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Jang W, Senarath K, Feinberg G, Lu S, Lambert NA. Visualization of endogenous G proteins on endosomes and other organelles. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.05.583500. [PMID: 38496652 PMCID: PMC10942389 DOI: 10.1101/2024.03.05.583500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Classical G protein-coupled receptor (GPCR) signaling takes place in response to extracellular stimuli and involves receptors and heterotrimeric G proteins located at the plasma membrane. It has recently been established that GPCR signaling can also take place from intracellular membrane compartments, including endosomes that contain internalized receptors and ligands. While the mechanisms of GPCR endocytosis are well understood, it is not clear how well internalized receptors are supplied with G proteins. To address this gap we use gene editing, confocal microscopy, and bioluminescence resonance energy transfer to study the distribution and trafficking of endogenous G proteins. We show here that constitutive endocytosis is sufficient to supply newly internalized endocytic vesicles with 20-30% of the G protein density found at the plasma membrane. We find that G proteins are present on early, late, and recycling endosomes, are abundant on lysosomes, but are virtually undetectable on the endoplasmic reticulum, mitochondria, and the medial Golgi apparatus. Receptor activation does not change heterotrimer abundance on endosomes. Our findings provide a subcellular map of endogenous G protein distribution, suggest that G proteins may be partially excluded from nascent endocytic vesicles, and are likely to have implications for GPCR signaling from endosomes and other intracellular compartments.
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2
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Rysiewicz B, Błasiak E, Mystek P, Dziedzicka-Wasylewska M, Polit A. Beyond the G protein α subunit: investigating the functional impact of other components of the Gαi 3 heterotrimers. Cell Commun Signal 2023; 21:279. [PMID: 37817242 PMCID: PMC10566112 DOI: 10.1186/s12964-023-01307-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 09/05/2023] [Indexed: 10/12/2023] Open
Abstract
BACKGROUND Specific interactions between G protein-coupled receptors (GPCRs) and G proteins play a key role in mediating signaling events. While there is little doubt regarding receptor preference for Gα subunits, the preferences for specific Gβ and Gγ subunits and the effects of different Gβγ dimer compositions on GPCR signaling are poorly understood. In this study, we aimed to investigate the subcellular localization and functional response of Gαi3-based heterotrimers with different combinations of Gβ and Gγ subunits. METHODS Live-cell imaging microscopy and colocalization analysis were used to investigate the subcellular localization of Gαi3 in combination with Gβ1 or Gβ2 heterotrimers, along with representative Gγ subunits. Furthermore, fluorescence lifetime imaging microscopy (FLIM-FRET) was used to investigate the nanoscale distribution of Gαi3-based heterotrimers in the plasma membrane, specifically with the dopamine D2 receptor (D2R). In addition, the functional response of the system was assessed by monitoring intracellular cAMP levels and conducting bioinformatics analysis to further characterize the heterotrimer complexes. RESULTS Our results show that Gαi3 heterotrimers mainly localize to the plasma membrane, although the degree of colocalization is influenced by the accompanying Gβ and Gγ subunits. Heterotrimers containing Gβ2 showed slightly lower membrane localization compared to those containing Gβ1, but certain combinations, such as Gαi3β2γ8 and Gαi3β2γ10, deviated from this trend. Examination of the spatial arrangement of Gαi3 in relation to D2R and of changes in intracellular cAMP level showed that the strongest functional response is observed for those trimers for which the distance between the receptor and the Gα subunit is smallest, i.e. complexes containing Gβ1 and Gγ8 or Gγ10 subunit. Deprivation of Gαi3 lipid modifications resulted in a significant decrease in the amount of protein present in the cell membrane, but did not always affect intracellular cAMP levels. CONCLUSION Our studies show that the composition of G protein heterotrimers has a significant impact on the strength and specificity of GPCR-mediated signaling. Different heterotrimers may exhibit different conformations, which further affects the interactions of heterotrimers and GPCRs, as well as their interactions with membrane lipids. This study contributes to the understanding of the complex signaling mechanisms underlying GPCR-G-protein interactions and highlights the importance of the diversity of Gβ and Gγ subunits in G-protein signaling pathways. Video Abstract.
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Affiliation(s)
- Beata Rysiewicz
- Department of Physical Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Ewa Błasiak
- Department of Physical Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Paweł Mystek
- Department of Physical Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Marta Dziedzicka-Wasylewska
- Department of Physical Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Agnieszka Polit
- Department of Physical Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland.
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3
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Klenk C, Scrivens M, Niederer A, Shi S, Mueller L, Gersz E, Zauderer M, Smith ES, Strohner R, Plückthun A. A Vaccinia-based system for directed evolution of GPCRs in mammalian cells. Nat Commun 2023; 14:1770. [PMID: 36997531 PMCID: PMC10063554 DOI: 10.1038/s41467-023-37191-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 03/06/2023] [Indexed: 04/03/2023] Open
Abstract
Directed evolution in bacterial or yeast display systems has been successfully used to improve stability and expression of G protein-coupled receptors for structural and biophysical studies. Yet, several receptors cannot be tackled in microbial systems due to their complex molecular composition or unfavorable ligand properties. Here, we report an approach to evolve G protein-coupled receptors in mammalian cells. To achieve clonality and uniform expression, we develop a viral transduction system based on Vaccinia virus. By rational design of synthetic DNA libraries, we first evolve neurotensin receptor 1 for high stability and expression. Second, we demonstrate that receptors with complex molecular architectures and large ligands, such as the parathyroid hormone 1 receptor, can be readily evolved. Importantly, functional receptor properties can now be evolved in the presence of the mammalian signaling environment, resulting in receptor variants exhibiting increased allosteric coupling between the ligand binding site and the G protein interface. Our approach thus provides insights into the intricate molecular interplay required for GPCR activation.
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Affiliation(s)
- Christoph Klenk
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland.
| | - Maria Scrivens
- Vaccinex, Inc., 1895 Mt. Hope Avenue, Rochester, New York, 14620, NY, USA
| | - Anina Niederer
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Shuying Shi
- Vaccinex, Inc., 1895 Mt. Hope Avenue, Rochester, New York, 14620, NY, USA
| | - Loretta Mueller
- Vaccinex, Inc., 1895 Mt. Hope Avenue, Rochester, New York, 14620, NY, USA
| | - Elaine Gersz
- Vaccinex, Inc., 1895 Mt. Hope Avenue, Rochester, New York, 14620, NY, USA
| | - Maurice Zauderer
- Vaccinex, Inc., 1895 Mt. Hope Avenue, Rochester, New York, 14620, NY, USA
| | - Ernest S Smith
- Vaccinex, Inc., 1895 Mt. Hope Avenue, Rochester, New York, 14620, NY, USA
| | - Ralf Strohner
- MorphoSys AG, Semmelweisstr. 7, 82152, Planegg, Germany
| | - Andreas Plückthun
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland.
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4
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Huang SK, Picard LP, Rahmatullah RSM, Pandey A, Van Eps N, Sunahara RK, Ernst OP, Sljoka A, Prosser RS. Mapping the conformational landscape of the stimulatory heterotrimeric G protein. Nat Struct Mol Biol 2023; 30:502-511. [PMID: 36997760 DOI: 10.1038/s41594-023-00957-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 02/24/2023] [Indexed: 04/01/2023]
Abstract
Heterotrimeric G proteins serve as membrane-associated signaling hubs, in concert with their cognate G-protein-coupled receptors. Fluorine nuclear magnetic resonance spectroscopy was employed to monitor the conformational equilibria of the human stimulatory G-protein α subunit (Gsα) alone, in the intact Gsαβ1γ2 heterotrimer or in complex with membrane-embedded human adenosine A2A receptor (A2AR). The results reveal a concerted equilibrium that is strongly affected by nucleotide and interactions with the βγ subunit, the lipid bilayer and A2AR. The α1 helix of Gsα exhibits significant intermediate timescale dynamics. The α4β6 loop and α5 helix undergo membrane/receptor interactions and order-disorder transitions respectively, associated with G-protein activation. The αN helix adopts a key functional state that serves as an allosteric conduit between the βγ subunit and receptor, while a significant fraction of the ensemble remains tethered to the membrane and receptor upon activation.
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Affiliation(s)
- Shuya Kate Huang
- Department of Chemistry, University of Toronto, UTM, Mississauga, Ontario, Canada
| | | | - Rima S M Rahmatullah
- Department of Chemistry, University of Toronto, UTM, Mississauga, Ontario, Canada
| | - Aditya Pandey
- Department of Chemistry, University of Toronto, UTM, Mississauga, Ontario, Canada
| | - Ned Van Eps
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Roger K Sunahara
- Department of Pharmacology, University of California San Diego School of Medicine, La Jolla, CA, USA
| | - Oliver P Ernst
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Adnan Sljoka
- RIKEN Center for Advanced Intelligence Project, RIKEN, Tokyo, Japan.
| | - R Scott Prosser
- Department of Chemistry, University of Toronto, UTM, Mississauga, Ontario, Canada.
