In Vivo Analysis of the Mechanisms of Neural Crest Migration

描述（由申请人提供）：最具破坏性的出生缺陷之一影响神经嵴，神经嵴是一种高度迁移的干细胞样群体，有助于颅面和心血管发育以及外周和肠神经系统组装。细胞谱系追踪和组织移植研究表明，神经嵴细胞（NCC）迁移途径是离散的分离流，由无神经嵴的禁区隔开，似乎可以防止NCC亚群的混合，并确保它们到达精确的目标。这些发现支持了神经嵴细胞引导信号来源于胚胎微环境和细胞通讯的前提。最值得注意的是我们在体内产生的数据显示细胞-细胞和细胞-环境相互作用可能会影响神经嵴的定向迁移。基于这些观察结果，我们建议测试中心假设，即与胚胎神经嵴丰富区域相关的微环境和细胞-细胞相互作用包含有可能将细胞定向到精确目标的信息线索。我们的长期目标是了解神经嵴迁移的生物学机制，最终导致器官发育。我们的短期目标是确定在体内模型中塑造颅NCC迁移流的关键细胞和分子机制。使用在体内的分子扰动和胚胎显微手术，连同光活化细胞标记，4-D共聚焦成像，细胞跟踪和细胞行为分析，我们建议：目的1：表征特定的和动态的细胞相互作用至关重要的颅神经嵴迁移使用在体内的光活化细胞标记，4-D共聚焦成像，细胞跟踪和细胞行为分析。目的2：确定胚胎微环境中神经纤毛蛋白在神经嵴迁移信号传导和调节中的作用。目标3：研究胚胎微环境在信号传导和调节神经嵴迁移中的作用，特别关注神经纤毛蛋白-脑信号蛋白和神经纤毛蛋白-VEGF的相互作用。 公共卫生相关性：在这些研究完成后，我们希望有更多的了解指导线索和途径，直接调节神经嵴迁移，可以转化为新的治疗应用。

DESCRIPTION (provided by applicant): One of the most devastating birth defects affect the neural crest, a highly migratory stem cell-like population that contribute to craniofacial and cardiovascular development, and peripheral and enteric nervous system assembly. Cell lineage tracing and tissue transplantation studies have revealed the neural crest cell (NCC) migratory pathways emerge as discrete segregated streams, separated by neural-crest-free exclusion zones that appear to prevent the intermixing of NCC subpopulations and ensure their arrival at precise targets. These findings support the premise that neural crest cell guidance cues derive from the embryonic microenvironment and cell communication. Most noteworthy are the data we have generated in vivo showing cell-cell and cell-environment interactions may influence the directional migration of the neural crest. Based on these observations, we propose to test the central hypothesis that the microenvironment and cell-cell interactions associated with the neural crest-rich regions of the embryo contain informational cues with the potential to direct cells to precise targets. Our long term goal is to understand the biological mechanisms underlying neural crest migration that ultimately results in organ development. Our short term goal is to identify the key cellular and molecular mechanisms underlying the sculpting of cranial NCC migratory streams within an in vivo model. Using in vivo molecular perturbations and embryo microsurgery, together with photoactivation cell labeling, 4-D confocal imaging, cell tracking and cell behavior analyses, we propose to: Aim 1: Characterize the specific and dynamic cellular interactions essential for cranial neural crest migration using in vivo photoactivation cell labeling, 4-D confocal imaging, cell tracking and cell behavior analyses. Aim 2: To determine the role of neuropilins within the embryonic microenvironment in signaling and modulating neural crest migration. Aim 3: Investigate the role of the embryonic microenvironment in signaling and modulating neural crest migration, with particular focus on neuropilin- semaphorin and neuropilin-VEGF interactions. Public Health Relevance: At the completion of these studies, we expect to have an increased understanding of guidance cues and pathways that directly modulate neural crest migration that could be translated for novel therapeutic applications.