Understanding the neurodevelopmental role and mechanism of histone demethylase JMJD3

了解组蛋白去甲基化酶 JMJD3 的神经发育作用和机制

基本信息

批准号：
10618153
负责人：
DANIEL A LIM
金额：
$ 37.95万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-07-15 至 2025-04-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10618153
关键词：
Address Adult Architecture Area Behavior Behavioral Biological Models Brain CRISPR/Cas technology Childhood Brain Neoplasm Chromatin Cognitive deficits Complex Cytoplasmic Granules Data Development Disease Engineering Enhancers Epigenetic Process Gene Dosage Gene Expression Genes Genetic Genome Genomic Segment Genomics Goals Heterozygote Higher Order Chromatin Structure Hippocampus Histones Human Human Genome Impaired cognition Impairment Intellectual functioning disability Knowledge Learning Life Lysine Malignant Neoplasms Maps Memory Methods Methylation Molecular Mus Mutant Strains Mice Mutation Neurodevelopmental Disorder Neurons Nuclear Outcome Pharmacotherapy Phenotype Population Process Production Proteins Regulator Genes Research Role Structure Testing Tissues Transcriptional Activation autism spectrum disorder autosome cancer therapy chromatin modification dentate gyrus drug development emotional behavior experimental study gene repression histone demethylase human disease in vivo inhibitor innovation insight mouse development mouse model nerve stem cell nervous system disorder neurodevelopment neurogenesis novel postnatal promoter recruit single-cell RNA sequencing stem cell population

项目摘要

JMJD3 (KDM6B) is a chromatin regulator with roles central to normal development as well as a wide range of human diseases including cancer and human neurological disorders. For instance, mutations in JMJD3 are autosomal recessive for familial intellectual disability, and de novo JMJD3 mutations are associated with autism spectrum disorder (ASD). An important next step to understanding genetic causes of complex diseases is to study disease-associated genes in mouse models. While it is known that JMJD3 is important to certain aspects of neural cell development, whether JMJD3 deficiency can actually cause cognitive dysfunction has not been known. Preliminary Studies indicate that JMJD3 is critical for the development of the mouse hippocampal dentate gyrus (DG). In the DG, granule neurons are generated throughout life from a population of neural stem cells (NSCs). Defective DG neurogenesis impairs many hippocampal-dependent behaviors and has been associated with cognitive deficits including that of intellectual disability and ASD. Without Jmjd3, NSCs failed to become established in the adult DG, and granule neuron production was severely decreased and abnormal. In these mice, hippocampal-dependent learning was defective. Heterozygous deletion of Jmjd3 also resulted in abnormal postnatal DG development, indicating that this process is sensitive to gene dosage. Aim 1 is to determine the role of Jmjd3 in DG neurogenesis. In vivo experiments will test the hypothesis that Jmjd3 regulates the postnatal expansion and establishment of the DG NSC population, and that even reduced Jmjd3 gene dosage causes cognitive dysfunction. Single cell RNA sequencing analysis will provide molecular insights into the observed phenotype and help guide mechanistic studies of Aim 2. Aim 2 is to determine the mechanisms by which JMJD3 regulates gene expression. JMJD3 has demethylase activity for histone 3 lysine 27 trimethylation (H3K27me3), which is a chromatin modification associated with transcriptional repression. To investigate demethylase-dependent and potential demethylase-independent activities of JMJD3, we have developed innovative CRISPR-based technologies to recruit JMJD3 proteins to the genome. By developing a novel, easy-to-use method for mapping lamina-associated domains (LADs) – a repressive nuclear compartment – we have also found that JMJD3 in NSCs is enriched at the genomic LAD “borders,” which are genomic regions enriched for transcriptional regulatory elements. Thus, we propose investigating the role of JMJD3 in regulating this aspect of higher-order chromatin structure. The proposed neurodevelopmental and behavioral analyses combined with mechanistic studies is expected to provide a scientific framework in which to begin understanding how human JMJD3 mutations can cause disease. The studies of JMJD3 mechanism is also expected to be important to the broader field of chromatin-based epigenetics as well as nuclear compartment-associated genome organization – an emerging area of research.

JMJD3（KDM6B）是一种染色质调节剂，具有正常发育和广泛范围的角色包括癌症和人类神经系统疾病在内的人类疾病。例如，JMJD3中的突变为针对家庭肠道残疾的常染色体隐性和从头JMJD3突变与自闭症谱系障碍（ASD）。了解复杂疾病的遗传原因的重要下一步是在小鼠模型中研究与疾病相关的基因。虽然众所周知JMJD3对确定很重要神经细胞发育的各个方面，JMJD3缺乏是否实际上会导致认知功能障碍未知。初步研究表明JMJD3对于小鼠的发展至关重要海马齿状回（DG）。在DG中，颗粒神经元在人群中产生神经元干细胞（NSC）。 DG神经发生有缺陷会损害许多海马依赖性行为和与包括智力残疾和ASD在内的认知缺陷有关。没有JMJD3， NSC无法在成人DG中建立，并且颗粒神经元的产生严重先进和异常。在这些小鼠中，海马依赖性学习有缺陷。杂合删除 JMJD3还导致异常产后DG发育，表明此过程对基因敏感剂量。目的1是确定JMJD3在DG神经发生中的作用。体内实验将测试 JMJD3的假设调节了DG NSC人群的产后扩张和建立，以及即使降低JMJD3基因剂量也会引起认知功能障碍。单细胞RNA测序分析将对观察到的表型提供分子见解，并有助于指导目标2。确定JMJD3调节基因表达的机制。 JMJD3具有用于脱甲基酶的活性组蛋白3赖氨酸27三甲基化（H3K27me3），它是与染色质修饰相关的转录表示。研究脱甲基酶依赖性和潜在脱甲基酶独立的 JMJD3的活动，我们开发了创新的基于CRISPR的技术来招募JMJD3蛋白基因组。通过开发一种新颖的，易于使用的方法来映射层层相关域（LADS） - 抑制性核室 - 我们还发现，NSC中的JMJD3在基因组LAD上富含 “边界”，是富含转录调节元件的基因组区域。那我们建议研究JMJD3在调查高阶染色质结构方面的作用。提议神经发育和行为分析与机械研究相结合，有望提供科学框架开始了解人类JMJD3突变如何引起疾病。这预计JMJD3机制的研究对基于染色质的更广泛领域很重要表观遗传学以及与核区室相关的基因组组织 - 新兴领域。