CAREER: Mitochondrial Transcellular Communication in the Nervous System: Mechanisms of Action and Student Training Opportunities

职业：神经系统中的线粒体跨细胞通讯：作用机制和学生培训机会

• 批准号: 2235079
• 负责人: Martha Bhattacharya
• 金额: $ 110万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2028-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2235079&HistoricalAwards=false
• 关键词: CAREER; Mitochondrial; Transcellular; Communication; Nervous

Most neurons in your brain are irreplaceable and must function in their circuits for life. To maintain the brain health, stressed or damaged neurons must receive support from surrounding cells to increase their chances of survival. To communicate with each other, both neurons and non-neuronal cells called glia release molecules that communicate their health status and elicit appropriate responses. Remarkably, one of the communication strategies that glia and neurons use involves the transfer of entire cellular organelles called mitochondria whose primary job is to produce energy. While the transfer of healthy, intact mitochondria improves neuronal function, the transfer of faulty mitochondria is toxic. How glia and neurons coordinate requests for and deliveries of mitochondria to ensure brain health is an unanswered question but one of vital importance. This project will elucidate the triggers for mitochondrial transfer, the cellular machinery used in their release, and the uptake mechanisms that integrate mitochondria into recipient cells. In doing so, the research will provide a window into a key process that could in the future be exploited to improve brain function throughout life. To perform aspects of this project, undergraduate students will participate in a unique credit-bearing, team-based research experience focused on neuron-glia communication and using the fruit fly as a model system. Undergraduate students will also participate in an outreach event to local elementary and middle school students. Taken together, the project will reveal new modes of cellular communication that underlie brain health and will provide training opportunities for the future scientific workforce.This project will establish the mechanisms and regulation of mitochondrial trans-cellular transfer (mitoTCT) in vivo by deploying an innovative combinatorial strategy of genetics, 3D microscopy, and imaging flow cytometry (iFACS) in the Drosophila nervous system. Using dual binary expression systems, neuronal and glial membranes and mitochondria will be labeled with four colors, facilitating unambiguous identification of the sources and directions of mitoTCT. In Aim 1, the project will elucidate key regulators of mitoTCT rate in vivo. This aim will test the hypothesis that nerve injury and/or excess neuronal activity can trigger mitoTCT from glia to neurons. In Aim 2, the project will determine the mechanism(s) by which mitochondria are transferred between glia and neurons. Three proposed modes of transfer (tunneling nanotubes, extracellular vesicles, and release of free mitochondria) will be evaluated by inhibition of each mechanism in a cell type specific manner. In both aims, the health status of mitochondria will be evaluated using genetically encoded redox sensors, which will determine whether the mode of action is leading to rescue or toxicity of recipient cells. This research will advance fundamental knowledge of neuron-glia communication via mitochondria and will illuminate how we might harness mitochondrial transfer for the benefit of neuronal health.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.

你大脑中的大多数神经元是不可替代的，必须在它们的电路中终生发挥作用。为了保持大脑健康，应激或受损的神经元必须得到周围细胞的支持，以增加它们的存活机会。为了相互交流，神经元和非神经元细胞都会释放分子，传达自己的健康状况，并引发适当的反应。值得注意的是，胶质细胞和神经元使用的通信策略之一涉及到整个细胞器(称为线粒体)的转移，线粒体的主要工作是产生能量。虽然健康、完整的线粒体的转移改善了神经元的功能，但有缺陷的线粒体的转移是有毒的。胶质细胞和神经元如何协调线粒体的请求和交付，以确保大脑健康是一个悬而未决的问题，但也是至关重要的问题之一。这个项目将阐明线粒体转移的触发因素，释放线粒体的细胞机制，以及将线粒体整合到受体细胞中的摄取机制。通过这样做，这项研究将提供一个窗口，让人们了解一个关键的过程，未来可以利用这个过程来改善一生中的大脑功能。为了完成这个项目的各个方面，本科生将参与一个独特的、有学分的、基于团队的研究体验，重点是神经元-神经胶质细胞的交流，并使用果蝇作为模型系统。本科生还将参加面向当地中小学生的外展活动。综上所述，该项目将揭示构成大脑健康基础的新的细胞通信模式，并将为未来的科学工作提供培训机会。该项目将通过在果蝇神经系统中部署遗传学、3D显微镜和成像流式细胞术(IFACS)的创新组合策略，建立体内线粒体跨细胞转移(MitoTCT)的机制和调节。使用双二元表达系统，神经细胞和神经胶质细胞膜以及线粒体将被标记为四种颜色，有助于明确识别mitoTCT的来源和方向。在目标1中，该项目将阐明体内有丝分裂细胞转移率的关键调控因素。这一目标将检验神经损伤和/或神经元过度活动可以触发从神经胶质细胞到神经元的有丝分裂转化的假说。在目标2中，该项目将确定线粒体在神经胶质细胞和神经元之间转移的机制(S)。三种拟议的转移模式(隧道纳米管、细胞外小泡和释放自由线粒体)将通过以特定细胞类型的方式抑制每种机制来进行评估。在这两个目标中，将使用遗传编码的氧化还原传感器来评估线粒体的健康状态，这将确定行动模式是否导致受体细胞的拯救或毒性。这项研究将促进通过线粒体进行神经元-神经胶质细胞通讯的基础知识，并将阐明我们如何利用线粒体转移来造福神经元健康。这一奖项反映了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。