DEVELOPMENT OF SYNAPSES BETWEEN IDENTIFIED NEURONS

神经系统组织的本质是建立 突触回路 需要大量的精确度， 这些回路的构建，以及许多行为障碍， 发生在人类和其他动物身上的疾病是由于 突触连接的发展。 这一长期目标 研究旨在阐明基本的细胞和分子机制， 是形成和维持特定突触连接的基础， 使用蟑螂的末端神经节作为模型系统。 许多 控制神经元发育其他方面的机制 在整个进化过程中是保守的，这使得它很可能 这项工作将有助于我们最终了解我们的 自己的大脑被组装起来。 该项目的第一个具体目标是 确定突触形成的顺序和特异性， 在胚胎发育过程中识别神经元，使用细胞内 记录、染料注入以及光学和电子显微镜。 第二 目的是评估颈传入神经再生的准确性 它们的树枝状结构和突触连接， 细胞内记录、染料注射和形态测定分析。 的 第三个具体目标是确定生理和解剖学基础 突变蟑螂的突触竞争， 突触前神经元，使用量子分析和 定量电子显微术 细胞内染料注射将是 用于确定额外轴突是否在 终末神经节比正常的轴突。 同步的效果 将研究相对突触功效上的再生。 细胞内记录和染料注射将被用来追求 本项目的第四个目标：确定竞争力的作用 在遗传野生型的胚后发育期间的相互作用 动物

The essence of nervous system organization is the establishment of synaptic circuits. A great deal of precision is demanded in the construction of these circuits, and many of the disorders of behaviour that occur in humans and other animals are due to abnormalities in the development of synaptic connections. The long-term objectives of this research are to elucidate basic cellular and molecular mechanisms which underlie the formation and maintenance of specific synaptic connections, using the terminal ganglion of the cockroach as a model system. Many of the mechanisms which control other aspects of neuronal development have been shown to be conserved throughout evolution, which makes it likely that this work will contribute to our eventual understanding of how our own brains are assembled. The first specific aim of this project is to determine the sequence and specificity of synapse formation between identified neurons during embryonic development, using intracellular recording, dye injection and light and electron microscopy. The second aim is to assess the accuracy with which cercal afferents regenerate their arborization and synaptic connections, using a combination of intracellular recording, dye injection, and morphometric analysis. The third specific aim is to determine the physiological and anatomical basis for synaptic competition in mutant cockroaches with a supernumerary presynaptic neuron, using a combination of quantal analysis and quantitative electron microscopy. Intracellular dye injection will be used to find out whether the supernumerary axon arrives later in the terminal ganglion than the normal axons. The effect of synchronized regeneration on the relative synaptic efficacies will be investigated. Intracellular recording and dye injection will be used to pursue the fourth aim of this project; to determine the role of competitive interactions during postembryonic development of genetically wild-type animals.