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Positive allosteric regulation of PAC1-R up-regulates PAC1-R and its specific ligand PACAP. Acta Biochim Biophys Sin (Shanghai) 2022; 54:657-672. [PMID: 35593471 PMCID: PMC9828401 DOI: 10.3724/abbs.2022041] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
PAC1-R is a recognized preferential receptor for the neuropeptide of pituitary adenylate cyclase-activating polypeptide (PACAP), which mediates neuroprotective and nerve regenerative activities of PACAP. In this study, we found that in both PAC1R-CHO cells with high expression of PAC1R-eGFP and retinal ganglion cells (RGC-5) with the natural expression of PAC1-R, oligo-peptide PACAP(28-38) and the positively charged arginine-rich penetrating peptide TAT, as positive allosteric modulators of PAC1-R, significantly trigger the nuclear translocation of PAC1-R. The chromatin immunoprecipitation (ChIP)-PCR results show that the nuclear translocated PAC1-R binds with the promoter regions of PAC1-R and its specific ligand PACAP. The up-regulated promoter activities of PAC1-R and PACAP induced by PACAP(28-38) or TAT are positively correlative with the increase of the expression levels of PAC1-R and PACAP. Moreover, the nuclear translocation of PAC1-R induced by PACAP(28-38) or TAT is significantly inhibited by the mutation of PAC1-R on Cys25 and the palmitoylation inhibitor 2-bromopalmitate. Meanwhile, the increase in both PAC1-R and PACAP levels and the neuroprotective activities of PACAP(28-38) and TAT in MPP-induced cell model of Parkinson ' s disease are synchronously inhibited by 2-bromopalmitate, which are positively correlated with the nuclear translocation of PAC1-R induced by PACAP(28-38) or TAT. Bioinformatics analysis and motif enrichment analysis following ChIP-sequencing show that the transcription factors including SP1, Zic2, GATA1, REST and YY1 may be recruited by nuclear PAC1-R and involved in regulating the promoter activities of PAC1-R and PACAP. ChIP-sequencing and related bioinformatics analysis show that the downstream target genes regulated by the nuclear PAC1-R are mostly involved in the process of cellular stress and related to neuroprotection, neuronal genesis and development.
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2
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Sukocheva OA, Hu DG, Meech R, Bishayee A. Divergence of Intracellular Trafficking of Sphingosine Kinase 1 and Sphingosine-1-Phosphate Receptor 3 in MCF-7 Breast Cancer Cells and MCF-7-Derived Stem Cell-Enriched Mammospheres. Int J Mol Sci 2021; 22:ijms22094314. [PMID: 33919234 PMCID: PMC8122545 DOI: 10.3390/ijms22094314] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 04/11/2021] [Accepted: 04/19/2021] [Indexed: 02/05/2023] Open
Abstract
Breast cancer MCF-7 cell-line-derived mammospheres were shown to be enriched in cells with a CD44+/CD24- surface profile, consistent with breast cancer stem cells (BCSC). These BCSC were previously reported to express key sphingolipid signaling effectors, including pro-oncogenic sphingosine kinase 1 (SphK1) and sphingosine-1-phosphate receptor 3 (S1P3). In this study, we explored intracellular trafficking and localization of SphK1 and S1P3 in parental MCF-7 cells, and MCF-7 derived BCSC-enriched mammospheres treated with growth- or apoptosis-stimulating agents. Intracellular trafficking and localization were assessed using confocal microscopy and cell fractionation, while CD44+/CD24- marker status was confirmed by flow cytometry. Mammospheres expressed significantly higher levels of S1P3 compared to parental MCF-7 cells (p < 0.01). Growth-promoting agents (S1P and estrogen) induced SphK1 and S1P3 translocation from cytoplasm to nuclei, which may facilitate the involvement of SphK1 and S1P3 in gene regulation. In contrast, pro-apoptotic cytokine tumor necrosis factor α (TNFα)-treated MCF-7 cells demonstrated increased apoptosis and no nuclear localization of SphK1 and S1P3, suggesting that TNFα can inhibit nuclear translocation of SphK1 and S1P3. TNFα inhibited mammosphere formation and induced S1P3 internalization and degradation. No nuclear translocation of S1P3 was detected in TNFα-stimulated mammospheres. Notably, SphK1 and S1P3 expression and localization were highly heterogenous in mammospheres, suggesting the potential for a large variety of responses. The findings provide further insights into the understanding of sphingolipid signaling and intracellular trafficking in BCs. Our data indicates that the inhibition of SphK1 and S1P3 nuclear translocation represents a novel method to prevent BCSCs proliferation.
