Genetic enhancement of CREB signaling in Rett Syndrome

Rett 综合征中 CREB 信号传导的遗传增强

基本信息

批准号：
10227232
负责人：
Randal Scot Tibbetts
金额：
$ 19.44万
依托单位：
UNIVERSITY OF WISCONSIN-MADISON
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-08-01 至 2023-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10227232
关键词：
Aging Alleles Alzheimer&apos s Disease Behavior Behavioral Binding Binding Proteins Binding Sites CREBBP gene CRISPR/Cas technology Cells ChIP-seq Complex Cyclic AMP Cyclic AMP-Dependent Protein Kinases Cyclic AMP-Responsive DNA-Binding Protein DNA Binding DNA-Binding Proteins Defect Disease Disease Progression Exhibits Female Gene Expression Gene Expression Profiling Gene Mutation Gene Proteins Genes Genetic Enhancement Genetic Transcription Goals Huntington Disease Hyperactivity Impaired cognition Induced pluripotent stem cell derived neurons Knock-in Mouse Knockout Mice Laboratories Link Malignant Neoplasms Mediating Memory Metabolic Diseases Metabolism Methyl-CpG-Binding Protein 2 Modeling Molecular Mouse Strains Mus Mutant Strains Mice Mutation Neurodegenerative Disorders Neurodevelopmental Disorder Neurons Nuclear Import Pharmacology Phosphodiesterase Inhibitors Phosphorylation Physiological Play Pluripotent Stem Cells Protein Kinase Protein Subunits Protein phosphatase Proteins Regulation Reporting Research Rett Syndrome Role Second Messenger Systems Signal Transduction Signaling Protein Stimulus Synaptic Transmission Testing Therapeutic Transcription Coactivator Transcription Repressor Up-Regulation Work age related attenuation autism spectrum disorder behavioral study causal variant cell growth cell growth regulation disease phenotype experimental study gene function genetic approach genetic testing genome-wide in vivo insight loss of function male mouse model mutant nervous system disorder neurophysiology novel protein expression protein function recruit therapeutic target tool transcription factor tumorigenesis

项目摘要

Project Summary The goal of this R21 project is to test whether enhancement of endogenous CREB (cAMP response element binding protein) signaling ameliorates disease phenotypes in a mouse model of the autism spectrum disorder, Rett syndrome (RTT). CREB is an evolutionarily conserved transcription factor that executes critical roles in metabolism, neuronal synaptic transmission, and cell growth regulation. Upregulation of CREB signaling has been linked to cancer and metabolic disease whereas reductions in CREB signaling are associated with age- dependent cognitive decline and a host of neurodegenerative disorders, including Alzheimer’s Disease, Huntington’s Disease and, of particular relevance to this proposal, RTT. CREB is activated by the second messenger cAMP through a two-hit mechanism involving its phosphorylation on S133 by protein kinase A (PKA), which recruits the transcriptional coactivator CREB-binding protein (CBP), and PKA-dependent nuclear import of CRTC proteins (cAMP/Ca2+-regulated transcriptional coactivators), which stabilize CREB-DNA interactions. We recently discovered that the critical S133 residue is dephosphorylated by protein phosphatase 2A (PP2A), which is recruited to CREB through short linear motifs (SLiMs) that are recognized by B56-type PP2A targeting subunits. Mutation of B56 binding sites in CREB strongly potentiated basal and stimulus dependent S133 phosphorylation and CREB transcriptional potential, informing a strategy for the genetic enhancement of CREB signaling in vivo. To this end, we used CRISPR/CAS9 to introduce a conservative E153D mutation that abolished B56-PP2A binding into the mouse Creb gene. Cells from homozygous CrebE153D mice exhibited increased S133 phosphorylation and upregulation of CREB-dependent gene expression, supporting further study of CrebE153D mice as a model for hypermorphic CREB signaling. In this study we will test whether CREB hyperactivation can reverse behavioral defects in a mouse model of RTT, a devastating neurodevelopmental disordered caused by X-linked mutations in the transcriptional repressor methyl-CpG binding protein (MeCP2). Previous work from the Chang laboratory revealed that CREB expression and S133 phosphorylation were downregulated in Mecp2- mutant neurons and that pharmacologic activators of CREB signaling partially reversed behavioral defects in Mecp2+/- mice. These findings set the stage for this proposal where we will use CrebE153D mice to test whether enhancement of endogenous CREB activity is sufficient for behavioral rescue in the RTT mouse model. The objectives of the proposal are to: (i) test the effect of CREB hyperphosphorylation on disease progression in male and female Mecp2 knockout (KO) mice; and (ii) determine impacts of B56-PP2A-CREB signaling on neuronal gene expression. In addition to testing genetic interaction between Creb and Mecp2, these studies, will define physiologic implications of the PP2A-B56-CREB signaling axis and develop the CrebE153D model as a tool for manipulating endogenous CREB signaling in other physiologic paradigms.

