title: Allosteric regulation of G protein-coupled receptor activity by phospholipids.
abstract: Lipids are emerging as key regulators of membrane protein structure and activity. These effects can be attributed either to the modification of bilayer properties (thickness, curvature and surface tension) or to the binding of specific lipids to the protein surface. For G protein-coupled receptors (GPCRs), the effects of phospholipids on receptor structure and activity remain poorly understood. Here we reconstituted purified β2-adrenergic receptor (β2R) in high-density lipoparticles to systematically characterize the effect of biologically relevant phospholipids on receptor activity. We observed that the lipid headgroup type affected ligand binding (agonist and antagonist) and receptor activation. Specifically, phosphatidylgycerol markedly favored agonist binding and facilitated receptor activation, whereas phosphatidylethanolamine favored antagonist binding and stabilized the inactive state of the receptor. We then showed that these effects could be recapitulated with detergent-solubilized lipids, demonstrating that the functional modulation occurred in the absence of a bilayer. Our data suggest that phospholipids act as direct allosteric modulators of GPCR activity.
authors.affiliation: Laboratory for the Structure and Function of Biological Membranes, Center for Structural Biology and Bioinformatics, Université Libre de Bruxelles, Brussels, Belgium.
authors.forename: Rosie
authors.initials: R
authors.lastname: Dawaliby
authors.affiliation: Laboratory for the Structure and Function of Biological Membranes, Center for Structural Biology and Bioinformatics, Université Libre de Bruxelles, Brussels, Belgium.
authors.forename: Cataldo
authors.initials: C
authors.lastname: Trubbia
authors.affiliation: Laboratory of Pharmaceutical Chemistry Faculty of Pharmacy, Université Libre de Bruxelles, Brussels, Belgium.|Analytical Platform of the Faculty of Pharmacy, Faculty of Pharmacy, Université Libre de Bruxelles, Brussels, Belgium.
authors.forename: Cédric
authors.identifier: http://orcid.org/0000-0001-7453-7028
authors.initials: C
authors.lastname: Delporte
authors.affiliation: Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California, USA.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Masureel
authors.affiliation: Laboratory of Pharmaceutical Chemistry Faculty of Pharmacy, Université Libre de Bruxelles, Brussels, Belgium.|Analytical Platform of the Faculty of Pharmacy, Faculty of Pharmacy, Université Libre de Bruxelles, Brussels, Belgium.
authors.forename: Pierre
authors.initials: P
authors.lastname: Van Antwerpen
authors.affiliation: Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California, USA.
authors.forename: Brian K
authors.initials: BK
authors.lastname: Kobilka
authors.affiliation: Laboratory for the Structure and Function of Biological Membranes, Center for Structural Biology and Bioinformatics, Université Libre de Bruxelles, Brussels, Belgium.
authors.forename: Cédric
authors.initials: C
authors.lastname: Govaerts
mesh_terms: D058666:Adrenergic beta-2 Receptor Agonists / Q000378:metabolism; D058672:Adrenergic beta-2 Receptor Antagonists / Q000378:metabolism; D000494:Allosteric Regulation; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D006801:Humans; D008051:Lipid Bilayers; D010743:Phospholipids / Q000737:chemistry / Q000378:metabolism*; D018343:Receptors, Adrenergic, beta-2 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D043562:Receptors, G-Protein-Coupled / Q000737:chemistry / Q000378:metabolism; D013050:Spectrometry, Fluorescence; D018411:Spodoptera
chemical_list: D058666:Adrenergic beta-2 Receptor Agonists; D058672:Adrenergic beta-2 Receptor Antagonists; D008051:Lipid Bilayers; D010743:Phospholipids; D018343:Receptors, Adrenergic, beta-2; D043562:Receptors, G-Protein-Coupled