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Song E, Ghil S. Crosstalk between cannabinoid receptor 2 and lysophosphatidic acid receptor 5. Biochem Biophys Res Commun 2023; 666:154-161. [PMID: 37187093 DOI: 10.1016/j.bbrc.2023.04.115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 04/29/2023] [Indexed: 05/17/2023]
Abstract
Cannabinoid receptor 2 (CB2) and lysophosphatidic acid receptor 5 (LPA5) are both classified as G-protein coupled receptors (GPCRs) activated by bioactive lipids and are highly expressed in colon cancer cells. However, crosstalk between two receptors and its potential effects on cancer cell physiology have not been fully elucidated. In the present study, the results of bioluminescence resonance energy transfer analysis showed that, among the LPA receptors, CB2 strongly and specifically interacted with LPA5. Both receptors were co-localized in the plasma membrane in the absence of agonists, and the receptors were co-internalized upon activation of either receptor alone or both receptors together. We further investigated the effects of expression of both receptors on cell proliferation and migration, and the molecular mechanisms underlying these effects in HCT116 colon cancer cells. Co-expression of receptors significantly increased cell proliferation and migration by increasing Akt phosphorylation and tumor progression-related gene expression, whereas no such effect was seen upon expression of either receptor alone. These results suggest the possibility of physical and functional crosstalk between CB2 and LPA5.
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Affiliation(s)
- Eunju Song
- Department of Life Science, Kyonggi University, Suwon, 16227, Republic of Korea
| | - Sungho Ghil
- Department of Life Science, Kyonggi University, Suwon, 16227, Republic of Korea.
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2
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Hong H, Yoon B, Ghil S. Interactions between lysophosphatidylinositol receptor GPR55 and sphingosine-1-phosphate receptor S1P 5 in live cells. Biochem Biophys Res Commun 2021; 570:53-59. [PMID: 34271437 DOI: 10.1016/j.bbrc.2021.07.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 07/07/2021] [Indexed: 01/19/2023]
Abstract
Lysophosphatidylinositol (LPI) and sphingosine-1-phosphate (S1P) are bioactive lipids implicated in various cellular events including proliferation, migration, and cancer progression. LPI and S1P act as ligands for G-protein coupled GPR55 and S1P receptors, respectively, and activate specific signaling pathways. Both receptors are highly expressed in various cancer tissues and associated with tumor progression. However, physical and functional crosstalk between the two receptors has not been elucidated to date. Bioluminescence resonance energy transfer (BRET) experiments in the current study showed that S1P5 strongly and specifically interacts with GPR55. We observed co-internalization of both receptors upon agonist stimulation. Notably, activation of one receptor induced co-internalization of the partner receptor. Next, we examined functional crosstalk of the two receptors. Interestingly, while activation of the individual receptors augmented cell proliferation, ERK phosphorylation and cancer-associated gene expression in HCT116 cells, co-activation of both receptors inhibited these stimulatory effects. Our collective findings indicate that GPR55 and S1P5 form a heterodimer and their co-activation attenuates the stimulatory activity of each receptor on colon cancer progression.
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Affiliation(s)
- Hahoon Hong
- Department of Life Science, Kyonggi University, Suwon, 16227, Republic of Korea
| | - Byoungsu Yoon
- Department of Life Science, Kyonggi University, Suwon, 16227, Republic of Korea.
| | - Sungho Ghil
- Department of Life Science, Kyonggi University, Suwon, 16227, Republic of Korea.
