The role of the mRNA decay factor CNOT3 in cortical development

摘要 大脑皮层发育过程中基因表达的适当空间和时间控制， 对于神经祖细胞的维持和神经分化至关重要。而转录调控 长期以来被认为是皮质发育过程中基因表达控制的关键， RNA衰变的贡献还不太清楚。尽管如此，基因表达的错误调节， 转录后水平正在成为神经发育疾病的主要原因，包括智力障碍。 残疾和自闭症。hocT 3是一种mRNA稳定性的调节因子，最近发现在一个队列中发生了突变， 患有智力残疾和自闭症的病人。其他研究表明，hocT 3调节 转录本编码的蛋白质参与细胞周期调控和干细胞命运的稳定性。尽管有联系 Cnot 3，mRNA降解，神经发育疾病，Cnot 3如何促进大脑发育， 以及它在这个过程中的主要目标，都是未知的。我将使用Cre-lox条件来解决这个知识差距 敲除小鼠模型以消除神经祖细胞中的Cnot 3表达。初步数据显示， 胚胎（E）14.5天（大约神经发生中期），cKO小鼠表现出小头畸形、细胞凋亡，以及 减少活跃增殖细胞的数量。在本提案中，我将以这些意见为基础， 测试hocT 3介导的mRNA稳定性调节是适当的皮质 发展目的1研究Cnot 3破坏对皮质生成的影响，并使用实时成像 方法来监测祖先命运决定中对hocT 3的要求。Aim 2使用最先进的 技术，以全球监测mRNA的稳定性在神经祖细胞和评估的后果Cnot 3 缺失对mRNA稳定性的影响这些方法将揭示hocT 3在皮质神经元中先前未表征的作用。 发展，同时提供了一个前所未有的看法，RNA稳定性在皮质发育，以及如何其 调节不当会导致疾病。

ABSTRACT Proper spatial and temporal control of gene expression during development of the cerebral cortex is critical for the maintenance of neural progenitors and for neural differentiation. While transcriptional regulation has long been recognized as critical to the control of gene expression during cortical development, the contribution of RNA decay is less well understood. Despite this, mis-regulation regulation of gene expression at the post-transcriptional level is emerging as a major cause of neurodevelopmental diseases, including intellectual disability and autism. CNOT3, a regulator of mRNA stability, has recently been found to be mutated in a cohort of patients suffering from intellectual disability and autism. Additional studies have shown that CNOT3 regulates the stability of transcripts encoding proteins involved in cell cycle regulation and stem cell fate. Despite the links between Cnot3, mRNA degradation, neurodevelopmental disease, how Cnot3 contributes to brain development, and its key targets in this process, are unknown. I will address this knowledge gap using a Cre-lox conditional knockout mouse model to ablate Cnot3 expression in neural progenitors. Preliminary data indicates that at embryonic day (E)14.5 (approximately mid-neurogenesis), cKO mice exhibit microcephaly, apoptosis, and a reduction in the number of actively proliferating cells. In this proposal, I will build upon these observations and test the overall hypothesis that that CNOT3-mediated regulation of mRNA stability is required for proper cortical development. Aim 1 investigates the impact of Cnot3 disruption across corticogenesis, and uses live imaging approaches to monitor the requirements for CNOT3 in progenitor fate decisions. Aim 2 uses state-of-the-art technology to globally monitor mRNA stability in neural progenitors and assess the consequences of Cnot3 deletion on mRNA stability. These approaches will reveal previously uncharacterized role for CNOT3 in cortical development, while providing an unprecedented view of RNA stability during cortical development, and how its mis-regulation contributes to disease.