Purification of family B G protein-coupled receptors using nanodiscs: Application to human glucagon-like peptide-1 receptor

• Published in: PloS one Vol. 12; no. 6; p. e0179568
• Main Authors: Cai, Yingying, Liu, Yuting, Culhane, Kelly J, DeVree, Brian T, Yang, Yang, Sunahara, Roger K, Yan, Elsa C Y
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 13.06.2017; Public Library of Science (PLoS)
• Subjects: Activation analysis; Amino acids; Analysis; Apolipoproteins; Biochemistry; Biocompatibility; Biology and Life Sciences; Biomedical materials; Biophysics; Chemistry; Chromatography; Coupling (molecular); Denaturation; Density; Diabetes; Diabetes mellitus; Diabetes Mellitus, Type 2 - drug therapy; Diseases; Engineering and Technology; Environment; Exenatide; Functional anatomy; G protein-coupled receptors; G proteins; Glucagon; Glucagon-like peptide 1; Glucagon-Like Peptide 1 - metabolism; Glucagon-Like Peptide-1 Receptor - agonists; Glucagon-Like Peptide-1 Receptor - genetics; Glucagon-Like Peptide-1 Receptor - isolation & purification; Guanine nucleotide-binding protein; HEK293 Cells; Homeostasis; Humans; Hypoglycemic Agents - therapeutic use; Kinases; Labeling; Ligands; Lipid bilayers; Lipid Bilayers - chemistry; Lipid Bilayers - metabolism; Lipids; Lipoproteins, HDL - chemistry; Lipoproteins, HDL - metabolism; Metabolic disorders; Metabolism; Methods; Microscopy, Electron, Transmission; Mutagenesis; Nanostructure; Nanostructures - chemistry; Nanostructures - ultrastructure; Nanotechnology - methods; Osteoporosis; Particulates; Peptides; Peptides - metabolism; Peptides - therapeutic use; Physical Sciences; Protein Binding; Protein denaturation; Protein purification; Proteins; Purification; Receptors; Receptors, G-Protein-Coupled - agonists; Receptors, G-Protein-Coupled - genetics; Receptors, G-Protein-Coupled - isolation & purification; Reproducibility of Results; Rodents; Signal transduction; Solubilization; Spectroscopic analysis; Stabilization; Studies; Venoms - metabolism; Venoms - therapeutic use; United States > US; Connecticut; California
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0179568

Family B G protein-coupled receptors (GPCRs) play vital roles in hormone-regulated homeostasis. They are drug targets for metabolic diseases, including type 2 diabetes and osteoporosis. Despite their importance, the signaling mechanisms for family B GPCRs at the molecular level remain largely unexplored due to the challenges in purification of functional receptors in sufficient amount for biophysical characterization. Here, we purified the family B GPCR human glucagon-like peptide-1 (GLP-1) receptor (GLP1R), whose agonists, e.g. exendin-4, are used for the treatment of type 2 diabetes mellitus. The receptor was expressed in HEK293S GnTl- cells using our recently developed protocol. The protocol incorporates the receptor into the native-like lipid environment of reconstituted high density lipoprotein (rHDL) particles, also known as nanodiscs, immediately after the membrane solubilization step followed by chromatographic purification, minimizing detergent contact with the target receptor to reduce denaturation and prolonging stabilization of receptor in lipid bilayers without extra steps of reconstitution. This method yielded purified GLP1R in nanodiscs that could bind to GLP-1 and exendin-4 and activate Gs protein. This nanodisc purification method can potentially be a general strategy to routinely obtain purified family B GPCRs in the 10s of microgram amounts useful for spectroscopic analysis of receptor functions and activation mechanisms.