Neural Development: Intercellular and Humoral Control

五个参与的研究小组在理解细胞间和激素信号的重要性和机制方面有着共同的兴趣，这些信号调节神经元的胚胎后发育和可塑性。在过去的13年里，这些小组之间日益增长的合作，以及对控制神经系统内发育可塑性的机制的日益关注，导致了该计划项目的出现和持续成功。这些实验室代表的研究领域包括：短距离和接触介导的细胞间影响在神经发育中的作用和机制；激素调控运动神经元和中间神经元的胚胎后分化和重塑；突触形成在神经系统发育中的超微结构和生理方面；神经胶质细胞在中枢神经系统有组织神经束发育中的作用；类固醇激素调节神经元发育的分子机制。参与者将对五个组成部分的机制展开多学科、高度协作的研究，这些项目包括：(1)参与相关学习的大脑高度有序区域的胚胎后发育；(2)嗅觉感受器神经元分类和嗅觉通路发育过程中神经胶质-神经元相互作用的分析；(3)体内和原代细胞培养中已确定的运动神经元发育的类固醇激素调节；(4)类固醇激素反应基因的分子和遗传学分析及其在中枢神经系统发育中的作用；(5)男性特有的嗅觉轴突对特化嗅球发育的影响及嗅觉轴突的信号传递机制。所有建议的研究都是基于使用经济的、容易获得的、实验上有利的无脊椎动物模型系统。由于许多研究人员，包括本计划项目的参与者，对昆虫制剂进行了广泛的研究，因此拟议研究中使用的昆虫制剂特别容易理解，并有利于这些实验。具体地说，Manduca和蟑螂提供了很好的获得生理和激素机制的途径，而果蝇提供了一系列强大的分子和遗传途径。发展的基本机制在进化过程中是保守的。因此，我们预计，从这些项目中获得的关于昆虫神经和肌肉发育的信息将有助于阐明包括人类在内的其他动物的相关现象。

The five participating research groups share a common interests in understanding the importance and mechanisms of intercellular and hormonal signals that regulate the post-embryonic development and plasticity of neurons. Growing collaboration among these groups over the past 13 years and increasing mutual focus on the mechanisms that control d4evelopmental plasticity within the nervous system have led to the emergence and continued success of this Program Project. Among the research areas represented by these laboratories are: the roles and mechanisms of short-distance and contact-mediate intercellular influences in neural development; hormonally regulated post-embryonic differentiation and remodeling of motor neurons and interneurons; ultrastructural and physiological aspects of synapse formation in developing neural systems; the role of glial cells in the development of organized neuropil in the central nervous system; and molecular mechanisms of steroid hormone regulation of neuronal development. The participants will mount multi-disciplinary, highly collaborative investigations of mechanisms underlying five component projects include: (1) the post-embryonic development of a highly-ordered region of the brain that is involved in associated learning; (2) analysis of glial- neuronal interactions in olfactory receptor neuron sorting and in formation of glomerular compartments during development of olfactory pathways; (3) steroid-hormonal regulation of development of identified motor neurons in vivo and in primary cell culture; (4) molecular and genetic analysis of steroid hormone responsive genes and their roles in CNS development; and (5) influence of male-specific olfactory sensory axons on the development of a specialized olfactory glomerulus and mechanisms of signaling by olfactory axons. All of the proposed studies are based on the use of invertebrate model systems that are economical readily Available, and experimentally favorable. Because they have been extensively studied by many investigators, including the participants in this program project, the insect preparations to be used in the proposed studies are especially well understood and favorable for these experiments. Specifically, Manduca and the cockroach offer excellent access to physiological and hormonal mechanisms, whereas Drosophila offers a powerful array of molecular and genetic approaches. The basic mechanisms of development have been conserved during evolution. We expect, therefore, that information obtained in these projects about neural and muscular development in insects will illuminate related phenomena in other animals including human beings.