Epigenetics-Based Autism Treatment with Animal Models and Human Stem Cells

总结 该项目旨在发现新的药物干预自闭症的核心症状，包括社会 缺陷和重复行为。自闭症的致病因素之一是Shank 3基因的缺失， 在突触处编码支架蛋白。我们将使用Shank 3缺陷小鼠模型， 人类干细胞衍生的神经元在这个药物发现的奋进。遗传学研究发现， 自闭症中被破坏的基因是介导组蛋白甲基化/去甲基化的组蛋白修饰酶， 在转录调控中起关键作用。我们的初步研究发现组蛋白赖氨酸4 二甲基化（H3 K4 me 2，与基因激活有关）在前额叶皮层（PFC）中显著减少， 自闭症人类和Shank 3缺陷小鼠。H3 K4 me 2被赖氨酸特异性组蛋白去甲基化酶去甲基化 1（LSD 1，KDM 1A），发现其在Shank 3缺陷小鼠的PFC神经元中增加。我们假设 抑制LSD 1升高H3 K4 me 2并恢复基因表达可能能够改善自闭症样 表型，因此为自闭症提供了一种新的治疗策略。结合行为学，生物化学， 将使用电生理学、基因组学和干细胞方法来检验这一假设。目标1，我们将 表征自闭症小鼠模型中的表观遗传变化和表观遗传剂的治疗效果。的 组蛋白甲基化标记和组蛋白去甲基化酶的改变也将在Shank 3- 缺陷小鼠和自闭症人类死后组织。目的二，揭示其分子机制 自闭症模型的表观遗传治疗。突触反应和神经元兴奋性将是 在用LSD 1抑制剂处理的Shank 3缺陷小鼠中记录。基因表达的全基因组改变 和组蛋白甲基化将使用RNAseq和ChIPseq检查。确定关键字的因果作用 还将确定LSD 1抑制剂的治疗效果中的分子。在目标3中，我们将研究 Shank 3型ASD患者神经元的分子改变及治疗策略 单倍不足为了找出在Shank 3小鼠模型中发现的表观遗传治疗策略是否可能 我们也在自闭症患者中工作，我们将使用创新的干细胞技术来检查LSD 1的能力 逆转ASD患者神经元中的突触缺陷和分子畸变的抑制剂， 多能干细胞这项研究的结果不仅揭示了重要的自闭症之间的机械联系， 风险因素，但也揭示了自闭症的机制为基础的治疗策略。

Summary This project aims to discover novel pharmacological intervention for core symptoms of autism, including social deficits and repetitive behaviors. One of the causal factors of autism is the loss of Shank3 gene, which encodes a scaffolding protein at glutamatergic synapses. We will use Shank3-deficient mouse models and human stem cell-derived neurons in this drug discovery endeavor. Genetics studies have found that many of genes disrupted in autism are histone-modifying enzymes that mediate histone methylation/demethylation, which play a key role in transcriptional regulation. Our preliminary studies have found that histone lysine 4 dimethylation (H3K4me2, linked to gene activation) is significantly decreased in the prefrontal cortex (PFC) of autistic humans and Shank3-deficient mice. H3K4me2 is demethylated by lysine-specific histone demethylase 1 (LSD1, KDM1A), which is found to be increased in PFC neurons of Shank3-deficient mice. We hypothesize that inhibiting LSD1 to elevate H3K4me2 and restore gene expression may be able to ameliorate autism-like phenotypes, therefore providing a novel therapeutic strategy for autism. Combined behavioral, biochemical, electrophysiological, genomic and stem cell approaches will be used to test this hypothesis. Aim 1, we will characterize epigenetic changes and therapeutic effects of epigenetic agents in mouse models of autism. The alteration of histone methylation marks and histone demethylases will also be examined in PFC of Shank3- deficient mice and autism human postmortem tissues. Aim 2, we will reveal the molecular mechanisms underlying epigenetic treatment of autism models. Synaptic responses and neuronal excitability will be recorded in Shank3-deficient mice treated with LSD1 inhibitors. Genome-wide alteration of gene expression and histone methylation will be examined using RNAseq and ChIPseq. The causal role of identified key molecules in the therapeutic effects of LSD1 inhibitors will also be determined. In Aim 3, we will examine the molecular alteration and treatment strategy in human neurons from ASD patient with Shank3 haploinsufficiency. To find out whether the epigenetic treatment strategy found in Shank3 mouse models might also work in autism patients, we will use the innovative stem-cell technology to examine the capability of LSD1 inhibitors to reverse synaptic deficits and molecular aberrations in ASD patient’s neurons derived from induced pluripotent stem cells. Results from this study will not only reveal the mechanistic link among important autism risk factors, but also uncover a mechanism-based treatment strategy for autism.