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada.
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5
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Dmitrieva DA, Kotova TV, Safronova NA, Sadova AA, Dashevskii DE, Mishin AV. Protein Design Strategies for the Structural–Functional Studies of G Protein-Coupled Receptors. BIOCHEMISTRY (MOSCOW) 2023; 88:S192-S226. [PMID: 37069121 DOI: 10.1134/s0006297923140110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
G protein-coupled receptors (GPCRs) are an important family of membrane proteins responsible for many physiological functions in human body. High resolution GPCR structures are required to understand their molecular mechanisms and perform rational drug design, as GPCRs play a crucial role in a variety of diseases. That is difficult to obtain for the wild-type proteins because of their low stability. In this review, we discuss how this problem can be solved by using protein design strategies developed to obtain homogeneous stabilized GPCR samples for crystallization and cryoelectron microscopy.
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Affiliation(s)
- Daria A Dmitrieva
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia
| | - Tatiana V Kotova
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia
| | - Nadezda A Safronova
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia
| | - Alexandra A Sadova
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia
| | - Dmitrii E Dashevskii
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia
| | - Alexey V Mishin
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia.
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6
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Kolesnikov AV, Lobysheva E, Gnana-Prakasam JP, Kefalov VJ, Kisselev OG. Regulation of rod photoreceptor function by farnesylated G-protein γ-subunits. PLoS One 2022; 17:e0272506. [PMID: 35939447 PMCID: PMC9359561 DOI: 10.1371/journal.pone.0272506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 07/20/2022] [Indexed: 11/19/2022] Open
Abstract
Heterotrimeric G-protein transducin, Gt, is a key signal transducer and amplifier in retinal rod and cone photoreceptor cells. Despite similar subunit composition, close amino acid identity, and identical posttranslational farnesylation of their Gγ subunits, rods and cones rely on unique Gγ1 (Gngt1) and Gγc (Gngt2) isoforms, respectively. The only other farnesylated G-protein γ-subunit, Gγ11 (Gng11), is expressed in multiple tissues but not retina. To determine whether Gγ1 regulates uniquely rod phototransduction, we generated transgenic rods expressing Gγ1, Gγc, or Gγ11 in Gγ1-deficient mice and analyzed their properties. Immunohistochemistry and Western blotting demonstrated the robust expression of each transgenic Gγ in rod cells and restoration of Gαt1 expression, which is greatly reduced in Gγ1-deficient rods. Electroretinography showed restoration of visual function in all three transgenic Gγ1-deficient lines. Recordings from individual transgenic rods showed that photosensitivity impaired in Gγ1-deficient rods was also fully restored. In all dark-adapted transgenic lines, Gαt1 was targeted to the outer segments, reversing its diffuse localization found in Gγ1-deficient rods. Bright illumination triggered Gαt1 translocation from the rod outer to inner segments in all three transgenic strains. However, Gαt1 translocation in Gγ11 transgenic mice occurred at significantly dimmer background light. Consistent with this, transretinal ERG recordings revealed gradual response recovery in moderate background illumination in Gγ11 transgenic mice but not in Gγ1 controls. Thus, while farnesylated Gγ subunits are functionally active and largely interchangeable in supporting rod phototransduction, replacement of retina-specific Gγ isoforms by the ubiquitous Gγ11 affects the ability of rods to adapt to background light.
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Affiliation(s)
- Alexander V. Kolesnikov
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, CA, United States of America
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Elena Lobysheva
- Department of Ophthalmology, Saint Louis University School of Medicine, Saint Louis, Missouri, United States of America
| | - Jaya P. Gnana-Prakasam
- Department of Ophthalmology, Saint Louis University School of Medicine, Saint Louis, Missouri, United States of America
- Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, Saint Louis, Missouri, United States of America
| | - Vladimir J. Kefalov
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, CA, United States of America
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Physiology and Biophysics, University of California, Irvine, CA, United States of America
| | - Oleg G. Kisselev
- Department of Ophthalmology, Saint Louis University School of Medicine, Saint Louis, Missouri, United States of America
- Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, Saint Louis, Missouri, United States of America
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7
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Kolb P, Kenakin T, Alexander SPH, Bermudez M, Bohn LM, Breinholt CS, Bouvier M, Hill SJ, Kostenis E, Martemyanov K, Neubig RR, Onaran HO, Rajagopal S, Roth BL, Selent J, Shukla AK, Sommer ME, Gloriam DE. Community Guidelines for GPCR Ligand Bias: IUPHAR Review XX. Br J Pharmacol 2022; 179:3651-3674. [PMID: 35106752 PMCID: PMC7612872 DOI: 10.1111/bph.15811] [Citation(s) in RCA: 83] [Impact Index Per Article: 41.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 01/11/2022] [Accepted: 01/13/2022] [Indexed: 11/29/2022] Open
Abstract
G protein-coupled receptors modulate a plethora of physiological processes and mediate the effects of one-third of FDA-approved drugs. Depending on which ligand activates a receptor, it can engage different intracellular transducers. This 'biased signaling' paradigm requires that we now characterize physiological signaling not just by receptors but by ligand-receptor pairs. Ligands eliciting biased signaling may constitute better drugs with higher efficacy and fewer adverse effects. However, ligand bias is very complex, making reproducibility and description challenging. Here, we provide guidelines and terminology for any scientists to design and report ligand bias experiments. The guidelines will aid consistency and clarity, as the basic receptor research and drug discovery communities continue to advance our understanding and exploitation of ligand bias. Scientific insight, biosensors, and analytical methods are still evolving and should benefit from and contribute to the implementation of the guidelines, together improving translation from in vitro to disease-relevant in vivo models.
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Affiliation(s)
- Peter Kolb
- Department of Pharmaceutical Chemistry, Philipps-University Marburg, Marburg, Germany
| | - Terry Kenakin
- Department of Pharmacology, University of North Carolina School of Medicine, North, Carolina, USA
| | | | - Marcel Bermudez
- Department of Pharmaceutical and Medicinal Chemistry, University of Münster, Münster, Germany
| | - Laura M Bohn
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, USA
| | - Christian S Breinholt
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Michel Bouvier
- Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Québec, Canada
| | - Stephen J Hill
- School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Evi Kostenis
- Molecular, Cellular, and Pharmacobiology Section, Institute for Pharmaceutical Biology, University of Bonn, Bonn, Germany
| | - Kirill Martemyanov
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, USA
| | - Rick R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - H Ongun Onaran
- Molecular Biology and Technology Development Unit, Department of Pharmacology, Faculty of Medicine, Ankara University, Ankara, Turkey
| | - Sudarshan Rajagopal
- Department of Medicine, Duke University Medical Center, Durham, NC, USA.,Department of Biochemistry, Duke University Medical Center, Durham, NC, USA
| | - Bryan L Roth
- Department of Pharmacology, University of North Carolina School of Medicine, North, Carolina, USA
| | - Jana Selent
- Research Programme on Biomedical Informatics, Hospital Del Mar Medical Research Institute, Department of Experimental and Health Sciences, Pompeu Fabra University, Barcelona, Spain
| | - Arun K Shukla
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India
| | - Martha E Sommer
- Institute of Medical Physics and Biophysics, Charité-Universitätsmedizin Berlin, Berlin, Germany.,Current affiliation: ISAR Bioscience Institute, Munich-Planegg, Germany
| | - David E Gloriam
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
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8
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Tennakoon M, Senarath K, Kankanamge D, Ratnayake K, Wijayaratna D, Olupothage K, Ubeysinghe S, Martins-Cannavino K, Hébert TE, Karunarathne A. Subtype-dependent regulation of Gβγ signalling. Cell Signal 2021; 82:109947. [PMID: 33582184 PMCID: PMC8026654 DOI: 10.1016/j.cellsig.2021.109947] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 02/01/2021] [Accepted: 02/02/2021] [Indexed: 01/04/2023]
Abstract
G protein-coupled receptors (GPCRs) transmit information to the cell interior by transducing external signals to heterotrimeric G protein subunits, Gα and Gβγ subunits, localized on the inner leaflet of the plasma membrane. Though the initial focus was mainly on Gα-mediated events, Gβγ subunits were later identified as major contributors to GPCR-G protein signalling. A broad functional array of Gβγ signalling has recently been attributed to Gβ and Gγ subtype diversity, comprising 5 Gβ and 12 Gγ subtypes, respectively. In addition to displaying selectivity towards each other to form the Gβγ dimer, numerous studies have identified preferences of distinct Gβγ combinations for specific GPCRs, Gα subtypes and effector molecules. Importantly, Gβ and Gγ subtype-dependent regulation of downstream effectors, representing a diverse range of signalling pathways and physiological functions have been found. Here, we review the literature on the repercussions of Gβ and Gγ subtype diversity on direct and indirect regulation of GPCR/G protein signalling events and their physiological outcomes. Our discussion additionally provides perspective in understanding the intricacies underlying molecular regulation of subtype-specific roles of Gβγ signalling and associated diseases.
