Feature characteristics and signaling mechanisms involved in SGN neurite guidance by engineered topographical and biochemical micropatterns

工程地形和生化微图案参与 SGN 神经突引导的特征特征和信号机制

• 批准号: 10667306
• 负责人: Joseph Thomas Vecchi
• 金额: $ 2.89万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-03-24 至 2023-11-05
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10667306
• 关键词: 3-Dimensional; Adult; Affect; Auditory; Behavior; Biochemical; Biochemical Pathway; Biological; Biological Process; Biomedical Engineering; Biophysics; Calcium Signaling; Career Choice; Characteristics; Cochlea; Cochlear Implants; Cochlear nucleus; Complex; Cues; Custom; Developmental Process; Dissociation; Electrodes; Engineering; Environment; Extracellular Matrix; Goals; Growth; Growth Cones; Guanosine Triphosphate Phosphohydrolases; Health; Human; Image; Implanted Electrodes; In Vitro; Individual; Inositol; Knowledge; Laboratories; Laminin; Learning; Machine Learning; Mediating; Methods; Modeling; Mus; Neonatal; Neurites; Neurobiology; Neurons; Organ of Corti; Outcome; Pathway interactions; Pattern; Peptides; Peripheral; Pharmacology; Polymers; Printing; Process; Research; Rho-associated kinase; Role; Signal Pathway; Signal Transduction; Sorting; Substrate Interaction; System; Techniques; Testing; Time; Translations; UV Radiation Exposure; Work; auditory stimulus; biophysical analysis; design; imaging approach; improved; inhibitor; inorganic phosphate; insight; interest; multidisciplinary; nerve supply; neural prosthesis; neurite growth; neuronal growth; novel; pharmacologic; photopolymerization; polymerization; real-time images; response; rho; skills; sound; spiral ganglion

Project Summary/Abstract The cochlea exploits an intricate tonotopic organization of afferent innervation to effectively process highly complex auditory stimuli. To create this precisely organized pattern, the neurites from spiral ganglion neurons (SGNs) navigate a complex milieu of cells, extracellular matrix, and biochemical gradients to reach their peripheral and central targets in the organ of Corti and cochlear nuclei, respectively. This process of a neurite growing through the environment is called pathfinding. In pathfinding, the tip of the neurite, the growth cone, senses, turns, and grows toward a target in response to biochemical and biophysical cues. This proposed research focuses on understanding how different substrate cues (topography, chemoattractive, and chemorepulsive) can promote an SGN neurite to turn as well as by which by signaling pathways a growth cone relies on to execute this basic biological process. Previous work has identified that engineered micropatterned substrates can be used to both (1) direct SGN growth and (2) study the signaling pathways activated by this phenomenon in vitro. We have demonstrated that neurons align their outgrowth to various engineered patterned substrates (topographical, chemoattractive, and chemorepulstive). Additionally, we have implicated RhoA-GTPase and calcium signaling in SGNs aligning their outgrowth to topographical cues. I propose to use this engineered micropatterned substrates to study (1) the hierarchy and interaction of topographical and biochemical cues in dictating neurite turning and (2) the biochemical pathways necessary for a growth cone to sense and turn in response to these cues. In particular, I will study how chemoattractive (laminin) and chemorepulsive (EphA4) interact with topographical growth cues when placed in complimentary (attractive in troughs) or antagonistic (repulsive in troughs) patterns. Additionally, I will research the role of Rho/ROCK and IP3 signaling in this basic biological process using pharmacology and imaging the activation of these pathways in real time when growing on various patterned substrates. Overall, the goal of this research is to better understand the key, basic biological process of how an SGN neurite senses and turns in response to substrate cues. I expect to contribute knowledge to this field by utilizing novel 3D combination micropatterned substrates, real time imaging approaches of the pathways of interest, and a machine learning image sorting model to use an unbiased approach in assessing neurite behavior in response to the micropatterned substrates. These novel insights will inform many aspects of SGN pathfinding through (1) determining if similar fundamental signaling pathways are used by SGNs when turning in response to both biophysical and biochemical cues, (2) clarifying the mechanisms of how the tonotopic organization of the cochlea develops, and (3) though this is not directly a translationally aimed proposal, the findings will also further the goal of inducing organized neurite growth into close proximity to a CI.

项目摘要/摘要 耳蜗利用了复杂的传入神经支配的整理组织，以有效地处理 复杂的听觉刺激。为了创建这种精确组织的模式，来自螺旋神经神经元的神经突 （SGN）导航一个复杂的细胞环境，细胞外基质和生化梯度以达到其 皮尔蒂和耳蜗核器官中的外围和中央靶标。这个神经突的过程 在环境中生长称为探路。在探路中，神经突的尖端，生长锥， 感官，转弯和生长朝着靶向生化和生物物理提示。这提出了 研究的重点是了解不同的底物线索如何（地形，化学吸引力和 Chemorepulsive）可以促进SGN神经突和通过信号通路的转向 依靠执行这个基本的生物学过程。 以前的工作已经确定，工程化的微图案底物可用于两者（1）直接SGN 生长和（2）研究该现象在体外激活的信号传导途径。我们已经证明了 神经元与各种工程图案底物（地形，化学吸引力和 ChemorePulstive）。此外，我们在SGN中牵涉到RhoA-GTPase和钙信号传导 从地形线索出生。我建议使用此工程的微图案底物研究（1） 在决定神经突转的地形和生化线索的层次结构和相互作用和（2） 生长锥以感知和转向这些线索所必需的生化途径。特别是我 将研究趋化吸引力（层粘连蛋白）和化学螺栓（EPHA4）如何与地形生长线索相互作用 当放置在免费（在槽中吸引人）或拮抗作用（在槽中排斥）时。此外， 我将使用药理学和 在各种图案化的底物上生长时，将这些途径的激活成像。 总体而言，这项研究的目的是更好地了解SGN神经突的关键，基本的生物学过程 响应底物线索的感觉和转弯。我希望通过利用小说来为这一领域贡献知识 3D组合微图案底物，感兴趣途径的实时成像方法和A 机器学习图像排序模型以使用公正的方法评估神经突行为 到微图案的基材。这些新颖的见解将为SGN通过（1）提供许多方面。 确定SGN在响应两者时是否使用类似的基本信号通路 生物物理和生化提示，（2）阐明耳蜗的吨位组织的机制 开发，（3）尽管这不是直接的翻译针对提案，但这些发现也将进一步进一步 诱导有组织的神经突的生长与CI紧邻。