Analgesic Signaling in Drosophila

果蝇的镇痛信号

• 批准号: 10640993
• 负责人: MICHAEL J GALKO
• 金额: $ 40.5万
• 依托单位: UNIVERSITY OF TX MD ANDERSON CAN CTR
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-15 至 2027-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10640993
• 关键词: Absence of pain sensation; Acids; Acute; Afferent Neurons; Analgesics; Animals; Area; Basic Science; Behavioral; Binding; Biochemical; Biological; Biological Assay; Biology; Calcium; Candidate Disease Gene; Cells; Chemicals; Clinical; Complement; Constipation; Data; Development; Dissection; Dose; Drosophila genus; Exhibits; Fentanyl; G Protein-Coupled Receptor Signaling; G-Protein-Coupled Receptors; Gene Expression Profiling; Genes; Genetic; Goals; Hand; Health; Human; Image; Injury; Ion Channel; Knowledge; Larva; Ligands; Mechanics; Mediating; Mediator; Modality; Modeling; Molecular; Morphine; Morphine Receptors; Naloxone; Neurons; Neuropeptides; Nociception; Opioid; Opioid Peptide; Opioid Receptor; Organism; Orthologous Gene; Pain; Pathway interactions; Peptides; Peripheral; Phenotype; Physiological; Reporter; Research Project Grants; Sensory; Signal Pathway; Signal Transduction; Speed; Stimulus; System; Testing; Tissues; Touch sensation; Trauma; Vertebrates; Withdrawal; Work; antinociception; base; behavioral response; clinical practice; endogenous opioids; feeding; fighting; fly; gene conservation; gene discovery; gene function; genetic analysis; genetic approach; health practice; improved; model organism; morphine administration; morphine tolerance; nociceptive response; novel; receptor; receptor binding; response; side effect; somatostatin receptor 2; tissue injury; tool

Analgesia, the dampening of nociceptive responses to noxious stimuli capable of damaging tissues, is an adaptive behavioral response for organisms- allowing them to feel less pain in physiologically appropriate situations such as physical trauma or the fight/flight response. Analgesia has traditionally been studied in vertebrate models, where endogenous opioid peptides bind to their cognate receptors to dampen behavioral responses to painful stimuli. Genetically tractable model organisms such as Drosophila have recently been used to explore the molecular/genetic bases of nociception and nociceptive sensitization following tissue injury but have not yet been used to dissect conserved analgesia signaling. Drosophila offer both speed of genetic analysis and a variety of sophisticated genetic tools for analyzing gene expression and function that should prove a valuable complement to existing experimental paradigms for the study of analgesia. Our long-term goal in this basic research project is to identify and characterize analgesic signaling pathways in Drosophila larvae. That such pathways are likely to exist is evidenced by our preliminary findings that the opiate compound morphine is analgesic for Drosophila larvae and that a conserved G-protein coupled receptor (GPCR) is required in this organism for thermal analgesia. Morphine feeding to fly larvae causes transient analgesia that spans multiple sensory modalities (heat, cold, touch, chemical), is mimicked by other opiates (fentanyl) and is partially naloxone reversible. Our short-term goals over the initial project period will be to characterize the GPCR required for thermal analgesia. Using our knowledge of which tissues express the GPCR we will determine which tissues functionally require it for analgesia, and assess whether the putative receptor’s analgesic effects extend to other sensory modalities beyond heat. At the biochemical level we will test whether the GPCR (and it’s clearest human ortholog) directly binds morphine to activate signaling. At the genetic level we will identify endogenous peptide ligand(s) and probe genetic interactions with previously identified nociceptive genes and nociceptive sensitization signaling pathways. In our final aim we will probe cellular effects of morphine administration (calcium changes) and whether known deleterious biological side effects of morphine, development of tolerance and constipation are also observed in our new model. Successful completion of these aims will provide a comprehensive cellular and genetic analysis of analgesic signaling in this new model- basic information that is likely to generate testable hypotheses for ongoing work in vertebrate models. Moving forward, this new model of analgesic signaling will provide the possibility of unbiased gene discovery approaches that should allow for identification of novel conserved genes required for analgesia- targets that may in some cases be potentially relevant to human and health and worthy of further exploration in vertebrate models and clinical settings.

镇痛是抑制对能够损伤组织的有害刺激的伤害性反应。 生物体的适应性行为反应——让它们在生理上适当的情况下感受到更少的疼痛 身体创伤或战斗/逃跑反应等情况。镇痛传统上的研究 脊椎动物模型，内源性阿片肽与其同源受体结合以抑制行为 对疼痛刺激的反应。最近使用了果蝇等遗传易处理的模型生物 探索组织损伤后伤害感受和伤害感受敏化的分子/遗传基础，但 尚未用于剖析保守的镇痛信号传导。果蝇提供两种速度的遗传分析 以及各种用于分析基因表达和功能的复杂遗传工具，这些工具应该证明 对镇痛研究现有实验范式的宝贵补充。我们在这方面的长期目标 基础研究项目是鉴定和表征果蝇幼虫的镇痛信号通路。那 我们的初步发现证明了这种途径很可能存在，即阿片类化合物吗啡是 果蝇幼虫的镇痛剂，并且该过程需要保守的 G 蛋白偶联受体 (GPCR) 热镇痛有机体。给蝇幼虫喂食吗啡会导致短暂的镇痛，这种镇痛会持续多个时间 感觉方式（热、冷、触觉、化学），被其他阿片类药物（芬太尼）模仿，并且部分是纳洛酮 可逆。我们在项目初始阶段的短期目标是表征 GPCR 所需的特征 热镇痛。利用我们对哪些组织表达 GPCR 的了解，我们将确定哪些组织 功能上需要它来镇痛，并评估假定受体的镇痛作用是否延伸到其他 热以外的感觉方式。在生化水平上，我们将测试 GPCR（以及它是最清晰的人类 直向同源物）直接结合吗啡以激活信号传导。在基因水平上我们将鉴定内源肽 配体和探针与先前识别的伤害性基因和伤害性敏化的遗传相互作用 信号通路。在我们的最终目标中，我们将探讨吗啡给药的细胞效应（钙变化） 以及是否已知吗啡的有害生物副作用、耐受性的发展和便秘 在我们的新模型中也观察到了这一点。成功完成这些目标将提供全面的蜂窝 以及这个新模型中镇痛信号的遗传分析 - 可能生成可测试的基本信息 脊椎动物模型中正在进行的工作的假设。展望未来，这种新的镇痛信号模型将 提供了公正的基因发现方法的可能性，这些方法应该允许识别新的基因 镇痛所需的保守基因——在某些情况下可能与人类和人类相关的目标 健康，值得在脊椎动物模型和临床环境中进一步探索。