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Affiliation(s)
- Mithila Tennakoon
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA
| | - Kanishka Senarath
- Genetics and Molecular Biology Unit, University of Sri Jayewardenepura, Nugegoda, Sri Lanka
| | - Dinesh Kankanamge
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA
| | - Kasun Ratnayake
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA; Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Dhanushan Wijayaratna
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA
| | - Koshala Olupothage
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA
| | - Sithurandi Ubeysinghe
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA
| | | | - Terence E Hébert
- Department of Pharmacology and Therapeutics, McGill University, Montréal, QC H3G 1Y6, Canada.
| | - Ajith Karunarathne
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA.
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9
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Taleb SJ, Wei J, Mialki RK, Dong S, Li Y, Zhao J, Zhao Y. A blocking peptide stabilizes lysophosphatidic acid receptor 1 and promotes lysophosphatidic acid-induced cellular responses. J Cell Biochem 2021; 122:827-834. [PMID: 33847006 DOI: 10.1002/jcb.29919] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 02/09/2021] [Accepted: 02/18/2021] [Indexed: 11/06/2022]
Abstract
G protein-coupled receptors regulate a variety of cellular responses and have been considered as therapeutic targets for human diseases. Lysophosphatidic acid receptor 1 (LPA1) is a receptor for bioactive lysophospholipid, LPA. LPA/LPA1-mediated signaling contributes to inflammatory and fibrotic responses in lung diseases; thus understanding regulation of LPA1 stability is important for modulating LPA/LPA1 signaling. Our previous study has shown that LPA1 is degraded in the Nedd4 like (Nedd4L) E3 ubiquitin ligase-mediated ubiquitin-proteasome system. In the current study, we attempt to identify a peptide that stabilizes LPA1 through disrupting LPA1 association with Nedd4L. LPA treatment induces both endogenous and overexpressed LPA1 degradation, which is attenuated by a proteasome inhibitor, suggesting that LPA1 is degraded in the proteasome. LPA increases phosphorylation of extracellular signal-regulated kinase 1/2 (Erk1/2) and I-κB kinase in lung epithelial cells, and this effect is promoted by overexpression of a peptide (P1) that mimics C-terminal of LPA1. P1, not a control peptide, attenuates LPA-induced LPA1 ubiquitination and degradation, suggesting that P1 stabilizes LPA1. Further, P1 diminishes Nedd4L-mediated degradation of LPA1 and Nedd4L/LPA1 association. In addition to increasing LPA1 signaling, P1 enhances LPA-induced cell migration and gene expression of Elafin, matrix metallopeptidase 1, and serpin family B member 2 in lung epithelial cells. These data suggest that disruption of LPA1 interaction with Nedd4L by P1 increases LPA1 stability and LPA/LPA1 signaling.
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Affiliation(s)
- Sarah J Taleb
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, Ohio, USA
| | - Jianxin Wei
- Department of Medicine, The University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Rachel K Mialki
- Department of Medicine, The University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Su Dong
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, Ohio, USA
| | - Yanhui Li
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, Ohio, USA
| | - Jing Zhao
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, Ohio, USA.,Pulmonary, Critical Care and Sleep Medicine Division, The Ohio State University, Columbus, Ohio, USA
| | - Yutong Zhao
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, Ohio, USA.,Pulmonary, Critical Care and Sleep Medicine Division, The Ohio State University, Columbus, Ohio, USA
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10
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Polit A, Mystek P, Błasiak E. Every Detail Matters. That Is, How the Interaction between Gα Proteins and Membrane Affects Their Function. MEMBRANES 2021; 11:222. [PMID: 33804791 PMCID: PMC8003949 DOI: 10.3390/membranes11030222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 03/17/2021] [Accepted: 03/18/2021] [Indexed: 11/16/2022]
Abstract
In highly organized multicellular organisms such as humans, the functions of an individual cell are dependent on signal transduction through G protein-coupled receptors (GPCRs) and subsequently heterotrimeric G proteins. As most of the elements belonging to the signal transduction system are bound to lipid membranes, researchers are showing increasing interest in studying the accompanying protein-lipid interactions, which have been demonstrated to not only provide the environment but also regulate proper and efficient signal transduction. The mode of interaction between the cell membrane and G proteins is well known. Despite this, the recognition mechanisms at the molecular level and how the individual G protein-membrane attachment signals are interrelated in the process of the complex control of membrane targeting of G proteins remain unelucidated. This review focuses on the mechanisms by which mammalian Gα subunits of G proteins interact with lipids and the factors responsible for the specificity of membrane association. We summarize recent data on how these signaling proteins are precisely targeted to a specific site in the membrane region by introducing well-defined modifications as well as through the presence of polybasic regions within these proteins and interactions with other components of the heterocomplex.
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Affiliation(s)
- Agnieszka Polit
- Department of Physical Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland; (P.M.); (E.B.)
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11
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Diversity of the Gβγ complexes defines spatial and temporal bias of GPCR signaling. Cell Syst 2021; 12:324-337.e5. [PMID: 33667409 DOI: 10.1016/j.cels.2021.02.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 12/09/2020] [Accepted: 02/04/2021] [Indexed: 01/04/2023]
Abstract
The signal transduction by G-protein-coupled receptors (GPCRs) is mediated by heterotrimeric G proteins composed from one of the 16 Gα subunits and the inseparable Gβγ complex assembled from a repertoire of 5 Gβ and 12 Gγ subunits. However, the functional role of compositional diversity in Gβγ complexes has been elusive. Using optical biosensors, we examined the function of all Gβγ combinations in living cells and uncovered two major roles of Gβγ diversity. First, we demonstrate that the identity of Gβγ subunits greatly influences the kinetics and efficacy of GPCR responses at the plasma membrane. Second, we show that different Gβγ combinations are selectively dispatched from the plasma membrane to various cellular organelles on a timescale from milliseconds to minutes. We describe the mechanisms regulating these processes and document their implications for GPCR signaling via various Gα subunits, thereby illustrating a role for the compositional diversity of G protein heterotrimers.
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12
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Zhang M, Gui M, Wang ZF, Gorgulla C, Yu JJ, Wu H, Sun ZYJ, Klenk C, Merklinger L, Morstein L, Hagn F, Plückthun A, Brown A, Nasr ML, Wagner G. Cryo-EM structure of an activated GPCR-G protein complex in lipid nanodiscs. Nat Struct Mol Biol 2021; 28:258-267. [PMID: 33633398 PMCID: PMC8176890 DOI: 10.1038/s41594-020-00554-6] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 12/16/2020] [Indexed: 02/07/2023]
Abstract
G-protein-coupled receptors (GPCRs) are the largest superfamily of transmembrane proteins and the targets of over 30% of currently marketed pharmaceuticals. Although several structures have been solved for GPCR-G protein complexes, few are in a lipid membrane environment. Here, we report cryo-EM structures of complexes of neurotensin, neurotensin receptor 1 and Gαi1β1γ1 in two conformational states, resolved to resolutions of 4.1 and 4.2 Å. The structures, determined in a lipid bilayer without any stabilizing antibodies or nanobodies, reveal an extended network of protein-protein interactions at the GPCR-G protein interface as compared to structures obtained in detergent micelles. The findings show that the lipid membrane modulates the structure and dynamics of complex formation and provide a molecular explanation for the stronger interaction between GPCRs and G proteins in lipid bilayers. We propose an allosteric mechanism for GDP release, providing new insights into the activation of G proteins for downstream signaling.
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Affiliation(s)
- Meng Zhang
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Miao Gui
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Zi-Fu Wang
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Christoph Gorgulla
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of physics, Faculty of Arts and Sciences, Harvard University, Cambridge, MA, USA
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - James J Yu
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Hao Wu
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Zhen-Yu J Sun
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Christoph Klenk
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | - Lisa Merklinger
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | - Lena Morstein
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | - Franz Hagn
- Bavarian NMR Center at the Department of Chemistry, Technical University of Munich, Garching, Germany
- Institute of Structural Biology, Helmholtz Center Munich, Neuherberg, Germany
| | - Andreas Plückthun
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | - Alan Brown
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
| | - Mahmoud L Nasr
- Department of Medicine, Division of Renal Medicine, Division of Engineering in Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
| | - Gerhard Wagner
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
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13
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Paramonov VM, Sahlgren C, Rivero-Müller A, Pulliainen AT. iGIST-A Kinetic Bioassay for Pertussis Toxin Based on Its Effect on Inhibitory GPCR Signaling. ACS Sens 2020; 5:3438-3448. [PMID: 33147407 PMCID: PMC7706119 DOI: 10.1021/acssensors.0c01340] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Detection of pertussis toxin (PTX) activity is instrumental for the development and manufacturing of pertussis vaccines. These quality and safety measures require thousands of mice annually. Here, we describe Interference in Gαi-mediated Signal Transduction (iGIST), an animal-free kinetic bioassay for detection of PTX, by measuring its effect on inhibitory G protein-coupled receptor (GPCR) signaling. PTX ADP-ribosylates inhibitory α-subunits of the heterotrimeric G proteins, thereby perturbing the inhibitory GPCR signaling. iGIST is based on HEK293 cells coexpressing a somatostatin receptor 2 (SSTR2), which is an inhibitory GPCR controllable by a high-affinity agonist octreotide; and a luminescent 3'5'-cyclic adenosine monophosphate (cAMP) probe. iGIST has a low sensitivity threshold in the pg/mL range of PTX, surpassing by 100-fold in a parallel analysis the currently used in vitro end-point technique to detect PTX, the cluster formation assay (CFA) in Chinese hamster ovary cells. iGIST also detects PTX in complex samples, i.e., a commercial PTX-toxoid-containing pertussis vaccine that was spiked with an active PTX. iGIST has an objective digital readout and is observer independent, offering prospects for automation. iGIST emerges as a promising animal-free alternative to detect PTX activity in the development and manufacturing of pertussis vaccines. iGIST is also expected to facilitate basic PTX research, including identification and characterization of novel compounds interfering with PTX.
