Regulation of Gene Expression in the anaphylactic Pathway

过敏途径中基因表达的调节

• 批准号: 9899195
• 负责人: HUA HUANG
• 金额: $ 60.5万
• 依托单位: NATIONAL JEWISH HEALTH
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-05-15 至 2023-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9899195
• 关键词: Affinity; Allergic; Anaphylaxis; Antigens; Binding; CRISPR/Cas technology; Cell Degranulation; Child; Chromatin; Complex; DNA-Directed RNA Polymerase; Data; Developed Countries; Development; Disease; Enhancers; Enzymes; Food; Food Hypersensitivity; GATA2 transcription factor; Gene Expression; Gene Expression Regulation; Genes; Genetic Transcription; Goals; Histamine; Histidine Decarboxylase; Human; IgE; IgE Receptors; In Vitro; Incidence; Inflammation Mediators; Knowledge; Maintenance; Mediating; Mediator of activation protein; Methods; Molecular; Mus; Pathway interactions; Phosphotransferases; Play; Predisposition; Proteins; Regulation; Rest; Role; Severities; Signal Transduction; Signaling Molecule; Skin; Sp1 Transcription Factor; Surface; Testing; Umbilical Cord Blood; Validation; base; caspase 14; crosslink; effective intervention; experimental study; genetic variant; histone modification; in vivo; innovation; innovative technologies; mRNA Expression; mast cell; prevent; promoter; recruit; response; therapy development; transcription factor

Project Summary This proposal investigates the regulation of three selected genes that encode proteins that are critical for anaphylaxis that is mediated by IgE and mast cells (MCs). MCs release inflammatory mediators, including histamine, in response to antigen crosslinking of the IgE/FceRI complex; these mediators play a major role in causing IgE-mediated anaphylactic shock. Although much is known about the proteins that are involved in MC activation, signal transduction and mediator synthesis, little is known about how the genes that encode these critical proteins are regulated. We and others have demonstrated that the transcription factors (TFs) GATA2 and MITF are essential for MC development and maintenance. However, it remains largely unexplored how these and additional TFs interact with their target enhancers to regulate the expression of target genes that are important in mediating histamine synthesis, MC activation, and IgE-mediated disorders, including anaphylaxis and food allergy. Our long-term goal is to enhance fundamental understanding of the regulation of MC genes that influence food allergy susceptibility and severity. Our central hypothesis is that GATA2 and MITF detect MC activation signals, induce chromatin accessibility in genes essential in the anaphylactic pathway, and recruit other TFs to form a promoter/enhancer transcription complex that activates Hdc gene transcription in a switch-like manner (Hdc encodes histidine decarboxylase, the rate limiting enzyme in histamine synthesis). This central hypothesis is strongly supported by our preliminary data and will be tested in 3 aims that are conceptually innovative and make use of innovative technology. In Aim 1, we will determine how the TFs GATA2, MITF, MECOM and their target promoters and enhancers regulate the expression of Hdc and two other genes that are essential in the IgE/MC-mediated anaphylactic pathway: Fcer1a, which encodes the IgE- binding chain of the high affinity IgE receptor, and Pi3p85, which encodes the P85 regulatory chain of PI3K kinase, a signaling molecule required for MC degranulation. In Aim2, we will identify the enhancers and their associated TFs that regulate these genes in humans. In Aim3, we will analyze the function of Hdc enhancers in IgE/MC-mediated anaphylaxis. Upon completion of the planned studies, we will understand substantially more about the mechanisms through which MCs mediate anaphylaxis in both mouse and human. The acquired knowledge should promote understanding of gene regulation in general and the regulation of genes that influence food allergy susceptibility and severity in particular. As a result, these studies should promote the development of effective interventions to prevent and treat food allergy and other IgE-mediated allergic disorders.

项目摘要 这项提案调查了三个选定的基因的调控，这些基因编码的蛋白质对 由IgE和肥大细胞(MC)介导的过敏反应。MCS释放炎症介质，包括 组胺，作为对IgE/FceRI复合体抗原交联的反应；这些介质在 引起IgE介导的过敏性休克。尽管人们对MC中涉及的蛋白质了解很多 激活、信号转导和介体合成，人们对这些基因如何编码知之甚少 关键蛋白质是受调控的。我们和其他人已经证明了转录因子(TF)GATA2 和MITF对于MC的开发和维护是必不可少的。然而，它在很大程度上仍然没有被探索 这些和额外的转录因子与它们的靶增强子相互作用，调节靶基因的表达 在组胺合成、MC激活和包括过敏反应在内的IgE介导的疾病中起重要作用 和食物过敏。我们的长期目标是加强对MC基因调控的基本了解 这会影响食物过敏的敏感性和严重程度。我们的中心假设是GATA2和MITF检测到 MC激活信号，诱导在过敏途径中必不可少的基因的染色质可及性，以及 招募其他转录因子形成启动子/增强子转录复合体，激活HDC基因转录 开关方式(HDC编码组氨酸脱羧酶，组胺合成中的限速酶)。 这一中心假设得到了我们初步数据的有力支持，并将在以下三个目标中进行测试 在概念上创新，并利用创新技术。在目标1中，我们将确定TF如何 GATA2、MITF、Mecom及其靶向启动子和增强子调控HDC和2 在IgE/MC介导的过敏反应途径中至关重要的其他基因：Fcer1a，它编码IgE- 高亲和力IgE受体结合链和编码PI3K P85调节链的Pi3p85 一种MC脱颗粒所需的信号分子。在AIM2中，我们将确定增强剂及其 调节人类这些基因的相关转录因子。在Aim3中，我们将分析HDC增强子在 IgE/MC介导的过敏反应。当计划中的研究完成后，我们将会了解更多。 关于MC介导小鼠和人类过敏反应的机制。被收购的 知识应该促进对基因调控的总体理解，以及对 特别是对食物过敏敏感性和严重程度的影响。因此，这些研究应该会促进 预防和治疗食物过敏和其他IgE介导性过敏的有效干预措施的发展 精神错乱。