Using epigenome editing of transcriptional enhancers to regulate adult visual cortical plasticity

利用转录增强子的表观基因组编辑来调节成人视觉皮层可塑性

• 批准号: 10385236
• 负责人: LINDSEY L GLICKFELD
• 金额: $ 20.13万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-03-01 至 2024-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10385236
• 关键词: Adult; Brain; Calcium; Cells; Cerebral cortex; Chimeric Proteins; Chromatin; Chronic; Clustered Regularly Interspaced Short Palindromic Repeats; Data; Dependovirus; Development; Disease; Distal; Distal Enhancer Elements; Enhancers; Environment; Epigenetic Process; Equilibrium; Foundations; Future; Gatekeeping; Gene Expression; Gene Expression Profile; Gene Expression Regulation; Genes; Genetic; Genetic Enhancer Element; Genetic Transcription; Genetic study; Glutamate Receptor; Guide RNA; Health; Image; Immunofluorescence Immunologic; Impairment; Knock-out; Learning; Light; Link; Long-Term Depression; Measures; Mediating; Methods; Molecular; Monitor; Mouse Strains; Mus; Neuronal Plasticity; Neurons; Physiological; Play; Population; Process; Property; Proteins; Publishing; Regulation; Regulator Genes; Regulatory Element; Reporter; Role; Sensory; Shapes; Slice; Specificity; Structure; Synapses; Synaptic plasticity; Testing; Time; Transcriptional Regulation; Transgenic Mice; Translations; Trauma; V1 neuron; Validation; Visual; Visual Cortex; Visual system structure; area striata; base; epigenetic regulation; epigenome editing; experience; experimental study; flexibility; histone acetyltransferase; imaging modality; in vivo; in vivo calcium imaging; knock-down; novel; orientation selectivity; overexpression; promoter; protein expression; protein function; receptive field; recruit; response; tool; two-photon; visual plasticity; visual stimulus

Project Summary The synaptic wiring diagram of the cerebral cortex is established during development, and the stability of this network in the adult brain is important for the ability of the cortex to reliably encode information about the sensory world. However, plasticity is also a fundamental feature of the mammalian brain, and a growing body of evidence is revealing that even core features of neuronal response properties, such as the orientation tuning of neurons in the visual cortex, are more dynamically plastic in the adult brain than previously thought. These data raise the question, how is the balance between the stability and the plasticity of synaptic connections maintained in the adult brain? Neuronal activity-dependent transcription and translation play essential roles in the organization of cortical networks during development, and these processes contribute to long-lasting plasticity of neuronal structure and function in the adult brain. Arc is among the most important of the activity regulated genes during cortical development, because Arc protein functions directly at synapses to endocytose AMPA-type glutamate receptors, inducing long-term depression (LTD) and input-specific synaptic elimination. Genetic knockout of Arc in adult primary visual cortex impairs receptive field plasticity, whereas overexpression of Arc enhances this plasticity. These data raise the interesting possibility that the molecular mechanisms of activity-dependent Arc expression may act to set the balance between flexibility and stability of cortical representations. However, no prior study has had the experimental means to selectively manipulate the activity-dependent regulation of genes like Arc in the adult brain in order to determine the consequences for cortical plasticity. The activity-dependent transcription of Arc is mediated by the interaction of the Arc promoter with a distal enhancer element located ~7kB upstream of Arc. We have shown that the CRISPR-based recruitment of dCas9-chromatin regulator fusion proteins to activity-dependent gene regulatory elements can be used to selectively modulate the activity-dependent component of gene expression. Here in Aim 1 we will use two novel strains of dCas9/CRISPR mice we have characterized to titrate the activity-dependent transcription of Arc and determine the consequences for the light-dependent regulation of Arc protein expression in the primary visual cortex (V1) in vivo. In Aim 2 we will use chronic in vivo calcium imaging methods to assess the consequences of impairing Arc induction on the stability and plasticity of orientation tuning in V1. Revealing such a relationship between epigenetic regulation of activity-dependent transcription and synaptic plasticity in the adult visual cortex has the potential to transform how neuroscientists approach the study of cortical function in health and disease.

项目摘要 在开发过程中建立了大脑皮层的突触接线图，并且稳定性 成人大脑中的网络对于皮质可靠编码有关的信息很重要 感官世界。但是，可塑性也是哺乳动物大脑的基本特征，并且身体不断增长 证据表明，即使是神经元反应特性的核心特征，例如方向调整 视觉皮质中的神经元的塑性比以前想象的要动态性更大。这些 数据提出了问题，突触连接的稳定性和可塑性之间的平衡如何 维持在成人大脑中？神经元活动依赖性转录和翻译在 开发过程中皮质网络的组织，这些过程有助于持久 成人大脑中神经元结构和功能的可塑性。 ARC是最重要的活动之一 在皮质发育过程中调节基因，因为电弧蛋白在突触中直接在内吞作用 AMPA型谷氨酸受体，诱导长期抑郁（LTD）和投入特异性突触消除。 成人初级视觉皮层中弧的遗传敲除损害接受场的可塑性，而过表达 ARC的可增强这种可塑性。这些数据提出了一种有趣的可能性，即分子机制 活动依赖性的弧表达可能会在皮质的柔韧性和稳定性之间设置平衡 表示。但是，没有先前的研究具有选择性操纵的实验手段 活性依赖于成人大脑中弧等基因的调节，以确定对 皮质可塑性。 ARC的活性依赖性转录是由弧启动子的相互作用介导的 远端增强子元件位于弧线上游〜7kb。我们已经证明了基于CRISPR的 DCAS9-染色质调节蛋白融合蛋白募集到活动依赖性基因调节元件可以 用于选择性调节基因表达的活性依赖性成分。在AIM 1中，我们将 使用两种新型DCAS9/CRISPR小鼠的菌株，我们已经表征了滴定活动依赖性的 ARC的转录并确定对电弧蛋白的光依赖性调节的后果 在体内的主要视觉皮层（V1）中的表达。在AIM 2中，我们将使用慢性体内钙成像 评估损害弧诱导对方向稳定性和可塑性的后果的方法 在V1中调整。揭示了活性依赖性转录的表观遗传调节之间的这种关系 成人视觉皮层中的突触可塑性有可能改变神经科学家的接近 健康和疾病中皮质功能的研究。