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Affiliation(s)
- Valeriy M. Paramonov
- Institute of Biomedicine, Research Unit for Integrative Physiology and Pharmacology, University of Turku, Kiinamyllynkatu 10, FI-20520 Turku, Finland
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, FI-20520 Turku, Finland
- Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, FI-20500 Turku, Finland
| | - Cecilia Sahlgren
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, FI-20520 Turku, Finland
- Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, FI-20500 Turku, Finland
- Institute for Complex Molecular Systems, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands
| | - Adolfo Rivero-Müller
- Institute of Biomedicine, Research Unit for Integrative Physiology and Pharmacology, University of Turku, Kiinamyllynkatu 10, FI-20520 Turku, Finland
- Department of Biochemistry and Molecular Biology, Medical University of Lublin, 20-059 Lublin, Poland
| | - Arto T. Pulliainen
- Institute of Biomedicine, Research Unit for Infection and Immunity, University of Turku, Kiinamyllynkatu 10, FI-20520 Turku, Finland
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14
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Akamine S, Okuzono S, Yamamoto H, Setoyama D, Sagata N, Ohgidani M, Kato TA, Ishitani T, Kato H, Masuda K, Matsushita Y, Ono H, Ishizaki Y, Sanefuji M, Saitsu H, Matsumoto N, Kang D, Kanba S, Nakabeppu Y, Sakai Y, Ohga S. GNAO1 organizes the cytoskeletal remodeling and firing of developing neurons. FASEB J 2020; 34:16601-16621. [PMID: 33107105 DOI: 10.1096/fj.202001113r] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 09/03/2020] [Accepted: 10/13/2020] [Indexed: 01/03/2023]
Abstract
Developmental and epileptic encephalopathy (DEE) represents a group of neurodevelopmental disorders characterized by infantile-onset intractable seizures and unfavorable prognosis of psychomotor development. To date, hundreds of genes have been linked to the onset of DEE. GNAO1 is a DEE-associated gene encoding the alpha-O1 subunit of guanine nucleotide-binding protein (GαO ). Despite the increasing number of reported children with GNAO1 encephalopathy, the molecular mechanisms underlying their neurodevelopmental phenotypes remain elusive. We herein present that co-immunoprecipitation and mass spectrometry analyses identified another DEE-associated protein, SPTAN1, as an interacting partner of GαO . Silencing of endogenous Gnao1 attenuated the neurite outgrowth and calcium-dependent signaling. Inactivation of GNAO1 in human-induced pluripotent stem cells gave rise to anomalous brain organoids that only weakly expressed SPTAN1 and Ankyrin-G. Furthermore, GNAO1-deficient organoids failed to conduct synchronized firing to adjacent neurons. These data indicate that GαO and other DEE-associated proteins organize the cytoskeletal remodeling and functional polarity of neurons in the developing brain.
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Affiliation(s)
- Satoshi Akamine
- Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Sayaka Okuzono
- Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hiroyuki Yamamoto
- Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Daiki Setoyama
- Department of Clinical Chemistry and Laboratory Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Noriaki Sagata
- Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Masahiro Ohgidani
- Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Takahiro A Kato
- Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Tohru Ishitani
- Division of Integrated Signaling Systems, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Japan.,Department of Homeostatic Regulation, Division of Cellular and Molecular Biology. Research Institute for Microbial Diseases, Osaka University, Suita, Japan
| | - Hiroki Kato
- Division of Oral Biological Sciences, Department of Molecular Cell Biology and Oral Anatomy, Graduate School of Dental Science, Kyushu University, Fukuoka, Japan
| | - Keiji Masuda
- Section of Oral Medicine for Children, Division of Oral Health, Growth and Development, Faculty of Dental Science, Kyushu University, Fukuoka, Japan
| | - Yuki Matsushita
- Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hiroaki Ono
- Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yoshito Ishizaki
- Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Masafumi Sanefuji
- Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hirotomo Saitsu
- Department of Biochemistry, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Dongchon Kang
- Department of Clinical Chemistry and Laboratory Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Shigenobu Kanba
- Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yusaku Nakabeppu
- Division of Neurofunctional Genomics, Department of Immunobiology and Neuroscience, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Yasunari Sakai
- Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Shouichi Ohga
- Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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15
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Mechanisms and Regulation of Neuronal GABA B Receptor-Dependent Signaling. Curr Top Behav Neurosci 2020; 52:39-79. [PMID: 32808092 DOI: 10.1007/7854_2020_129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
γ-Aminobutyric acid B receptors (GABABRs) are broadly expressed throughout the central nervous system where they play an important role in regulating neuronal excitability and synaptic transmission. GABABRs are G protein-coupled receptors that mediate slow and sustained inhibitory actions via modulation of several downstream effector enzymes and ion channels. GABABRs are obligate heterodimers that associate with diverse arrays of proteins to form modular complexes that carry out distinct physiological functions. GABABR-dependent signaling is fine-tuned and regulated through a multitude of mechanisms that are relevant to physiological and pathophysiological states. This review summarizes the current knowledge on GABABR signal transduction and discusses key factors that influence the strength and sensitivity of GABABR-dependent signaling in neurons.
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16
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Gupte TM, Ritt M, Dysthe M, Malik RU, Sivaramakrishnan S. Minute-scale persistence of a GPCR conformation state triggered by non-cognate G protein interactions primes signaling. Nat Commun 2019; 10:4836. [PMID: 31645561 PMCID: PMC6811539 DOI: 10.1038/s41467-019-12755-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 09/17/2019] [Indexed: 02/01/2023] Open
Abstract
Despite the crowded nature of the cellular milieu, ligand-GPCR-G protein interactions are traditionally viewed as spatially and temporally isolated events. In contrast, recent reports suggest the spatial and temporal coupling of receptor-effector interactions, with the potential to diversify downstream responses. In this study, we combine protein engineering of GPCR-G protein interactions with affinity sequestration and photo-manipulation of the crucial Gα C terminus, to demonstrate the temporal coupling of cognate and non-cognate G protein interactions through priming of the GPCR conformation. We find that interactions of the Gαs and Gαq C termini with the β2-adrenergic receptor (β2-AR), targeted at the G-protein-binding site, enhance Gs activation and cyclic AMP levels. β2-AR-Gα C termini interactions alter receptor conformation, which persists for ~90 s following Gα C terminus dissociation. Non-cognate G-protein expression levels impact cognate signaling in cells. Our study demonstrates temporal allostery in GPCRs, with implications for the modulation of downstream responses through the canonical G-protein-binding interface.
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Affiliation(s)
- Tejas M Gupte
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Twin-Cities, Minneapolis, Minnesota, 55455, USA
| | - Michael Ritt
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Twin-Cities, Minneapolis, Minnesota, 55455, USA
| | - Matthew Dysthe
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Twin-Cities, Minneapolis, Minnesota, 55455, USA
| | - Rabia U Malik
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Twin-Cities, Minneapolis, Minnesota, 55455, USA
| | - Sivaraj Sivaramakrishnan
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Twin-Cities, Minneapolis, Minnesota, 55455, USA.
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17
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Mystek P, Rysiewicz B, Gregrowicz J, Dziedzicka-Wasylewska M, Polit A. Gγ and Gα Identity Dictate a G-Protein Heterotrimer Plasma Membrane Targeting. Cells 2019; 8:E1246. [PMID: 31614907 PMCID: PMC6829862 DOI: 10.3390/cells8101246] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 10/10/2019] [Accepted: 10/11/2019] [Indexed: 12/18/2022] Open
Abstract
Heterotrimeric G-proteins along with G-protein-coupled receptors (GPCRs) regulate many biochemical functions by relaying the information from the plasma membrane to the inside of the cell. The lipid modifications of Gα and Gγ subunits, together with the charged regions on the membrane interaction surface, provide a peculiar pattern for various heterotrimeric complexes. In a previous study, we found that Gαs and Gαi3 prefer different types of membrane-anchor and subclass-specific lipid domains. In the present report, we examine the role of distinct Gγ subunits in the membrane localization and spatiotemporal dynamics of Gαs and Gαi3 heterotrimers. We characterized lateral diffusion and G-protein subunit interactions in living cells using fluorescence recovery after photobleaching (FRAP) microscopy and fluorescence resonance energy transfer (FRET) detected by fluorescence lifetime imaging microscopy (FLIM), respectively. The interaction of Gγ subunits with specific lipids was confirmed, and thus the modulation of heterotrimeric G-protein localization. However, the Gα subunit also modulates trimer localization, and so the membrane distribution of heterotrimeric G-proteins is not dependent on Gγ only.
