Epigenetic Maintenance of Neural Cell Identity

神经细胞身份的表观遗传维持

基本信息

批准号：
10295715
负责人：
Oliver Bell
金额：
$ 41.25万
依托单位：
UNIVERSITY OF SOUTHERN CALIFORNIA
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-08-10 至 2026-05-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10295715
关键词：
3-Dimensional Affect Architecture Automobile Driving Binding Binding Sites Biochemical Biological Biological Assay C2H2 Zinc Finger CCCTC-binding factor CRISPR screen Cell Differentiation process Cells Child Chromatin Chromosomes Complement Complex Coupled DNA Binding DNA Binding Domain DNA Transposable Elements Defect Development Developmental Delay Disorders Developmental Gene Disease Endoderm Endoderm Cell Enhancers Ensure Epigenetic Process Epithelial Essential Genes Etiology Evolution Failure GATA4 gene Gene Expression Gene Expression Profile Gene Expression Regulation Gene Silencing Genes Genetic Genetic Diseases Genetic Enhancer Element Genetic Predisposition to Disease Genetic Transcription Genome Genomics Goals Heritability Heterochromatin Heterozygote Homodimerization Human Impairment Knockout Mice Link Maintenance Mediating Methods Missense Mutation Molecular Molecular Conformation Monitor Mus Mutation Neuraxis Neurobiology Neurodevelopmental Disorder Neuroepithelial Neurons Orthologous Gene Pathology Phenotype Play Protein Isoforms Proteins Regulation Regulator Genes Reporter Reporter Genes Research Role SOX17 gene Specificity Structure Syndrome Tertiary Protein Structure Testing Traction Variant Work autism spectrum disorder chromatin modification de novo mutation embryonic stem cell epigenetic silencing epigenome euchromatic histone methyltransferase 1 exome sequencing experimental study gene repression genetic corepressor genome sequencing heterochromatin-specific nonhistone chromosomal protein HP-1 histone modification human embryonic stem cell insight loss of function mutation nerve stem cell neurodevelopment neurogenesis neuropathology neuropsychiatry novel novel strategies novel therapeutics prevent public health relevance recruit relating to nervous system risk variant stem cell differentiation stem cells transcription factor transcriptome whole genome

项目摘要

Neurodevelopmental disorders (NDDs) comprise a group of genetically and phenotypically heterogeneous pathologies commonly characterized by psychiatric impairment. The molecular basis of these neuropathologies remains poorly understood. Recent whole-genome-sequencing studies revealed that mutations in genes encoding heterochromatin modifiers are significantly associated with NDDs. This class of transcriptional regulators is thought to stabilize neural cell identity and function by enforcing heritable silencing of lineage non-specific genes through epigenetic chromatin modifications. However, since most heterochromatin modifiers are ubiquitously expressed and lack sequence-specificity, (1) how precise targeting of repressive chromatin is controlled and (2) how mutations in general heterochromatin modifiers contribute to NDD- associated neuronal defects remains unclear. To gain experimental traction on these questions, we will examine the mechanism by which a high-confidence NDD risk gene, ZNF462, recruits the heterochromatin modifiers EHMT1/2. We will test whether and how ZNF462 restricts lineage non-specific gene expression and maintains neural cell identity. ZNF462 haploinsufficiency causes Weiss-Kruszka syndrome, a complex NDD characterized by neurodevelopmental defects including developmental delay and autism. However, the neurodevelopmental role of the C2H2 zinc finger protein is unknown. We previously discovered that mouse Zfp462, is required for endodermal gene repression, directing Ehmt1/2-dependent heterochromatin to transposable element (TE)-derived enhancers in neural progenitor cells. We hypothesize that human ZNF462 controls facultative heterochromatin formation, by specifically restricting non-neural gene expression during neurogenesis. However, we predict that due to rapid species-specific evolution of TEs, ZNF462 will have novel human targets and control a distinct gene regulatory network. W e will therefore: (Aim 1) employ neural differentiation of human embryonic stem cells (hESCs) coupled to epigenome and transcriptome profiling to investigate the impact of ZNF462 heterozygosity on maintenance of neural gene expression, (Aim 2) perform structure-function analysis and functional complementation in mESCs to identify ZNF462 protein domains responsible for homodimerization, DNA binding and transcriptional repression and (Aim 3) profile CTCF binding and three-dimensional chromosome conformation in neuroepithelial stem cells (NESCs) to investigate the impact of ZNF462 heterozygosity on neuro-specific genome architecture. Our proposal provides a path to novel insight into the molecular mechanism of ZNF462-dependent gene silencing, and enhance our understanding of the etiology of Weiss-Kruszka syndrome. The following strategy will reveal new concepts in gene regulation and neurobiology and elucidate the link between mutations in heterochromatin modifiers and NDDs. Overall, our work will inform novel strategies to prevent and treat NDDs arising from epigenetic dysregulation.

神经发育障碍 (NDD) 包括一组遗传和表型异质性的疾病通常以精神障碍为特征的病理学。这些的分子基础神经病理学仍然知之甚少。最近的全基因组测序研究表明编码异染色质修饰物的基因突变与 NDD 显着相关。这一类的转录调节因子被认为通过执行可遗传的沉默来稳定神经细胞的身份和功能通过表观遗传染色质修饰来修饰谱系非特异性基因。然而，由于大多数异染色质修饰因子普遍表达且缺乏序列特异性，（1）抑制性靶向的精确度如何染色质受到控制，以及 (2) 一般异染色质修饰物中的突变如何导致 NDD- 相关的神经元缺陷仍不清楚。为了获得这些问题的实验牵引力，我们将研究高可信度 NDD 风险基因 ZNF462 招募异染色质的机制修饰符 EHMT1/2。我们将测试 ZNF462 是否以及如何限制谱系非特异性基因表达并维持神经细胞的身份。 ZNF462 单倍体不足导致 Weiss-Kruszka 综合征，这是一种复杂的疾病 NDD 的特征是神经发育缺陷，包括发育迟缓和自闭症。然而， C2H2 锌指蛋白的神经发育作用尚不清楚。我们之前发现鼠标 Zfp462 是内胚层基因抑制所必需的，指导 Ehmt1/2 依赖性异染色质神经祖细胞中转座元件（TE）衍生的增强子。我们假设人类 ZNF462 通过特异性限制非神经基因的表达来控制兼性异染色质的形成神经发生。然而，我们预测，由于 TE 的快速物种特异性进化，ZNF462 将具有新的人类目标并控制独特的基因调控网络。因此，我们将：（目标 1）采用神经网络人胚胎干细胞 (hESC) 的分化与表观基因组和转录组分析相结合研究 ZNF462 杂合性对维持神经基因表达的影响，（目标 2）执行 mESC 中的结构功能分析和功能互补，以鉴定 ZNF462 蛋白结构域负责同二聚化、DNA 结合和转录抑制以及（目标 3）CTCF 概况神经上皮干细胞 (NESC) 中的结合和三维染色体构象进行研究 ZNF462 杂合性对神经特异性基因组结构的影响。我们的建议提供了一条途径对 ZNF462 依赖性基因沉默分子机制的新见解，并增强我们的研究能力了解 Weiss-Kruszka 综合征的病因。以下策略将揭示新概念基因调控和神经生物学，并阐明异染色质修饰物和突变之间的联系 NDD。总的来说，我们的工作将为预防和治疗表观遗传引起的 NDD 提供新策略失调。