Epigenetic Maintenance of Neural Cell Identity

神经细胞身份的表观遗传维持

• 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
• 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

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神经发育障碍。 通常以精神损害为特征的病理。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显著相关。这类 转录调节因子被认为通过加强遗传沉默来稳定神经细胞的特性和功能 谱系非特异性基因通过表观遗传染色质修饰。然而，由于大多数异染色质 修饰物是普遍表达的，缺乏序列特异性，（1）如何精确靶向抑制性 （2）一般异染色质修饰剂中的突变如何有助于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ZNF 462招募异染色质的机制 改性剂EHMT 1/2。我们将测试ZNF 462是否以及如何限制谱系非特异性基因表达 并维持神经细胞的特性ZNF 462单倍不足导致Weiss-Kruszka综合征，一种复杂的 以神经发育缺陷为特征的NDD，包括发育迟缓和自闭症。但 C2 H2锌指蛋白的神经发育作用尚不清楚。我们之前发现老鼠 Zfp 462是内胚层基因阻遏所必需的，指导Ehmt 1/2依赖的异染色质， 转座因子（TE）衍生的增强子在神经祖细胞中的作用。我们假设人类ZNF 462 控制兼性异染色质的形成，通过特异性限制非神经基因的表达， 神经发生然而，我们预测，由于TE的快速物种特异性进化，ZNF 462将具有 新的人类靶点并控制独特的基因调控网络。因此，我们将：（目标1）采用神经 人胚胎干细胞（hESC）的分化偶联表观基因组和转录组分析， 研究ZNF 462杂合性对维持神经基因表达的影响，目的2 ZNF 462蛋白结构域在mESCs中结构-功能分析和功能互补 负责同源二聚化、DNA结合和转录抑制，以及（目的3）CTCF谱 结合和三维染色体构象的神经上皮干细胞（NESC），以调查 ZNF 462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， ZNF 462依赖性基因沉默的分子机制的新见解，并提高我们的研究水平。 了解Weiss-Kruszka综合征的病因。以下策略将揭示 基因调控和神经生物学，并阐明异染色质修饰剂突变之间的联系， 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提供新的策略。 失调