CYTOSKELETAL REGULATION DURING GROWTH CONE GUIDANCE

描述（由申请人提供）：在胚胎发育过程中，大量神经元必须与其适当的目标形成连接。轴突被生长锥引导到它们的目标，生长锥将引导信号整合并转化为运动所需的机械力。运动源于细胞骨架聚合物和相关蛋白的动态调节。Ena/VASP蛋白家族在各种轴突引导通路中起作用，并调节肌动蛋白丝的组装。Ena/VASP蛋白集中在生长锥丝状足的尖端，那里是对引导信号的初始反应发生的地方。参与轴突引导的几个信号通路调节Ena/VASP功能。因此，Ena/VASP蛋白很好地定位为来自引导通路和肌动蛋白细胞骨架的信号之间的关键汇聚点。我们将验证Ena/VASP蛋白在响应引导信号时调节肌动蛋白重塑的假设。我们建议使用高分辨率光镜和电子显微镜分析细胞骨架动力学和几何结构来研究Ena/VASP在生长锥引导和易位中的作用。我们还将采用遗传操作来干扰Ena/VASP功能和生化方法来研究Ena/VASP在信号通路中的作用。这项工作将对神经系统如何发育以及如何设计损伤后修复神经系统的方法提供有价值的见解。

DESCRIPTION (provided by applicant): During embryonic development, vast numbers of neurons must form connections with their proper targets. Axons are guided to their targets by growth cones, which integrate and convert guidance signals into mechanical forces required for locomotion. Movement arises from dynamic regulation of cytoskeletal polymers and associated proteins. The Ena/VASP protein family functions in various axon guidance pathways and is known to regulate the assembly of actin filaments. Ena/VASP proteins are concentrated in the tips of growth cone filopodia, where the initial response to guidance signals occurs. Several signaling pathways implicated in axon guidance regulate Ena/VASP function. Therefore, Ena/VASP proteins are well positioned to act as key convergence points between signals from guidance pathways and the actin cytoskeleton. We will test the hypothesis that Ena/VASP proteins regulate actin remodeling in response to guidance signals. We propose to examine the role of Ena/VASP in growth cone guidance and translocation using high-resolution light and electron microscopy to analyze cytoskeletal dynamics and geometry. We will also employ genetic manipulation to perturb Ena/VASP function and biochemical approaches to study Ena/VASP's role in signaling pathways. This work should yield valuable insight into how the nervous system develops and how to design methods to repair it after injury.