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Affiliation(s)
- Paweł Mystek
- Department of Physical Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland.
| | - Beata Rysiewicz
- Department of Physical Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland.
| | - Jan Gregrowicz
- Department of Physical Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland.
| | - Marta Dziedzicka-Wasylewska
- Department of Physical Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland.
| | - Agnieszka Polit
- Department of Physical Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland.
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18
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Kato HE, Zhang Y, Hu H, Suomivuori CM, Kadji FMN, Aoki J, Krishna Kumar K, Fonseca R, Hilger D, Huang W, Latorraca NR, Inoue A, Dror RO, Kobilka BK, Skiniotis G. Conformational transitions of a neurotensin receptor 1-G i1 complex. Nature 2019; 572:80-85. [PMID: 31243364 PMCID: PMC7065593 DOI: 10.1038/s41586-019-1337-6] [Citation(s) in RCA: 160] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 05/31/2019] [Indexed: 01/14/2023]
Abstract
Neurotensin receptor 1 (NTSR1) is a G-protein-coupled receptor (GPCR) that engages multiple subtypes of G protein, and is involved in the regulation of blood pressure, body temperature, weight and the response to pain. Here we present structures of human NTSR1 in complex with the agonist JMV449 and the heterotrimeric Gi1 protein, at a resolution of 3 Å. We identify two conformations: a canonical-state complex that is similar to recently reported GPCR-Gi/o complexes (in which the nucleotide-binding pocket adopts more flexible conformations that may facilitate nucleotide exchange), and a non-canonical state in which the G protein is rotated by about 45 degrees relative to the receptor and exhibits a more rigid nucleotide-binding pocket. In the non-canonical state, NTSR1 exhibits features of both active and inactive conformations, which suggests that the structure may represent an intermediate form along the activation pathway of G proteins. This structural information, complemented by molecular dynamics simulations and functional studies, provides insights into the complex process of G-protein activation.
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Affiliation(s)
- Hideaki E Kato
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Komaba Institute for Science, The University of Tokyo, Tokyo, Japan
| | - Yan Zhang
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Pathology of Sir Run Run Shaw Hospital, Department of Biophysics, Zhejiang University School of Medicine, Hangzhou, China
| | - Hongli Hu
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Carl-Mikael Suomivuori
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Computer Science, Stanford University, Stanford, CA, USA
- Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA, USA
| | | | - Junken Aoki
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Kaavya Krishna Kumar
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Rasmus Fonseca
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Computer Science, University of Copenhagen, Copenhagen, Denmark
| | - Daniel Hilger
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Weijiao Huang
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Naomi R Latorraca
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Computer Science, Stanford University, Stanford, CA, USA
- Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA, USA
- Biophysics Program, Stanford University, Stanford, CA, USA
| | - Asuka Inoue
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Ron O Dror
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Computer Science, Stanford University, Stanford, CA, USA
- Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA, USA
- Biophysics Program, Stanford University, Stanford, CA, USA
| | - Brian K Kobilka
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA.
| | - Georgios Skiniotis
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA.
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA.
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19
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Seyedabadi M, Ghahremani MH, Albert PR. Biased signaling of G protein coupled receptors (GPCRs): Molecular determinants of GPCR/transducer selectivity and therapeutic potential. Pharmacol Ther 2019; 200:148-178. [PMID: 31075355 DOI: 10.1016/j.pharmthera.2019.05.006] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 04/26/2019] [Indexed: 02/07/2023]
Abstract
G protein coupled receptors (GPCRs) convey signals across membranes via interaction with G proteins. Originally, an individual GPCR was thought to signal through one G protein family, comprising cognate G proteins that mediate canonical receptor signaling. However, several deviations from canonical signaling pathways for GPCRs have been described. It is now clear that GPCRs can engage with multiple G proteins and the line between cognate and non-cognate signaling is increasingly blurred. Furthermore, GPCRs couple to non-G protein transducers, including β-arrestins or other scaffold proteins, to initiate additional signaling cascades. Receptor/transducer selectivity is dictated by agonist-induced receptor conformations as well as by collateral factors. In particular, ligands stabilize distinct receptor conformations to preferentially activate certain pathways, designated 'biased signaling'. In this regard, receptor sequence alignment and mutagenesis have helped to identify key receptor domains for receptor/transducer specificity. Furthermore, molecular structures of GPCRs bound to different ligands or transducers have provided detailed insights into mechanisms of coupling selectivity. However, receptor dimerization, compartmentalization, and trafficking, receptor-transducer-effector stoichiometry, and ligand residence and exposure times can each affect GPCR coupling. Extrinsic factors including cell type or assay conditions can also influence receptor signaling. Understanding these factors may lead to the development of improved biased ligands with the potential to enhance therapeutic benefit, while minimizing adverse effects. In this review, evidence for ligand-specific GPCR signaling toward different transducers or pathways is elaborated. Furthermore, molecular determinants of biased signaling toward these pathways and relevant examples of the potential clinical benefits and pitfalls of biased ligands are discussed.
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Affiliation(s)
- Mohammad Seyedabadi
- Department of Pharmacology, School of Medicine, Bushehr University of Medical Sciences, Iran; Education Development Center, Bushehr University of Medical Sciences, Iran
| | | | - Paul R Albert
- Ottawa Hospital Research Institute, Neuroscience, University of Ottawa, Canada.
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20
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Gupta K, Tölzer C, Sari-Ak D, Fitzgerald DJ, Schaffitzel C, Berger I. MultiBac: Baculovirus-Mediated Multigene DNA Cargo Delivery in Insect and Mammalian Cells. Viruses 2019; 11:E198. [PMID: 30813511 PMCID: PMC6466381 DOI: 10.3390/v11030198] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/14/2019] [Accepted: 02/21/2019] [Indexed: 12/22/2022] Open
Abstract
The baculovirus/insect cell system (BICS) is widely used in academia and industry to produce eukaryotic proteins for many applications, ranging from structure analysis to drug screening and the provision of protein biologics and therapeutics. Multi-protein complexes have emerged as vital catalysts of cellular function. In order to unlock the structure and mechanism of these essential molecular machines and decipher their function, we developed MultiBac, a BICS particularly tailored for heterologous multigene transfer and multi-protein complex production. Baculovirus is unique among common viral vectors in its capacity to accommodate very large quantities of heterologous DNA and to faithfully deliver this cargo to a host cell of choice. We exploited this beneficial feature to outfit insect cells with synthetic DNA circuitry conferring new functionality during heterologous protein expression, and developing customized MultiBac baculovirus variants in the process. By altering its tropism, recombinant baculovirions can be used for the highly efficient delivery of a customized DNA cargo in mammalian cells and tissues. Current advances in synthetic biology greatly facilitate the construction or recombinant baculoviral genomes for gene editing and genome engineering, mediated by a MultiBac baculovirus tailored to this purpose. Here, recent developments and exploits of the MultiBac system are presented and discussed.
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Affiliation(s)
- Kapil Gupta
- School of Biochemistry, Biomedical Sciences, University of Bristol, 1 Tankard's Close, Bristol BS8 1TD, UK.
- Bristol Synthetic Biology Centre BrisSynBio, University of Bristol, 4 Tyndall Ave, Bristol BS8 1TQ, UK.
| | - Christine Tölzer
- School of Biochemistry, Biomedical Sciences, University of Bristol, 1 Tankard's Close, Bristol BS8 1TD, UK.
- Bristol Synthetic Biology Centre BrisSynBio, University of Bristol, 4 Tyndall Ave, Bristol BS8 1TQ, UK.
| | - Duygu Sari-Ak
- European Molecular Biology Laboratory EMBL, 71 Avenue des Martyrs, 38000 Grenoble, France.
| | | | - Christiane Schaffitzel
- School of Biochemistry, Biomedical Sciences, University of Bristol, 1 Tankard's Close, Bristol BS8 1TD, UK.
- Bristol Synthetic Biology Centre BrisSynBio, University of Bristol, 4 Tyndall Ave, Bristol BS8 1TQ, UK.
| | - Imre Berger
- School of Biochemistry, Biomedical Sciences, University of Bristol, 1 Tankard's Close, Bristol BS8 1TD, UK.
- Bristol Synthetic Biology Centre BrisSynBio, University of Bristol, 4 Tyndall Ave, Bristol BS8 1TQ, UK.
