Neurotransmitter Corelease

神经递质共释放剂

• 批准号: 9927697
• 负责人: ROBERT H EDWARDS
• 金额: $ 37.66万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-15 至 2022-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9927697
• 关键词: Anatomy; Behavior; Behavioral; Cells; Corpus striatum structure; Coupled; Couples; Dopamine; Future; GIRK2 subunit, G protein-coupled inwardly-rectifying potassium channel; GTP-Binding Protein alpha Subunits, Gs; GTP-Binding Proteins; Glutamate Receptor; Glutamate Transporter; Glutamates; Image; Measurement; Mental Depression; Midbrain structure; Molecular; Morphologic artifacts; Nervous system structure; Neurons; Neurotransmitters; Output; Physiological; Population; Property; Proteomics; Recycling; Role; Signal Transduction; Synaptic Vesicles; Vesicle; Work; dopaminergic neuron; in vivo; information processing; inward rectifier potassium channel; monoamine; pH gradient; postsynaptic; presynaptic; response; segregation; uptake; vesicular monoamine transporter

Accumulating evidence shows that many neurons release two classical neurotransmitters, but fundamental questions remain about the cellular basis for corelease, with important implications for its physiological role. In this proposal, we use the vesicular neurotransmitter transporters to elucidate the mechanisms involved in corelease. In previous work, we showed that glutamate corelease by midbrain dopamine neurons serves two distinct roles, one in vesicle filling with dopamine and the other as an independent signal. Although the effects on vesicle filling require colocalization of the vesicular monoamine transporter VMAT2 and vesicular glutamate transporter VGLUT2 on the same synaptic vesicles, anatomy has suggested some segregation as well, but with unclear physiological consequences. We now find that dopamine neurons release glutamate and dopamine with different properties. Release of the two transmitters differs in short-term depression and depends on different presynaptic Ca++ channels. Synaptic vesicles belong to pools that differ in response to stimulation but these differences have been attributed to extrinsic factors such as cytoskeletal association. We now show that they also differ in composition because they contain different transmitters and release them with different properties. Through this mechanism, a single neuron can deconvolve its input into two distinct outputs. The long-term objectives of this project are to elucidate the cellular and molecular basis for neurotransmitter corelease and determine its role in information processing. The strategy is to use the vesicular transporters to characterize the different vesicle populations. Specifically, we will 1) compare monoamine and glutamate release by imaging VMAT2 and VGLUT2 in live neurons; 2) determine how VMAT2 and VGLUT2 target to distinct vesicle populations; 3) characterize the composition of monoamine and glutamate SVs by proteomics. The results will provide basic information about the organization of neurons, with direct relevance for corelease by other cells, but also for release by all neurons.

越来越多的证据表明许多神经元释放两种经典的神经递质，但是 关于共释放的细胞基础仍然存在基本问题，这对其具有重要意义 生理作用。在这个提案中，我们使用囊泡神经递质转运蛋白来阐明 参与共释放的机制。在之前的工作中，我们证明了中脑共同释放谷氨酸 多巴胺神经元有两种不同的作用，一种是在囊泡中填充多巴胺，另一种是作为独立的神经元 信号。尽管对囊泡填充的影响需要囊泡单胺转运蛋白的共定位 解剖学表明，VMAT2 和囊泡谷氨酸转运蛋白 VGLUT2 位于同一突触囊泡上 也有一些分离，但生理后果尚不清楚。 我们现在发现多巴胺神经元释放具有不同特性的谷氨酸和多巴胺。发布 两种递质的短期抑制程度不同，并且取决于不同的突触前 Ca++ 通道。 突触小泡属于对刺激反应不同的池，但这些差异已归因于 外在因素，例如细胞骨架关联。我们现在表明它们在成分上也有所不同，因为 它们包含不同的发射器并释放具有不同特性的发射器。通过这种机制，单一 神经元可以将其输入反卷积为两个不同的输出。该项目的长期目标是阐明 神经递质共释放的细胞和分子基础并确定其在信息处理中的作用。 该策略是使用囊泡转运蛋白来表征不同的囊泡群体。具体来说， 我们将 1) 通过对活体神经元中的 VMAT2 和 VGLUT2 进行成像来比较单胺和谷氨酸的释放； 2) 确定 VMAT2 和 VGLUT2 如何靶向不同的囊泡群体； 3）通过蛋白质组学表征单胺和谷氨酸SV的组成。 结果将提供有关神经元组织的基本信息，与共释放直接相关 由其他细胞释放，也由所有神经元释放。