DEVELOPMENTAL REGULATION OF NEUROPEPTIDE EXPRESSION

此申请是为了继续我们的研究， 描述了调控表达的发育机制， 神经肽 在Manduca（蛾）胚胎中，我们已经描述了 PheMetArgPhe-酰胺相关神经肽的胚胎表达 （FMRFamide）在中枢、外周和 肠神经系统 我们还分离并表征了 两种昆虫（果蝇和曼陀罗）中的基因， FMRFamide样神经肽。 进一步表征 Manduca基因将提供信息和探针，以补充 胚胎肽能神经元在体内和体外的细胞分析 胚培养 在资助期内，我们会继续发展模型系统， 集中于肽能表型的分化。 我们将 考虑遗传和表观遗传机制对 监管的三个基本方面 分化 第一方面涉及定时机构 在形态发生过程中， 表达（细胞特异性性质）首先在 识别神经元。 第二部分研究了 在已鉴定的神经元中作为瞬时神经肽表达的基础 在胚胎发育过程中。 第三个考虑延迟和位置- 迁移神经元中特异性神经肽的表达 在发育中的肠道中，似乎没有被唯一识别。 对于每一个方面，我们都将从两个方面来研究差异化。 神经肽含量和神经肽基因表达。 为了 把这些观察放在细胞的更大背景下， 分化，超微结构研究的特定神经元， 针对神经肽前体和成熟肽的特异性抗体 肽将在这些阶段的每一个期间进行， 分化 这些研究将为以后的研究提供基础， 调节这三个方面的分子机制 的差异。 此外，它们代表了先行词 实验步骤，以未来考虑细胞 决定，也就是说，细胞和分子机制， 是细胞特异性神经肽模式产生的基础 基因表达。

This application is for a continuation of our studies designed to described development mechanisms that regulate the expression of neuropeptides. In Manduca (moth) embryos, we have described the embryonic expression of neuropeptides related to PheMetArgPhe-amide (FMRFamide) in specific neurons of the central, peripheral and enteric nervous systems. We have also isolated and characterized genes in two insects species (Drosophila and Manduca) that encode the FMRFamide-like neuropeptides. Further characterization of the Manduca gene will provide information and probes to complement the cellular analysis of embryonic peptidergic neurons in vivo and in embryo culture. During the grant period, we will continue to develop model systems to focus on the differentiation of peptidergic phenotypes. We will consider contributions of genetic and epi-genetic mechanisms to the regulation that underlies three fundamental aspects of differentiation. The first aspect pertains to the timing mechanism that dictates when, during morphogenesis, initial neuropeptide expression (a cell-specific property) is first observed in identified neurons. The second investigates the mechanisms that underlie transient neuropeptide expression in an identified neuron during embryogenesis. The third considers delayed and position- specific neuropeptide expression among a group of migrating neurons in the developing gut that do not appear to be uniquely identified. For each aspect, we will study differentiation in terms of both neuropeptide content and neuropeptide gene expression. In order to place these observation within the larger context of cellular differentiation, ultrastructural studies of specific neurons using specific antibodies to the neuropeptide precursor and to the mature peptides will be performed during each of these phases of differentiation. These studies will provide a basis for the later investigation of the molecular mechanisms that mediate these three regulated aspects of differentiation. Further, they represent antecedent experimental steps to the future consideration of cellular determination, that is, the cellular and molecular mechanisms that underlie the generation of cell-specific patterns of neuropeptide gene expression.