Functional Interrogation of Chromatin Remodeling Gene in Brain Development

神经细胞的发育和哺乳动物大脑的形成是由基因表达精确组织的。基因转录受群转录因子（TFs）和许多表观遗传因子（包括染色质重塑蛋白）的调控。虽然关于tf如何调节哺乳动物大脑特定细胞类型的各种发育过程和功能结果的知识丰富，但对染色质重塑蛋白在这些过程中的贡献知之甚少。

Background | Development of nerve cells and the formation of the mammalian brain is precisely organized by gene expression. Gene transcription is regulated by groups transcriptional factors (TFs) and many epigenetic factors, including chromatin remodeling proteins. While a wealth of knowledge exists about how TFs regulate various developmental processes and functional outcomes of specific cell types the mammalian brain, little is known about the contribution of chromatin remodeling proteins in such processes. Objectives and Approaches | Our aims in this NSERC DG are to examine how one of these proteins, Chd8, controls the transcriptome of neuronal subtypes and what impact this has on the morphological development of these sub-types, and how this, in turn, affects physiological function. We will cross mouse harboring Chd8fl/fl together with Rosa 26-td-tomato and cell-type-specific Cre lines in this project. We will start with neuronal, and glial subtype-specific Cre lines, including NEX-Cre, VIAAT-Cre, and GFAP-Cre. Our specific aims are: - Aim 1: To identify and compare the genome-wide, transcriptional signature, after removing of Chd8 in specific types of brain cells. The deletion of Chd8 and simultaneously labeling with td-tomato allows us to analyze a homogeneous population of cells from brain tissues, and to carry out genome-wide transcriptional analysis using RNA-Seq. - Aim 2: To determine the morphological alterations caused by completely Chd8 deletion in specific types of neurons. We will carry out assays to examine the survival, migration, dendritic outgrowth and synaptic density resulting from removal of Cdh8. - Aim 3: To determine the functional outcomes caused by completely knocking out of Chd8 in subtypes of cells. We will characterize both excitatory and inhibitory neurons on their firing of action potential, excitatory and inhibitory inputs using slice electrophysiology. Outcomes and Significance | This NSERC DG will lead to the training of Highly Qualified Personnel, including one postdoc fellow and two Ph.D. students who will leave my lab armed with substantial expertise in neuroscience research. These experiments will provide a direct, in vivo evidence regarding how a chromatin regulator (Chd8 gene) contribute to subtype-specific transcriptome, and endow neurons and glial cells with diverse, complex properties, which will enable a comprehensive picture for the genetic regulation of brain development in mammals. The results, insights, and methods that will come out of our studies will provide a tractable strategy for addressing the rules by which specific chromatin-remodeling proteins can lead to unique neuronal and glial subtype specification in the future, which is a fundamental question in neuroscience, and a long-term goal of my lab.