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3
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Bang G, Ghil S. BRET analysis reveals interaction between the lysophosphatidic acid receptor LPA2 and the lysophosphatidylinositol receptor GPR55 in live cells. FEBS Lett 2021; 595:1806-1818. [PMID: 33959968 DOI: 10.1002/1873-3468.14102] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 04/12/2021] [Accepted: 04/26/2021] [Indexed: 01/04/2023]
Abstract
Lysophosphatidic acid (LPA) and lysophosphatidylinositol bind to the G protein-coupled receptors (GPCRs) LPA and GPR55, respectively. LPA2 , a type 2 LPA receptor, and GPR55 are highly expressed in colon cancer and involved in cancer progression. However, crosstalk between the two receptors and potential effects on cellular physiology are not fully understood. Here, using BRET analysis, we found that LPA2 and GPR55 interact in live cells. In the presence of both receptors, LPA2 and/or GPR55 activation facilitated co-internalization, and activation of GPR55, uncoupled with Gαi , induced reduction of intracellular cAMP. Notably, co-activation of receptors synergistically triggered further decline in the cAMP level, promoted cell proliferation, and increased the expression of cancer progression-related genes, suggesting that physical and functional crosstalk between LPA2 and GRR55 is involved in cancer progression.
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Affiliation(s)
- Gwantae Bang
- Department of Life Science, Kyonggi University, Suwon, Korea
| | - Sungho Ghil
- Department of Life Science, Kyonggi University, Suwon, Korea
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Kim Y, Ghil S. Regulators of G-protein signaling, RGS2 and RGS4, inhibit protease-activated receptor 4-mediated signaling by forming a complex with the receptor and Gα in live cells. Cell Commun Signal 2020; 18:86. [PMID: 32517689 PMCID: PMC7285472 DOI: 10.1186/s12964-020-00552-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 03/11/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Protease-activated receptor 4 (PAR4) is a seven transmembrane G-protein coupled receptor (GPCR) activated by endogenous proteases, such as thrombin. PAR4 is involved in various pathophysiologies including cancer, inflammation, pain, and thrombosis. Although regulators of G-protein signaling (RGS) are known to modulate GPCR/Gα-mediated pathways, their specific effects on PAR4 are not fully understood at present. We previously reported that RGS proteins attenuate PAR1- and PAR2-mediated signaling through interactions with these receptors in conjunction with distinct Gα subunits. METHODS We employed a bioluminescence resonance energy transfer technique and confocal microscopy to examine potential interactions among PAR4, RGS, and Gα subunits. The inhibitory effects of RGS proteins on PAR4-mediated downstream signaling and cancer progression were additionally investigated by using several assays including ERK phosphorylation, calcium mobilization, RhoA activity, cancer cell proliferation, and related gene expression. RESULTS In live cells, RGS2 interacts with PAR4 in the presence of Gαq while RGS4 binding to PAR4 occurs in the presence of Gαq and Gα12/13. Co-expression of PAR4 and Gαq induced a shift in the subcellular localization of RGS2 and RGS4 from the cytoplasm to plasma membrane. Combined PAR4 and Gα12/13 expression additionally promoted translocation of RGS4 from the cytoplasm to the membrane. Both RGS2 and RGS4 abolished PAR4-activated ERK phosphorylation, calcium mobilization and RhoA activity, as well as PAR4-mediated colon cancer cell proliferation and related gene expression. CONCLUSIONS RGS2 and RGS4 forms ternary complex with PAR4 in Gα-dependent manner and inhibits its downstream signaling. Our findings support a novel physiological function of RGS2 and RGS4 as inhibitors of PAR4-mediated signaling through selective PAR4/RGS/Gα coupling. Video Abstract.
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Affiliation(s)
- Yukeyoung Kim
- Department of Life Science, Kyonggi University, Suwon, 16227, South Korea
| | - Sungho Ghil
- Department of Life Science, Kyonggi University, Suwon, 16227, South Korea.