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Affiliation(s)
- Olga A. Sukocheva
- Discipline of Health Sciences, College of Nursing and Health Sciences, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia
- Correspondence: (O.A.S.); or (A.B.)
| | - Dong Gui Hu
- Department of Clinical Pharmacology, College of Medicine and Public Health, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia; (D.G.H.); (R.M.)
| | - Robyn Meech
- Department of Clinical Pharmacology, College of Medicine and Public Health, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia; (D.G.H.); (R.M.)
| | - Anupam Bishayee
- Lake Erie College of Osteopathic Medicine, Bradenton, FL 34211, USA
- Correspondence: (O.A.S.); or (A.B.)
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3
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Mohammad Nezhady MA, Rivera JC, Chemtob S. Location Bias as Emerging Paradigm in GPCR Biology and Drug Discovery. iScience 2020; 23:101643. [PMID: 33103080 PMCID: PMC7569339 DOI: 10.1016/j.isci.2020.101643] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
GPCRs are the largest receptor family that are involved in virtually all biological processes. Pharmacologically, they are highly druggable targets, as they cover more than 40% of all drugs in the market. Our knowledge of biased signaling provided insight into pharmacology vastly improving drug design to avoid unwanted effects and achieve higher efficacy and selectivity. However, yet another feature of GPCR biology is left largely unexplored, location bias. Recent developments in this field show promising avenues for evolution of new class of pharmaceuticals with greater potential for higher level of precision medicine. Further consideration and understanding of this phenomenon with deep biochemical and molecular insights would pave the road to success. In this review, we critically analyze this perspective and discuss new avenues of investigation.
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Affiliation(s)
- Mohammad Ali Mohammad Nezhady
- Programmes en Biologie Moléculaire, Faculté de Médecine, Université de Montréal, Montreal, QC, Canada
- Centre de Recherche du CHU Sainte-Justine, Montreal, QC H3T 1C5, Canada
- Corresponding author
| | | | - Sylvain Chemtob
- Programmes en Biologie Moléculaire, Faculté de Médecine, Université de Montréal, Montreal, QC, Canada
- Centre de Recherche du CHU Sainte-Justine, Montreal, QC H3T 1C5, Canada
- Maisonneuve-Rosemont Hospital Research Centre, Montreal, QC, Canada
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4
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Zhang X, Fan S, Zhang L, Shi Y. Glucagon-like peptide-1 receptor undergoes importin-α-dependent nuclear localization in rat aortic smooth muscle cells. FEBS Lett 2020; 594:1506-1516. [PMID: 32010959 DOI: 10.1002/1873-3468.13751] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 01/21/2020] [Accepted: 01/29/2020] [Indexed: 11/08/2022]
Abstract
Glucagon-like peptide 1 receptor (GLP-1R) belongs to the family B of G protein-coupled receptors (GPCRs) and has antidiabetic and cardioprotective effects. Classical GLP-1R at the plasma membrane undergoes desensitization and internalization and is recycled back to the plasma membrane under the control of GLP-1 in islet β-cells. However, the subcellular localization of GLP-1R in the vascular system remains unclear. Here, we find that GLP-1R is localized in the nucleus of rat aortic smooth muscle cells (RASMCs) and in the tunica media. We identify a functional nuclear localization signal (NLS; 412-442aa) at the C-terminal region of GLP-1R. Nuclear import of GLP-1R is mediated by an importin-α-dependent pathway and regulated by phosphorylation of Ser416 in the NLS. Upon leaving the nucleus, GLP-1R promotes cell proliferation in RASMCs. These findings may provide insights into the cardiovascular functions of GLP-1R.
