Regulation of Gene Expression in the anaphylactic Pathway

过敏途径中基因表达的调节

• 批准号: 10399425
• 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 2024-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10399425
• 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 过敏反应是由IgE和肥大细胞（MC）介导的。MC释放炎症介质，包括 组胺，响应于IgE/FceRI复合物的抗原交联;这些介质在 引起IgE介导的过敏性休克。尽管我们对参与MC的蛋白质有很多了解， 激活，信号转导和介体合成，很少有人知道如何编码这些基因 关键的蛋白质被调节。我们和其他人已经证明，转录因子（TF）GATA 2 和MITF是MC开发和维护所必需的。然而，它仍然在很大程度上未探索如何 这些和另外的TF与它们的靶增强子相互作用以调节靶基因的表达， 在介导组胺合成、MC活化和IgE介导的疾病（包括过敏反应）中起重要作用 食物过敏。我们的长期目标是加强对MC基因调控的基本理解 影响食物过敏敏感性和严重性。我们的中心假设是GATA 2和MITF检测到 MC激活信号，诱导过敏途径中必需基因的染色质可及性， 募集其他TF以形成启动子/增强子转录复合物，该复合物激活Hdc基因转录， 开关样方式（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3个目标中进行测试： 概念创新，并利用创新技术。在目标1中，我们将确定TF GATA 2、MITF、MECOM及其靶向启动子和增强子调控Hdc的表达， 在IgE/MC介导的过敏途径中必不可少的其他基因：Fcer 1a，其编码IgE- 高亲和力IgE受体的结合链，以及编码PI 3 K的P85调节链的Pi 3 p85 激酶，MC脱粒所需的信号分子。在目标2中，我们将确定增强子及其 与调节人类这些基因的转录因子相关。在Aim 3中，我们将分析Hdc增强子在细胞中的功能。 IgE/MC介导的过敏反应。当计划中的研究完成后，我们会有更多的了解 关于MCs介导小鼠和人类过敏反应的机制。所获取的 知识应促进对基因调控的一般理解和对基因的调控， 特别是影响食物过敏敏感性和严重性。因此，这些研究应促进 开发有效的干预措施，以预防和治疗食物过敏和其他IgE介导的过敏性疾病 紊乱