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5
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Affiliation(s)
- Gibeom Kwon
- Department of Life Science, Kyonggi University
| | - Sungho Ghil
- Department of Life Science, Kyonggi University
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Kim K, Lee J, Ghil S. The regulators of G protein signaling
RGS
16 and
RGS
18 inhibit protease‐activated receptor 2/Gi/o signaling through distinct interactions with Gα in live cells. FEBS Lett 2018; 592:3126-3138. [DOI: 10.1002/1873-3468.13220] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 07/24/2018] [Accepted: 08/02/2018] [Indexed: 12/12/2022]
Affiliation(s)
- Kiman Kim
- Department of Life Science Kyonggi University Suwon Korea
| | - Jinyong Lee
- Department of Life Science Kyonggi University Suwon Korea
| | - Sungho Ghil
- Department of Life Science Kyonggi University Suwon Korea
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Kwon G, Ghil S. Identification of warm temperature acclimation-associated 65-kDa protein-2 in Kumgang fat minnow Rhynchocypris kumgangensis. J Exp Zool A Ecol Integr Physiol 2018. [PMID: 29542267 DOI: 10.1002/jez.2149] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Warm temperature acclimation-associated 65-kDa protein (Wap65) is known to respond to elevated water temperatures and the corresponding gene from several fish species has been cloned. Expression of Wap65 gene is induced by various physiological stresses, such as increase in water temperature, immune response and heavy metal exposure. Two isolated Wap65 genes, Wap65-1 and Wap65-2, display distinct tissue distribution and physiological functions despite high sequence homology. In a previous study, we identified the Wap65-1 gene (kmWap65-1) from Kumgang fat minnow, Rhynchocypris kumgangensis, a small freshwater fish endemic to Korea. The kmWap65-1 gene showed sequence homology with teleost Wap65-1 and mammalian hemopexin, and was highly expressed in response to increased water temperature and bacterial lipopolysaccharide (LPS) exposure. Here, we isolated kmWap65-2 from liver tissue of Kumgang fat minnow and compared the expression profiles of both kmWap65 genes following exposure to various physiological stresses, including thermal changes, bacterial challenge, and environmental toxins. Notably, while kmWap65-1 expression was significantly increased in response to high water temperature, LPS, cadmium, and iron, kmWap65-2 displayed no alterations in expression at high water temperature. However, kmWap65-2 expression was upregulated slightly in response to LPS and highly in presence of copper, bisphenol A, and estradiol. Based on the collective findings, we propose that kmWap65-1 and kmWap65-2 are multifunctional proteins with distinct functions that could serve as useful biomarkers for assessing physiological stress and associated responses in Kumgang fat minnow.
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Affiliation(s)
- Gibeom Kwon
- Department of Life Science, Kyonggi University, Suwon, Republic of Korea
| | - Sungho Ghil
- Department of Life Science, Kyonggi University, Suwon, Republic of Korea
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Ju H, Lee S, Lee J, Ghil S. Necdin modulates osteogenic cell differentiation by regulating Dlx5 and MAGE-D1. Biochem Biophys Res Commun 2017; 489:109-115. [PMID: 28528976 DOI: 10.1016/j.bbrc.2017.05.101] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 05/17/2017] [Indexed: 02/05/2023]
Abstract
Osteoblasts originate from mesenchymal stem cells that also differentiate into adipocytes, myoblasts, chondrocytes and fibroblasts. Osteogenic differentiation involves diverse regulatory proteins, including transcription and growth factors. Neurally differentiated embryonal carcinoma-derived protein (Necdin) has been identified as a key regulator of cell differentiation in various tissues, including neuronal, adipose, and muscular tissues; although its role in bone tissue remains to be established. Here, we investigated the potential involvement of Necdin in osteogenic differentiation. Our experiments revealed high expression of Necdin during osteoblast differentiation. Moreover, both transient and stable expression of Necdin induced osteoblast-specific markers in an osteogenic cell line through formation of a complex with melanoma-associated antigen D1 (MAGE-D1) and distal-less Homeobox 5 (Dlx5) and Runx2 promoter activation. Necdin expression was further associated with suppression of both cell proliferation and death in osteoblasts. Our results suggest that Necdin plays roles in cellular differentiation, proliferation and death in bone tissue.
