ULTRASTRUCTURAL BASIS FOR SYNAPTIC VESICLE RECYCLING IN CALYX OF HELD

持有花萼突触小泡回收的超微结构基础

• 批准号: 8169592
• 负责人: GEORGE A SPIROU
• 金额: $ 1.19万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-01 至 2011-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8169592
• 关键词: Area; Auditory; Brain Stem; Cell Nucleus; Cells; Characteristics; Communication; Complex; Computer Retrieval of Information on Scientific Projects Database; Elements; Filament; Funding; Goals; Grant; Growth Cones; Image; Institution; Laboratories; Link; Medial; Mitochondria; Mono-S; Mus; Nerve; Organelles; Postsynaptic Membrane; Recycling; Research; Research Personnel; Resolution; Resources; Shapes; Sound Localization; Source; Staging; Structure; Synapses; Synaptic Vesicles; Time; Transmission Electron Microscopy; United States National Institutes of Health; Work; base; digital; electron tomography; fluorescence imaging; metaplastic cell transformation; nerve supply; neuronal cell body; neurotransmission; postnatal; postsynaptic; presynaptic; reconstruction; research study; trapezoid body

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The calyx of Held and other large nerve terminals of the auditory brainstem are key elements of sound localization circuitry. Our goal is to reveal structural transformations and cellular communication that characterize contact of the calycigenic growth cone with its target and the early stages of synapse assembly and stabilization at large nerve terminals in the auditory brainstem. Our central hypothesis is that competition among calycigenic inputs precedes expansion of the terminal over the cell body to form a calyx. This hypothesis is based on work from our laboratory that reveals rapid formation of the calyx in mice between postnatal days (P)2 and P4. The calyx contains hundreds to greater than two thousand active zones, depending upon the species, many of which are located nearby specialized organelle complexes termed mitochondrion-associated adherens complexes (MACs). MAC structure had been described previously using standard transmission electron microscopy (sTEM), which revealed filaments tethering the mitochondrion to a punctum adherens that links the pre- and postsynaptic membranes. Confocal fluorescence imaging and electron tomography are being employed to study medial nucleus of the trapezoid body (MNTB) cell innervation during P0P4. This time period precedes and overlaps the formation of immature, cup-shaped calyces that envelop the MNTB cell body. These experiments will pinpoint time periods during which mono-innervation is established between pre- and postsynaptic partners and highlight structural and functional differences that may predict winning and losing inputs. In addition, we will describe structural features of mature calyces that support high-rate neurotransmission that is characteristic of this terminal. Because of the size of the calyx-MNTB contact and the desired high resolution of the reconstructions, serial volumetric imaging of domains of cells will be required. This project will require high-resolution, wide-field, large-area digital recording of images.

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 听觉脑干的Held萼和其他大的神经末梢是声音定位回路的关键元件。我们的目标是揭示结构转换和细胞通信的特点calycigenic生长锥与其目标和突触组装和稳定在听觉脑干中的大神经末梢的早期阶段的接触。我们的中心假设是，calycigenic输入之间的竞争之前，扩大终端的细胞体，形成一个萼。这一假设是基于我们实验室的工作，该工作揭示了小鼠在出生后（P）2和P4之间的肾盏快速形成。花萼包含数百到超过两千个活性区，取决于物种，其中许多位于称为细胞器相关粘附复合物（MACs）的专门细胞器复合物附近。MAC结构以前曾用标准的透射电子显微镜（sTEM）描述过，它揭示了将突触体拴在连接突触前膜和突触后膜的粘附点上的细丝。 应用共聚焦荧光成像和电子断层扫描技术研究P0时内侧核斜方体（MNTB）细胞的神经支配P4.这个时间段之前和重叠的未成熟的，杯状的花萼，包围MNTB细胞体的形成。这些实验将确定突触前和突触后伙伴之间建立单神经支配的时间段，并突出可能预测输赢输入的结构和功能差异。此外，我们将描述支持高速率的神经传递，这是终端的特点成熟的肾盏的结构特征。由于萼-MNTB接触的尺寸和重建的期望高分辨率，将需要细胞域的连续体积成像。该项目将需要高分辨率、宽视场、大面积的数字图像记录。