DEVELOPMENT OF SEXUALLY DIMORPHIC OLFACTORY GLOMERULI

性二态性嗅球的发育

• 批准号: 6243679
• 负责人: JOHN G HILDEBRAND
• 金额: $ 10.66万
• 依托单位: UNIVERSITY OF ARIZONA
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-07-01 至 1998-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6243679
• 关键词: Manduca; central neural pathway /tract; developmental neurobiology; experimental brain lesion; gender difference; glia; histogenesis; histology; hormone regulation /control mechanism; intercellular connection; neural information processing; neural plasticity; neuroendocrine system; neurogenesis; olfactory lobe; pheromone; sensory receptors; sensory signal detection; tissue /cell culture

An important challenge in developmental neurobiology is to unravel mechanisms responsible for the influences exerted by afferent innervation on the development of its targets. Good examples of such phenomena are found in the olfactory system. In the brains of all species studied to date, development of the primary olfactory center with its characteristic array of synaptic glomeruli depends dramatically on innervation by primary- afferent axons of olfactory receptor cells. How sensory axons control the formation of glomeruli, and how odotopy -- the orderly spatial representation of attributes of odor molecules -- arises in the glomerular array, are pressing problems. This project will focus on the development of individual glomeruli and their uniglomerular projection neurons, endowed with characteristic "molecular receptive range" properties and will take advantage of a remarkable model system, the sexually dimorphic olfactors lobe in the brain of Manduca sexta. In particular, we will investigate the postembryonic development of the prominent macroglomerular complex in the male's olfactory lobes. This unique complex receives primary-afferent inputs solely from male-specific olfactory receptor cells, which induce the formation of the macroglomerular complex and are specialized to detect individual components of the female's sex-pheromone blend. The complex comprises two glomerular substructures, each of which receives and processes primary-afferent input about a different one of the two key components of the blend. These identified, odotopically defined glomeruli also contain neurites of male-specific central neurons, most notably uniglomerular projection neurons, which participate in specialized synaptic circuitry for processing sensory input about pheromone. As specific aims, the proposed studies ask: (1) how the macroglomerular complex develops, (2) what role(s) glial cells play in its development, (30 whether there are quantitative and temporal requirements for male-afferent control of its development, and (4) whether male-specific sensory axons have molecular specializations that might be responsible for induction of the macroglomerular complex. The ultimate goals of the line of research represented by this proposal are; (a) to ascertain the cellular and molecular mechanisms underlying the decisive role of sensory axons in the development of glomeruli, (b) to discover how primary-afferent and central elements ultimately destined to have similar, distinctive molecular receptive ranges come to associate with each other, and (c) to determine whether glial cells participate in the development of all of the glomeruli in a particular species. This is the first effort, in any species, to ascertain developmental processes and mechanisms underlying morphogenesis of anatomically identified olfactory glomeruli with known functional specificity. This research promises to add significantly to understanding of cell-cell interactions in the development of functionally specialized, modular neuropil in the central nervous system and thus to fuel progress toward improved understanding and treatment of developmental disorders of sensory systems.

发展神经生物学的一个重要挑战是解开 传入神经影响的机制 关于其目标的发展。这种现象的很好的例子是 在嗅觉系统中被发现。在所有被研究的物种的大脑中 初级嗅觉中枢的历史、发展及其特点 突触小球的排列极大地依赖于初级- 嗅觉感受器细胞的传入轴突。感觉神经轴突是如何控制 肾小球的形成，以及如何正统--有序的空间 气味分子属性的表征--出现在肾小球 阵列，是迫在眉睫的问题。 该项目将专注于单个肾小球的发育和 它们的单球投射神经元，被赋予了 “分子接受范围”特性，并将利用 卓越的模型系统，大脑中的性二态嗅觉因子叶 曼杜卡六叶草(Manduca sexta.)特别是，我们将研究胚胎后 男性巨大肾小球复合体的发育 嗅叶。这个独特的复合体接受初级传入输入 完全来自男性特有的嗅觉感受器细胞，这种细胞可以诱导 大肾小球复合体的形成，并专门检测 雌虫性信息素的个别成分混合在一起。情结 包括两个肾小球亚结构，每个亚结构分别接收和 处理有关两个键中不同键的主传入输入 混合物的成分。这些已识别的、按传统定义的肾小球 也含有男性特有的中枢神经突起，最值得注意的是 参与特化突触的单球投射神经元 处理有关信息素的感觉输入的电路。 作为具体目标，拟议的研究问：(1)大肾小球如何 复合体发育，(2)(S)神经胶质细胞在其发育中扮演什么角色，(30) 男性传入是否有数量和时间上的要求 对其发育的控制，以及(4)男性特有的感觉神经轴突 分子的专门化可能是导致 大肾小球复合体。这一研究领域的最终目标 本提案所代表的是：(A)确定蜂窝和 感觉轴突起决定作用的分子机制 肾小球的发育，(B)发现初级传入和中枢 元素最终注定会有相似的、独特的分子 接受范围变得相互关联，以及(C)确定 神经胶质细胞是否参与所有肾小球的发育 在一个特定的物种中。 在任何物种中，这是第一次努力确定发育 解剖学上形态发生的过程和机制 鉴定出具有已知功能特异性的嗅觉小球。这 研究承诺大大增加对细胞-细胞的了解 功能专业化、模块化开发中的相互作用 中枢神经系统中的神经膜，从而推动 提高对感觉发育障碍的认识和治疗 系统。