DEVELOPMENT OF ADULT-SPECIFIC BEHAVIOR IN MANDUCA SEXTA

一个重要且相对较新的概念出现在 关于神经网络的功能组织的神经科学 以及这样的系统如何产生有节奏的行为。突出的特点是 这一概念的核心是神经网络具有能力和可塑性 生成各种图案化输出，具体取决于 神经网络接收的化学和/或突触输入。 重要的是，“保护-调制”策略也可以被 神经系统产生越来越复杂的行为 在发育后期表达。据认为， 脊椎动物成体特有的运动行为的发展可能是 基于这样的战略。 这项拟议的研究将检查发育中的中枢神经系统。 全天星天牛的发育情况 成人行为的构建似乎是基于 神经回路的神经调节存在于发育早期 各阶段。拟议的研究将检查细胞和 成人蜕皮症潜在的神经元素的发育方面 荷尔蒙激活的节律性行为，使昆虫能够逃脱 从它的旧角质层。之前的实验表明，幼虫 蜕皮运动模式可以在成人中显露出来。它在中国的保留 成人被认为是导致新的成人特有的蜕皮的原因。 图案。由于神经活动下降的影响，在某些情况下 未知的方式，保守的幼虫蜕皮模式产生电路 会产生成年蜕皮行为。初步研究 表示在一组大约15对下行信号中 胸腺神经元，有必要进行修饰的中间神经元 将幼虫蜕皮运动程序转化为 成人特有的一种。我建议：(1)研究 单个下行中间神经元在脑内神经递质的转化中发挥作用 幼虫的蜕皮型与成虫型的蜕皮型，以及(2)检查 胸椎下行中间神经元的发育史和 这些神经元与保守的幼虫建立了解剖联系 成人体内的回路。细胞内外电生理 方法将被用来研究下行中间神经元的活动。 关于已识别的蜕皮输出--运动神经元和可能的其他 中间神经元。各种细胞示踪剂将被用来研究 下行的胸椎间神经元，特别是在变态期间 发展。这是第一个开发的无脊椎动物模型系统 在那里，可以在细胞水平上研究成年人的行为 起因于前面表达的运动程序的明显调制 正在开发中。

An important and relatively recent concept has arisen in the neurosciences regarding the functional organization of neural networks and how such systems generate rhythmic behaviors. The salient feature of this concept is that a neural network has the capacity and plasticity to generate various patterned outputs, depending on the specific chemical and/or synaptic inputs the neural network receives. Importantly, the "conservation-modulation" strategy may also be used by the nervous system for the generation of increasingly complex behaviors expressed at later developmental stages. It is thought that the development of adult-specific locomotor behaviors in vertebrates may be based on such a strategy. The proposed research will examine the developing central nervous system of the holometabolus insect, Manduca sexta, where developmental construction of adult behavior appears to be based on the neuromodulation of neural circuitry present at earlier developmental stages. The proposed research will examine the cellular and developmental aspects of neural elements underlying adult ecdysis, a hormonally activated rhythmic behavior that enables the insect to escape from its old cuticle. Previous experiments indicate that the larval ecdysis motor pattern can be un-masked in the adult. Its retention in the adult is thought to contribute to the novel adult-specific ecdysis pattern. By the influence of descending neural activity, in some unknown way, the conserved larval ecdysis pattern-generating circuitry is acted upon to produce adult ecdysis behavior. Preliminary studies indicate that within a group of approximately 15 pairs of descending thoracic neurons, there are modifying interneurons that are necessary for the transformation of the larval ecdysis motor program into the adult-specific one. I propose to: (1) examine the functional role that individual descending interneurons play in the transformation of the larval ecdysis pattern to that of the adult pattern, and (2) examine the developmental history of descending thoracic interneurons, and the anatomical connections these neurons make with the conserved larval circuitry in the adult. Intra- and extracellular electrophysiological methods will be used to study the actions of the descending interneurons on identified ecdysis out-put motoneurons and possibly other interneurons. Various cell tracers will be used to study the anatomy of the descending thoracic interneurons, especially during metamorphic development. This is the first invertebrate model system developed where it is possible to study, at the cellular level, how adult behavior arises from the apparent modulation of a motor program expressed earlier in development.