Roles for uniquely human enhancers in brain development and WNT signaling

人类独特的增强子在大脑发育和 WNT 信号传导中的作用

• 批准号: 10577092
• 负责人: Debra Silver
• 金额: $ 62.41万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-03-09 至 2027-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10577092
• 关键词: Acceleration; Address; Agonist; Apical; Behavior; Biological Assay; Biological Process; Brain; Cell Communication; Cell Cycle; Cells; Cerebral cortex; Code; Cognition; Complex; Data Set; Development; Embryo; Enhancers; Evolution; Exhibits; Gene Expression; Generations; Genes; Genetic; Genome; Genomic approach; Genomics; Goals; Human; Image; Immunofluorescence Immunologic; In Vitro; Individual; Intellectual functioning disability; Luciferases; Macaca; Modeling; Modification; Molecular; Mus; Mutation; Neocortex; Neuroanatomy; Neuroglia; Neurons; Nucleotides; Organoids; Pan Genus; Phenotype; Positioning Attribute; Primates; Proliferating; Regulation; Regulator Genes; Regulatory Element; Reporter; Research; Role; Schizophrenia; Signaling Molecule; Structure; Testing; Untranslated RNA; Variant; WNT Signaling Pathway; autism spectrum disorder; brain size; cell cortex; cell immortalization; cognitive capacity; epigenome editing; experimental study; fascinate; imaging approach; induced pluripotent stem cell; innovation; insight; mouse model; neocortical; nerve stem cell; nervous system disorder; neurogenesis; neuropsychiatric disorder; neuroregulation; nonhuman primate; progenitor; receptor; self-renewal; single-cell RNA sequencing; tool

ABSTRACT Humans diverge from other primates in numerous ways including their neuroanatomy and cognitive capacities. Human-specific features are particularly prominent in the cerebral cortex, which has undergone an expansion in size and acquired unique cellular composition and circuitry. Many of these features arose through modifications to cortical development, explained by human-specific gene expression. However, how human-specific gene expression explains divergent brain development is poorly understood. This proposal aims to fill that gap by investigating how non-coding regulatory loci impact human-specific brain development. Specifically, we focus on human accelerated regions (HARs), which are ultra-conserved sequences which have rapidly acquired mutations in the human lineage. HARs frequently physically associate with neurodevelopmental genes, and at least 50% of HARs have enhancer activity in human neural cells. Further, HARs are broadly associated with neurological disorders. Yet, biological functions for HARs in brain development remain largely unknown. Our group discovered HARE5, which shows divergent human-chimpanzee (Hs-Pt) enhancer activity in the developing mouse brain, due to just 4 mutations over 600 conserved nucleotides. HARE5 activates expression of Fzd8, a receptor in the WNT signaling pathway which is implicated in brain size and neurological disease. We have generated humanized HARE5 mouse models which exhibit expanded progenitor and neuron number and enlarged brains. We have additionally discovered new HARs, which like HARE5, are predicted to impact WNT signaling. This proposal will test the central hypothesis that evolutionary modifications of HAR enhancer activity modulate WNT signaling to control neural progenitor dynamics in the developing brain. Our proposal leverages our expertise and unique genetic tools, including mouse models, and human and non-human primate iPSCs and organoids. We will investigate mechanisms of HARE5 function in mouse models (Aim 1) and in cortical organoids generated from human and non-human primate iPSCs (Aim 2). We will then test roles for 12 WNT-associated HARs in neurogenesis (aim 3). Upon completion of this study, we will gain valuable insights into the developmental underpinnings of human cognitive capacities which can inform the basis for neuropsychiatric diseases.

抽象的 人类以多种方式与其他灵长类动物分歧，包括神经解剖学和认知能力。 人类特异性特征在大脑皮层中尤为突出，该皮质经历了扩展 尺寸并获得了独特的蜂窝组成和电路。这些功能中的许多通过修改产生 通过人类特异性基因表达来解释皮质发育。但是，人类特定基因如何 表达解释说，脑发育有分歧的理解很少。该建议旨在通过 研究非编码调节基因座如何影响人类特异性的大脑发育。具体来说，我们专注于 人类加速区域（HAR）是超级保存的序列，已迅速获得 人类谱系中的突变。经常与神经发育基因进行物理缔合，在 至少有50％的Hars在人类神经细胞中具有增强活性。此外，Hars与 神经系统疾病。然而，在大脑发育中har虫的生物学功能在很大程度上仍然未知。 我们的小组发现了Hare5，该Hare5显示了人类 - 奇曼齐（HS-PT）增强剂的不同 由于600多个保守核苷酸的突变仅4个突变，因此发展了小鼠脑。 Hare5激活表达 FZD8（Wnt信号通路中的一种受体，与脑大小和神经系统疾病有关。我们 已经产生了人性化的Hare5小鼠模型，该模型表现出扩展的祖细胞和神经元数，并且 大脑扩大。我们还发现了像Hare5一样的新野兔，预计会影响Wnt 信号。该提案将检验以下中心假设，即HAR增强剂的进化修改 活性调节WNT信号传导以控制发育中的大脑中的神经祖细胞动力学。我们的 提案利用我们的专业知识和独特的遗传工具，包括鼠标模型以及人类和非人类 灵长类动物IPSC和类器官。我们将研究鼠标模型中Hare5功能的机理（AIM 1）和 在人类和非人类灵长类动物IPSC产生的皮质器官中（AIM 2）。然后，我们将测试角色 神经发生中的12个与WNT相关的竖琴（AIM 3）。完成这项研究后，我们将获得宝贵的见解 进入人类认知能力的发展基础，这些基础可以为 神经精神疾病。