Center for the Neurobiology of Addiction, Pain and Emotion (D.J.M., M.R.B.), Department of Anesthesiology and Pain Medicine (D.J.M., M.R.B.), Department of Pharmacology (M.R.B.), and Department of Bioengineering (M.R.B.), University of Washington, Seattle, Washington
Pharmacol Rev. 2023 Nov;75(6):1119-1139. doi: 10.1124/pharmrev.122.000584. Epub 2023 Jul 10.
Despite the fact that roughly 40% of all US Food and Drug Administration (FDA)-approved pharmacological therapeutics target G protein-coupled receptors (GPCRs), there remains a gap in our understanding of the physiologic and functional role of these receptors at the systems level. Although heterologous expression systems and in vitro assays have revealed a tremendous amount about GPCR signaling cascades, how these cascades interact across cell types, tissues, and organ systems remains obscure. Classic behavioral pharmacology experiments lack both the temporal and spatial resolution to resolve these long-standing issues. Over the past half century, there has been a concerted effort toward the development of optical tools for understanding GPCR signaling. From initial ligand uncaging approaches to more recent development of optogenetic techniques, these strategies have allowed researchers to probe longstanding questions in GPCR pharmacology both in vivo and in vitro. These tools have been employed across biologic systems and have allowed for interrogation of everything from specific intramolecular events to pharmacology at the systems level in a spatiotemporally specific manner. In this review, we present a historical perspective on the motivation behind and development of a variety of optical toolkits that have been generated to probe GPCR signaling. Here we highlight how these tools have been used in vivo to uncover the functional role of distinct populations of GPCRs and their signaling cascades at a systems level. SIGNIFICANCE STATEMENT: G protein-coupled receptors (GPCRs) remain one of the most targeted classes of proteins for pharmaceutical intervention, yet we still have a limited understanding of how their unique signaling cascades effect physiology and behavior at the systems level. In this review, we discuss a vast array of optical techniques that have been devised to probe GPCR signaling both in vitro and in vivo.
尽管大约 40%的美国食品和药物管理局 (FDA) 批准的药理学治疗药物针对 G 蛋白偶联受体 (GPCR)，但我们仍然缺乏对这些受体在系统水平上的生理和功能作用的理解。尽管异源表达系统和体外测定揭示了大量关于 GPCR 信号级联的信息，但这些级联如何在细胞类型、组织和器官系统之间相互作用仍然不清楚。经典的行为药理学实验缺乏解决这些长期存在的问题的时间和空间分辨率。在过去的半个世纪里，人们一直在努力开发用于了解 GPCR 信号的光学工具。从最初的配体光解方法到最近的光遗传学技术的发展，这些策略使研究人员能够在体内和体外研究 GPCR 药理学中的长期问题。这些工具已经在生物系统中得到了应用，并允许以时空特异性的方式研究从特定的分子内事件到系统水平药理学的一切。在这篇综述中，我们介绍了一系列光学工具包的发展背景和动机，这些工具包被开发出来用于探测 GPCR 信号。在这里，我们强调了这些工具如何在体内被用于揭示不同群体的 GPCR 及其信号级联在系统水平上的功能作用。
