PLASTICITY OF NEURONAL FUNCTION AND FORM

神经元的电活动是形成 发育中的神经系统中适当的突触连接和 调节成年动物学习过程中的突触效能。生长 神经突起和成熟的突触终末有许多共同的特征， 对这种发育和生理可塑性负责。这 项目检查神经的功能和形态可塑性 终末与电活动对神经元发育的影响 通过使用遗传学、生理学和解剖学的组合 技巧。果蝇突变体DNC，RUT和ALA，每个都影响一个 CAMP和钙调素第二信使系统中的特定步骤， 表现出学习能力下降。此外，几个突变体具有 有缺陷的K+和Na+通道将用于生成不同的图案 自发的活动。这些突变体及其双突变体的研究 两者的结合使我们能够确定神经活动和第二 信使系统相互作用调节轴突生长和突触 可塑性。 我们开发了一种“巨型”果蝇神经元的培养系统，这些神经元来源于 来自细胞分裂受阻的神经母细胞。这些神经元表现出各种各样的 正常神经元的分支模式和电活动，但 它们增大的大小极大地促进了生理和细胞 果蝇突变体的生物学研究。实地调查 终末流产和突触传递将在 幼虫的神经肌肉连接。这些运动神经轴突终末显示 依赖活动的可塑性，并提供了一个独特的机会 个体层面的生理和形态分析 突触突触。 拟议研究的结果将为以下方面提供有用的信息 学习和记忆行为的细胞机制以及 功能可塑性和发育可塑性的共同调节机制 在神经系统中。

Neuronal electric activity is the major factor that shapes the appropriate synaptic connectivity in a developing nervous system and regulates synaptic efficacy during learning in adult animals. Growing neurites and mature synaptic terminals share many common features and are responsible for such developmental and physiological plasticity. This project examines the functional and morphological plasticity of nerve terminals and the influence of electric activity on neuronal development by using a combination of genetic, physiological and anatomical techniques. The Drosophila mutants dnc, rut, and ala, each affects a specific step in the cAMP and Ca-calmodulin second messenger systems, show diminished learning ability. In addition, several mutants with defective K+ and Na+ channels will be used to generate different patterns of spontaneous activity. Studies of these mutants and their double mutant combinations allow us to determine how nerve activity and second messenger systems interact to regulate neurite outgrowth and synaptic plasticity. We have developed a culture system of "giant" Drosophila neurons derived from cell division-arrested neuroblasts. These neurons display a variety of branching patterns and electric activity seen in normal neurons but their increased size greatly facilitates the physiological and cell biological investigations of Drosophila mutants. In situ studies of terminal aborization and synaptic transmission will be performed on larval neuromuscular junctions. These motor axonal terminals exhibit activity-dependent plasticity and offer a unique opportunity for physiological and morphological analysis at the level of individual synaptic boutons. Results from the proposed studies will provide useful information about the cellular mechanisms underlying learning and memory behavior and the regulatory mechanisms common to functional and developmental plasticity in the nervous system.