Integrating functional genomics in primary human adipocytes to investigate gene regulatory circuitry for obesogenic cardiovascular traits

将功能基因组学整合到原代人类脂肪细胞中，研究肥胖心血管特征的基因调控电路

• 批准号: 9908159
• 负责人: Kristina Marie Garske
• 金额: $ 3.71万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-04-12 至 2021-04-11
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9908159
• 关键词: Address; Adipocytes; Adipose tissue; Affect; Animal Model; Architecture; Biological Assay; Blood Circulation; Body mass index; Cardiovascular Diseases; Cardiovascular system; Caring; Cause of Death; Chromatin; Chromosome 11; Clinical; Complex; Data; Defect; Detection; Diagnosis; Disease; Dyslipidemias; Economic Burden; Elements; Endocrine; Endocrine Glands; Energy Intake; Energy Metabolism; Environment; Etiology; Exhibits; Gene Expression; Genes; Genetic; Genetic Variation; Genomic approach; Genomics; Genotype; Goals; Haplotypes; Heritability; Homeostasis; Human; Human Genetics; Hypertriglyceridemia; Impairment; In Vitro; Individual; Knowledge; Laboratories; Lead; Link; Lipids; Measurement; Measures; Mediating; Medical; Medical Economics; Metabolic; Metabolic syndrome; Mexican; Mission; Molecular; Molecular Genetics; Monounsaturated Fatty Acids; National Heart, Lung, and Blood Institute; Nonesterified Fatty Acids; Nucleic Acid Regulatory Sequences; Obesity; Outcome; Overweight; Pathway interactions; Phenotype; Physiological; Population; Population Heterogeneity; Prevention strategy; Quantitative Trait Loci; RNA Sequences; Regulator Genes; Regulatory Element; Risk; Risk Factors; Serum; Signal Transduction; Single Nucleotide Polymorphism; Stimulus; System; Testing; Transposase; Triglycerides; Variant; biobank; cardiovascular disorder risk; cardiovascular risk factor; clinical phenotype; clinically significant; cohort; differential expression; functional genomics; gene function; gene interaction; genome wide association study; genomic data; human subject; improved; lipid disorder; lipid metabolism; man; men; metabolic phenotype; obesogenic; phenotypic data; prevent; promoter; response; subcutaneous; trait; transcriptome sequencing; transcriptomics; uptake

ABSTRACT Abnormal serum lipid levels, or dyslipidemias, are risk factors for cardiovascular disease (CVD), the leading cause of death worldwide. The genetic factors underlying serum triglyceride (TG) levels are not well understood, despite this trait exhibiting ~50% heritability. Adipose tissue is an important endocrine organ for lipid homeostasis, and adipocytes are key players in energy intake and expenditure mediated through free fatty acid uptake and TG storage and mobilization. The goal of this project is to improve the current understanding of genomic regulatory mechanisms in gene expression and lipid processing pathways in adipocytes. Aim 1 is targeted to identify serum TG-correlated, adipose-expressed genes that are under local genetic control by expression quantitative trait loci (cis-eQTLs) in the Finnish METabolic Syndrome In Men (METSIM) cohort. We will use promoter Capture Hi-C (pCHi-C) in primary human white adipocytes (HWA) to identify which adipose cis-eQTLs interact with the target gene promoter, as promoter-interacting regions are enriched for regulatory elements. Our preliminary data support this, showing that SNPs in open chromatin within promoter-interacting regions in HWA contribute significantly to the heritability of adipose gene expression and serum TG levels in the METSIM cohort. By further integrating lipid genome-wide association study (GWAS) loci into our analysis, we can find a target gene and underlying mechanism of the GWAS signal. In Aim 2 we will perform RNA- sequencing, pCHi-C, and Assay for Transposase-Accessible Chromatin (ATAC)-seq in primary HWA after treating them with saturated or monounsaturated fatty acids, to investigate the genomic regulatory mechanisms altered in response to lipid challenge. This will facilitate detection of elements mediating gene expression changes, assayed through both pCHi-C and ATAC-seq. We hypothesize that genomic regulatory architecture uncovered in this system can be used across populations. We will thus use our data to examine Mexican-specific regions found to be associated with high serum TGs in our laboratory. One locus on chromosome 11 contains a risk haplotype for both high TGs and increased post-prandial TG levels after a fatty meal. The regulatory circuitry, identified in HWA both before and after lipid challenge, can be highly valuable for understanding how Mexican-specific variation might lead to genetic dysregulation at this locus. Aim 2 will also use the UK Biobank (UKBB) for genotype-by-environment interaction analyses. Many systemic metabolic disturbances that are more likely to be present in obese and overweight individuals involve adipocyte function. The UKBB has so far collected genotypes and deep clinical phenotypes for ~150,000 humans, with measures including BMI, lipids, and other CVD risk factors. We will use BMI as an interaction term to test whether the variants within lipid challenge-responsive regions in primary HWA are more likely to affect TGs in the context of this common obesity measurement. Aims 1 and 2 align with the mission of NHLBI to improve medical care for CVD and dyslipidemia through identification of mechanisms of trait-associated variants in diverse populations.

