Functional Genomics of Bipolar Disorder

双相情感障碍的功能基因组学

• 批准号: 10011360
• 负责人: Francis J McMahon
• 金额: $ 197.83万
• 依托单位: NATIONAL INSTITUTE OF MENTAL HEALTH
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10011360
• 关键词: 16p11.2; Affect; Alleles; Alternative Splicing; Amish; Anterior; Anxiety Disorders; Autopsy; Behavioral; Binding; Biochemical; Biological; Biological Assay; Biological Models; Biology; Bipolar Disorder; Blood; Brain; Brain imaging; CRISPR/Cas technology; Catalogs; Cause of Death; Cell Line; Cell model; Cells; Cessation of life; Characteristics; Chromosomes; Chronic; Circadian Rhythms; Collaborations; Copy Number Polymorphism; DNA; DNA Sequence; DNA Sequence Alteration; Data; Diagnosis; Diffusion Magnetic Resonance Imaging; Disease; Electrophysiology (science); Enrollment; Event; Family; Fibroblasts; Future; Gene Expression; Gene Expression Profile; Gene Mutation; Genes; Genetic; Genetic Variation; Genetic study; Genotype; Goals; Growth; Human; Human Volunteers; Image; Impairment; Individual; Lead; Length; Life; Light; Major Depressive Disorder; Measures; Mendelian disorder; Mennonite; Mental Depression; Mental disorders; Meta-Analysis; Methods; Mitogen-Activated Protein Kinases; Modeling; Molecular; Mood Disorders; Moods; Morphology; Mutation; National Heart, Lung, and Blood Institute; National Human Genome Research Institute; National Institute of Neurological Disorders and Stroke; Neurobiology; Neurodevelopmental Disorder; Neuroglia; Neurons; Nuclear Pore Complex; Occupational; Participant; Pathway interactions; Patients; Pharmaceutical Preparations; Pharmacology; Phenotype; Process; Public Health; Publishing; Regenerative Medicine; Resolution; Resources; Risk; Risk Factors; Role; SNP array; Sample Size; Sampling; Schizophrenia; Scientist; Signal Transduction; Skin; Smith Magenis syndrome; Source; Stem cells; Structure; Suicide; Symptoms; Technology; Testing; Therapeutic; Therapeutic Agents; Tissues; Transcript; Translating; United States National Institutes of Health; Validation; Valproic Acid; Variant; Work; age group; base; brain cell; brain tissue; causal variant; cell motility; cell type; cingulate cortex; connectome; differential expression; disability; dosage; endophenotype; experimental study; functional genomics; genetic variant; genome editing; genome wide association study; healthy volunteer; high risk; high throughput screening; imaging genetics; induced pluripotent stem cell; insight; interest; kinase inhibitor; microscopic imaging; neurodevelopment; neuroimaging; neuronal growth; neuropsychiatric disorder; novel; novel therapeutics; overexpression; risk variant; screening; severe mental illness; single cell sequencing; single-cell RNA sequencing; social; stem cell differentiation; stem cell technology; stressor; tool; transcription factor; transcriptome; transcriptome sequencing; transcriptomics

NCT00001174 In order to better interpret the impact of genetic variation on the brain biology of bipolar disorder (BD), we are pursuing a variety of functional genomics studies, including brain imaging, RNA-sequencing in post-mortem brain tissue, and cellular phenotyping of neurons derived from induced pluripotent stem cells. We have contributed genotypes and imaging data to the Enhancing NeuroImaging Genetics through Meta-Analysis (ENIGMA) brain imaging consortium, which brings together imaging and genetics data from around the world to generate large sample sizes needed for robust results. In addition, enrollees in our ongoing Amish Mennonite Bipolar Genetics study (AMBiGen, ZIA-MH002843) are referred for diffusion tensor imaging thru the Amish Connectome Study. Neuroimaging endophenotypes may shed light on the mechanisms whereby common genetic variants influence risk for psychiatric disorders. We have completed RNA-sequencing in 200 postmortem brain samples obtained from people with and without major psychiatric disorders (BD, schizophrenia and major depression). This study focused on the subgenual anterior cingulate cortex, especially implicated in people with mood disorders. The results illustrate the enormous diversity of brain-expressed transcripts, demonstrate that major psychiatric disorders can be distinguished at the transcript level, and suggest that alternative splicing is one mechanism through which differences in gene expression arise in the brain. Ongoing studies in this sample include experimental validation of differentially expressed genes and transcripts, analysis of co-expression networks, and single-cell RNA sequencing, which will help identify cell-type specific genes and transcripts that are dysregulated in mental illness. We also seek to model the functional genomics of disease-related genes in cells derived from induced pluripotent stem cell (iPSC) lines. This project aims to explore the ways in which we can use iPSC technology to study the biological impact of genes and genetic mutations that we identify in our other ongoing studies. Working