Dynamin-related protein 1 and mitochondrial fission adapters regulate presynaptic function

动力相关蛋白 1 和线粒体裂变接头调节突触前功能

基本信息

批准号：
10660812
负责人：
ROBERT B RENDEN
金额：
$ 45.02万
依托单位：
UNIVERSITY OF NEVADA RENO
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-09-18 至 2028-08-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10660812
关键词：
Acute Adaptor Signaling Protein Adjuvant Affect Aging Alzheimer&apos s Disease Basic Science Biogenesis Biological Models Brain Cell Survival Cell membrane Cell physiology Cells Cellular Stress Chronic Collaborations Data Defect Development Disease Disease Progression Dissection Dynamin Dynamin III Electric Capacitance Electron Microscopy Electrophysiology (science)Embryo Endocytosis Environment Excision Excitatory Synapse Fluorescence Functional disorder Gene Transfer Techniques Glutamates Goals Health Homeostasis Human Huntington Disease Impairment Intervention Investigation Knowledge Measurement Mediating Membrane Mitochondria Modeling Morphology Motivation Mus Nerve Degeneration Nervous System Neurodegenerative Disorders Neurons Organism Outer Mitochondrial Membrane Phenotype Plasma Play Population Preparation Presynaptic Terminals Process Protein Isoforms Proteins Reactive Oxygen Species Recycling Regulation Research Research Personnel Resolution Respiration Retrieval Role Route Shapes Site Slice Stress Synapses Synaptic Transmission Synaptic Vesicles Testing Therapeutic Time Tissues Viral Work age related electron tomography functional restoration healthspan light microscopy loss of function mitochondrial dysfunction nanoscale nervous system disorder neurotransmission novel strategies postnatal presynaptic presynaptic neurons reconstruction recruit response stressor synaptic function therapeutic target

项目摘要

The long-term goal of this project is to ameliorate neurotransmission defects due to mitochondrial dysfunction, as a way to stop disease progression to later degenerative stages, increasing healthspan in populations increasingly subject to age-related neurological diseases. Dynamin-related protein 1 (DRP1) acts to promote mitochondrial fission and has been identified as a therapeutic target for limiting aberrant mitochondrial fragmentation in Alzheimer’s and Huntington’s disease. The goal of this project is to determine how DRP1 interaction with mitochondrial fission adapters impacts presynaptic terminal function. We propose that the need for high levels of mitochondrial respiration to support synaptic transmission makes the presynaptic terminal a high cellular stress environment. Regulated mitochondrial fission is important for cell survival in response to cellular stressors, acting through DRP1, but the adapters utilized at the neuronal presynaptic terminal are unknown. In Specific Aim 1, we will examine how loss of the mitochondrial fission adapter proteins MFF and FIS1 affect mitochondria homeostasis and synaptic transmission. In Specific Aim 2, we will examine distinct parameters of mitochondrial function and ultrastructure when DRP1 is eliminated, and attempt to rescue function by targeting DRP1 re-expression to mitochondrial outer membrane. Phenotypic differences will be corelated with those in Aim 1, to generate a complete picture of the effect of regulated mitochondrial fission on synaptic function. DRP1 may also facilitate scission of plasma membrane at the synapse, but the impact of this additional function on synaptic transmission is unresolved. In Specific Aim 3, we will test the hypothesis that DRP1 facilitates synaptic vesicle retrieval and recycling, and determine whether membrane-associated DRP1 is sufficient to facilitate SV retrieval, and restore synaptic transmission. In collaboration, the PI and two other world-class investigators have developed novel approaches to allow dissection of the isoform-specific role(s) of DRP1, using the mouse calyx of Held as a model system. Using a combination of viral-mediated transgenesis, advanced electrophysiology, and high-resolution light and electron microscopy, the ability of specific DRP1 isoforms to support mitochondrial fission versus synaptic transmission and presynaptic SV retrieval will be systematically tested. In contrast to small conventional synapses, experimental accessibility of giant ‘calyx-like’ excitatory synapses allow recordings from the presynaptic terminal, permitting manipulation of presynaptic [ATP] and tracking membrane exo/endocytosis in real time. This approach is necessary to dissect the energy-supporting roles of synaptic mitochondria from mechanisms underlying synaptic vesicle recycling. Results from this project can be used to inform, predict, and test function and dysfunction at conventional glutamatergic synapses where disease-relevant neurodegeneration first appears. Knowledge generated from this project will identify viable routes of intervention for restoring function to synapses where DRP1 function is altered, which can be leveraged therapeutically to alleviate disease-related synaptic dysfunction and neurodegeneration.

该项目的长期目标是改善因线粒体功能障碍而导致的神经传递缺陷，作为阻止疾病发展到后来退化阶段的一种方式，增加了人群的健康状况越来越多地受到与年龄相关的神经系统疾病的影响。动力蛋白相关的蛋白1（DRP1）起作用线粒体裂变，已被确定为限制异常线粒体的治疗靶点阿尔茨海默氏病和亨廷顿氏病的分裂。该项目的目的是确定DRP1的方式与线粒体裂变适配器的相互作用会影响突触前终末功能。我们建议需要为了高水平的线粒体呼吸以支持突触传播高细胞应力环境。受调节的线粒体裂变对于响应细胞存活很重要通过DRP1作用的细胞应激源，但是在神经元前末端使用的适配器是未知。在特定目标1中，我们将研究线粒体裂变适配器蛋白MFF和 FIS1影响线粒体稳态和突触传播。在特定的目标2中，我们将研究独特的消除DRP1时线粒体功能和超微结构的参数，并尝试挽救功能通过将DRP1重新表达到线粒体外膜。表型差异将与在AIM 1中的那些，以产生调节线粒体裂变对突触功能的影响的完整图。 DRP1也可能促进突触时质膜科学，但这种附加功能的影响关于合成传输尚未解决。在特定目标3中，我们将测试DRP1收藏夹的假设突触囊泡检测和回收利用，并确定与膜相关的DRP1是否足以促进SV检索，并恢复突触传播。在合作中，PI和其他两个世界一流研究人员开发了新的方法，以允许使用DRP1的同工型特异性作用。作为模型系统持有的鼠标花萼。结合病毒介导的转基因，先进电生理学以及高分辨率的光和电子显微镜，特定的DRP1同工型至支持线粒体裂变与突触传播，并系统地检索突触前SV。测试。与小型常规突触相反，巨型“花萼状”兴奋性的实验可及性突触允许从突触前末端进行记录，允许操纵突触前[ATP]和实时跟踪膜外移/内吞作用。这种方法对于剖析能量支持是必要的合成囊泡回收的机制中合成线粒体的作用。该项目的结果可用于在传统的谷氨酸能突触上为此提供，预测和测试功能以及功能障碍首次出现与疾病相关的神经变性。该项目产生的知识将确定可行恢复功能到更改DRP1功能的突触的干预途径，可以利用它治疗以减轻与疾病相关的突触功能障碍和神经退行性的。