Regulation of Synapse Morphogenesis in Drosophila

果蝇突触形态发生的调控

基本信息

批准号：
9262285
负责人：
David L. Van Vactor
金额：
$ 37.08万
依托单位：
HARVARD MEDICAL SCHOOL
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-04-01 至 2019-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9262285
关键词：
Address Antibodies Architecture Bioinformatics Biological Biological Assay Biological Models Biology Brain region Cell Communication Cells Chemical Synapse Collection Complex Data Defect Dependence Detection Development Dissection Drosophila genus Electrophysiology (science)Embryo Employee Strikes Family Funding Gene Mutation Gene Targeting Genes Genetic Genetic Models Genetic Transcription Genetic Translation Glutamates Goals Grant Growth In Vitro Individual Informatics Knowledge Letters Logic Maintenance Maps Mediating Mental disorders Messenger RNA Methods MicroRNAs Microscopy Modeling Molecular Morphogenesis Motor Neurons Muscle Muscle Cells Nervous System Physiology Nervous system structure Neuromuscular Junction Neurons Orthologous Gene Pathway interactions Phenotype Phylogeny Porifera Positioning Attribute Process Proteins RNA Reagent Regulation Resolution Resources Shapes Side Signal Pathway Signal Transduction Source Specificity Structure Synapses Synaptic Transmission Synaptosomes System Technology Testing Transgenic Organisms Translations Transmission Electron Microscopy Untranslated RNA Work cell type experimental study gene function human disease improved in vivo mRNA Expression mRNA Stability morphometry multilevel analysis mutant nervous system disorder neural circuit novel overexpression postsynaptic presynaptic public health relevance relating to nervous system sensor spatiotemporal synaptic function synaptogenesis tool trafficking transcriptome

项目摘要

DESCRIPTION (provided by applicant): The formation and maturation of chemical synapses is essential to all major functions of the nervous system. Synaptogenesis represents a complex process of coordinated morphogenesis governed by highly conserved signaling pathways and intracellular effector proteins. Over the past decade, accumulated evidence revealed that this process is under regulatory control of various post-transcriptional mechanisms, from RNA trafficking to local translation, that offer the spatial acuity needed for the complex architectureof neurons and neural circuits. Amongst the sequence-specific regulators that may shape the translation and stability of key neuronal mRNAs, microRNAs (miRs) have recently emerged as a rich potential source. This large and diverse class of non-coding RNA is expressed abundantly in the nervous system, with hundreds of miRs localized to different brain regions, specific neuronal subpopulations and synaptic compartments. Despite impressive advances in the sequencing and informatics technologies required to detect miRs and their targets within the transcriptome, a comprehensive analysis of miR functions required for synaptogenesis was largely limited to in vitro systems where the endogenous cell-cell interaction and developmental signals are lost. In order to address this challenge, we spent the first cycle of funding on this grant developing genetic tools for conditional manipulation and detection of miR function in a model system that has proven to be a powerful model of excitatory glutamatergic synaptic transmission: the Drosophila neuromuscular junction (NMJ). We used our toolkit to dissect a novel trans-synaptic mechanism by which miR-8 regulates coordinated morphogenesis of pre- and post-synaptic compartments during development, in addition to experiments to prove the efficacy of these tools for a variety of experimental questions. We then created a collection of improved reagents to analyze synapse- regulatory function for 141 miRs, and completed a screen revealing that there are dozens of well-conserved miRs required for distinct aspects of NMJ formation. This pioneering effort has put us in a unique position to map out the spatio-temporal landscape of miR regulation for each of the stages of synapse formation and maturation in this system. We have identified two particular miRs that exert potent and reciprocal regulatory effects on opposite sides of the synapse: miR-34 is required in muscle to control addition and spacing of presynaptic boutons, whereas, miR-137 is required in neurons to restrict the overall growth of presynaptic arbors. Both miR-34 and miR-137 show striking conservation to genes implicated in neurological and psychiatric disease, confirming that they are functionally relevant across phylogeny, and suggesting that deeper analysis in our model can be used to ask if the downstream mechanisms are also conserved. In parallel with experiments to define the miRs that act in motor neurons and muscles to shape NMJ development, we will pursue a multi-level analysis of phenotypes and miR target gene networks in order to understand the cellular and molecular logic of the mechanisms by which conserved miRs control synaptogenesis.

描述（由申请人提供）：化学突触的形成和协调成熟对于神经系统的所有主要功能至关重要，突触发生代表了由过去十年积累的高度保守的信号通路和细胞内效应蛋白控制的复杂的形态发生过程。有证据表明，这一过程受到从 RNA 运输到局部翻译等各种转录后机制的调控，这些机制为神经元和神经回路的复杂结构提供了序列特异性所需的空间敏锐度。作为可能影响关键神经元 mRNA 翻译和稳定性的调节因子，microRNA (miR) 最近已成为一种丰富的潜在来源，这种大量且多样化的非编码 RNA 在神经系统中大量表达，数百种 miR 定位于神经系统。尽管在转录组中检测 miR 及其靶标所需的测序和信息学技术取得了令人瞩目的进展，但对突触发生所需的 miR 功能进行了全面分析。很大程度上局限于内源性细胞间相互作用和发育信号丢失的体外系统。为了应对这一挑战，我们在本次资助的第一轮资金中开发了用于条件操作和检测 miR 功能的遗传工具。模型系统已被证明是兴奋性谷氨酸突触传递的强大模型：果蝇神经肌肉接头（NMJ），我们使用我们的工具包剖析了 miR-8 调节协调的新型跨突触机制。除了通过实验证明这些工具对于各种实验问题的有效性之外，我们还创建了一系列改进的试剂来分析 141 个 miR 的突触调节功能，并完成了发育过程中突触前和突触后区室的形态发生。屏幕显示，NMJ 形成的不同方面需要数十种保存完好的 miR，这项开创性的工作使我们处于独特的地位，可以绘制每个 miR 调控的时空景观。我们已经确定了该系统中突触形成和成熟阶段的两个特定 miR，它们对突触的相对侧发挥有效和相互的调节作用：肌肉中需要 miR-34 来控制突触前纽扣的添加和间距，而，神经元需要 miR-137 来限制突触前乔木的整体生长，miR-34 和 miR-137 都对与神经和精神病相关的基因表现出惊人的保守性。疾病，证实它们在整个系统发育中具有功能相关性，并表明我们的模型中的更深入分析可用于询问下游机制是否也保守，同时进行实验来定义在运动神经元和肌肉中作用以塑造 NMJ 的 miR。在开发过程中，我们将对表型和 miR 靶基因网络进行多层次分析，以了解保守 miR 控制突触发生机制的细胞和分子逻辑。