with the NIH Center for Regenerative Medicine, the National Institute of Neurological Disorders and Stroke (NINDS) and the National Heart, Lung and Blood Institute (NHLBI) stem cell cores we have so far successfully reprogrammed fibroblasts into iPSCs from 72 AMBiGen participants. We are developing a large iPSC-based resource and associated work-flows that constitute a living catalog of psychiatric risk alleles. iPSC-derived cells are studied with high-resolution microscopic imaging, electrophysiology, and gene expression methods. These data could reveal differences between control and patient-derived cells and the impact of known and novel therapeutic agents. In collaboration with Joseph Steiner (NINDS), we are developing a morphologic assay to measure the effect of known therapeutics and stressors on dendritic number and length following differentiation of NPCs into neurons. We are also exploring ways to measure the functional impact of genetic mutations at the cellular level and to use genome editing tools such as CRISPR-Cas9 to rescue cellular phenotypes and establish a causal role for specific genetic mutations. In a recently published study (Jiang et al. 2019) we used neural cells from carriers of GWAS-identified common risk alleles on chromosome 3p22 to test the influence of these alleles on gene expression and transcription factor binding. We also explored the impact of widely-used mood stabilizing medications. The results showed that neural cells carrying risk alleles displayed lower baseline expression of a nearby gene, TRANK1, that was rescued by chronic treatment with therapeutic dosages of valproic acid (VPA). In collaboration with NIH Distinguished Scientist Gary Felsenfeld, we demonstrated that a nearby SNP strongly affects binding by the transcription factor, CTCF. Decreased expression of TRANK1 perturbed expression of many genes involved in neural development and differentiation. This proof-of-concept study demonstrates the value of iPSC-based assays for translating even common, low-risk alleles identified by GWAS into novel genetic, neurobiological, and pharmacological insights. Through SNP array screening of cases enrolled in AMBiGen, we have identified a family in which 3 individuals carry a rare duplication event on chromosome 16p11.2 known to confer risk for BD and other illnesses. iPSC lines have been established for all 3 carriers and 3 non-carrier relatives and have been differentiated into neural cells. Transcriptomic analyses indicate that some genes in the duplicated region show increased expression in neurons, but that many other genes are also dysregulated in CNV carriers. Overexpressed genes are enriched for several pathways, including neuronal growth and proliferation, MAP kinase signaling, and cell migration. Ongoing experiments are aimed at testing the hypothesis that MAP kinase inhibitors can ameliorate the morphological changes. If successful, these experiments could form the basis for future collaborations aimed at screening for novel therapeutics. In the coming year, we will collect iPSC lines from additional families. We also plan to apply single-cell sequencing technology to iPSC-derived cells to explore variation in DNA sequence and gene expression across individual cells from the same donor, which can be an important source of variation in human iPSC studies. The above approaches may illuminate factors that contribute to disruption of biological mechanisms during the disease process and provide cell-based assays for high throughput screening for novel therapeutics. Multigenic disorders such as BD pose special challenges for experimental studies, since a single causative mutation is usually not identifiable. Thus we are also studying rare, single-gene disorders whose symptoms overlap with those seen in common mental illnesses. Smith-Magenis syndrome (SMS) is a neurodevelopmental disorder characterized by behavioral abnormalities and disruptions in circadian rhythm. Cells from people living with SMS obtained in collaboration with Ann Smith (NHGRI) have been reprogrammed into iPSCs and differentiated into neurons and other brain cells. We are using these cells to explore the biochemical and molecular characteristics of SMS. Early results suggest that SMS mutations have a major impact on the growth, morphology, and transcriptome of developing neurons. Findings from this study may have relevance to other neuropsychiatric disorders with circadian rhythm disturbances, such as depression and BD. In the coming year, we will continue studies in neural cells derived from people with BD, SMS, and unaffected relatives. If successful, these projects will help unpack the biology behind GWAS results, identify high-risk alleles, and shed new light on how risk alleles act within neural cells to generate biological changes in the brain. The findings may identify new targets that lead to better methods of diagnosis and treatment for mood and anxiety disorders.

