Dynamic control of cortical development and disease by mRNA stability

摘要 大脑皮层的发育需要精确的调控，以确保基因在大脑皮层中表达。 正确的细胞类型和适当的发育阶段。跨细胞类型的基因表达分析， 发展，揭示了细胞转录组的广泛多样性。然而，转录组数据集仅 提供基因表达的静态快照。转录本表达受转录速率之间的平衡的影响。 转录和RNA降解，但后者在皮质发育中的作用知之甚少。的 该提案的总体目标是揭示mRNA的稳定性如何有助于细胞的动态性质。 在皮质发育过程中的转录组。首先，我们将阐明，第一次，时间景观 皮质发育过程中mRNA的稳定性。我们将使用最先进的SLAM-seq方法来量化 在小鼠和人类模型中，mRNA在神经分化阶段的稳定性。这些数据将 询问以告知RNA降解的顺式和反式控制，并优先考虑受 稳定其次，我们将调查CCR 4-NOT复合物（中央调节器）组件的要求 RNA的稳定性，在皮质发育。我们的初步数据表明，hocT 3组分是必不可少的 大脑皮层的发育因此，我们将使用击倒方法和拯救实验来测量 hocT 3作为CCR 4-NOT复合物的一部分控制皮质发育的程度。如 这种复合物的组成部分在自闭症中发生突变，我们将研究这些突变如何损害皮质 发展完成后，我们的研究将建立第一个全面的mRNA库， 在小鼠和人类发育的稳定水平上动态调节。通过研究基因 RNA稳定因子对皮质生成的需求，我们将建立细胞命运如何的新范式。 在神经系统中调节并与疾病相关。这将共同开辟新的研究方向 大脑发育和疾病的分子控制基础。

Abstract Development of the cerebral cortex requires precise regulatory control to ensure genes are expressed in the correct cell types and at the proper developmental stages. Analyses of gene expression across cell types and development, have revealed extensive diversity in cellular transcriptomes. However, transcriptomic datasets only provide a static snapshot of gene expression. Transcript expression is influenced by a balance between rates of transcription and RNA degradation, yet the role of the latter in cortical development is poorly understood. The overall goal of this proposal is uncover how mRNA stability contributes to the dynamic nature of cellular transcriptomes across cortical development. First, we will elucidate, for the first time, the temporal landscape of mRNA stability during cortical development. We will use state-of-the-art SLAM-seq approaches to quantify mRNA stability across neural differentiation stages in both mouse and human models. These data will be interrogated to inform both cis and trans control of RNA degradation and to prioritize disease loci influenced by stability. Second, we will investigate requirements for components of the CCR4-NOT complex, a central regulator of RNA stability, in cortical development. Our preliminary data demonstrate the CNOT3 component is essential for cortical development. Thus, we will use knockdown approaches and rescue experiments to measure the extent to which CNOT3 controls cortical development as part of the CCR4-NOT complex. Further, as components of this complex are mutated in autism, we will investigate how these mutations impair cortical development. Upon completion, our studies will establish the first comprehensive repertoire of mRNAs that are dynamically regulated at the level of stability in mouse and human development. By investigating genetic requirements of RNA stability factors for corticogenesis, we will establish new paradigms for how cell fate is regulated in the nervous system and relevant for disease. Together, this will open up new research directions into the basis of molecular control of brain development and disease.