Gene regulatory circuitry underlying the dynamic control of glucocorticoid signaling

糖皮质激素信号传导动态控制的基因调控电路

• 批准号: 9978850
• 负责人: JAMES A COFFMAN
• 金额: $ 8.3万
• 依托单位: MOUNT DESERT ISLAND BIOLOGICAL LAB
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-17 至 2021-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9978850
• 关键词: Address; Adult; Adverse effects; Anti-Inflammatory Agents; Appearance; Binding; Blood Cells; Brain; Cells; Chromatin; Chronic; Chronic stress; Cytoplasm; Data; Development; Dose; Drug Targeting; Embryo; Epitopes; Feedback; Foundations; Future; Gene Expression; Gene Expression Regulation; Genes; Genetic Transcription; Genomics; Glucocorticoid Receptor; Glucocorticoids; Goals; Health; High-Throughput Nucleotide Sequencing; Hippocampus (Brain); Homeostasis; Hormones; Human; Hydrocortisone; Immune system; Immunologics; Inflammation; Joints; Knowledge; Kruppel-like transcription factors; Laboratories; Larva; Literature; Long-Term Effects; Metabolic syndrome; Metabolism; Molecular Chaperones; Molecular Genetics; Mus; Nervous system structure; Neurosecretory Systems; Pathology; Pathway interactions; Pharmaceutical Preparations; Physiologic pulse; Physiological; Physiology; Play; Promoter Regions; Proteins; Regulation; Regulator Genes; Reporting; Research; Research Project Grants; Resistance; Role; Signal Transduction; Steroids; Stress; Testing; Time; Transcription Regulatory Protein; Up-Regulation; Work; Zebrafish; base; body system; chromatin immunoprecipitation; circadian; experimental study; glucocorticoid receptor alpha; innovation; obesity development; overexpression; pediatric trauma; prevent; receptor function; response to injury; side effect; stem; steroid hormone; tool; transcription factor

PROJECT SUMMARY / ABSTRACT Glucocorticoids (e.g. cortisol) are stress-induced and circadian-regulated steroid hormones that regulate gene expression by binding to and thus activating the Glucocorticoid Receptor (GR) transcription factor. Glucocorticoid-responsive gene regulation is highly dynamic, requiring multiple levels of dynamic control mechanisms that are critical for healthy development and physiology. Glucocorticoid signaling plays a central role in regulating inflammation, and synthetic glucocorticoids are widely prescribed as anti-inflammatory drugs. However, their extended use has many unhealthy side effects, similar to the adverse health effects of chronic stress, which is due at least in part to the loss of dynamic control resulting from the chronicity of the exposure. The intracellular and molecular-genetic mechanisms that control the dynamics of glucocorticoid responsive gene activity remain poorly understood. This project will address that knowledge gap, focusing on klf9, a GR target gene that encodes a ubiquitously-expressed transcription factor with important roles in the nervous and immune systems, which has recently been implicated in chronic stress-induced pathology. Based on our preliminary data and the available literature we hypothesize that Klf9 functions as a GR-activated feedforward repressor to enforce transient and/or circadian expression of a subset of GR-target genes, including itself and the GR antagonist fkbp5. We will test that hypothesis in zebrafish by assessing the role of Klf9 in the dynamic control of GC-responsive gene expression, by comparing expression dynamics of fkbp5, klf9, and other GR target genes in larvae of wild-type zebrafish and a Klf9-deficient line that we have recently produced (Specific Aim 1). In addition, we will introduce an epitope tag sequence into the klf9 locus (Specific Aim 2), which will facilitate future experiments aimed at identifying direct Klf9-target genes by chromatin immunoprecipitation and high throughput sequencing (ChIP-seq), and in combination with strains that we have already generated that lack a functional GR and in which the GR is epitope tagged, comprehensively identify the set of genes that is jointly regulated by the GR and Klf9. The project will thus determine whether Klf9 is a critical node in the gene regulatory network underlying dynamic control of GR-responsive gene expression, and provide a foundation for future research that will systematically elucidate the broader developmental and neuroendocrine functionality of klf9 with respect to glucocorticoid-responsive gene regulation.

项目摘要 /摘要 糖皮质激素（例如皮质醇）是压力诱导的昼夜节律类固醇激素，可调节基因 通过与糖皮质激素受体（GR）转录因子结合并因此激活表达。 糖皮质激素反应性基因调节是高度动态的，需要多个动态控制 对于健康发展和生理学至关重要的机制。糖皮质激素信号的中心作用 在调节炎症和合成糖皮质激素中的作用被广泛规定为抗炎药。 但是，它们的扩展使用具有许多不健康的副作用，类似于慢性健康的不良健康影响 应力，至少部分是由于暴露的慢性导致动态控制的丧失。 控制糖皮质激素反应动力学的细胞内和分子遗传学机制 基因活性仍然知之甚少。该项目将解决该知识差距，重点是KLF9 靶基因编码普遍表达的转录因子，在神经和 免疫系统最近与慢性应激诱导的病理有关。基于我们 初步数据和可用文献我们假设KLF9起着GR激活的馈电。 强制执行瞬时和/或昼夜节律的gr靶基因的表达，包括本身， GR拮抗剂FKBP5。我们将通过评估KLF9在动态中的作用来检验斑马鱼中的假设 通过比较FKBP5，KLF9和其他GR的表达动力学来控制GC响应基因表达 野生型斑马鱼幼虫中的靶基因和我们最近产生的KLF9缺陷线（具体 目标1）。此外，我们将在KLF9基因座（特定AIM 2）中引入一个表位标签序列，这将 促进未来的实验，旨在通过染色质免疫沉淀和 高吞吐量测序（芯片seq），并与我们已经生成的菌株结合 缺乏功能性的GR，其中GR被标记为表位，全面识别了一组是 由GR和KLF9共同监管。因此，该项目将确定KLF9是否是基因中的关键节点 GR响应基因表达的动态控制的基础调节网络，并为 未来的研究将系统阐明更广泛的发育和神经内分泌功能 KLF9相对于糖皮质激素反应性基因调节。