COLLAPSIN 1 AND OLFACTORY AXON PATTERNING IN VIVO

体内塌陷蛋白 1 和嗅觉轴突模式

• 批准号: 2522918
• 负责人: ANDREA C MISSIAS
• 金额: $ 2.62万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-06-01 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/2522918
• 关键词: Retroviridae; axon; gene expression; genetically modified animals; immunocytochemistry; laboratory mouse; limbic system; neurotrophic factors; olfactory lobe; olfactory nerve; protein structure function; receptor expression; sensory receptors; Retroviridae; axon; gene expression; genetically modified animals; immunocytochemistry; laboratory mouse; limbic system; neurotrophic factors; olfactory lobe; olfactory nerve; protein structure function; receptor expression; sensory receptors

The long-term objective of this project is to understand the mechanisms by which neuronal projections are shaped. During development, growing axons respond to environmental cues at many points. One such cue, collapsin-1 (coll-1), has been shown to restrict the terminations of specific axon populations by a repulsive mechanism. In the olfactory bulb, coll-1 is initially expressed in a superficial band, during a period when olfactory axons pause at the bulb surface; subsequently, coll-1 expression shifts to deeper layers, and olfactory axons begin to penetrate into the bulb's outer layers. From these preliminary observations, we infer that coll-1 constrains the growth of olfactory endings: specifically, we predict that coll-1 acts early in development to exclude migrating olfactory axons from penetrating into the nascent olfactory bulb, and that later it contributes to the restriction of those axon terminations to a superficial layer. This proposal is designed to test that hypothesis by way of three Specific Aims: first, precisely defining the relationship between changing patterns of coll-1 expression in the developing bulb and the positions of migrating olfactory axons. Second, assessing the effect of ectopically-expressed coll-1 on the growth of these axons into chick olfactory bulb. Third, determining the pattern of olfactory axon trajectories in the absence of coll-1, in knock-out mice. Together these aims will help define the extent to which coll-1 directs the development of olfactory projections.

该项目的长期目标是了解机制 神经元预测的形状。 在发展期间，成长 轴突在许多方面都对环境提示做出反应。 一个这样的提示， Collapsin-1（coll-1）已被证明限制了 特定的轴突种群通过排斥机制。 在嗅觉中 灯泡，coll-1最初在表面上表达 嗅觉轴突在灯泡表面停顿的时期；随后， Coll-1的表达转移到更深的层，嗅觉轴突开始 穿透灯泡的外层。 从这些初步 观察结果，我们推断出Coll-1限制了嗅觉的生长 结局：具体来说，我们预测Coll-1在开发早期起作用 排除迁移的嗅觉轴突渗透到新生 嗅球，后来有助于限制 那些轴突终止呈浅层层。 该提议是 旨在通过三个特定目的来检验该假设：首先 精确地定义了变化的coll-1模式之间的关系 发育中的灯泡和迁移位置的表达 嗅觉轴突。 其次，评估异位表达的效果 这些轴突生长到雏鸡嗅球中。 第三， 在不存在的情况下确定嗅觉轴突轨迹的模式 coll-1，在淘汰小鼠中。这些目标在一起将有助于定义 Coll-1指导嗅觉预测的发展程度。