« Previous AbstractEffects of reduced rainfall on coffee quality and volatile composition    Next AbstractMonitoring of volatile compound emissions during dry anaerobic digestion of the Organic Fraction of Municipal Solid Waste by Proton Transfer Reaction Time-of-Flight Mass Spectrometry »

J Phys Chem B

Title:		In-Cell Detection of Conformational Substates of a G Protein-Coupled Receptor Quaternary Structure: Modulation of Substate Probability by Cognate Ligand Binding
Author(s):		Paprocki J; Biener G; Stoneman M; Raicu V;
Address:		"Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States. Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States"
Journal Title:		J Phys Chem B
Year:		2020
Volume:		20201029
Issue:		45
Page Number:		10062 - 10076
DOI:		10.1021/acs.jpcb.0c06081
ISSN/ISBN:		1520-5207 (Electronic) 1520-5207 (Linking)
Abstract:		"While the notion that G protein-coupled receptors (GPCRs) associate into homo- and hetero-oligomers has gained more recognition in recent years, a lack of consensus remains among researchers regarding the functional relevance of GPCR oligomerization. A technique, Forster resonance energy transfer (FRET) spectrometry, allows for the determination of the oligomeric (or quaternary) structure of proteins in living cells via analysis of efficiency distributions of energy transferred from optically excited fluorescent tags acting as donors of energy to fluorescent tags acting as acceptors of energy and residing within the same oligomer. In this study, we significantly improved the resolution of FRET spectrometry to detect subtle differences in quaternary structures of GPCR oligomers within living cells. We then used this approach to study the conformational substates of oligomers of the sterile 2 alpha-factor receptor (Ste2), a class D GPCR found in the yeast Saccharomyces cerevisiae of mating type a. Ste2 has previously been shown to form tetramers at relatively low expression levels (11 to 140 molecules/mum(2)) in the absence of its cognate ligand, the alpha-factor pheromone. The significantly improved FRET spectrometry technique allowed us to detect multiple distinct quaternary conformational substates of Ste2 oligomers, and to assess how the alpha-factor ligand altered the proportion of such substates. The ability to determine quaternary structure substates of GPCRs provides exquisite means to elucidate functional relevance of GPCR oligomerization"
Keywords:		"*Fluorescence Resonance Energy Transfer GTP-Binding Proteins Ligands Probability *Receptors, G-Protein-Coupled/metabolism Receptors, Mating Factor/genetics/metabolism;"
Notes:		"MedlinePaprocki, Joel Biener, Gabriel Stoneman, Michael Raicu, Valerica eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 2020/10/30 J Phys Chem B. 2020 Nov 12; 124(45):10062-10076. doi: 10.1021/acs.jpcb.0c06081. Epub 2020 Oct 29"