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Affiliation(s)
- Hyunhee Ju
- Department of Life Science, Kyonggi University, Suwon 16227, Republic of Korea
| | - Sangho Lee
- Department of Life Science, Kyonggi University, Suwon 16227, Republic of Korea
| | - Jinyong Lee
- Department of Life Science, Kyonggi University, Suwon 16227, Republic of Korea
| | - Sungho Ghil
- Department of Life Science, Kyonggi University, Suwon 16227, Republic of Korea.
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Lee J, Ghil S. Regulator of G protein signaling 8 inhibits protease-activated receptor 1/G i/o signaling by forming a distinct G protein-dependent complex in live cells. Cell Signal 2016; 28:391-400. [DOI: 10.1016/j.cellsig.2016.01.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 01/27/2016] [Accepted: 01/28/2016] [Indexed: 10/22/2022]
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10
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Affiliation(s)
- Jisu Im
- Department of Life Science, Kyonggi University
| | | | - Sungho Ghil
- Department of Life Science, Kyonggi University
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Im J, Kwon G, Kong D, Ghil S. Identification of a warm-temperature acclimation-associated 65-kDa protein encoded by a temperature- and infection-responsive gene in the Kumgang fat minnow Rhynchocypris kumgangensis. ACTA ACUST UNITED AC 2015; 325:65-74. [PMID: 26612495 DOI: 10.1002/jez.1997] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 10/21/2015] [Accepted: 10/26/2015] [Indexed: 12/26/2022]
Abstract
Water temperature is one of the most important factors in fish physiology; thus, it is important to identify genes that respond to changes in water temperature. In this study, we identified a warm- temperature acclimation-associated 65-kDa protein (Wap65) in the Kumgang fat minnow Rhynchocypris kumgangensis, a small, cold-freshwater fish species endemic to Korea. Kumgang fat minnow Wap65-1 (kmWap65-1) was cloned using polymerase chain reaction (PCR)-based strategies, and was found to be highly homologous with teleost Wap65-1 and mammalian hemopexin, a heme-binding protein that transfers plasma heme into hepatocytes. kmWap65-1 mRNA was expressed mainly in the liver and its expression levels were significantly increased by both short- and long-term exposure to high temperature, which was evaluated by real-time quantitative PCR. Furthermore, the expression levels of kmWap65-1 were highly elevated by exposure to bacterial lipopolysaccharide. These results indicate that kmWap65-1 expression is associated with environmental stresses such as increases in water temperature and bacterial infection. J. Exp. Zool. 325A:65-74, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Jisu Im
- Department of Life Science, Kyonggi University, Suwon, Republic of Korea
| | - Gibeom Kwon
- Department of Life Science, Kyonggi University, Suwon, Republic of Korea
| | - Dongsoo Kong
- Department of Life Science, Kyonggi University, Suwon, Republic of Korea
| | - Sungho Ghil
- Department of Life Science, Kyonggi University, Suwon, Republic of Korea
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Abstract
Honeybees are among the most important pollinators in nature, and honeybee-associated products are useful in various areas, including the food industry. However, honeybees may be infected by various types of pathogens. The study of honeybee-associated diseases would greatly benefit from a successful cell culture system, but although some honeybee cell culture techniques have been introduced, these methods have not yet been fully established. Here, we describe a primary cell culture method for the honeybee, Apis mellifera. We isolated, sterilized, and seeded egg cells into non-coated cell culture dishes to generate cell aggregates. After approximately 10 d, aggregates were dissociated and seeded to cell culture dishes. Cell passages were continuously performed, with sub-culturing every 3-4 d. The cells expressed non-adherent phenotypes. Their growth increased with the passage number when they were cultured in growth medium based on L-15 insect medium but not Schneider's insect medium. Finally, polymerase chain reaction confirmed that the cells originated from A. mellifera. Our results suggest that the culturing methods described herein are appropriate for isolating primary cells from honeybee eggs. These methods could thus facilitate the study of honeybee-associated pathogenesis, development, and toxicology.