抽象的 血脂水平异常或血脂异常是心血管疾病 (CVD) 的危险因素，心血管疾病是心血管疾病的主要危险因素。 全世界的死亡原因。血清甘油三酯（TG）水平的遗传因素不太好 尽管这一性状表现出约 50% 的遗传力，但这是可以理解的。脂肪组织是重要的内分泌器官 脂质稳态，脂肪细胞是通过游离脂肪介导的能量摄入和消耗的关键参与者 酸的吸收和TG的储存和动员。该项目的目标是提高当前的理解 脂肪细胞基因表达和脂质加工途径的基因组调控机制。目标 1 是 旨在识别血清 TG 相关的脂肪表达基因，这些基因受局部遗传控制 芬兰男性代谢综合征 (METSIM) 队列中的表达数量性状位点 (cis-eQTL)。我们 将在原代人白色脂肪细胞 (HWA) 中使用启动子 Capture Hi-C (pCHi-C) 来识别哪种脂肪 cis-eQTL 与靶基因启动子相互作用，因为启动子相互作用区域被富集以用于调控 元素。我们的初步数据支持这一点，表明启动子相互作用内开放染色质中的 SNP HWA 中的区域对脂肪基因表达和血清 TG 水平的遗传性有显着影响 METSIM 队列。通过进一步将脂质全基因组关联研究（GWAS）基因座整合到我们的分析中， 我们可以找到GWAS信号的靶基因和潜在机制。在目标 2 中，我们将执行 RNA- 初级 HWA 中的测序、pCHi-C 和转座酶可及染色质 (ATAC)-seq 检测 用饱和或单不饱和脂肪酸处理它们，以研究基因组调控 机制因脂质挑战而改变。这将有助于检测介导基因的元件 通过 pCHi-C 和 ATAC-seq 检测表达变化。我们假设基因组调控 该系统中发现的架构可以跨人群使用。因此，我们将使用我们的数据来检查 我们的实验室发现墨西哥特定区域与高血清 TG 相关。上的一个位点 11 号染色体含有高 TG 和脂肪摄入后餐后 TG 水平升高的风险单倍型。 一顿饭。在脂质挑战之前和之后在 HWA 中发现的调节回路可能非常有价值 了解墨西哥特有的变异如何导致该位点的遗传失调。目标2将 还使用英国生物库 (UKBB) 进行基因型与环境的相互作用分析。许多全身代谢 肥胖和超重个体更可能出现的紊乱涉及脂肪细胞功能。 UKBB 迄今为止已收集了约 150,000 人的基因型和深层临床表型，并采取了措施 包括 BMI、血脂和其他 CVD 危险因素。我们将使用 BMI 作为交互项来测试是否 原发性 HWA 中脂质挑战响应区域内的变异更有可能影响 TG 这种常见的肥胖测量方法。目标 1 和 2 与 NHLBI 的使命一致，即改善患者的医疗服务 通过鉴定不同人群中性状相关变异的机制来研究心血管疾病和血脂异常。