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21
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The in vivo specificity of synaptic Gβ and Gγ subunits to the α 2a adrenergic receptor at CNS synapses. Sci Rep 2019; 9:1718. [PMID: 30737458 PMCID: PMC6368627 DOI: 10.1038/s41598-018-37222-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 11/26/2018] [Indexed: 11/21/2022] Open
Abstract
G proteins are major transducers of signals from G-protein coupled receptors (GPCRs). They are made up of α, β, and γ subunits, with 16 Gα, 5 Gβ and 12 Gγ subunits. Though much is known about the specificity of Gα subunits, the specificity of Gβγs activated by a given GPCR and that activate each effector in vivo is not known. Here, we examined the in vivo Gβγ specificity of presynaptic α2a-adrenergic receptors (α2aARs) in both adrenergic (auto-α2aARs) and non-adrenergic neurons (hetero-α2aARs) for the first time. With a quantitative MRM proteomic analysis of neuronal Gβ and Gγ subunits, and co-immunoprecipitation of tagged α2aARs from mouse models including transgenic FLAG-α2aARs and knock-in HA-α2aARs, we investigated the in vivo specificity of Gβ and Gγ subunits to auto-α2aARs and hetero-α2aARs activated with epinephrine to understand the role of Gβγ specificity in diverse physiological functions such as anesthetic sparing, and working memory enhancement. We detected Gβ2, Gγ2, Gγ3, and Gγ4 with activated auto α2aARs, whereas we found Gβ4 and Gγ12 preferentially interacted with activated hetero-α2aARs. Further understanding of in vivo Gβγ specificity to various GPCRs offers new insights into the multiplicity of genes for Gβ and Gγ, and the mechanisms underlying GPCR signaling through Gβγ subunits.
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Kumar A, Plückthun A. In vivo assembly and large-scale purification of a GPCR - Gα fusion with Gβγ, and characterization of the active complex. PLoS One 2019; 14:e0210131. [PMID: 30620756 PMCID: PMC6324789 DOI: 10.1371/journal.pone.0210131] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 12/04/2018] [Indexed: 12/13/2022] Open
Abstract
G protein coupled receptors (GPCRs) are central players in recognizing a variety of stimuli to mediate diverse cellular responses. This myriad of functions is accomplished by their modular interactions with downstream intracellular transducers, such as heterotrimeric G proteins and arrestins. Assembling a specific GPCR-G protein pair as a purified complex for their structural and functional investigations remains a challenging task, however, because of the low affinity of the interaction. Here, we optimized fusion constructs of the Gα subunit of the heterotrimeric G protein and engineered versions of rat Neurotensin receptor 1 (NTR1), coexpressed and assembled in vivo with Gβ and Gγ. This was achieved by using the baculovirus-based MultiBac system. We thus generated a functional receptor-G protein fusion complex, which can be efficiently purified using ligand-based affinity chromatography on large scales. Additionally, we utilized a purification method based on a designed ankyrin repeat protein tightly binding to Green Fluorescent Protein (GFP-DARPin) that may be used as a generic approach for a large-scale purification of GPCR-G protein fusion complexes for which no ligands column can be generated. The purification methods described herein will support future studies that aim to understand the structural and functional framework of GPCR activation and signaling.
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Affiliation(s)
- Abhinav Kumar
- Department of Biochemistry, University of Zürich, Zürich, Switzerland
| | - Andreas Plückthun
- Department of Biochemistry, University of Zürich, Zürich, Switzerland
- * E-mail:
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23
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Abstract
Modulation of neurotransmitter exocytosis by activated Gi/o coupled G-protein coupled receptors (GPCRs) is a universal regulatory mechanism used both to avoid overstimulation and to influence circuitry. One of the known modulation mechanisms is the interaction between Gβγ and the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNAREs). There are 5 Gβ and 12 Gγ subunits, but specific Gβγs activated by a given GPCR and the specificity to effectors, such as SNARE, in vivo are not known. Although less studied, Gβγ binding to the exocytic fusion machinery (i.e. SNARE) provides a more direct regulatory mechanism for neurotransmitter release. Here, we review some recent insights in the architecture of the synaptic terminal, modulation of synaptic transmission, and implications of G protein modulation of synaptic transmission in diseases. Numerous presynaptic proteins are involved in the architecture of synaptic terminals, particularly the active zone, and their importance in the regulation of exocytosis is still not completely understood. Further understanding of the Gβγ-SNARE interaction and the architecture and mechanisms of exocytosis may lead to the discovery of novel therapeutic targets to help patients with various disorders such as hypertension, attention-deficit/hyperactivity disorder, post-traumatic stress disorder, and acute/chronic pain.
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Affiliation(s)
- Yun Young Yim
- Department of Pharmacology, Vanderbilt University, Nashville 37232-6600, TN, United States
| | - Zack Zurawski
- Department of Pharmacology, Vanderbilt University, Nashville 37232-6600, TN, United States
| | - Heidi Hamm
- Department of Pharmacology, Vanderbilt University, Nashville 37232-6600, TN, United States.
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Mattern A, Machka F, Wickleder MS, Ilyaskina OS, Bünemann M, Diener M, Pouokam E. Potentiation of the activation of cholinergic receptors by multivalent presentation of ligands supported on gold nanoparticles. Org Biomol Chem 2018; 16:6680-6687. [PMID: 30177977 DOI: 10.1039/c8ob01686k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Gold nanoparticles (NP) with a functionalized ligand shell offer the possibility to potentiate the action of agonists at the receptor site by multivalency. In order to find out whether this can be realized for the pharmacologically important class of cholinergic receptors known to be involved in the regulation of most organ functions, carbachol-functionalized gold NPs (Au-MUDA-CCh) with an average diameter of 14 nm were synthesized. As functional read-out, cholinergic agonist-induced anion secretion was measured as increase in short-circuit current (Isc) across rat proximal colon in Ussing chambers. Similarly to the corresponding native agonist acetylcholine, Au-MUDA-CCh induced a concentration-dependent increase in Isc, which represents chloride secretion across the epithelium. This response was inhibited by atropine and hexamethonium indicating the activation of muscarinic and nicotinic receptors by the functionalized NPs. A strong potentiation of ligand-receptor interaction was a key benefit of functionalized NPs over native agonists. This was observed with physiological approaches as measurements of changes in Isc revealed a nearly equivalent response evoked by 1 pM Au-MUDA-CCh and 500 nM native CCh. To better determine this potentiation at the receptor level, pharmacological approaches based on the signaling cascade of ACh-induced activation of muscarinic receptors were used. FRET (Förster Resonance Energy Transfer) measurements performed on HEK293T cells transiently transfected with M3-R, Gαq-YFP, Gβ1-wt and CFP-Gγ2, revealed that both Au-MUDA-CCh and native CCh activated G-proteins with EC50 amounting to 127 ± 0.44 fM and 224 ± 7.12 nM, respectively. Thus, the functionalization of the NPs with CCh yields a potentiation by over 106, a property that could find usage in specific targeting, activation and compensation of pathologically reduced expression of receptors of interest.
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Affiliation(s)
- A Mattern
- Institute of Inorganic Chemistry, University of Cologne, Cologne, Germany
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25
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Yen HY, Hoi KK, Liko I, Hedger G, Horrell MR, Song W, Wu D, Heine P, Warne T, Lee Y, Carpenter B, Plückthun A, Tate CG, Sansom MSP, Robinson CV. PtdIns(4,5)P 2 stabilizes active states of GPCRs and enhances selectivity of G-protein coupling. Nature 2018; 559:423-427. [PMID: 29995853 PMCID: PMC6059376 DOI: 10.1038/s41586-018-0325-6] [Citation(s) in RCA: 206] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 05/14/2018] [Indexed: 11/21/2022]
Abstract
G-protein-coupled receptors (GPCRs) are involved in many physiological processes and are therefore key drug targets1. Although detailed structural information is available for GPCRs, the effects of lipids on the receptors, and on downstream coupling of GPCRs to G proteins are largely unknown. Here we use native mass spectrometry to identify endogenous lipids bound to three class A GPCRs. We observed preferential binding of phosphatidylinositol-4,5-bisphosphate (PtdIns(4,5)P2) over related lipids and confirm that the intracellular surface of the receptors contain hotspots for PtdIns(4,5)P2 binding. Endogenous lipids were also observed bound directly to the trimeric Gαsβγ protein complex of the adenosine A2A receptor (A2AR) in the gas phase. Using engineered Gα subunits (mini-Gαs, mini-Gαi and mini-Gα12)2, we demonstrate that the complex of mini-Gαs with the β1 adrenergic receptor (β1AR) is stabilized by the binding of two PtdIns(4,5)P2 molecules. By contrast, PtdIns(4,5)P2 does not stabilize coupling between β1AR and other Gα subunits (mini-Gαi or mini-Gα12) or a high-affinity nanobody. Other endogenous lipids that bind to these receptors have no effect on coupling, highlighting the specificity of PtdIns(4,5)P2. Calculations of potential of mean force and increased GTP turnover by the activated neurotensin receptor when coupled to trimeric Gαiβγ complex in the presence of PtdIns(4,5)P2 provide further evidence for a specific effect of PtdIns(4,5)P2 on coupling. We identify key residues on cognate Gα subunits through which PtdIns(4,5)P2 forms bridging interactions with basic residues on class A GPCRs. These modulating effects of lipids on receptors suggest consequences for understanding function, G-protein selectivity and drug targeting of class A GPCRs.
