Hallucinogens and 5-HT Receptors: Mechanisms and Effects

描述（由申请人提供）：致幻剂的作用呈现出一幅复杂的画面，因为它们(a)引起的反应不同于其他激动剂对特定靶点的反应，如5- ht2受体亚型（5- ht2a, 5- HT2C）；(b)调节特定神经元的多种信号通路；(c)涉及到几个大脑区域的行为影响。在这个项目的前期，我们开发了一种多尺度的方法来解决这个复杂的问题，将分子和细胞信号事件的见解与参与行为产生的神经元和大脑区域的更大规模过程联系起来。我们还开发了强大的遗传动物模型和蛋白质工程结构，可用于探索这种专门设计的结构在体外和体内的后果。本次PPG更新申请的研究计划基于三个项目的跨学科迭代研究协议，提出了这样一个多尺度的调查。协调和整合的研究跨越了规模和组织的尺度：从项目1中研究的野生型和突变型gpcr激活形式的分子结构及其在信号通路中的相互作用；以定量基因组学为基础的转录组指纹识别方法，反映了通过这些受体的差异信号反应，以及在细胞信号水平上识别与致幻剂特异性反应有关的神经元和特定分子机制，这是项目2中所追求的；在项目3中，对5-HT2AR及其与其他受体和信号介质的相互作用进行脑区特异性操作的转基因小鼠进行研究。项目1中基于生物信息学、结构分析和模拟的受体及其信号相关蛋白的新结构将在项目2中表达，以(i)研究致幻剂信号特异性的细胞机制；（ii）测试关于受体二聚化和与项目1中生成的支架蛋白相互作用的机制假设；（iii）在项目#3中选择机制上最具揭示性的敲入/敲除和区域特异性恢复和删除实验，以阐明与支持或破坏特定机制相关的行为表型。通过其整合的结构和重点，该研究计划有望继续对理解药物滥用以及设计新的基于gpcr的药物成瘾疗法具有重要意义。

DESCRIPTION (provided by applicant): Hallucinogen actions present a complicated picture because they (a) cause responses that differ from those of other agonists on specific targets such as 5-HT2 receptor subtypes (5-HT2A, 5- HT2C); (b) modulate multiple signaling pathways in specific neurons; and (c) involve several brain regions in their behavioral effects. In the previous period of this Program Project we have developed a multi-scale approach to this complex problem that connects insights about molecular and cellular signaling events to larger scale processes in the neurons and brain regions involved in the generation of the behaviors. We have also developed the powerful genetic animal models and the protein engineering constructs that can be used to probe the consequences of such specifically designed constructs in vitro and in vivo. The research plan of this PPG renewal application presents such a multi-scale investigation, based on an interdisciplinary protocol of iterative studies in the three Projects. The coordinated and integrated studies span scales of size and organization: from molecular structures of activated forms of the wild type and mutant GPCRs and their interactions in the signaling pathways, that are studied in Project 1; to the quantitative genomics-based approach termed Transcriptome Fingerprinting that reflects differential signaling responses through these receptors, and the identification of neurons and specific molecular mechanisms at the cell signaling level that are involved in hallucinogen-specific responses, pursued in Project 2; and onward to genetically modified mice with brain-region-specific manipulations of the 5-HT2AR and its interactions with other receptors and signaling mediators, in Project 3. New constructs of the receptors and their signaling-associated proteins, engineered in Project 1 from bioinformatics, structure-based analysis and simulations, will be expressed in Project 2 to (i) study of the cellular mechanisms underlying hallucinogen signaling specificity; (ii) test mechanistic hypotheses about receptor dimerization and interactions with scaffolding proteins generated in Project 1; and (iii) select the mechanistically most revealing ones for knock-in/knock-out and region-specific restoration and deletion experiments in Project #3, in order to elucidate the behavioral phenotypes associated with support or disruption of specific mechanisms. Through its integrative construct and focus, this research plan is expected to continue to have significant implications for understanding drug abuse in general, as well as on the design of new GPCR-based therapeutics for drug addiction. PROGRAM CHARACTERISTICS