequently test candidates prioritized through omic studies for their ability to influence sleep. Completion of these aims will allow us to determine how sleep interacts with SHANK3 and β-catenin to regulate chromatin and gene expression.