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MESH Headings
- Animals
- GTP-Binding Protein alpha Subunits, Gi-Go/metabolism
- GTP-Binding Protein alpha Subunits, Gs/metabolism
- Heterotrimeric GTP-Binding Proteins/metabolism
- Humans
- Molecular Dynamics Simulation
- Phosphatidylinositol 4,5-Diphosphate/metabolism
- Protein Stability
- Rats
- Receptors, Adrenergic, alpha-2/chemistry
- Receptors, Adrenergic, alpha-2/genetics
- Receptors, Adrenergic, alpha-2/metabolism
- Receptors, Adrenergic, beta-1/chemistry
- Receptors, Adrenergic, beta-1/genetics
- Receptors, Adrenergic, beta-1/metabolism
- Receptors, G-Protein-Coupled/chemistry
- Receptors, G-Protein-Coupled/genetics
- Receptors, G-Protein-Coupled/metabolism
- Receptors, Neurotensin/chemistry
- Receptors, Neurotensin/genetics
- Receptors, Neurotensin/metabolism
- Single-Chain Antibodies/chemistry
- Single-Chain Antibodies/metabolism
- Substrate Specificity
- Turkeys
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Affiliation(s)
- Hsin-Yung Yen
- Chemical Research Laboratory, University of Oxford, Oxford, UK
- OMass Technologies, Kidlington, UK
| | - Kin Kuan Hoi
- Chemical Research Laboratory, University of Oxford, Oxford, UK
| | - Idlir Liko
- Chemical Research Laboratory, University of Oxford, Oxford, UK
- OMass Technologies, Kidlington, UK
| | - George Hedger
- Department of Biochemistry, University of Oxford, Oxford, UK
| | | | - Wanling Song
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Di Wu
- Chemical Research Laboratory, University of Oxford, Oxford, UK
| | - Philipp Heine
- Biochemisches Institut, Universität Zürich, Zurich, Switzerland
| | - Tony Warne
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Yang Lee
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Byron Carpenter
- MRC Laboratory of Molecular Biology, Cambridge, UK
- Warwick Integrative Synthetic Biology Centre, School of Life Sciences, The University of Warwick, Coventry, UK
| | | | | | - Mark S P Sansom
- Department of Biochemistry, University of Oxford, Oxford, UK.
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Ilyaskina OS, Lemoine H, Bünemann M. Lifetime of muscarinic receptor-G-protein complexes determines coupling efficiency and G-protein subtype selectivity. Proc Natl Acad Sci U S A 2018; 115:5016-5021. [PMID: 29686069 PMCID: PMC5948956 DOI: 10.1073/pnas.1715751115] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
G-protein-coupled receptors (GPCRs) are essential for the detection of extracellular stimuli by cells and transfer the encoded information via the activation of functionally distinct subsets of heterotrimeric G proteins into intracellular signals. Despite enormous achievements toward understanding GPCR structures, major aspects of the GPCR-G-protein selectivity mechanism remain unresolved. As this can be attributed to the lack of suitable and broadly applicable assays, we set out to develop a quantitative FRET-based assay to study kinetics and affinities of G protein binding to activated GPCRs in membranes of permeabilized cells in the absence of nucleotides. We measured the association and dissociation kinetics of agonist-induced binding of Gi/o, Gq/11, Gs, and G12/13 proteins to muscarinic M1, M2, and M3 receptors in the absence of nucleotides between fluorescently labeled G proteins and receptors expressed in mammalian cells. Our results show a strong quantitative correlation between not the on-rates of G-protein-M3-R interactions but rather the affinities of Gq and Go proteins to M3-Rs, their GPCR-G-protein lifetime and their coupling efficiencies determined in intact cells, suggesting that the G-protein subtype-specific affinity to the activated receptor in the absence of nucleotides is, in fact, a major determinant of the coupling efficiency. Our broadly applicable FRET-based assay represents a fast and reliable method to quantify the intrinsic affinity and relative coupling selectivity of GPCRs toward all G-protein subtypes.
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Affiliation(s)
- Olga S Ilyaskina
- Department of Pharmacology and Clinical Pharmacy, Faculty of Pharmacy, University of Marburg, 35032 Marburg, Germany
| | - Horst Lemoine
- Department of Laser Medicine, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Moritz Bünemann
- Department of Pharmacology and Clinical Pharmacy, Faculty of Pharmacy, University of Marburg, 35032 Marburg, Germany;
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27
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The G-protein γ subunit of Phytophthora infestans is involved in sporangial development. Fungal Genet Biol 2018; 116:73-82. [PMID: 29704555 DOI: 10.1016/j.fgb.2018.04.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 04/17/2018] [Accepted: 04/21/2018] [Indexed: 11/23/2022]
Abstract
The oomycete Phytophthora infestans is a notorious plant pathogen with potato and tomato as its primary hosts. Previous research showed that the heterotrimeric G-protein subunits Gα and Gβ have a role in zoospore motility and virulence, and sporangial development, respectively. Here, we present analyses of the gene encoding a Gγ subunit in P. infestans, Pigpg1. The overall similarity of PiGPG1 with non-oomycete Gγ subunits is low, with only the most conserved amino acids maintained, but similarity with its homologs in other oomycetes is high. Pigpg1 is expressed in all life stages and shows a similar expression profile as the gene encoding the Gβ subunit, Pigpb1. To elucidate its function, transformants were generated in which Pigpg1 is silenced or overexpressed and their phenotypes were analyzed. Pigpg1-silenced lines produce less sporangia, which are malformed. Altogether, the results show that PiGPG1 is crucial for proper sporangia development and zoosporogenesis. PiGPG1 is a functional Gγ, and likely forms a dimer with PiGPB1 that mediates signaling.
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28
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Mansouri M, Berger P. Multigene delivery in mammalian cells: Recent advances and applications. Biotechnol Adv 2018; 36:871-879. [PMID: 29374595 DOI: 10.1016/j.biotechadv.2018.01.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 01/19/2018] [Accepted: 01/20/2018] [Indexed: 12/27/2022]
Abstract
Systems for multigene delivery in mammalian cells, particularly in the context of genome engineering, have gained a lot of attention in biomolecular research and medicine. Initially these methods were based on RNA polymerase II promoters and were used for the production of protein complexes and for applications in cell biology such as reprogramming of somatic cells to stem cells. Emerging technologies such as CRISPR/Cas9-based genome engineering, which enable any alteration at the genomic level of an organism, require additional elements including U6-driven expression cassettes for RNA expression and homology constructs for designed genome modifications. For these applications, systems with high DNA capacity, flexibility and transfer rates are needed. In this article, we briefly give an update on some of recent strategies that facilitate multigene assembly and delivery into mammalian cells. Also, we review applications in various fields of biology that rely on multigene delivery systems.
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Affiliation(s)
- Maysam Mansouri
- Paul Scherrer Institute, Biomolecular Research, Applied Molecular Biology, CH-5232 Villigen, Switzerland
| | - Philipp Berger
- Paul Scherrer Institute, Biomolecular Research, Applied Molecular Biology, CH-5232 Villigen, Switzerland.
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29
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Roy Choudhury S, Pandey S. Recently duplicated plant heterotrimeric Gα proteins with subtle biochemical differences influence specific outcomes of signal-response coupling. J Biol Chem 2017; 292:16188-16198. [PMID: 28827312 PMCID: PMC5625049 DOI: 10.1074/jbc.m117.793380] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 08/10/2017] [Indexed: 12/31/2022] Open
Abstract
Heterotrimeric G-proteins, comprising Gα, Gβ, and Gγ subunits, regulate key signaling processes in eukaryotes. The Gα subunit determines the status of signaling by switching between inactive GDP-bound and active GTP-bound forms. Unlike animal systems, in which multiple Gα proteins with variable biochemical properties exist, plants have fewer, highly similar Gα subunits that have resulted from recent genome duplications. These proteins exhibit subtle differences in their GTP-binding, GDP/GTP-exchange, and GTP-hydrolysis activities, but the extent to which these differences contribute to affect plant signaling and development remains unknown. To evaluate this, we expressed native and engineered Gα proteins from soybean in an Arabidopsis Gα-null background and studied their effects on modulating a range of developmental and hormonal signaling phenotypes. Our results indicated that inherent biochemical differences in these highly similar Gα proteins are biologically relevant, and some proteins are more flexible than others in influencing the outcomes of specific signals. These observations suggest that alterations in the rate of the G-protein cycle itself may contribute to the specificity of response regulation in plants by affecting the duration of active signaling and/or by the formation of distinct protein-protein complexes. In species such as Arabidopsis having a single canonical Gα, this rate could be affected by regulatory proteins in the presence of specific signals, whereas in plants with multiple Gα proteins, an even more complex regulation may exist, which likely contributes to the specificity of signal-response coupling.
