Mechanisms of mRNA localization to neuronal synapses

mRNA 定位到神经元突触的机制

• 批准号: 8556203
• 负责人: Elliott James Meer
• 金额: $ 3.35万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-15 至 2014-09-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8556203
• 关键词: 3' Untranslated Regions; 5' Untranslated Regions; Afferent Neurons; Affinity Chromatography; Anxiety Disorders; Aplysia; Autistic Disorder; Base Sequence; Beryllium; Binding; Binding Proteins; Biological; Biological Models; Brain; Brain Diseases; Cells; Chemicals; Cognition Disorders; Development; Disease; Distal; Drug Addiction; Elements; Gene Expression; Genes; Genetic Transcription; Genetic Translation; Glutamates; Goals; Human Genetics; Image; Indium; Individual; Knowledge; Learning; Life; Mass Spectrum Analysis; Mediating; Memory; Memory Loss; Mental Retardation; Messenger RNA; Molecular; Motor Neurons; Mutagenesis; Mutation; Neurites; Neurons; Neuropeptides; Pharmacotherapy; Process; Protein Biosynthesis; Protein Dynamics; Proteins; RNA; RNA Stability; RNA-Binding Proteins; Reporter; Research; Role; Sensory; Serotonin; Structure; Synapses; Synaptic plasticity; System; Testing; Transcript; Translational Regulation; Translations; Untranslated Regions; Work; age related; aptamer; autism spectrum disorder; base; cell type; cellular imaging; cis acting element; experience; insight; mutant; neuropsychiatry; research study; stem; synaptic function; synaptogenesis; trafficking

DESCRIPTION (provided by applicant): The best biological correlate of learning and memory is synaptic plasticity, or changes in the number and strength of synapses with experience. Long-term synaptic plasticity is a transcription- and translation-dependent process that can be restricted to subsets of synapses within a single neuron. We propose that one mechanism for restricting gene expression to individual synapses is through mRNA localization and regulated translation. The model system Aplysia californica provides an excellent model system to study synaptic plasticity. Previous work in the Martin lab has demonstrated that protein synthesis can be spatially restricted to stimulated synapses during learning- related plasticity of cultured Aplysia sensory-motor neurons (Wang et al., 2009). In this proposal, I focus on the mechanisms underlying the synaptic localization of the mRNA encoding an Aplysia sensory cell-specific neuropeptide, sensorin. Studies in neurons and other asymmetric cell types have shown that localized transcripts often contain cis- acting localization elements in their untranslated regions (UTRs), which often are encoded by stem-loop structures. The Martin lab has demonstrated that the 5' and 3 untranslated regions (UTRs) of sensorin are sufficient for synaptic localization of reporter RNA. While the 3'UTR is required for distal neurite localization, the 5'UTR is required for synaptic localization. I have identified a 66 nucleotide sequence in the 5'UTR of sensorin mRNA that when paired with the sensorin 3'UTR is required and sufficient for sensorin mRNA synaptic localization. My experiments further indicate that this localization element is encoded by a stem-loop structure (Meer et al., 2012). Cis-acting RNA elements interact with trans-acting RNA binding proteins to mediate RNA localization. In addition to characterizing the neuritic RNA localization element in the sensorin 3'UTR, I propose experiments to determine how cis-acting elements function in the RNA stability and translation of sensorin. Finally, I will identify the RN binding proteins that localize sensorin mRNA to neurites and synapses and study the dynamics of these proteins during synapse formation. The results of the proposed experiments will provide insight into the cell and molecular biological mechanisms by which neurons are able to spatially restrict gene expression through mRNA localization and regulated translation. They are of significance to a range of brain disorders in which long-term synaptic plasticity is impaired, including autism, mental retardation, anxiety disorders and drug addiction.

描述（由申请人提供）：学习和记忆的最佳生物学相关性是突触可塑性，或者具有经验的突触的数量和强度变化。长期突触可塑性是转录和翻译依赖性过程，可以限于单个神经元内突触的子集。我们提出，将基因表达限制为个体突触的一种机制是通过mRNA定位和调节的翻译。 Model System Aplysia Californica为研究突触可塑性提供了出色的模型系统。马丁实验室中的先前工作表明，在培养的Aplysia感觉运动神经元的学习相关可塑性期间，蛋白质合成可以在空间上限制为刺激的突触（Wang等，2009）。在此提案中，我关注编码Aplysia感觉细胞特异性神经肽Sensorin的mRNA突触定位的机制。神经元和其他不对称细胞类型的研究表明，局部转录本通常包含在其未翻译区域中的定位元素 （UTRS），通常由茎环结构编码。马丁实验室已经证明，感觉素的5'和3个未翻译区域（UTR）足以足以进行报告基因RNA的突触定位。 While the 3'UTR is required for distal neurite localization, the 5'UTR is required for synaptic localization.我已经在5'UTR的5'UTR中鉴定了一个66个核苷酸序列，与Sensorin 3'Utr配对时，需要使用Sensorin mRNA突触定位。我的实验进一步表明，该定位元素是由茎环结构编码的（Meer等，2012）。顺式作用RNA元件与跨作用RNA结合蛋白相互作用以介导RNA定位。除了表征Sensorin 3'UTR中的神经RNA定位元件外，我还提出了实验，以确定顺式作用元件如何在RNA稳定性和Sensorin的翻译中起作用。最后，我将确定将感觉素mRNA定位于神经突和突触的RN结合蛋白，并研究突触形成过程中这些蛋白质的动力学。提出的实验的结果将提供有关细胞和分子生物学机制的见解，通过mRNA定位和调节的翻译，神经元能够通过空间限制基因表达。它们对长期突触可塑性受损的一系列脑部疾病具有重要意义，包括自闭症，智力低下，焦虑症和药物成瘾。