Using Drosophila to investigate the development and function of nervous systems.

使用果蝇研究神经系统的发育和功能。

• 批准号: RGPIN-2017-05142
• 负责人: VanMeyel, Donald
• 金额: $ 2.91万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=688158
• 关键词: Using; Drosophila; investigate; development; function

Monoamines are class of neuromodulators that are crucial for a variety of brain functions, including control of mood, movement, cognition, and sleep. Like mammals, the Drosophila nervous system is enriched in monoamines, mainly dopamine, serotonin and octopamine. Distinct populations of monoaminergic neurons release these modulators within anatomically overlapping regions, allowing the brain to integrate environmental cues and regulate animal physiology. Re-uptake of these monoamines then occurs via specific transport proteins to prevent increased extracellular concentration at synapses. During normal cellular metabolism, monoamines are acetylated by the enzyme dopamine N-acetyl transferase (Dat), a Drosophila member of the conserved family of aaNAT (alkylarylamine N-acetyltransferase) proteins. Interestingly, N-acetyl serotonin is a precursor in the synthesis of melatonin, a hormone that induces sleep. We have made a new antibody to Dat and found it to be expressed in some but not all classes of monoaminergic neurons, and likely in neurons expressing other neurotransmitters such as GABA and glutamate. Strikingly, we also found Dat to be expressed in astrocytes, where it is enriched in the fine membranous processes that infiltrate CNS neuropil. The physiological role of astrocytes in monoamine processing is not well understood. We hypothesize that Drosophila astrocytes take up monoamines from synapses and process them via Dat to affect neuromodulation of specific behaviors. In preliminary experiments we find that Dat produced in astrocytes is required for flies to achieve correct levels and timing of sleep. In this grant application, we propose to use genetic approaches to investigate Dat function in Drosophila astrocytes, and to explore with immunohistochemistry, biochemistry and behavioral assays how Dat function might provide selective activity depending on the cell type in which it is expressed. In Aim 1 we will characterize the spatial and temporal patterns of Dat expression in the adult fly brain. In Aim 2 we will measure the biochemical effects of Dat activity in astrocytes and specific neuronal subtypes. In Aim 3 we will determine how Dat influences sleep in Drosophila.******This grant will create new understanding of cellular and molecular mechanisms that control the bioavailability and function of monoamines in the CNS. Moreover, it will provide excellent conceptual and technical training for undergraduate and graduate students interested in understanding fundamental aspects of brain function.

单胺类神经调节剂对大脑的各种功能至关重要，包括控制情绪、运动、认知和睡眠。像哺乳动物一样，果蝇的神经系统富含单胺，主要是多巴胺、5-羟色胺和章鱼胺。不同群体的单胺能神经元在解剖重叠的区域内释放这些调节剂，使大脑能够整合环境线索并调节动物生理。然后通过特定的运输蛋白重新摄取这些单胺，以防止突触细胞外浓度增加。在正常的细胞代谢中，单胺被多巴胺N-乙酰转移酶(DAT)乙酰化，DAT是果蝇AANAT(烷基芳胺N-乙酰转移酶)保守家族的成员。有趣的是，N-乙酰-5-羟色胺是褪黑素合成的前体，褪黑素是一种诱导睡眠的激素。我们已经制作了一种新的抗Dat的抗体，并发现它在一些但不是所有类型的单胺能神经元中都有表达，而且可能在表达其他神经递质的神经元中表达，如GABA和谷氨酸。值得注意的是，我们还发现Dat在星形胶质细胞中表达，它在渗透到CNS神经纤维的细膜突起中丰富。星形胶质细胞在单胺加工中的生理作用还不是很清楚。我们假设果蝇星形胶质细胞从突触中摄取单胺，并通过DAT处理它们来影响特定行为的神经调节。在初步实验中，我们发现在星形胶质细胞中产生的DAT是果蝇达到正确的睡眠水平和时间所必需的。在这项拨款申请中，我们建议使用遗传学方法来研究Dat在果蝇星形胶质细胞中的功能，并通过免疫组织化学、生物化学和行为分析来探索Dat功能如何根据其表达的细胞类型提供选择性活性。在目标1中，我们将描述成虫大脑中DAT表达的空间和时间模式。在目标2中，我们将测量DAT活性对星形胶质细胞和特定神经元亚型的生化影响。在目标3中，我们将确定DAT如何影响果蝇的睡眠。*这项拨款将对控制中枢神经系统中单胺类物质的生物利用度和功能的细胞和分子机制产生新的理解。此外，它还将为对了解大脑功能基本方面感兴趣的本科生和研究生提供出色的概念和技术培训。