项目概要该R21项目的目标是测试内源性CREB（cAMP反应元件）的增强是否结合蛋白）信号改善自闭症谱系障碍小鼠模型的疾病表型， Rett 综合征 (RTT) 是一种进化上保守的转录因子，在 CREB 信号传导的上调具有代谢、神经元突触传递和细胞生长调节的作用。与癌症和代谢疾病有关，而 CREB 信号传导的减少与年龄相关依赖性认知能力下降和一系列神经退行性疾病，包括阿尔茨海默病，亨廷顿舞蹈症以及与本提案特别相关的 CREB 由第二个激活。信使 cAMP 通过两次打击机制，涉及其在 S133 上被蛋白激酶 A (PKA) 磷酸化，它募集转录共激活因子 CREB 结合蛋白 (CBP) 和 PKA 依赖性核输入 CRTC 蛋白（cAMP/Ca2+ 调节的转录共激活因子），可稳定 CREB-DNA 相互作用。我们最近发现关键的 S133 残基被蛋白磷酸酶 2A (PP2A) 去磷酸化，通过 B56 型 PP2A 靶向识别的短线性基序 (SLiM) 被招募到 CREB CREB 中 B56 结合位点的突变强烈增强基础和刺激依赖性 S133。磷酸化和 CREB 转录潜力，为 CREB 遗传增强策略提供信息为此，我们使用 CRISPR/CAS9 引入了保守的 E153D 突变，从而废除了该突变。 B56-PP2A 与小鼠 Creb 基因结合，来自纯合 CrebE153D 小鼠的细胞表现出 S133 增加。 CREB 依赖性基因表达的磷酸化和上调，支持 CrebE153D 的进一步研究小鼠作为超形态 CREB 信号传导的模型。在这项研究中，我们将测试 CREB 过度激活是否可以逆转小鼠模型的行为缺陷 RTT，一种由转录抑制因子 X 连锁突变引起的破坏性神经发育障碍 Chang 实验室之前的工作揭示了 CREB 的表达。和 S133 磷酸化在 Mecp2 突变神经元中下调，并且药物激活剂 CREB 信号传导部分逆转了 Mecp2+/- 小鼠的行为缺陷。这些发现为此奠定了基础。建议我们使用 CrebE153D 小鼠来测试内源性 CREB 活性的增强是否是足以在 RTT 小鼠模型中进行行为救援该提案的目的是：（i）测试效果。 CREB 过度磷酸化对雄性和雌性 Mecp2 敲除 (KO) 小鼠疾病进展的影响；以及 (ii) 除了测试遗传之外，还确定 B56-PP2A-CREB 信号传导对神经元基因表达的影响。 Creb 和 Mecp2 之间的相互作用，这些研究将定义 PP2A-B56-CREB 的生理学意义信号轴并开发 CrebE153D 模型作为在其他疾病中操纵内源性 CREB 信号传导的工具生理学范式。