Epigenetic Mechanisms of Chronic Stress Action

慢性应激作用的表观遗传机制

基本信息

批准号：
10583621
负责人：
ERIC J. NESTLER
金额：
$ 67.45万
依托单位：
ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-12-13 至 2027-11-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10583621
关键词：
Adult Affect Anxiety Disorders Applications Grants Autopsy Behavioral Biological Assay Biology Brain Brain region Categories Cells Chromatin Chromatin Structure Chronic stress Cicatrix Clinical Trials DSM-V Data Data Set Depressed mood Development Diagnosis Diagnostic tests Ensure Enzymes Epigenetic Process Exposure to Female Gene Expression Genes Genetic Transcription Genomic Segment Goals Grant Histone H3 Histones Human Individual Investigation Knowledge Laboratories Life Link Malignant Neoplasms Maps Measures Mediating Mediator Mental Depression Methyltransferase Modeling Modification Molecular Molecular Target Motivation Mus National Institute of Mental Health Neurons Nucleus Accumbens Patients Play Post-Traumatic Stress Disorders Predisposition Procedures Proteomics Regulation Research Rewards Role Signal Transduction Stress Stress Tests Testing Time Tissues Viral Weaning Work behavioral response brain reward regions cell type chromatin modification clinically relevant desensitization early life stress expectation gene network genome wide association study genome-wide histone demethylase histone methyltransferase histone modification improved inhibitor innovation insight knock-down male neural next generation sequencing novel overexpression resilience response reward circuitry screening stress disorder stress related disorder stress resilience transcriptome sequencing transcriptomics translational potential

项目摘要

PROJECT SUMMARY: This is a revised version of a new R01 grant that characterizes stable epigenetic changes that are induced in mouse limbic brain regions in response to early life stress (ELS) which then increase an individual's susceptibility to subsequent stress for a lifetime. This work has been supported over the past ten years by an NIMH Conte Center, however, that Center has now “sun-setted”—it cannot be renewed—hence, this new proposal to continue this original line of research. Our innovative hypothesis is that ELS induces stable “chromatin scars” that drive long-lived changes in gene expression, which then mediate downstream changes in cell and circuit function and ultimately behavioral responses to chronic stress in adulthood. We concentrate on nucleus accumbens (NAc) based on its central role in brain reward and motivation and on empirical findings of its central role in controlling stress susceptibility. We utilize open-ended, unbiased proteomic and next- generation sequencing approaches to first identify the most robust and significant putative chromatin scars in NAc in a cell-type-specific manner and to then characterize those mechanisms at the molecular, cellular, and behavioral levels. Importantly, we investigate only those mechanisms that are validated in postmortem NAc of depressed humans. One major focus is H3K79me2 (dimethylation of Lys79 of histone H3), the induction of which is the most significant histone modification caused by ELS in NAc of both male and female mice. The methyltransferase (DOT1L) and demethylase (KDM2B) that control H3K79me2 are both induced in NAc by ELS, effects specific to D2-type medium spiny neurons (MSNs). Bidirectional viral-mediated manipulation of DOT1L or KDM2B selectively in D2 NAc MSNs of male and female mice establishes the role played by these enzymes in mediating the ability of ELS to increase stress susceptibility based on rapid behavioral screening assays. We will now extend measures of stress susceptibility to numerous, more sophisticated behavioral procedures with greater translational potential, and test the ability of a DOT1L inhibitor, now in clinical trials for certain cancers, to reverse ELS-induced stress susceptibility upon systemic administration, further promoting the translational potential of the proposed research. As well, we have shown by RNAseq that DOT1L overexpression in D2 MSNs mimics a large portion of gene expression changes induced by ELS in this cell type, while DOT1L knockdown blocks ELS action. We will now map H3K79me2 enrichment genome-wide in D2 MSNs by CUT&RUNseq to identify networks of genes whose altered expression by ELS is mediated by this histone mark. We will also generate more complete open-ended proteomic and transcriptomic datasets and characterize additional putative chromatin scars induced in NAc by ELS. Substantial preliminary data, for example, implicate H3K27me1 as a prominent chromatin scare that predominates in D1 MSNs of male mice only. Together, this work will characterize novel mechanisms that drive a persisting state of enhanced stress susceptibility and offer insight into new ways of reversing such susceptibility in adulthood.

项目概要：这是新 R01 资助的修订版本，其特征在于诱导的稳定表观遗传变化小鼠边缘大脑区域对早期生活压力（ELS）做出反应，从而增加个体的这项工作在过去十年中得到了一个人的支持。然而，NIMH Conte 中心现在已经“日落”了——它无法更新——因此，这个新的中心我们的创新假设是，ELS 会诱导稳定。 “染色质疤痕”驱动基因表达的长期变化，然后介导下游变化我们专注于细胞和回路功能以及最终对成年期慢性压力的行为反应。基于伏隔核 (NAc) 在大脑奖赏和动机中的核心作用以及实证研究结果我们利用开放式、公正的蛋白质组学和下一步技术来了解其在控制应激敏感性方面的核心作用。世代测序方法首先识别最强大和最显着的假定染色质疤痕 NAc 以细胞类型特异性的方式进行，然后在分子、细胞和重要的是，我们只研究那些在死后 NAc 中得到验证的机制。抑郁症患者的一个主要关注点是 H3K79me2（组蛋白 H3 的 Lys79 二甲基化），即诱导这是 ELS 在雄性和雌性小鼠的 NAc 中引起的最显着的组蛋白修饰。控制 H3K79me2 的甲基转移酶 (DOT1L) 和去甲基化酶 (KDM2B) 均在 NAc 中被诱导 ELS，对 D2 型中型多棘神经元 (MSN) 的双向病毒介导的操纵具有特异性。 DOT1L 或 KDM2B 选择性地存在于雄性和雌性小鼠的 D2 NAc MSN 中，确定了它们所发挥的作用基于快速行为筛选的酶介导 ELS 增加应激敏感性的能力我们现在将压力敏感性的测量扩展到许多更复杂的行为。具有更大转化潜力的程序，并测试 DOT1L 抑制剂的能力，目前正在进行临床试验某些癌症，在全身给药后逆转 ELS 诱导的应激敏感性，进一步促进拟议研究的转化潜力此外，我们还通过 RNAseq 证明了 DOT1L。 D2 MSN 中的过表达模拟了该细胞中 ELS 诱导的大部分基因表达变化类型，而 DOT1L 敲除会阻止 ELS 作用，我们现在将在全基因组范围内绘制 H3K79me2 富集图谱。 CUT&RUNseq 的 D2 MSN，用于识别由 ELS 介导的表达改变的基因网络我们还将生成更完整的开放式蛋白质组和转录组数据集和表征 ELS 在 NAc 中诱导的额外假定染色质疤痕。例如，暗示 H3K27me1 是雄性小鼠 D1 MSN 中占主导地位的显着染色质恐慌总之，这项工作将描述驱动持续增强压力状态的新机制。并提供了对在成年期扭转这种易感性的新方法的见解。