NCT00001174 为了更好地解释遗传变异对双相情感障碍 (BD) 大脑生物学的影响，我们正在进行各种功能基因组学研究，包括脑成像、死后脑组织的 RNA 测序以及神经元的细胞表型分析源自诱导多能干细胞。 我们向通过荟萃分析增强神经影像遗传学 (ENIGMA) 脑成像联盟贡献了基因型和成像数据，该联盟汇集了来自世界各地的成像和遗传学数据，生成稳健结果所需的大样本量。此外，我们正在进行的阿米什门诺派双极遗传学研究（AMBiGen，ZIA-MH002843）的参与者被转介通过阿米什连接组研究进行扩散张量成像。神经影像内表型可能揭示常见遗传变异影响精神疾病风险的机制。 我们已经完成了对 200 份死后大脑样本的 RNA 测序，这些样本取自患有或未患有严重精神疾病（BD、精神分裂症和重度抑郁症）的人。这项研究的重点是膝下前扣带皮层，尤其是情绪障碍患者的膝下前扣带皮层。结果说明了大脑表达的转录本的巨大多样性，证明了可以在转录本水平上区分主要的精神疾病，并表明选择性剪接是大脑中产生基因表达差异的一种机制。该样本正在进行的研究包括差异表达基因和转录本的实验验证、共表达网络分析以及单细胞 RNA 测序，这将有助于识别在精神疾病中失调的细胞类型特异性基因和转录本。 我们还寻求对源自诱导多能干细胞（iPSC）系的细胞中疾病相关基因的功能基因组学进行建模。该项目旨在探索如何使用 iPSC 技术来研究我们在其他正在进行的研究中发现的基因和基因突变的生物学影响。迄今为止，我们与 NIH 再生医学中心、国家神经疾病和中风研究所 (NINDS) 以及国家心肺和血液研究所 (NHLBI) 干细胞核心合作，已成功将 72 名 AMBiGen 参与者的成纤维细胞重编程为 iPSC。 我们正在开发一个基于 iPSC 的大型资源和相关工作流程，构成精神疾病风险等位基因的动态目录。 利用高分辨率显微成像、电生理学和基因表达方法研究 iPSC 衍生细胞。这些数据可以揭示对照细胞和患者来源的细胞之间的差异以及已知和新型治疗剂的影响。我们与 Joseph Steiner (NINDS) 合作，正在开发一种形态学测定法，以测量已知治疗方法和应激源对 NPC 分化为神经元后树突数量和长度的影响。我们还在探索在细胞水平上测量基因突变的功能影响的方法，并使用 CRISPR-Cas9 等基因组编辑工具来拯救细胞表型并确定特定基因突变的因果作用。 在最近发表的一项研究中（Jiang et al. 2019），我们使用来自 GWAS 鉴定的染色体 3p22 上常见风险等位基因携带者的神经细胞来测试这些等位基因对基因表达和转录因子结合的影响。我们还探讨了广泛使用的情绪稳定药物的影响。结果表明，携带风险等位基因的神经细胞显示附近基因 TRANK1 的基线表达较低，该基因通过使用治疗剂量的丙戊酸 (VPA) 进行长期治疗而得以恢复。我们与 NIH 杰出科学家 Gary Felsenfeld 合作，证明附近的 SNP 强烈影响转录因子 CTCF 的结合。 TRANK1 表达的减少扰乱了许多涉及神经发育和分化的基因的表达。这项概念验证研究证明了基于 iPSC 的检测方法的价值，可以将 GWAS 识别的常见、低风险等位基因转化为新的遗传、神经生物学和药理学见解。 通过对 AMBiGen 中登记的病例进行 SNP 阵列筛查，我们确定了一个家庭，其中 3 个人在染色体 16p11.2 上携带罕见的重复事件，已知该重复事件会带来 BD 和其他疾病的风险。已为所有 3 名携带者和 3 名非携带者亲属建立了 iPSC 系，并已分化为神经细胞。转录组分析表明，重复区域中的一些基因在神经元中表现出表达增加，但许多其他基因在 CNV 携带者中也出现失调。过度表达的基因在多种途径中富集，包括神经元生长和增殖、MAP 激酶信号传导和细胞迁移。正在进行的实验旨在检验 MAP 激酶抑制剂可以改善形态变化的假设。如果成功，这些实验可以为未来旨在筛选新疗法的合作奠定基础。 来年，我们将从更多家族收集 iPSC 系。我们还计划将单细胞测序技术应用于 iPSC 衍生细胞，以探索来自同一供体的各个细胞之间 DNA 序列和基因表达的变异，这可能是人类 iPSC 研究中变异的重要来源。上述方法可以阐明疾病过程中导致生物机制破坏的因素，并为新疗法的高通量筛选提供基于细胞的测定。 BD 等多基因疾病给实验研究带来了特殊的挑战，因为通常无法识别单个致病突变。因此，我们也在研究罕见的单基因疾病，其症状与常见精神疾病的症状重叠。史密斯-马吉尼斯综合征 (SMS) 是一种神经发育障碍，其特征是行为异常和昼夜节律紊乱。与 Ann Smith (NHGRI) 合作获得的来自 SMS 患者的细胞已被重新编程为 iPSC，并分化为神经元和其他脑细胞。我们正在利用这些细胞来探索 SMS 的生化和分子特征。早期结果表明 SMS 突变对发育中神经元的生长、形态和转录组有重大影响。 这项研究的结果可能与其他昼夜节律紊乱的神经精神疾病有关，例如抑郁症和双相情感障碍。 来年，我们将继续研究来自 BD、SMS 患者和未受影响亲属的神经细胞。如果成功，这些项目将有助于解开 GWAS 结果背后的生物学原理，识别高风险等位基因，并为风险等位基因如何在神经细胞内作用以在大脑中产生生物变化提供新的线索。这些发现可能会确定新的目标，从而找到更好的情绪和焦虑症诊断和治疗方法。