Neural Development: Intercellular and Humoral Control

五个参与研究小组在理解调节神经元胚胎后发育和可塑性的细胞间和激素信号的重要性和机制方面有着共同的兴趣。在过去的13年中，这些团体之间的合作日益增加，并且越来越多地共同关注控制神经系统内发育可塑性的机制，这导致了该计划项目的出现和持续成功。这些实验室所代表的研究领域包括：神经发育中短距离和接触介导的细胞间影响的作用和机制;运动神经元和中间神经元的胚胎后分化和重塑;发育中神经系统突触形成的超微结构和生理学方面;神经胶质细胞在中枢神经系统有组织神经元发育中的作用;以及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项目的机制进行多学科、高度合作的研究，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）分析嗅觉受体神经元分选中的胶质-神经元相互作用和嗅觉通路发育过程中肾小球隔室的形成;（3）类固醇激素对体内和原代细胞培养中已鉴定的运动神经元发育的调节;（4）类固醇激素应答基因的分子和遗传分析及其在CNS发育中的作用;和（5）雄性特异性嗅觉感觉轴突对特化嗅觉肾小球发育的影响和嗅觉轴突的信号传导机制。所有提出的研究都是基于无脊椎动物模型系统的使用，这些系统经济易得，并且实验上有利。因为它们已经被许多研究人员广泛研究，包括本计划项目的参与者，所以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。具体来说，曼陀罗和蟑螂提供了很好的生理和激素机制，而果蝇提供了一系列强大的分子和遗传方法。基本的发育机制在进化过程中一直保持不变。因此，我们期望，在这些项目中获得的有关昆虫神经和肌肉发育的信息将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.