Characterization of SynGAP Mutations in Human Cognitive Disorders

项目摘要 最近对智力残疾(ID)、自闭症谱系障碍(ASD)和 精神分裂症(SCZ)提高了我们对人类认知的分子和细胞基础的理解 疾病。对这些基因的功能分类显示，影响基因的突变显著丰富 谷氨酸能突触的结构和功能。一种已被证明调节谷氨酸能的蛋白质 Synapses是SynGAP，是一种RasGAP，是脊柱形态发生和突触的关键负调控因子 Ras-ERK和依赖于蛋白质合成的信号通路的可塑性。德新星有害的SynGAP 据估计，突变约占ID病例的1%，并与ASD高度共存。 SynGAP变异也被发现是其他神经精神障碍的重要风险因素 包括SCZ和双相情感障碍(BP)。我们最近确定SynGAP是最强大的监管机构之一 使用200个SCZ相关风险基因的高通量筛选来确定突触大小和/或数量。此外, 我们发现ID/ASD相关的SynGAP突变也会影响突触的结构和功能。这些数据 支持人类SynGAP突变可能改变突触传递和可塑性的观点。至 确定疾病相关的SynGAP突变如何影响突触的病理生理和行为，我们将 首先用一种新的方法描述SynGAP疾病风险变异对突触结构和功能的影响 包括实时成像、生化和电生理技术在内的多种方法的结合。下一首, 我们将使用CRISPR/Cas9基因组编辑来生成携带SynGAP突变的小鼠模型 精确模拟SynGAP的人类疾病风险变体。对于这些老鼠，我们将确定它们是否有 不同的可塑性、环路和行为表型。最后，我们将执行基于机制的药物 筛选干扰SynGAP调节的信号转导通路以发现小分子(S) 可以改善突触和行为缺陷。这个拟议的项目将是第一个系统化的项目 疾病相关SynGAP突变对突触病理生理学和动物行为的影响。 这些研究将使我们能够深入了解SynGAP相关疾病的潜在机制，并为 新的治疗策略之路。

Project Summary Recent genome-wide association studies of Intellectual disability (ID), Autism spectrum disorder (ASD) and Schizophrenia (SCZ) have improved our understanding of the molecular and cellular basis of human cognitive diseases. Functional categorization of these genes has revealed a significant enrichment of mutations affecting glutamatergic synapse structure and function. One protein that has been shown to regulate glutamatergic synapses is SynGAP, a RasGAP that is a critical negative regulator of spine morphogenesis and synaptic plasticity via Ras-ERK and protein synthesis-dependent signaling pathways. De Novo deleterious SYNGAP mutations are estimated to account for approximately 1% of ID cases and are highly comorbid with ASD. SYNGAP variants have also been found to be a significant risk factor in other neuropsychiatric disorders including SCZ and bipolar disorder (BP). We recently identified SynGAP as one of the most potent regulators of synaptic size and/or number using a high-throughput screen of 200 SCZ-associated risk genes. In addition, we found that ID/ASD-associated SynGAP mutations also affect synaptic structure and function. These data support the notion that human SynGAP mutations might alter synaptic transmission and plasticity. To determine how disease-associated SynGAP mutations impact synaptic pathophysiology and behavior, we will first characterize the effect of SYNGAP disease risk variants on synapse structure and function using a combination of approaches including real time imaging, biochemical and electrophysiological techniques. Next, we will use CRISPR/Cas9 genome editing to generate mouse models carrying SynGAP mutations that precisely mimic human disease risk variants of SynGAP. With these mice we will determine whether they have differential plasticity, circuit and behavioral phenotypes. Finally, we will perform mechanism based drug screens to target disrupted SynGAP-regulated signal transduction pathways to discover small molecule(s) that can ameliorate synaptic and behavioral deficits. This proposed project would be the first systematic investigation of disease-associated SynGAP mutations on synaptic pathophysiology and animal behavior. These studies will allow us to gain insight into mechanisms underlying SynGAP-associated diseases and pave the way for novel therapeutic strategies.