Rescuing SYNGAP1 haploinsufficiency by redirecting alternative splicing

项目摘要 突触传递和可塑性是神经元功能的基础，并且突触传递和可塑性的失调是神经元功能的基础。 蛋白质表达是神经发育障碍如自闭症的直接原因。超过100德 SYNGAP 1中的新生功能丧失突变与自闭症谱系障碍明确相关， 精神障碍和智力残疾。最近在剪接转换寡核苷酸（SSO）方面的成功表明， 通过遗传和SSO介导的切除来重定向剪接是一种有希望的拯救方法， 单倍不足我们已经在SYNGAP 1中发现了一个导致无意义的选择性剪接事件- 介导的mRNA衰变（NMD）。要确定SYNGAP 1是否 NMD外显子是一个可行的治疗靶点，我们利用遗传学方法研究其调控机制和功能， 方法，并确定SYNGAP 1 NMD外显子的遗传缺失和SSO抑制是否可以 在小鼠突变体和患者iPSC衍生的神经元中拯救杂合敲除表型。后 完成后，该项目将为SYNGAP 1 NMD外显子的生理功能提供遗传学见解 并产生关键的临床前试剂以从单倍不足恢复SYNGAP 1蛋白表达。

PROJECT SUMMARY Synaptic transmission and plasticity are fundamental to neuronal functions, and dysregulations of synaptic protein expression are direct causes of neurodevelopmental disorders such as autism. Over one hundred de novo loss-of-function mutations in SYNGAP1 have been unambiguously associated with autism spectral disorders and intellectual disability. Recent success in splice-switching oligonucleotides (SSOs) suggests that redirecting splicing through genetic and SSO-mediated ablations is a promising approach to rescue haploinsufficiency. We have identified an alternative splicing event in SYNGAP1 that leads to nonsense- mediated mRNA decay (NMD) during mouse and human development. To determine whether the SYNGAP1 NMD exon is a viable therapeutic target, we investigate the regulatory mechanism and its functions using genetic approaches, and determine whether genetic deletion and SSO suppression of the SYNGAP1 NMD exon can rescue heterozygous knockout phenotypes in mouse mutants and patient-iPSC-derived neurons. Upon completion, this project will provide genetic insights into the physiological functions of this SYNGAP1 NMD exon and generate critical preclinical reagents to restore SYNGAP1 protein expression from haploinsufficiency.