Regulation of protein targeting in axon guidance and neuronal morphogenesis

轴突引导和神经元形态发生中蛋白质靶向的调节

• 批准号: 8809339
• 负责人: MARY C HALLORAN
• 金额: $ 36.82万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-15 至 2015-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8809339
• 关键词: Afferent Neurons; Alzheimer' s Disease; Axon; Axonal Transport; Behavior; Binding; Biosensor; Carrier Proteins; Cells; Charcot-Marie-Tooth Disease; Complex; Cues; Cytoskeleton; DNA Sequence Rearrangement; Defect; Development; Disease; Dynein ATPase; Early Endosome; Embryo; Endosomes; Environment; Event; F-Actin; Goals; Growth; Health; Human; Image; In Vitro; Individual; Injury; Kinesin; Label; Lead; Learning; Life; Ligands; Link; Location; Mediating; Mediator of activation protein; Membrane; Membrane Protein Traffic; Memory; Microtubules; Modeling; Molecular; Molecular Target; Morphogenesis; Morphology; Motor; Natural regeneration; Neurodegenerative Disorders; Neurons; Neurotrophic Tyrosine Kinase Receptor Type 3; Neurotrophin 3; Niemann-Pick Diseases; Pain Disorder; Pathway interactions; Peripheral; Process; Proteins; Regulation; Resolution; Role; Route; Semaphorin-3A; Semaphorins; Sensory; Signal Pathway; Signal Transduction; Structure; System; Testing; Time; Transport Vesicles; Zebrafish; axon growth; axon guidance; cell motility; extracellular; in vivo; in vivo Model; late endosome; mutant; neurite growth; neuronal transport; neurotrophic factor; novel; painful neuropathy; protein function; protein transport; receptor; relating to nervous system; research study; response; trafficking

DESCRIPTION (provided by applicant): Development of complex neuronal morphology and accurate neural connections requires tightly controlled axon outgrowth and responses to guidance signals in the cell environment. Precise subcellular localization of guidance cue receptors and localized signaling to the cytoskeleton are essential for axon guidance. Proteins are targeted to specific cell locations by complex membrane trafficking and axonal transport systems. Neurons are particularly dependent on diverse and high fidelity protein trafficking because of their highly polarized and complex structure. Defects in protein trafficking and transport underlie multiple human developmental and neurodegenerative diseases, including Alzheimer's disease, Charcot-Marie-Tooth, and Niemann Pick disease. Despite their importance, the mechanisms regulating these critical processes in neurons are poorly understood. A major challenge to the field and the long term goal of this project is to understand how protein localization and cytoskeletal dynamics are controlled as neurons develop in their natural environment, where they must integrate multiple extracellular cues. We established a model in which we can image dynamics of neuronal cargo transport, protein localization, and cytoskeletal changes in the intact zebrafish embryo. Vertebrate sensory neurons must extend distinct central and peripheral axons to form the sensory circuit. We found that these axons show distinct responses to axon guidance cues. Moreover, we discovered roles for endosomal trafficking and the kinesin adaptor Calsyntenin-1 (Clstn-1) in sensory axon guidance. In Aim 1 we propose to determine how Clstn-1 regulates endosome transport routes to different axon compartments. In Aim 2 we will investigate mechanisms regulating specific localization of receptors for Neurotrophin-3 and Semaphorin3d. We will test the hypothesis that Clstn-1 and another class of kinesin adaptors, the Collapsin response mediator proteins (CRMPs) function to target receptors to specific axon compartments. In Aim 3 we will determine how Clstn-1, CRMPs, Sema3d and Neurotrophin-3 converge to regulate localized cytoskeletal dynamics. Our unique model allows us to connect the molecular events of axonal transport, guidance receptor localization and cytoskeletal changes to specific axon guidance decisions at the time and place they naturally occur. Elucidation of the molecular signals regulating sensory axon growth, guidance, and protein trafficking is critical for understanding neurodegenerative disorders, neuropathic pain disorders and the conditions under which regeneration after axon injury can occur. Our experiments will uncover such mechanisms and thus may help to identify molecular targets for disease treatment.

描述（由申请人提供）：复杂神经元形态和精确神经连接的发育需要严格控制轴突生长和对细胞环境中指导信号的反应。精确的亚细胞定位的指导线索受体和本地化的信号传导到细胞骨架是必不可少的轴突的指导。蛋白质通过复杂的膜运输和轴突运输系统靶向特定的细胞位置。神经元由于其高度极化和复杂的结构，特别依赖于多样化和高保真的蛋白质运输。蛋白质运输和转运缺陷是多种人类发育和神经退行性疾病的基础，包括阿尔茨海默病、腓骨肌萎缩症和尼曼皮克病。尽管它们的重要性，调节神经元中这些关键过程的机制知之甚少。该领域的一个主要挑战和该项目的长期目标是了解蛋白质定位和细胞骨架动力学如何控制神经元在其自然环境中发育，在那里它们必须整合多种细胞外信号。我们建立了一个模型，在该模型中，我们可以在完整的斑马鱼胚胎中成像神经元货物运输，蛋白质定位和细胞骨架变化的动态。脊椎动物的感觉神经元必须延伸不同的中枢和外周轴突，以形成感觉回路。我们发现，这些轴突显示出不同的反应轴突的指导线索。此外，我们发现了内体运输和驱动蛋白适配器Calsyntenin-1（Clasmodin-1）在感觉轴突引导中的作用。在目标1中，我们提出确定Cloning-1如何调节内体转运途径到不同的轴突隔室。在目标2中，我们将研究调节神经营养素-3和脑信号蛋白3d受体特异性定位的机制。我们将测试的假设，Clapsin-1和另一类驱动蛋白衔接子，塌陷蛋白反应介体蛋白（CRMPs）的功能，以靶向受体的特定轴突隔室。在目标3中，我们将确定Climate-1，CRMPs，Sema 3d和神经营养因子-3如何收敛以调节局部细胞骨架动力学。我们独特的模型使我们能够将轴突运输，指导受体定位和细胞骨架变化的分子事件与它们自然发生的时间和地点的特定轴突指导决策联系起来。阐明调控感觉轴突生长、引导和蛋白质运输的分子信号对于理解神经退行性疾病、神经病理性疼痛疾病和轴突损伤后再生可能发生的条件至关重要。我们的实验将揭示这些机制，从而有助于确定疾病治疗的分子靶点。