Role of Fat3 at the intersection of neuronal morphology and synapse localization

Fat3 在神经元形态和突触定位交叉点中的作用

• 批准号: 8644420
• 负责人: Steven J Henle
• 金额: $ 5.15万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-15 至 2016-05-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8644420
• 关键词: Amacrine Cells; Architecture; Axon; Biological; Biological Assay; Biological Models; Biomedical Research; Cadherins; Cell Communication; Cell Culture Techniques; Cells; Controlled Environment; Cues; Cytoskeleton; DNA Sequence Rearrangement; Data; Dendrites; Development; Developmental Process; Disease; Environment; Event; Excision; Failure; Genetic; Genetic Models; Golgi Apparatus; Image; In Situ; In Vitro; Injury; Inner Plexiform Layer; Knock-out; Label; Lead; Link; Location; Mammals; Mediating; Molecular; Monitor; Morphogenesis; Morphology; Mus; Mutant Strains Mice; Nervous system structure; Neurites; Neurodegenerative Disorders; Neurons; Neuropil; Neurosciences; Optic Nerve; Parvalbumins; Pattern; Phenotype; Play; Population; Positioning Attribute; Process; Protein Binding Domain; Proteins; Retina; Retinal; Retinal Ganglion Cells; Role; Shapes; Signal Transduction; Slice; Specific qualifier value; Synapses; System; Testing; Time; Tissues; Training; Work; axon guidance; extracellular; imaging modality; in vivo; insight; migration; mutant; novel; public health relevance; repaired; response; success; superior colliculus Corpora quadrigemina; synaptogenesis; therapeutic development; therapy development; time use; tool

DESCRIPTION (provided by applicant): Repairing the nervous system after injury, neurodegenerative disease, or dysfunctional development represents a significant challenge to biomedical research. Understanding how newly born neurons are guided by signals in their environment to form the correct neuronal morphology and synaptic connections is key to developing therapies to repair these disease states. Our current understanding of how neurons develop their specific shape and set of synapses is primarily the result of cell culture studies, where developing neurons are not exposed to the normal set of extracellular cues. This proposal combines mouse genetics, time-lapse imaging, and phenotypic analysis to understand how neuronal polarization and synaptogenesis are orchestrated in the context of the developing tissue. The atypical cadherin Fat3 offers a unique molecular entry point to investigate the relationship between synapse formation and neuronal morphology. Fat3 is expressed in the amacrine and retinal ganglion cells of the retina. Genetic deletion of fat3 in mice results in ectopic synapses and disrupted morphology in amacrine cells. The events that underlie this phenotype are unknown. This proposal will test the central hypothesis that Fat3 mediates cell-cell interactions that position and shape axons and dendrites, which in turn restricts synaptic location. To this end I will investigate the role of Fat3 in linking extracellular cues to neuronal polarity and synaptogenesis, and then ask if Fat3 plays a similar role in the development of other neurons. Specific Aim 1 is focused on investigating cellular events that lead to the correct development of amacrine cells, and then determining what events are Fat3-dependent. Establishment of a novel time-lapse retinal slice imaging method will facilitate the analysis of single amacrine cells developing in their natural context in mammals. Additionally, this aim seeks to understand the relationship between neuronal polarization and synaptogenesis. Specific Aim 2 is directed at understanding the role of Fat3-mediated cell-cell interactions with other neurons that controls the development of retinal ganglion cell axonal and dendritic morphology. Deletion of fat3 from specific populations of retinal ganglion and amacrine cells, followed by phenotypic analysis of the morphology of the resulting retinal ganglion cell axon and dendrites will provide a clear understanding of how cell-cell contacts mediate development. Collectively, the work described here will provide novel insight into amacrine and retinal ganglion cell development. Specifically, the results will answer key questions about the relationship between neuronal morphology and synapse formation in the context of the extracellular environment, as well as the role of cellular interactions in forming neuronal circuit.

描述(由申请人提供)：在受伤、神经退行性疾病或功能发育障碍后修复神经系统是生物医学研究的一个重大挑战。了解新生神经元是如何由环境中的信号引导形成正确的神经元形态和突触连接的，是开发修复这些疾病状态的治疗方法的关键。我们目前对神经元如何发展其特定形状和一组突触的理解主要是细胞培养研究的结果，在细胞培养研究中，发育中的神经元不会接触到正常的细胞外线索。这一建议结合了小鼠遗传学、时间推移成像和表型分析，以了解神经元极化和突触发生是如何在发育中的组织的背景下协调的。非典型钙粘附素Fat3为研究突触形成与神经元形态之间的关系提供了一个独特的分子切入点。Fat3在视网膜的无长突细胞和视网膜神经节细胞中表达。在小鼠中，FAT3基因缺失会导致异位突触，并破坏无长突细胞的形态。这种表型背后的事件尚不清楚。这一提议将检验中心假设，即Fat3介导细胞与细胞的相互作用，定位和塑造轴突和树突，进而限制突触的位置。为此，我将研究Fat3在连接细胞外信号和神经元中的作用 极性和突触发生，然后问Fat3在其他神经元的发育中是否起到类似的作用。具体目标1专注于研究导致无长突细胞正确发育的细胞事件，然后确定哪些事件是脂肪3依赖的。建立一种新的延时视网膜切片成像方法将有助于分析哺乳动物中单个无长突细胞在其自然环境中发育的情况。此外，这个目标试图了解神经元极化和突触发生之间的关系。具体目的2旨在了解Fat3介导的细胞与其他神经元之间的相互作用在控制视网膜神经节细胞、轴突和树突形态发育中的作用。从视网膜神经节和无长突细胞的特定群体中删除FAT3，然后对由此产生的视网膜神经节细胞轴突和树突的形态进行表型分析，将提供对细胞-细胞接触如何调节发育的清楚理解。总而言之，这里描述的工作将为无长突细胞和视网膜神经节细胞的发育提供新的见解。具体地说，这些结果将回答关于细胞外环境中神经元形态和突触形成之间的关系以及细胞相互作用在形成神经元回路中的作用等关键问题。