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Affiliation(s)
- Hyunhee Ju
- Department of Life Science, Kyonggi University, Suwon, 443-760, Republic of Korea
| | - Sungho Ghil
- Department of Life Science, Kyonggi University, Suwon, 443-760, Republic of Korea.
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Jung HW, Park I, Ghil S. Cannabinoid receptor activation inhibits cell cycle progression by modulating 14-3-3β. Cell Mol Biol Lett 2014; 19:347-60. [PMID: 25002257 PMCID: PMC6275927 DOI: 10.2478/s11658-014-0200-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 07/01/2014] [Indexed: 11/20/2022] Open
Abstract
Cannabinoids display various pharmacological activities, including tumor regression, anti-inflammatory and neuroprotective effects. To investigate the molecular mechanisms underlying the pharmacological effects of cannabinoids, we used a yeast two-hybrid system to screen a mouse brain cDNA library for proteins interacting with type 1 cannabinoid receptor (CB1R). Using the intracellular loop 3 of CB1R as bait, we identified 14-3-3β as an interacting partner of CB1R and confirmed their interaction using affinity-binding assays. 14-3-3β has been reported to induce a cell cycle delay at the G2/M phase. We tested the effects of cannabinoids on cell cycle progression in HeLa cells synchronized using a double-thymidine block-and-release protocol and found an increase in the population of G2/M phase cells. We further found that CB1R activation augmented the interaction of 14-3-3β with Wee1 and Cdc25B, and promoted phosphorylation of Cdc2 at Tyr-15. These results suggest that cannabinoids induce cell cycle delay at the G2/M phase by activating 14-3-3β.
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Affiliation(s)
- Hye-Won Jung
- Department of Life Science, Kyonggi University, Suwon, 443-760 Republic of Korea
| | - Inae Park
- Department of Life Science, Kyonggi University, Suwon, 443-760 Republic of Korea
| | - Sungho Ghil
- Department of Life Science, Kyonggi University, Suwon, 443-760 Republic of Korea
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14
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Ju H, Lee S, Kang S, Kim SS, Ghil S. The alpha subunit of Go modulates cell proliferation and differentiation through interactions with Necdin. Cell Commun Signal 2014; 12:39. [PMID: 25012566 PMCID: PMC4227020 DOI: 10.1186/s12964-014-0039-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 06/12/2014] [Indexed: 11/23/2022] Open
Abstract
Background Heterotrimeric GTP-binding proteins (G-proteins) play an important role in mediating signal transduction generated by neurotransmitters or hormones. Go, a member of the Gi/Go subfamily, is the most abundant G-protein found in the brain. Recently, the alpha subunit of Go (Gαo) was characterized as an inducer of neuronal differentiation. However, its underlying molecular mechanisms have remained unclear to date, since the downstream effectors of Gαo are ambiguous. Results A neurally differentiated embryonal carcinoma-derived protein (Necdin) was isolated as an interacting partner for Gαo from a mouse brain cDNA library using yeast two-hybrid screening. Interactions between the proteins were confirmed with several affinity binding assays, both in vitro and in vivo. Necdin interacted directly and preferentially with activated Gαo, compared to wild-type protein. Interestingly, Gαo did not interact with Gαi, despite high sequence homology between the two proteins. We subsequently analyzed whether Gαo modulates the cellular activities of Necdin. Notably, expression of Gαo significantly augmented Necdin-mediated cellular responses, such as proliferation and differentiation. Moreover, activation of type 1 cannabinoid receptor (CB1R), a Gi/oα-coupled receptor, augmented cell growth suppression, which was mediated by Gαo and Necdin in U87MG cells containing CB1R, Gαo, and Necdin as normal components. Conclusions These results collectively suggest that Necdin is a candidate downstream effector for Gαo. Our findings provide novel insights into the cellular roles of Gαo and its coupled receptor.
