Ligand-directed labeling of opioid receptors for covalent attachment of fluorophores or small-molecule probes

Abstract

Summary: This protocol describes endogenous labeling of opioid receptors (ORs) using a ligand-directed reagent, naltrexamine-acylimidazole compounds (NAI-X). NAI acts by guiding and permanently tagging a small-molecule reporter (X)—such as fluorophores or biotin—to ORs. Here we detail syntheses and uses of NAI-X for OR visualization and functional studies. The NAI-X compounds overcome long-standing challenges in mapping and tracking endogenous ORs as the labeling can be done in situ with live tissues or cultured cells.For complete details on the use and execution of this protocol, please refer to Arttamangkul et al.1,2 : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

Keywords

• Cell Biology
• Cell culture
• Flow Cytometry/Mass Cytometry
• Microscopy
• Neuroscience
• Molecular/Chemical Probes