A role for endogenous retroelements in Aicardi-Goutieres Syndrome

内源性逆转录因子在 Aicardi-Goutieres 综合征中的作用

基本信息

批准号：
9296176
负责人：
JOHN Lawrence GOODIER
金额：
$ 20.43万
依托单位：
JOHNS HOPKINS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-06-14 至 2019-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9296176
关键词：
17 year old ADAR1 Address Affect Algorithmic Analysis Amyotrophic Lateral Sclerosis Antigens Autoantibodies Autoimmune Process Awareness Basal Ganglia Bioinformatics Biological Assay Blood Brain Calcium Cause of Death Cell Line Cells Cerebrospinal Fluid Cessation of life Childhood Complementary DNA Crows DNA DNA Sequencing Facility Data Deposition Disease Disease Progression Electronic Mail Elements Embryonic Development Encephalopathies Endogenous Retroviruses Enzyme-Linked Immunosorbent Assay Fish Proteins Future Gene Proteins Genes Genetic Transcription Genome Genomics Grant High-Throughput Nucleotide Sequencing Human Human Genome Immune response Immune system Immunology Impairment Individual Infection Inflammatory Innate Immune System Insertion Mutation Interferon Type I Interferons Investigation Laboratories Laboratory Study Leukocytes Life Light Link Malignant Neoplasms Mentors Metabolism Molecular Profiling Multiple Sclerosis Mus Mutation Nervous System Trauma Neuraxis Neurons Nucleic Acids Paste substance Pathology Patients Phenotype Postdoctoral Fellow Process Protein Analysis Proteins Protocols documentation Pseudogenes RNA RNA analysis RNA-Directed DNA Polymerase Recruitment Activity Relaxation Research Research Personnel Retroelements Retrotransposition Retrotransposon Retroviridae Reverse Transcription Rheumatism Role Sampling Serum Severities Signal Transduction Skin Somatic Cell Source Systemic Lupus Erythematosus TREX1 gene Teleconferences Testing Tissues Transgenes Variant Work base brain dysfunction brain tissue cell type cohort early childhood early onset experience functional loss human DNA immunocytochemistry in vivo insight interest leukodystrophy mouse model next generation sequencing novel peripheral blood protein expression pseudotoxoplasmosis syndrome public health relevance response skin lesion systemic autoimmune disease transcriptome sequencing transposon/insertion element treatment strategy

项目摘要

DESCRIPTION (provided by applicant): A role for endogenous retroelements in Aicardi-Goutières syndrome Aicardi-Goutières syndrome (AGS) is a severe Mendelian inflammatory disorder that affects particularly the brain and frequently causes death in childhood. The disease is characterized by progressive encephalopathy, psychomotor regression, and lesions of the skin, together with increased levels of Type I interferon in the cerebrospinal fluid and serum, and induction of interferon-stimulated genes detectable in peripheral blood. Causative mutations have been identified in seven genes, TREX1, RNASEH2A, RNASEH2B, RNASEH2C, SAMHD1, ADAR1 and IFIH1, with variation in the severity of their associated phenotypes. The protein products of these genes are involved in RNA metabolism or signaling, and have also been linked with suppression of infecting retroviruses and/or endogenous retrotransposons. This study is based on the hypothesis that functional loss of an AGS-associated gene alters the normal metabolism of retrotransposon RNA or its reverse-transcribed cDNA, triggering an interferon response and AGS. Retrotransposons are mobile DNA elements that duplicate themselves by a "copy and paste" mechanism using an RNA intermediate. Endogenous retroviruses (HERVs) comprise 8% of the human genome. Although no HERVs capable of replication have been identified, ongoing HERV expression has been implicated in several disease conditions, including multiple sclerosis, amyotrophic lateral sclerosis, and autoimmune rheumatic disease. LINE1 (L1) retrotransposons occupy 17% of human DNA, although it is believed that only about 100 remain competent for retrotransposition in any individual. L1 retrotransposition has also been responsible for the insertion of over a million non-autonomous Alu retrotransposons and thousands of processed pseudogenes. The cell has evolved defenses restricting retrotransposition, which are occasionally relaxed in certain somatic cell types, notably neuronal cells in the human brain. We predict relaxation of retroelement expression in AGS patients. Using RNA analyses, immunocytochemistry, and functional assays for reverse transcriptase activity, we will examine brain tissue, blood, sera, and derived cell lines from AGS patients to ascertain if retroelement RNA or protein expression is elevated in the disease state. We will determine if de novo L1 and Alu insertion numbers are increased in tissues of AGS patients using high-throughput sequencing protocols. The question of whether L1 expression can induce an interferon response will be addressed using a mouse model harboring an inducible L1 transgene. Finally, we will develop ELISA assays to ascertain if sera from AGS patients contain autoantibodies directed against retroelement proteins. This research should shed new light on a devastating childhood disease and suggest future strategies for treatment. Furthermore, new insights into the interaction of the intrinsic immune system of the cell and endogenous retroelements will be gained.

描述（由适用提供）：AICARDI-GOUTIères综合征（AGS）中内源性恢复元素的作用是一种严重的Mendelian炎症性疾病，尤其会影响大脑并经常导致童年死亡。该疾病的特征是进行性脑病，精神运动消退和皮肤水平，以及脑脊液和血清中I型干扰素水平的增加，以及在外周血中诱导干扰素刺激的基因。在七个基因，TREX1，RNASEH2A，RNASEH2B，RNASEH2C，SAMHD1，ADAR1和IFIH1中已经鉴定了致病突变，其相关表型的严重程度有所不同。这些基因的蛋白质产物参与RNA代谢或信号传导，并且也与抑制感染逆转录病毒和/或内源性逆转录座子有关。这项研究基于以下假设：AGS相关基因的功能丧失改变了返回跨跨RNA的正常代谢或其反转录的cDNA，从而触发干扰素反应和AG。逆转录子是移动DNA元素，使用RNA中间体通过“复制和粘贴”机制复制自己。内源性逆转录病毒（HERV）占人类基因组的8％。尽管尚未鉴定出能够复制的HERV，但仍在多种疾病疾病中实施了持续的HERV表达，包括多发性硬化症，肌萎缩性侧面硬化症和自身免疫性风湿病。 LINE1（L1）逆转座子占人类DNA的17％，尽管据信只有大约100个在任何个体中仍具有逆转录的能力。 L1逆转录也负责插入超过100万个非自治的Alu逆转录子和数千个加工的假基因。该细胞已经进化出防御限制了逆转录置的限制，这些逆转录置位有时会在某些体细胞类型中放松，是人脑中的神经元细胞。我们预测AGS患者的恢复表达的放松。使用RNA分析，免疫细胞化学和用于逆转录酶活性的功能测定，我们将检查来自AGS患者的脑组织，血液，血清和衍生的细胞系，以确定疾病状态下的retrolement RNA或蛋白质表达是否升高。我们将使用高通量测序方案来确定在AGS患者的时间中，从头L1和ALU插入数量是否增加。 L1表达是否可以诱导干扰素反应的问题将使用具有诱导L1转换的小鼠模型来解决。最后，我们将开发ELISA测定法，以确定来自AGS患者的血清是否含有针对重新元素蛋白的自身抗体。这项研究应该对毁灭性的儿童疾病进行新的启示，并提出未来的治疗策略。此外，将获得对细胞内在免疫系统相互作用和内源性追溯元件的相互作用的新见解。