Investigation of Armadillo/ß-catenin Mechanisms Influencing Nociceptive Sensitivity in Drosophila

项目概要 正常疼痛通过警告我们潜在的组织损伤来促进健康，但异常疼痛会降低质量 世界各地数百万人的生活。目前可用的疼痛治疗方法不足，部分原因是 我们最好的镇痛药阿片类药物的有害副作用。对异常疼痛的更好治疗方法很糟糕 需要。我们建议通过利用强大的遗传工具包来揭示止痛药的新靶点 果蝇模型。果蝇幼虫对有害刺激做出反应，其逃避行为包括： 明显无误的螺旋卷。该模型系统已用于识别数十个调节组件 伤害感受敏感性。在果蝇中发现的许多信号成分与其哺乳动物非常相似 同行。初步结果表明，B-连环蛋白的果蝇同源物，称为犰狳 (Arm) 调节 伤害感受敏感性，但目前尚不清楚这种调节机制。目标 1 将检验假设 Arm 通过影响众所周知的 Wnt/Wg 转录控制来调节敏感性 途径。该测试将通过针对关键的 RNAi 沉默和/或过度表达构建体来完成 使用 Gal4/UAS 系统特异针对伤害感受器神经元的途径基因。任何由此产生的更改 伤害感受敏感性将在专注于逃避的热和机械伤害感受测定中观察到 行为。目标 2 将检验 Arm 和相关组件调节伤害感受的独立假设 通过 Arm 的细胞粘附功能提高灵敏度。我们将使伤害感受器表达 Arm 的标记形式 以及其他可以通过免疫荧光显微镜分析来研究神经元 Arm 的成分 对称为鞘的神经元-表皮粘附连接以及与中枢神经系统中间神经元的突触的贡献。 我们将低估和过度表达 Arm 和其他组件，并将鞘或突触的任何变化关联起来 使用我们的行为分析形成伤害性敏感性。拟议的研究有可能 确定影响伤害敏感性的新机制和成分。由于学历高 果蝇和哺乳动物信号分子之间的功能保守性，这些分子鉴定的成分 实验可能代表治疗人类异常疼痛的新药物的目标。

Project Summary Normal pain promotes health by warning us of potential tissue damage, but abnormal pain reduces the quality of life for millions around the world. Available treatment for pain is currently inadequate, in part because of the deleterious side effects of our best analgesics, the opioids. Better treatments for abnormal pain are badly needed. We propose to reveal novel targets for pain medications by exploiting the powerful genetic toolkit of the Drosophila model. Fruit fly larvae react to noxious stimuli using an escape behavior consisting of an unmistakable corkscrew roll. This model system has been used to identify dozens of components that regulate nociceptive sensitivity. Many signaling components identified in the fly are very similar to their mammalian counterparts. Preliminary results indicate that the fly homolog of B-catenin, called Armadillo (Arm) regulates nociceptive sensitivity but the mechanism of this regulation is currently unclear. Aim 1 will test the hypothesis that Arm regulates sensitivity by exerting its influence in the well-known Wnt/Wg transcriptional control pathway. This testing will be accomplished by targeting RNAi silencing and/or overexpression constructs of key pathway genes specifically to the nociceptor neurons using the Gal4/UAS system. Any resulting changes to nociceptive sensitivity will be observed in thermo- and mechanonociception assays that focus on the escape behavior. Aim 2 will test the independent hypothesis that Arm and related components regulate nociceptive sensitivity through Arm's cell adhesion function. We will cause the nociceptors to express tagged forms of Arm and other components that can be analyzed by immunofluorescent microscopy to study neuronal Arm's contribution to neuronal-epidermal adhesive junctions called sheaths and to synapses with CNS interneurons. We will under- and overexpress Arm and other components and correlate any changes in sheath or synapse formation with nociceptive sensitivity using our behavioral assays. The proposed studies have the potential to identify novel mechanisms and components that affect nociceptive sensitivity. Because of the high degree of functional conservation between fly and mammalian signaling molecules, components identified by these experiments may represent targets for novel medications for the treatment of abnormal pain in humans.