Cellular and Molecular Mechanisms of Forebrain Axon Pathfinding Defects in FASD

FASD 前脑轴突寻路缺陷的细胞和分子机制

• 批准号: 10017119
• 负责人: Carlita Favero
• 金额: $ 15.56万
• 依托单位: URSINUS COLLEGE
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-15 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10017119
• 关键词: Age; Alcohol consumption; Alcohols; Animal Model; Area; Awareness; Axon; Brain; Brain Diseases; Cell Count; Cell Culture Techniques; Cells; Coculture Techniques; Commissure; Corpus Callosum; Cues; Defect; Development; Distal; Dorsal; Dyes; Dysmorphology; Ensure; Environment; Ethanol; Exhibits; Face; Family; Fetal Alcohol Exposure; Fetal Alcohol Spectrum Disorder; Goals; Hippocampus (Brain); Human; Hybrids; Impairment; In Situ; In Vitro; Internal Capsule; Length; Ligands; Measures; Mediating; Mentors; Messenger RNA; Methods; Molecular; Molecular Target; Motor; Mus; Nature; Nervous system structure; Optic Nerve; Outcome; Output; Pathway interactions; Preoptic Areas; Process; Prosencephalon; Protein Isoforms; Recording of previous events; Reporting; Research; Reverse Transcriptase Polymerase Chain Reaction; Rodent; Role; Science; Sensory; Signal Pathway; Signal Transduction; Source; Stimulus; Structure; Telencephalon; Testing; Thalamic structure; Time; Western Blotting; Width; Woman; Work; alcohol effect; alcohol exposure; anterior commissure; axon growth; axon guidance; axonal pathfinding; base; career; cell motility; child bearing; embryo disorder; experimental study; in vivo; information processing; interest; migration; mouse model; myelination; nerve stem cell; neuropathology; novel; offspring; oligodendrocyte precursor; pregnant; receptor; relating to nervous system; success; undergraduate student; white matter

PROJECT SUMMARY Despite public awareness campaigns, Fetal Alcohol Spectrum Disorders (FASD) remain prevalent due to alcohol consumption by women who are pregnant or of child-bearing age. It is well appreciated that sensory and motor information processing is distorted in FASD, but alcohol effects on the thalamus, which likely mediates these functions, have not been widely investigated. Prenatal alcohol exposure (1) disrupts axonal connections between the thalamus and cortex which are required to appropriately receive and respond to sensory cues in the environment, (2) damages the ventral telencephalon (vTel), a critical intermediate target for proper development of these connections, and (3) alters guidance cues and signaling pathways that underlie cell and axon migration. We hypothesize that moderate alcohol exposure disrupts the Slit/Robo pathway, a family of guidance cues and receptors that can have both direct and indirect effects on forebrain axon formation. In this proposal we will investigate corridor-cell mediated thalamocortical axon (TCA) guidance into and within the vTel using a mouse model of FASD. Our experiments aim to (1) define the nature of TCA and corridor cell guidance errors in FASD and (2) establish Slit and Robo as molecular targets of FASD neuropathology in vivo. To analyze TCA guidance errors, we will use dye tracing and immunostaining to visualize these axons along their trajectory. To evaluate corridor cells, we will count and determine the distribution of these cells via immunostaining. To analyze alcohol-induced perturbations of Slit and Robo expression in vivo, we will perform western blotting and RT-PCR for each isoform. We will also use in vitro explant co-cultures to test Slit and Robo function. In the FASD brain, we expect TCAs to project inappropriately to intermediate and final targets and the corridor to be malformed. We also predict that Slit/Robo expression and function will be suppressed. Our findings will reveal the impact of moderate alcohol exposure on guidance mechanisms that are required for proper nervous system wiring, an area that is currently understudied. This work will also enhance understanding of cellular and molecular mechanisms that are likely to be involved in sensorimotor processing defects observed in human FASD. The proposed experiments will largely be carried out by undergraduates who will be mentored to provide them the guidance and expertise needed for success in science careers and graduate work.

项目概要 尽管开展了公众宣传活动，胎儿酒精谱系障碍 (FASD) 仍然普遍存在，原因是 怀孕或育龄妇女饮酒。人们普遍认为，感官 胎儿酒精谱系障碍 (FASD) 中运动信息处理被扭曲，但酒精会影响丘脑，这可能 介导这些功能，尚未得到广泛研究。产前酒精暴露 (1) 扰乱轴突 丘脑和皮质之间的连接需要适当地接收和响应 环境中的感觉线索，(2) 损害腹侧端脑 (vTel)，这是一个关键的中间目标 为了这些连接的正确发展，以及（3）改变指导线索和信号传导途径 是细胞和轴突迁移的基础。我们假设适度的酒精暴露会扰乱 Slit/Robo 通路，一系列可以对前脑产生直接和间接影响的引导线索和受体 轴突形成。在本提案中，我们将研究走廊细胞介导的丘脑皮质轴突（TCA）引导 使用 FASD 小鼠模型进入 vTel 并在 vTel 内进行。我们的实验旨在 (1) 定义 TCA 的性质 和 FASD 中的走廊细胞引导错误，以及（2）将 Slit 和 Robo 确立为 FASD 的分子靶点 体内神经病理学。为了分析 TCA 引导误差，我们将使用染料示踪和免疫染色来分析 沿着它们的轨迹可视化这些轴突。为了评估走廊单元，我们将计算并确定 通过免疫染色观察这些细胞的分布。分析酒精引起的 Slit 和 Robo 扰动 体内表达后，我们将对每种异构体进行蛋白质印迹和 RT-PCR。我们还将在体外使用 外植体共培养以测试 Slit 和 Robo 功能。在 FASD 大脑中，我们预计 TCA 会做出不恰当的投射 中间和最终目标以及走廊的畸形。我们还预测 Slit/Robo 表达 并且功能会受到抑制。我们的研究结果将揭示适度饮酒对指导的影响 神经系统正常连接所需的机制，目前尚未得到充分研究。这 这项工作还将增强对可能涉及的细胞和分子机制的理解 在人类 FASD 中观察到的感觉运动处理缺陷。拟议的实验将主要进行 由本科生提供，他们将接受指导，为他们提供成功所需的指导和专业知识 在科学职业和研究生工作中。