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15
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Ghil S, McCoy KL, Hepler JR. Regulator of G protein signaling 2 (RGS2) and RGS4 form distinct G protein-dependent complexes with protease activated-receptor 1 (PAR1) in live cells. PLoS One 2014; 9:e95355. [PMID: 24743392 PMCID: PMC3990635 DOI: 10.1371/journal.pone.0095355] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 03/26/2014] [Indexed: 12/03/2022] Open
Abstract
Protease-activated receptor 1 (PAR1) is a G-protein coupled receptor (GPCR) that is activated by natural proteases to regulate many physiological actions. We previously reported that PAR1 couples to Gi, Gq and G12 to activate linked signaling pathways. Regulators of G protein signaling (RGS) proteins serve as GTPase activating proteins to inhibit GPCR/G protein signaling. Some RGS proteins interact directly with certain GPCRs to modulate their signals, though cellular mechanisms dictating selective RGS/GPCR coupling are poorly understood. Here, using bioluminescence resonance energy transfer (BRET), we tested whether RGS2 and RGS4 bind to PAR1 in live COS-7 cells to regulate PAR1/Gα-mediated signaling. We report that PAR1 selectively interacts with either RGS2 or RGS4 in a G protein-dependent manner. Very little BRET activity is observed between PAR1-Venus (PAR1-Ven) and either RGS2-Luciferase (RGS2-Luc) or RGS4-Luc in the absence of Gα. However, in the presence of specific Gα subunits, BRET activity was markedly enhanced between PAR1-RGS2 by Gαq/11, and PAR1-RGS4 by Gαo, but not by other Gα subunits. Gαq/11-YFP/RGS2-Luc BRET activity is promoted by PAR1 and is markedly enhanced by agonist (TFLLR) stimulation. However, PAR1-Ven/RGS-Luc BRET activity was blocked by a PAR1 mutant (R205A) that eliminates PAR1-Gq/11 coupling. The purified intracellular third loop of PAR1 binds directly to purified His-RGS2 or His-RGS4. In cells, RGS2 and RGS4 inhibited PAR1/Gα-mediated calcium and MAPK/ERK signaling, respectively, but not RhoA signaling. Our findings indicate that RGS2 and RGS4 interact directly with PAR1 in Gα-dependent manner to modulate PAR1/Gα-mediated signaling, and highlight a cellular mechanism for selective GPCR/G protein/RGS coupling.
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Affiliation(s)
- Sungho Ghil
- Department of Life Science, Kyonggi University, Suwon, Republic of Korea
| | - Kelly L. McCoy
- Department of Pharmacology, Rollins Research center, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - John R. Hepler
- Department of Pharmacology, Rollins Research center, Emory University School of Medicine, Atlanta, Georgia, United States of America
- * E-mail:
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Ghil S, Choi JM, Kim SS, Lee YD, Liao Y, Birnbaumer L, Suh-Kim H. Compartmentalization of protein kinase A signaling by the heterotrimeric G protein Go. Proc Natl Acad Sci U S A 2006; 103:19158-63. [PMID: 17148597 PMCID: PMC1682014 DOI: 10.1073/pnas.0609392103] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
G(o), a member of the G(o/i) family, is the most abundant heterotrimeric G protein in brain. Most functions of G(o) are mediated by the G(betagamma) dimer; effector(s) for its alpha-subunit have not been clearly defined. Here we report that G(oalpha) interacts directly with cAMP-dependent protein kinase (PKA) through its GTPase domain. This interaction did not inhibit the kinase function of PKA but interfered with nuclear translocation of PKA while sparing its cytosolic function. This regulatory mechanism by which G(o) bifurcates PKA signaling may provide insights into how G(o) regulates complex processes such as neuritogenesis, synaptic plasticity, and cell transformation.
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Affiliation(s)
- Sungho Ghil
- Department of Biology, Kyonggi University, Suwon 442-760, South Korea
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