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Affiliation(s)
| | - Sona Pandey
- From the Donald Danforth Plant Science Center, St. Louis, Missouri 63132
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30
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Routledge SJ, Ladds G, Poyner DR. The effects of RAMPs upon cell signalling. Mol Cell Endocrinol 2017; 449:12-20. [PMID: 28390954 DOI: 10.1016/j.mce.2017.03.033] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 02/01/2017] [Accepted: 03/24/2017] [Indexed: 12/29/2022]
Abstract
G protein-coupled receptors (GPCRs) play a vital role in signal transduction. It is now clear that numerous other molecules within the cell and at the cell surface interact with GPCRs to modulate their signalling properties. Receptor activity modifying proteins (RAMPs) are a group of single transmembrane domain proteins which have been predominantly demonstrated to interact with Family B GPCRs, but interactions with Family A and C receptors have recently begun to emerge. These interactions can influence cell surface expression, ligand binding preferences and G protein-coupling, thus modulating GPCR signal transduction. There is still a great deal of research to be conducted into the effects of RAMPs on GPCR signalling; their effects upon Family B GPCRs are still not fully documented, in addition to their potential interactions with Family A and C GPCRs. New interactions could have a significant impact on the development of therapeutics.
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Affiliation(s)
- Sarah J Routledge
- Department of Pharmacology, University of Cambridge, Cambridge CB2 1PD, United Kingdom.
| | - Graham Ladds
- Department of Pharmacology, University of Cambridge, Cambridge CB2 1PD, United Kingdom
| | - David R Poyner
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, United Kingdom
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31
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Bolivar JH, Muñoz-García JC, Castro-Dopico T, Dijkman PM, Stansfeld PJ, Watts A. Interaction of lipids with the neurotensin receptor 1. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:1278-87. [DOI: 10.1016/j.bbamem.2016.02.032] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 02/02/2016] [Accepted: 02/24/2016] [Indexed: 10/22/2022]
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32
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Muntean BS, Martemyanov KA. Association with the Plasma Membrane Is Sufficient for Potentiating Catalytic Activity of Regulators of G Protein Signaling (RGS) Proteins of the R7 Subfamily. J Biol Chem 2016; 291:7195-204. [PMID: 26811338 PMCID: PMC4807299 DOI: 10.1074/jbc.m115.713446] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Revised: 01/21/2016] [Indexed: 12/23/2022] Open
Abstract
Regulators of G protein Signaling (RGS) promote deactivation of heterotrimeric G proteins thus controlling the magnitude and kinetics of responses mediated by G protein-coupled receptors (GPCR). In the nervous system, RGS7 and RGS9-2 play essential role in vision, reward processing, and movement control. Both RGS7 and RGS9-2 belong to the R7 subfamily of RGS proteins that form macromolecular complexes with R7-binding protein (R7BP). R7BP targets RGS proteins to the plasma membrane and augments their GTPase-accelerating protein (GAP) activity, ultimately accelerating deactivation of G protein signaling. However, it remains unclear if R7BP serves exclusively as a membrane anchoring subunit or further modulates RGS proteins to increase their GAP activity. To directly answer this question, we utilized a rapidly reversible chemically induced protein dimerization system that enabled us to control RGS localization independent from R7BP in living cells. To monitor kinetics of Gα deactivation, we coupled this strategy with measuring changes in the GAP activity by bioluminescence resonance energy transfer-based assay in a cellular system containing μ-opioid receptor. This approach was used to correlate changes in RGS localization and activity in the presence or absence of R7BP. Strikingly, we observed that RGS activity is augmented by membrane recruitment, in an orientation independent manner with no additional contributions provided by R7BP. These findings argue that the association of R7 RGS proteins with the membrane environment provides a major direct contribution to modulation of their GAP activity.
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Affiliation(s)
- Brian S Muntean
- From the Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida 33458
| | - Kirill A Martemyanov
- From the Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida 33458
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33
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Miller JC, Chezem WR, Clay NK. Ternary WD40 Repeat-Containing Protein Complexes: Evolution, Composition and Roles in Plant Immunity. FRONTIERS IN PLANT SCIENCE 2016; 6:1108. [PMID: 26779203 PMCID: PMC4703829 DOI: 10.3389/fpls.2015.01108] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Accepted: 11/23/2015] [Indexed: 05/18/2023]
Abstract
Plants, like mammals, rely on their innate immune system to perceive and discriminate among the majority of their microbial pathogens. Unlike mammals, plants respond to this molecular dialog by unleashing a complex chemical arsenal of defense metabolites to resist or evade pathogen infection. In basal or non-host resistance, plants utilize signal transduction pathways to detect "non-self," "damaged-self," and "altered-self"- associated molecular patterns and translate these "danger" signals into largely inducible chemical defenses. The WD40 repeat (WDR)-containing proteins Gβ and TTG1 are constituents of two independent ternary protein complexes functioning at opposite ends of a plant immune signaling pathway. They are also encoded by single-copy genes that are ubiquitous in higher plants, implying the limited diversity and functional conservation of their respective complexes. In this review, we summarize what is currently known about the evolutionary history of these WDR-containing ternary complexes, their repertoire and combinatorial interactions, and their downstream effectors and pathways in plant defense.
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Affiliation(s)
- Jimi C. Miller
- Department of Molecular Biophysics and Biochemistry, Yale UniversityNew Haven, CT, USA
| | - William R. Chezem
- Department of Molecular, Cellular and Developmental Biology, Yale UniversityNew Haven, CT, USA
| | - Nicole K. Clay
- Department of Molecular, Cellular and Developmental Biology, Yale UniversityNew Haven, CT, USA
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Abstract
Five syndromes share predominantly hyperplastic glands with a primary excess of hormones: neonatal severe primary hyperparathyroidism, from homozygous mutated CASR, begins severely in utero; congenital non-autoimmune thyrotoxicosis, from mutated TSHR, varies from severe with fetal onset to mild with adult onset; familial male-limited precocious puberty, from mutated LHR, expresses testosterone oversecretion in young boys; hereditary ovarian hyperstimulation syndrome, from mutated FSHR, expresses symptomatic systemic vascular permeabilities during pregnancy; and familial hyperaldosteronism type IIIA, from mutated KCNJ5, presents in young children with hypertension and hypokalemia. The grouping of these five syndromes highlights predominant hyperplasia as a stable tissue endpoint and as their tissue stage for all of the hormone excess. Comparisons were made among this and two other groups of syndromes, forming a continuum of gland staging: predominant oversecretions express little or no hyperplasia; predominant hyperplasias express little or no neoplasia; and predominant neoplasias express nodules, adenomas, or cancers. Hyperplasias may progress (5 of 5) to neoplastic stages while predominant oversecretions rarely do (1 of 6; frequencies differ P<0.02). Hyperplasias do not show tumor multiplicity (0 of 5) unlike neoplasias that do (13 of 19; P<0.02). Hyperplasias express mutation of a plasma membrane-bound sensor (5 of 5), while neoplasias rarely do (3 of 14; P<0.002). In conclusion, the multiple distinguishing themes within the hyperplasias establish a robust pathophysiology. It has the shared and novel feature of mutant sensors in the plasma membrane, suggesting that these are major contributors to hyperplasia.
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Affiliation(s)
- Stephen J Marx
- Genetics and Endocrinology SectionNational Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Building 10, Room 9C-103, Bethesda, Maryland 20892, USA
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35
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The Gαo Activator Mastoparan-7 Promotes Dendritic Spine Formation in Hippocampal Neurons. Neural Plast 2015; 2016:4258171. [PMID: 26881110 PMCID: PMC4736189 DOI: 10.1155/2016/4258171] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Revised: 07/26/2015] [Accepted: 08/27/2015] [Indexed: 11/17/2022] Open
Abstract
Mastoparan-7 (Mas-7), an analogue of the peptide mastoparan, which is derived from wasp venom, is a direct activator of Pertussis toxin- (PTX-) sensitive G proteins. Mas-7 produces several biological effects in different cell types; however, little is known about how Mas-7 influences mature hippocampal neurons. We examined the specific role of Mas-7 in the development of dendritic spines, the sites of excitatory synaptic contact that are crucial for synaptic plasticity. We report here that exposure of hippocampal neurons to a low dose of Mas-7 increases dendritic spine density and spine head width in a time-dependent manner. Additionally, Mas-7 enhances postsynaptic density protein-95 (PSD-95) clustering in neurites and activates Gαo signaling, increasing the intracellular Ca2+ concentration. To define the role of signaling intermediates, we measured the levels of phosphorylated protein kinase C (PKC), c-Jun N-terminal kinase (JNK), and calcium-calmodulin dependent protein kinase IIα (CaMKIIα) after Mas-7 treatment and determined that CaMKII activation is necessary for the Mas-7-dependent increase in dendritic spine density. Our results demonstrate a critical role for Gαo subunit signaling in the regulation of synapse formation.
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