Genetic regulation and immunological function of ERAP2 haplotypes

ERAP2单倍型的遗传调控和免疫功能

• 批准号: 10470505
• 负责人: Chun Jimmie Ye
• 金额: $ 8.07万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-06-15 至 2023-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10470505
• 关键词: Adaptive Immune System; Affect; Alleles; Amino Acid Sequence; Aminopeptidase; Ankylosing spondylitis; Antigen Presentation; Antigen Presentation Pathway; Antiviral Response; Autoimmune Diseases; Autoimmunity; Biological Assay; Biology; CRISPR/Cas technology; Catalogs; Cell physiology; Cells; Cleaved cell; Clustered Regularly Interspaced Short Palindromic Repeats; Communicable Diseases; Crohn' s disease; Data; Dendritic Cells; Disease; Endoplasmic Reticulum; Environment; Enzymes; Equilibrium; Evolution; Genes; Genetic; Genetic Transcription; Genets; Genomic Imprinting; Genotype; Genotype-Tissue Expression Project; Goals; HIV; Haplotypes; Heterodimerization; Homologous Gene; Human; Immune; Immune response; Immune system; Immunologics; In Vitro; Individual; Influenza; Interferon-beta; Interferons; Lead; Left; Length; Light; Luciferases; Major Histocompatibility Complex; Maps; Mass Spectrum Analysis; Measures; Mediating; Modeling; Modernization; Molecular; Mus; Natural Selections; Nature; Nonsense-Mediated Decay; Peptides; Phenotype; Play; Pre-Eclampsia; Predisposition; Process; Property; Protein Isoforms; Proteins; Proteomics; RNA Splicing; Race; Regulation; Reporter; Rest; Ribosomes; Risk; Role; Science; Single Nucleotide Polymorphism; Site; Specificity; T cell response; T-Lymphocyte; Techniques; Testing; Tissues; Transcript; Transgenic Mice; Translations; Vaccinated; Viral; Viral Antigens; Virus; Virus Diseases; antigen processing; arm; autoimmune pathogenesis; base; cytokine; environmental change; fitness; flu; functional genomics; gene product; genetic variant; genome editing; genomic data; genomic locus; immune function; in vivo; influenza infection; insight; loss of function; lymphoblastoid cell line; monocyte; pathogen genome; response; targeted treatment; tool; transcriptome sequencing

We propose to dissect the genetic control and immunological function of ERAP2, a gene previously shown to play a role in antigen processing. Two haplotypes at the ERAP2 locus have been maintained by natural selection in humans where the more frequent haplotype (Haplotype B) is associated with risk for Crohn's disease, ankylosing spondylitis, preeclampsia and HIV susceptibility. Enigmatically, while Haplotype A encodes a full-length enzyme that cleaves viral peptides for antigen presentation, Haplotype B encodes a transcript efficiently degraded by nonsense-mediated decay. Why would natural selection have maintained a seemingly loss-of-function version of the gene and by what mechanism would it cause disease? We found a possible explanation by studying the antiviral response of monocyte-derived dendritic cells in 250 healthy individuals. In response to in vitro stimulations, influenza infection induced the transcription of two unannotated short isoforms from Haplotype B that are not observed in resting or interferon-beta stimulated cells. This observation, combined with previous immunological results and evidence of natural selection, leads us to hypothesize that the two ERAP2 haplotypes encode distinct gene products that play divergent roles in viral antigen processing and presentation. In this proposal, we will apply state-of-the-art molecular and immunological tools to test this hypothesis. In Aim 1, we will use functional genomic techniques (long-read RNA-seq, ribosomal footprinting and proteomics) to characterize the transcriptional and translational properties of ERAP2 in response to a spectrum of viral challenges. In Aim 2, we will map the cis-genetic control of ERAP2 using reporter assays and CRISPR/Cas9-mediated genome editing. In Aim 3, we will measure how different ERAP2 isoforms affect antigen presentation and T cell function. Our findings will shed new light on the regulation and function of the ERAP2 haplotypes and contribute to the understanding of how genetic variants under natural selection could cause autoimmune disease.

我们建议剖析 ERAP2 的遗传控制和免疫功能，该基因先前已被证明可以 在抗原加工中发挥作用。 ERAP2 基因座上的两个单倍型已被自然维持 在人类中进行选择，其中更频繁的单倍型（单倍型 B）与克罗恩病的风险相关 疾病、强直性脊柱炎、先兆子痫和艾滋病毒易感性。神秘的是，虽然单倍型 A 编码 一种全长酶，可切割病毒肽以进行抗原呈递，单倍型 B 编码转录本 通过无义介导的衰变有效降解。为什么自然选择会保持看似 该基因的功能丧失版本以及它会通过什么机制导致疾病？我们发现了一个可能的 通过研究 250 名健康个体中单核细胞衍生的树突状细胞的抗病毒反应来解释。在 对体外刺激的反应，流感感染诱导了两种未注释的短亚型的转录 来自单倍型 B，在静息或干扰素-β 刺激的细胞中未观察到。这一观察， 结合之前的免疫学结果和自然选择的证据，我们推测 两种 ERAP2 单倍型编码不同的基因产物，在病毒抗原加工中发挥不同的作用 和演示。在本提案中，我们将应用最先进的分子和免疫学工具来测试这一点 假设。在目标 1 中，我们将使用功能基因组技术（长读长 RNA-seq、核糖体足迹 和蛋白质组学）来表征 ERAP2 响应的转录和翻译特性 一系列病毒挑战。在目标 2 中，我们将使用报告基因分析绘制 ERAP2 的顺式遗传控制图谱，并 CRISPR/Cas9 介导的基因组编辑。在目标 3 中，我们将测量不同 ERAP2 异构体如何影响 抗原呈递和 T 细胞功能。我们的研究结果将为我们的监管和功能提供新的线索 ERAP2 单倍型并有助于理解自然选择下的遗传变异如何发挥作用 引起自身免疫性疾病。