Vesicular Acetylcholine Transporter Function in the Central Nervous System

调节神经递质乙酰胆碱(ACh)的合成、储存、释放和降解，对于正常的生物能力，如移动、思考和记忆能力是必不可少的。科学家目前了解大脑功能的这些方面所需的细胞和分子机制的主要元素，其中包括本项目关注的分子复合体，称为囊泡乙酰胆碱转运体(Vacht)。VAChT负责将乙酰胆碱运输到神经末梢内的突触小泡中，从而将其释放到靶细胞上。然而，VAChT介导这一运输过程的详细机制仍不清楚，Vacht相关的乙酰胆碱释放变化在调节行为变化中可能发挥的作用也不清楚。这个项目利用果蝇所拥有的优秀遗传资源来研究乙酰胆碱调节系统，以确定Vacht的变化如何影响乙酰胆碱的释放和上述行为的调节。该项目还利用各种复杂的工具和方法(包括记录飞行脑细胞的电活动的能力)来培训来自历史上代表性不足的少数族裔背景的本科生和研究生，使他们掌握一套最新的科学、技术、工程和数学(STEM)方面的可转移技能，并扩大少数族裔在高级STEM劳动力中的参与。该项目还包括通过虚拟实习计划对K-12学生进行研究、培训和教育。该项目的主要目标是通过收集果蝇中存在的一系列基因改变，确定囊泡乙酰胆碱转运体(Vacht)的具体变化如何改变乙酰胆碱(Ach)的释放。利用这种突变和过表达收集的各种实验将有助于阐明ACh释放和ACh连锁行为之间的关系。中心假说是，ACh突触释放的基础是一个倒V型模型，因此转运蛋白的强烈减少或过度表达会导致突触生理和ACh相关行为的严重缺陷，而Vacht表达的轻微增加将增强突触的活性。这项工作将使用三个具体目标来检验这一假设。目标1将确定Vacht的具体变化如何影响该蛋白质的表达、其活性和ACh水平。目的2通过检验Vacht表达的渐进性增加同时上调突触小泡释放和突触小泡融合的假说，来确定Vacht表达的变化如何影响突触小泡(SV)。目的3将确定血管功能的渐进性改变对ACh相关行为的影响。总而言之，该项目将促进我们对VACHT最终帮助调节突触释放的机制的理解。该项目由组织计划、既定的激励竞争研究计划(EPSCoR)和历史上的黑人学院和本科生计划(HBCU-UP)联合资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Regulation of the synthesis, storage, release and degradation of the neurotransmitter acetylcholine (ACh) is essential for normal organismal capabilities such as the ability to move, think and remember. Scientists presently understand the major elements of the cellular and molecular machinery required for these aspects of brain function, which include the molecular complex that this project is focused on, called the vesicular acetylcholine transporter (VAChT). VAChTs are responsible for transporting acetylcholine into synaptic vesicles inside nerve terminals so that it can be released onto its target cells. However, the detailed mechanisms through which VAChTs mediate this transport process remain unclear, as does the role that VAChT-related changes in acetylcholine release may play in regulating behavioral changes. This project uses the outstanding genetic resources that fruit flies possess for studying the acetylcholine regulation system to determine how changes in VAChT affect acetylcholine release and the regulation of the behaviors described above. This project also utilizes a wide range of sophisticated tools and methodologies (including the ability to record electrical activity from fly brain cells) to train undergraduate and graduate students from historically under-represented minority backgrounds, equipping them with an up-to-date set of transferrable skills in Science, Technology, Engineering and Math (STEM), and broadening the participation of minorities in the advanced STEM workforce. The project also includes a strong focus on research training and education of K-12 students through a virtual internship program.The main objective of this project is to determine how specific changes in the vesicular acetylcholine transporter (VAChT) alter acetylcholine (Ach) release by using a collection of genetic alterations available in Drosophila. A variety of experiments employing this mutation and overexpression collection will help elucidate the relationship between ACh release and ACh-linked behaviors. The central hypothesis is that an inverted V-shaped model underlies ACh synaptic release, such that strong decreases in or overexpression of the transporter cause severe defects in synaptic physiology and ACh-linked behavior, while mild increases in VAChT expression will enhance synaptic activity. The work will test this hypothesis using three Specific Aims. Aim 1 will determine how specific changes in VAChT affect that protein’s expression, its activity, and the levels of ACh. Aim 2 is focused on determining how changes in VAChT expression affect synaptic vesicles (SV) by testing the hypothesis that graded increases in VAChT upregulate both SV release and SV fusion. Aim 3 will determine the effects of graded changes in VAChT function on ACh-linked behaviors. Altogether, the project will advance our understanding of the mechanisms through which VAChT ultimately helps to mediate synaptic release.This project is jointly funded by the Organization Program, the Established Program to Stimulate Competitive Research (EPSCoR), and the Historically Black Colleges and Universities Undergraduate Program (HBCU-UP).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.