Translational genomics in gout: From GWAS signal to mechanism

痛风的转化基因组学：从 GWAS 信号到机制

• 批准号: 10735151
• 负责人: TONY R MERRIMAN
• 金额: $ 60.56万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-21 至 2028-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10735151
• 关键词: Acute; Address; Adult; Affect; African American; Alabama; Ankylosing spondylitis; Architecture; Area; Biological Assay; CTLA4-Ig; Candidate Disease Gene; Cardiometabolic Disease; Cell Line; Cells; Chromosome Structures; Chromosomes, Human, 6-12 and X; Clinical; Code; Consent; DNA Methylation; Deposition; Development; Drug Targeting; Enhancers; Epigenetic Process; Family; Flare; Future; Gene Expression; Gene Expression Regulation; Genes; Genetic; Genetic Processes; Genetic Transcription; Genetic study; Genomics; Genotype; Gout; Health; Hematopoiesis; Hi-C; Human; Human Cell Line; Hyperuricemia; Immune; Immune response; Immunity; Individual; Inflammasome; Inflammation; Inflammatory; Inflammatory Response; Injections; Innate Immune System; International; Joints; Knock-out; Knowledge; Larva; Leukocytes; Link; Macrophage; Mediating; Metabolism; Methylation; Modeling; Modification; Molecular; Molecular Conformation; Molecular Genetics; Nucleic Acid Regulatory Sequences; Participant; Pathway interactions; Persons; Population; Predisposition; Process; Production; Proteins; RNA Binding; Regulation; Research; Research Design; Resources; Rheumatoid Arthritis; Role; Secondary to; Severities; Signal Transduction; Site; Stimulus; System; Testing; Therapeutic; Training; Translating; Translations; Untranslated RNA; Urate; Variant; Work; Zebrafish; candidate identification; caucasian American; cell type; chromatin isolation by RNA purification sequencing; comorbidity; drug development; druggable target; epigenome; epigenomics; experience; follow-up; gene conservation; genetic association; genetic variant; genome wide association study; genomic locus; histone modification; immunoregulation; improved; innovation; insight; knock-down; locked nucleic acid; monocyte; neutrophil; new therapeutic target; novel; novel strategies; overexpression; physical symptom; prevent; promoter; psychologic; recruit; response; risk variant; screening; social; targeted treatment; transcriptome; transcriptome sequencing; translational genomics; validation studies; volunteer

SUMMARY Gout is prevalent in the US (3.9% of the adult population) and not only directly impacts peoples’ lives but is also co-morbid with cardiometabolic disease. Gout consists of unpredictable episodes of acute inflammation or flares resulting from monocyte NLRP3 inflammasome activation by monosodium urate (MSU) crystals in people with hyperuricemia, the subsequent production of IL-1, and recruitment of large numbers of inflammatory cells into the affected joint. Epigenetic reprogramming and altered gene transcription in response to elevated levels of soluble urate are mechanisms of this enhanced cellular reactivity to the secondary stimuli, known as innate trained immunity. To better understand the factors controlling the progression from hyperuricemia to gout we have completed a very large genome-wide association study (GWAS) in gout, identifying several hundred gout-associated loci. Loci include long-noncoding RNAs (lncRNAs) that have diverse functions including regulation of gene expression, deposition of epigenetic modifications and organization of chromosome architecture. Some are immune gene-priming lncRNAs (IPLs) that direct transcriptional machinery over multiple promoters. From these loci we have identified one key causal pathway (clonal hematopoiesis of indeterminate potential (CHIP)) for which we will study the molecular genetic processes controlling its activation. The CHIP pathway is involved in control of the epigenome - DNA methylation, histone modification and metabolism of substrates. It may make people more susceptible to gout by causing the innate immune system to be hyper-responsive to MSU crystals. We hypothesize that the genetic loci identified from the gout GWAS control activity of this pathway by regulation of gene expression, including through regulation of the epigenome. In testing this hypothesis, in three Aims, we will understand the molecular control of the pathway and provide a basis for future studies in targeting this pathway for improved management of gout. In Aim 1 we will use experimental systems, including a zebrafish model of gout, to understand where regulatory regions are expressed and how the gout-associated loci influence NLRP3- inflamasome activation. Zebrafish are translucent, allowing development of innovative models, and there is 82% conservation of genes with humans and functionally equivalent macrophages and neutrophils. In Aim 2 we will compare the transcriptome and epigenome in MSU crystal-stimulated monocytes of individuals with high and low burdens of gout risk alleles in order to gain further insights into the molecular regulation of the pathways, and to identify downstream pathways. Individual genes will be knocked down in a cell line. In Aim 3 we will use our established pipeline to understand how lncRNAs (i.e. IPLs) connect transcriptional machinery to the promoters of innate immune genes at specific loci in the molecular control of activation of the gout flare. Our studies will deepen our knowledge of the mechanisms of gout flares and its genetic basis, and ultimately point to areas of research that may allow for novel treatments in gout.

总结 痛风在美国很普遍（占成年人口的3.9%），不仅直接影响人们的生活， 也与心脏代谢疾病共病。痛风包括不可预测的急性炎症发作或 单核细胞NLRP 3炎性小体激活引起的耀斑，由尿酸盐（MSU）晶体引起， 高尿酸血症的人，随后产生IL-1 β，并招募大量的 炎症细胞进入受影响的关节。表观遗传重编程和基因转录的改变 可溶性尿酸盐水平升高是这种增强的细胞对次级刺激的反应性的机制， 被称为先天训练免疫。为了更好地了解控制从 高尿酸血症与痛风我们已经完成了一项非常大的痛风全基因组关联研究（GWAS）， 鉴定了几百个痛风相关的基因座。基因座包括长链非编码RNA（lncRNA）， 多种功能，包括基因表达的调节，表观遗传修饰的沉积， 染色体结构的组织有些是免疫基因启动lncRNA（IPL）， 转录机器上的多个启动子。从这些基因座中，我们已经确定了一个关键的致病途径 （克隆造血的不确定潜力（CHIP）），我们将研究分子遗传学 控制其激活的过程。CHIP通路参与表观基因组DNA的控制 甲基化、组蛋白修饰和底物代谢。它可能使人们更容易患痛风 通过引起先天免疫系统对MSU晶体的高度反应。我们假设 从痛风GWAS鉴定的遗传基因座通过基因表达的调节来控制该途径的活性， 包括通过调节表观基因组。在测试这一假设时，在三个目标中，我们将了解 分子控制的途径，并提供了基础，为今后的研究，针对这一途径，以改善 痛风的治疗在目标1中，我们将使用实验系统，包括痛风的斑马鱼模型， 了解调控区域的表达以及痛风相关基因座如何影响NLRP 3- 炎性小体激活。斑马鱼是半透明的，允许开发创新模型， 人类和功能等同的巨噬细胞和中性粒细胞的基因保守性为82%。在目标2 我们将比较MSU晶体刺激的个体单核细胞中的转录组和表观基因组， 痛风风险等位基因的高和低负担，以便进一步了解痛风的分子调控。 #21453;的途径，并确定下游途径。单个基因将在细胞系中被敲除。目标3 我们将使用我们建立的管道来了解lncRNA（即IPL）如何连接转录机制， 与痛风发作激活的分子控制中特定位点的先天免疫基因启动子有关。 我们的研究将加深我们对痛风发作机制及其遗传基础的认识， 指出研究领域可能允许新的治疗痛风。