The Role of GATOR1 in Cortical Malformations

项目总结 皮质发育畸形(MCD)是一组神经发育异常 以关节的一系列形态和结构异常为特征的疾病 反映胚胎大脑发育错误的大脑皮层。MCD关联 患有难治性癫痫，可能需要手术切除受影响的 脑组织。一些MCD是由神经胶质前体细胞发生的体细胞突变引起的 在已知的大脑受限区域导致皮质发育异常的细胞 为局灶性皮质发育不良(FCD)。特别是，影响基因的体细胞突变 哺乳动物雷帕霉素靶标(MTOR)信号通路与 FCD。最近，编码GATOR1的mTOR调控基因的突变 DEPDC5、NPRL2、NPLR3等复合体与FCD相关。而当 已知GATOR1调节mTOR信号以响应细胞氨基酸水平 在非神经系统中，到目前为止，还没有研究探讨神经营养因子的功能作用 这些基因存在于神经元或大脑发育过程中。因此，在目标1中，我们将定义 GATOR1亚基敲除(KD)对细胞大小和细胞迁移的影响及评估 这些影响是否依赖于mTOR。在目标2中，我们研究了功能角色 GATOR1在蛋白质合成、亚细胞定位和神经元兴奋性方面的作用。在……里面 目标3，我们评估GATOR1 KD如何改变大脑皮层的层叠并产生 新的FCD小鼠模型。我们将展示此模型中的FCD可以通过以下方法预防 MTOR抑制剂。这些研究将有助于理解GATOR1在体内的作用 皮质发育，并提供mTOR抑制剂的临床前评估 未来可能用于GATOR1相关性癫痫。

PROJECT SUMMARY Malformations of cortical development (MCD) are a group of neurodevelopmental disorders characterized by a range of morphological and structural abnormalities of the cerebral cortex reflecting errors in embryonic brain development. MCD are associated with medically refractory epilepsy and may require the surgical removal of the affected brain tissue. Some MCD result from somatic mutations occurring in neuroglial progenitor cells that result in abnormal cortical development in a restricted area of the brain known as focal cortical dysplasia (FCD). In particular, somatic mutations affecting genes in the mammalian target of rapamycin (mTOR) signaling pathway are highly associated with FCD. Recently, mutations in the mTOR regulatory genes encoding the GATOR1 complex e.g., DEPDC5, NPRL2, NPLR3, have been associated with FCD. While GATOR1 is known to modulate mTOR signaling in response to cellular amino acid levels in non-neuronal systems, to date, no studies have investigated the functional role for these genes in neurons or during brain development. Thus, in Aim 1, we will define the effects of GATOR1 subunit knockdown (KD) on cell size and cell migration and assess whether these effects are mTOR dependent. In Aim 2, we investigate the functional roles of GATOR1 in protein synthesis, subcellular localization, and neuronal excitability. In Aim 3, we assess how GATOR1 KD alters cerebral cortical lamination and generate a new mouse model of FCD. We will show that FCD in this model can be prevented with mTOR inhibitors. These studies will help to understand the role of GATOR1 during in cortical development and provide pre-clinical assessment of mTOR inhibitors for possible future use in GATOR1-associated epilepsies.