Cellular Neurobiology of the Retina

视网膜细胞神经生物学

• 批准号: 8435156
• 负责人: GARY G MATTHEWS
• 金额: $ 52.46万
• 依托单位: STATE UNIVERSITY NEW YORK STONY BROOK
• 依托单位国家: 美国
• 财政年份: 1981
• 资助国家: 美国
• 起止时间: 1981-08-01 至 2015-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8435156
• 关键词: Afferent Neurons; Auditory; Biological Assay; Biological Models; Bipolar Neuron; Cell membrane; Cells; Cellular Neurobiology; Complex; Cryopreservation; Distal; Docking; Dyes; Ear; Electron Microscopy; Electrophysiology (science); Ensure; Exocytosis; Eye; Goals; Hair Cells; Hearing; Image; Kinetics; Knowledge; Label; Labyrinth; Life; Light; Molecular; Molecular Analysis; Monitor; Motion; Mus; Names; Neuraxis; Neurons; Optics; Organelles; Output; Photoreceptors; Physiological; Process; Proteins; Recycling; Reporter; Resolution; Retina; Role; Sensory; Shapes; Signal Transduction; Site; Structure; Surface; Synapses; Synaptic Transmission; Synaptic Vesicles; System; Testing; Travel; Variant; Vesicle; Vision; Visual; Visual Perception; Wit; Work; Zebrafish; base; computerized data processing; cytomatrix; fluorescence imaging; ganglion cell; neuromechanism; neurotransmission; neurotransmitter release; presynaptic; protein expression; public health relevance; rab3A GTP-Binding Protein; red fluorescent protein; ribbon synapse; scaffold; single molecule; synaptic function; trafficking; transmission process; uptake; visual information; visual process; visual processing; voltage clamp

DESCRIPTION (provided by applicant): Ribbon synapses transmit sensory information in the visual, auditory, and vestibular systems and are essential for the function of these fundamental senses. These specialized synapses derive their name from a complex organelle, the synaptic ribbon, which is embedded in the cytomatrix at the presynaptic active zone of sensory neurons. When ribbons are disrupted, vision and hearing are strongly impaired, because ribbons are required for faithful transmission of sensory signals in the retina and inner ear. To carry out thi task, ribbons must support both fast, transient and slower, sustained release of neurotransmitter, which they accomplish by enhancing the size and accessibility of the readily releasable pool of synaptic vesicles. Ribbons tether large numbers of synaptic vesicles to their surface, and these vesicles are thought to constitute the readily releasable pool. However, the mechanism by which vesicles associated with ribbons contribute to release is still a mystery, in part because it has been difficult to monitor the activity of ribbons in living cells. One idea is hat the ribbon serves as a scaffold along which vesicles travel to the plasma membrane at the active zone, where they then dock and fuse. Another possibility is that ribbons facilitate compound exocytosis, by providing a means for vesicles to dock and fuse with each other. One major goal of this proposal is to test these two alternative views of ribbon function, using high-resolution imaging of fluorescently labeled ribbons and synaptic vesicles in living cells. If labeld vesicles move along ribbons, that motion should be directly observable. The project will employ several approaches for visualizing vesicles, including activity-dependent uptake of FM dyes, single-molecule tracking of vesicle proteins fused to photoactivatable variants of red fluorescent protein, and electron microscopy. In addition, vesicles labeled with a fluorescent reporter of exocytosis will allow localization of the site of vesicle fusion, to determine if vesicles fuse wit each other distal to the plasma membrane, or exclusively at the plasma membrane itself. Another major goal of the project is to determine the functional roles of proteins and physiological systems that dictate the dynamics of vesicle trafficking at the active zone, in order to arrive at a comprehensive understanding of the molecular mechanisms controlling neurotransmission at ribbon synapses. The results of the project will significantly advance fundamental knowledge about the early steps in transmission of sensory information in both vision and hearing.

描述（由申请人提供）：带状突触在视觉、听觉和前庭系统中传递感觉信息，并且对于这些基本感觉的功能至关重要。这些特殊的突触得名于一种复杂的细胞器，即突触带，它嵌入感觉神经元突触前活动区的细胞基质中。当丝带被破坏时，视力和听力会受到严重损害，因为丝带是视网膜和内耳中感官信号忠实传输所必需的。为了完成这项任务，丝带必须支持神经递质的快速、短暂和缓慢、持续的释放，它们通过增强易于释放的突触囊泡库的大小和可及性来实现这一点。带状结构将大量突触小泡束缚在其表面，这些小泡被认为构成了易于释放的池。然而，与丝带相关的囊泡促进释放的机制仍然是个谜，部分原因是很难监测活细胞中丝带的活性。一种想法是，丝带充当支架，囊泡沿着支架移动到活性区的质膜，然后在那里停靠并融合。另一种可能性是，丝带通过提供囊泡相互对接和融合的方式来促进复合胞吐作用。该提案的一个主要目标是使用活细胞中荧光标记带和突触小泡的高分辨率成像来测试带功能的这两种替代视图。如果标记的囊泡沿着丝带移动，则应该可以直接观察到该运动。该项目将采用多种方法来可视化囊泡，包括 FM 染料的活性依赖性摄取、与红色荧光蛋白的光激活变体融合的囊泡蛋白的单分子追踪，以及电子显微镜。此外，用胞吐作用荧光报告基因标记的囊泡将允许定位囊泡融合位点，以确定囊泡是否在质膜远端彼此融合，或仅在质膜本身融合。该项目的另一个主要目标是确定蛋白质和生理系统的功能作用，这些作用决定了活性区囊泡运输的动态，以便 全面了解控制带状突触神经传递的分子机制。该项目的结果将显着推进有关视觉和听觉感官信息传输早期步骤的基础知识。