Heterotrimeric G Protein Subunit Gαq Is a Master Switch for Gβγ-Mediated Calcium Mobilization by Gi-Coupled GPCRs

Eva Marie Pfeil; Julian Brands; Nicole Merten; Timo Vögtle; Maddalena Vescovo; Ulrike Rick; Ina-Maria Albrecht; Nina Heycke; Kouki Kawakami; Yuki Ono; Francois Marie Ngako Kadji; Suzune Hiratsuka; Junken Aoki; Felix Häberlein; Michaela Matthey; Jaspal Garg; Stephanie Hennen; Marie-Lise Jobin; Kerstin Seier; Davide Calebiro; Alexander Pfeifer; Akos Heinemann; Daniela Wenzel; Gabriele M König; Bernhard Nieswandt; Bernd K Fleischmann; Asuka Inoue; Katharina Simon; Evi Kostenis

doi:10.1016/j.molcel.2020.10.027

Heterotrimeric G Protein Subunit Gαq Is a Master Switch for Gβγ-Mediated Calcium Mobilization by Gi-Coupled GPCRs

Mol Cell. 2020 Dec 17;80(6):940-954.e6. doi: 10.1016/j.molcel.2020.10.027. Epub 2020 Nov 16.

Authors

Eva Marie Pfeil¹, Julian Brands¹, Nicole Merten², Timo Vögtle³, Maddalena Vescovo², Ulrike Rick², Ina-Maria Albrecht², Nina Heycke², Kouki Kawakami⁴, Yuki Ono⁴, Francois Marie Ngako Kadji⁴, Suzune Hiratsuka⁴, Junken Aoki⁴, Felix Häberlein¹, Michaela Matthey⁵, Jaspal Garg⁶, Stephanie Hennen², Marie-Lise Jobin⁷, Kerstin Seier⁷, Davide Calebiro⁸, Alexander Pfeifer⁹, Akos Heinemann¹⁰, Daniela Wenzel⁵, Gabriele M König¹¹, Bernhard Nieswandt³, Bernd K Fleischmann⁹, Asuka Inoue⁴, Katharina Simon¹², Evi Kostenis¹³

Affiliations

¹ Molecular, Cellular and Pharmacobiology Section, Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany; Research Training Group 1873, University of Bonn, Bonn, Germany.
² Molecular, Cellular and Pharmacobiology Section, Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany.
³ Institute of Experimental Biomedicine I, University Hospital Würzburg and Rudolf Virchow Center, University of Würzburg, 97080 Würzburg, Germany.
⁴ Graduate School of Pharmaceutical Science, Tohoku University, Sendai 980-8578, Japan.
⁵ Department of Systems Physiology, Medical Faculty, Ruhr University Bochum, 44801 Bochum, Germany; Institute of Physiology I, Life and Brain Center, Medical Faculty, University of Bonn, Venusberg-Campus 1, 53127 Bonn, Germany.
⁶ Institute of Pharmacology and Toxicology, University Hospital Bonn, University of Bonn, 53127 Bonn, Germany.
⁷ Institute of Pharmacology and Toxicology and Bio-Imaging Center, University of Würzburg, 97078 Würzburg, Germany.
⁸ Institute of Pharmacology and Toxicology and Bio-Imaging Center, University of Würzburg, 97078 Würzburg, Germany; Institute of Metabolism and Systems Research and Centre of Membrane Proteins and Receptors, University of Birmingham, B15 2TT Birmingham, UK.
⁹ Institute of Physiology I, Life and Brain Center, Medical Faculty, University of Bonn, Venusberg-Campus 1, 53127 Bonn, Germany.
¹⁰ Division of Pharmacology, Otto-Loewi Research Center for Vascular Biology, Immunology and Inflammation, Medical University of Graz, 8010 Graz, Austria.
¹¹ Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany.
¹² Molecular, Cellular and Pharmacobiology Section, Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany. Electronic address: [email protected].
¹³ Molecular, Cellular and Pharmacobiology Section, Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany. Electronic address: [email protected].

PMID: 33202251
DOI: 10.1016/j.molcel.2020.10.027

Abstract

Mechanisms that control mobilization of cytosolic calcium [Ca²⁺]_i are key for regulation of numerous eukaryotic cell functions. One such paradigmatic mechanism involves activation of phospholipase Cβ (PLCβ) enzymes by G protein βγ subunits from activated Gα_i-Gβγ heterotrimers. Here, we report identification of a master switch to enable this control for PLCβ enzymes in living cells. We find that the Gα_i-Gβγ-PLCβ-Ca²⁺ signaling module is entirely dependent on the presence of active Gα_q. If Gα_q is pharmacologically inhibited or genetically ablated, Gβγ can bind to PLCβ but does not elicit Ca²⁺ signals. Removal of an auto-inhibitory linker that occludes the active site of the enzyme is required and sufficient to empower "stand-alone control" of PLCβ by Gβγ. This dependence of Gi-Gβγ-Ca²⁺ on Gα_q places an entire signaling branch of G-protein-coupled receptors (GPCRs) under hierarchical control of Gq and changes our understanding of how Gi-GPCRs trigger [Ca²⁺]_i via PLCβ enzymes.

Keywords: Ca(2+) signaling; FR900359; GPCR; GPR17; Gi; Gq; PTX; heterotrimeric G protein; phospholipase Cβ; real-time BRET-based IP(3) biosensor.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Calcium / metabolism
Calcium Signaling / genetics
Cytosol / metabolism
GTP-Binding Protein alpha Subunits / genetics*
GTP-Binding Protein beta Subunits / genetics*
GTP-Binding Protein gamma Subunits / genetics*
HEK293 Cells
Heterotrimeric GTP-Binding Proteins / genetics*
Humans
Phospholipase C beta / genetics*
Protein Binding / genetics
Receptors, G-Protein-Coupled / genetics
Signal Transduction / genetics

Substances

G-protein Beta gamma
GTP-Binding Protein alpha Subunits
GTP-Binding Protein beta Subunits
GTP-Binding Protein gamma Subunits
Receptors, G-Protein-Coupled
Phospholipase C beta
Heterotrimeric GTP-Binding Proteins
Calcium

Grants and funding

212313/Z/18/Z/WT_/Wellcome Trust/United Kingdom