Neurotrophin-Induced Regulation of the microRNA Processing Factor Lin28a

神经营养素诱导的 microRNA 加工因子 Lin28a 的调节

• 批准号: 8714244
• 负责人: ALEXANDRA M AMEN
• 金额: $ 4.27万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-01 至 2017-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8714244
• 关键词: Anxiety; Anxiety Disorders; Autistic Disorder; Behavioral; Binding; Biochemical Genetics; Biogenesis; Biological Models; Brain; Brain Diseases; Brain-Derived Neurotrophic Factor; Cell physiology; Cells; Chronic; Cognition Disorders; Complex; Disease; Family; Future; Gene Expression; Gene Expression Regulation; Genetic Transcription; Goals; Growth; Growth and Development function; Hippocampus (Brain); Human; Image Analysis; Immunohistochemistry; In Vitro; Knowledge; Laboratories; Learning; Light; Malignant Neoplasms; Malignant neoplasm of brain; Mediating; Memory; Mental Depression; Mental disorders; Messenger RNA; Methods; MicroRNAs; Modeling; Molecular; Mood Disorders; Mus; Nerve Degeneration; Neuraxis; Neurodegenerative Disorders; Neurons; Neurophysiology - biologic function; Oncogenic; Outcome; Pathway interactions; Phosphorylation; Physiological; Plastics; Play; Post-Traumatic Stress Disorders; Process; Production; Protein Biosynthesis; Proteins; Proteome; RNA; RNA-Binding Proteins; Regulation; Repression; Research; Role; Schizophrenia; Signal Pathway; Signal Transduction; Specificity; Stimulus; Structure; Synapses; Synaptic plasticity; System; Techniques; Testing; Therapeutic; Therapeutic Agents; Training; Translations; Ubiquitin; Work; base; cancer cell; cell type; cellular imaging; cognitive function; functional outcomes; human DICER1 protein; in vivo; inhibitor/antagonist; nerve stem cell; nervous system disorder; neuron loss; neuronal growth; neuronal survival; neurotrophic factor; new therapeutic target; novel; overexpression; pluripotency; prevent; programs; public health relevance; research study; response; synaptic function; therapeutic target; tumorigenesis

DESCRIPTION (provided by applicant): Synaptic plasticity, regarded as the cellular correlate of learning and memory, involves a selective strengthening and weakening of synapses in response to neuronal activity. Changes in gene expression combined with novel protein synthesis have long been recognized as necessary for lasting changes in synaptic connections. However, surprising recent studies have shown that regulation at the level of transcription is not necessarily correlated with regulation at the level of translation, and thus that the profile of mRNA in a cell is only moderately correlated with the proteome. Brain-derived neurotrophic factor (BDNF) is a crucial regulator of long-lasting changes in synaptic connectivity. It plays an important role in consolidation of learning and memory, and is misregulated in a wide range of neurologic and cognitive disorders including mood disorders, anxiety disorders, and Schizophrenia as well as neurodegenerative disease. Interestingly, BDNF enhances the expression of an extraordinarily specific subset (about 4%) of transcribed mRNAs by regulating components of the microRNA biogenesis pathway. One important aspect of this regulation is the induction of a protein called Lin28a, which is a pluripotency factor that inhibits biogenesis of specific microRNAs and was thought previously to be absent from mature cell types such as neurons. The first goal of the proposed research is to understand the molecular mechanisms and signaling pathways through which BDNF enhances Lin28a protein, thus regulating gene expression. Understanding such mechanisms involved in the BDNF signaling pathway has the potential to uncover regulatory points that could be the target of future therapeutics. Experiments in this section will require molecular, biochemical, and genetic approaches to analyze BDNF signaling outcomes in cultured mouse hippocampal neurons. Additionally, the second goal of the proposed research is to enhance and repress activity of Lin28a protein in in vitro and in vivo neuronal systems. Analysis of cell morphological and behavioral readouts following these manipulations will directly indicate how BDNF-mediated induction of Lin28a protein may impact neuronal structure as well as cognitive function. These experiments have the potential to directly suggest therapeutic agents for cognitive and neurologic disorders. Methods in this section will include immunohistochemistry, fixed cell imaging and analysis, and assessment of hippocampal-based learning tasks in wild type and genetically manipulated mice. Overall, the proposed experiments will enhance our current knowledge of the molecular mechanisms that underlie learning and memory normally and that may be dysregulated in diseases and disorders of the brain.

描述（由申请人提供）：突触可塑性被认为是学习和记忆的细胞相关性，涉及响应神经元活动而选择性地加强和削弱突触。基因表达的变化与新型蛋白质合成相结合长期以来一直被认为是突触连接持久变化所必需的。然而，令人惊讶的最近研究表明，转录水平的调节不一定与翻译水平的调节相关，因此细胞中mRNA的谱与蛋白质组仅中度相关。脑源性神经营养因子（BDNF）是突触连接长期变化的重要调节因子。它在巩固学习和记忆方面发挥着重要作用，并且在多种神经系统和认知障碍中受到失调，包括情绪障碍、焦虑症、精神分裂症以及神经退行性疾病。有趣的是，BDNF 通过调节 microRNA 生物发生途径的组成部分来增强转录 mRNA 的极其特定的子集（约 4%）的表达。这种调节的一个重要方面是诱导一种名为 Lin28a 的蛋白质，它是一种抑制特定 microRNA 生物发生的多能因子，之前被认为在神经元等成熟细胞类型中不存在。该研究的首要目标是了解 BDNF 增强 Lin28a 蛋白从而调节基因表达的分子机制和信号通路。了解 BDNF 信号通路中涉及的此类机制有可能发现可能成为未来治疗目标的调节点。本节中的实验将需要分子、生化和遗传学方法来分析培养的小鼠海马神经元中的 BDNF 信号转导结果。此外，该研究的第二个目标是增强和抑制 Lin28a 蛋白在体外和体内神经元系统中的活性。这些操作后对细胞形态和行为读数的分析将直接表明 BDNF 介导的 Lin28a 蛋白诱导如何影响神经元结构和认知功能。这些实验有可能直接建议治疗认知和神经系统疾病的药物。本节中的方法将包括免疫组织化学、固定细胞成像和分析，以及对野生型和基因操纵小鼠中基于海马的学习任务的评估。总体而言，所提出的实验将增强我们目前对正常学习和记忆基础的分子机制的了解，以及在大脑疾病和紊乱中可能失调的分子机制。