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Affiliation(s)
- Xin Zhang
- Key Laboratory of Chemical Biology and Molecular Engineering, Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan, China
| | - Shaohua Fan
- Key Laboratory of Chemical Biology and Molecular Engineering, Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan, China
| | - Lihui Zhang
- Shanxi Bethune Hospital, Taiyuan, Shanxi, China
| | - Yawei Shi
- Key Laboratory of Chemical Biology and Molecular Engineering, Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan, China
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5
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Abstract
As basic research into GPCR signaling and its association with disease has come into fruition, greater clarity has emerged with regards to how these receptors may be amenable to therapeutic intervention. As a diverse group of receptor proteins, which regulate a variety of intracellular signaling pathways, research in this area has been slow to yield tangible therapeutic agents for the treatment of a number of diseases including cancer. However, recently such research has gained momentum based on a series of studies that have sought to define GPCR proteins dynamics through the elucidation of their crystal structures. In this chapter, we define the approaches that have been adopted in developing better therapeutics directed against the specific parts of the receptor proteins, such as the extracellular and the intracellular domains, including the ligands and auxiliary proteins that bind them. Finally, we also briefly outline how GPCR-derived signaling transduction pathways hold great potential as additional targets.
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Affiliation(s)
- Surinder M Soond
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russian Federation.
| | - Andrey A Zamyatnin
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russian Federation; Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation.
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6
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Aouiss A, Anka Idrissi D, Kabine M, Zaid Y. Update of inflammatory proliferative retinopathy: Ischemia, hypoxia and angiogenesis. Curr Res Transl Med 2019; 67:62-71. [PMID: 30685380 DOI: 10.1016/j.retram.2019.01.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 12/19/2018] [Accepted: 01/16/2019] [Indexed: 02/06/2023]
Abstract
Diabetic retinopathy (DR) and retinopathy of prematurity (ROP) present two examples of proliferative retinopathy, characterized by the same stages of progression; ischemia of the retinal vessels, leads to hypoxia and to correct the problem there is the setting up of uncontrolled angiogenesis, which subsequently causes blindness or even detachment of the retina. The difference is the following; that DR initiated by the metabolic complications that are due to hyperglycemia, and ROP is induced by overexposure of the neonatal retina to oxygen. In this review, we will demonstrate the physiopathological mechanism of the two forms of proliferative retinopathy DR and ROP, in particular the role of the CD40/CD40L axis and IL-1 on vascular complications and onset of inflammation of the retina, the implications of their effects on the onset of pathogenic angiogenesis, thus understanding the link between platelets and retinal ischemia. In addition, what are the therapeutic targets that could slow its progression?
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Affiliation(s)
- A Aouiss
- Laboratory of Health and Environment, Department of Biology, Faculty of Sciences Ain Chock, University of Hassan II, Casablanca, Morocco.
| | - D Anka Idrissi
- Laboratory of Health and Environment, Department of Biology, Faculty of Sciences Ain Chock, University of Hassan II, Casablanca, Morocco
| | - M Kabine
- Laboratory of Health and Environment, Department of Biology, Faculty of Sciences Ain Chock, University of Hassan II, Casablanca, Morocco
| | - Y Zaid
- Laboratory of Thrombosis and Hemostasis, Montreal Heart Institute, Montreal, H1T1C8, Quebec, Canada
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7
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Abstract
The trillions of synaptic connections within the human brain are shaped by experience and neuronal activity, both of which underlie synaptic plasticity and ultimately learning and memory. G protein-coupled receptors (GPCRs) play key roles in synaptic plasticity by strengthening or weakening synapses and/or shaping dendritic spines. While most studies of synaptic plasticity have focused on cell surface receptors and their downstream signaling partners, emerging data point to a critical new role for the very same receptors to signal from inside the cell. Intracellular receptors have been localized to the nucleus, endoplasmic reticulum, lysosome, and mitochondria. From these intracellular positions, such receptors may couple to different signaling systems, display unique desensitization patterns, and/or show distinct patterns of subcellular distribution. Intracellular GPCRs can be activated at the cell surface, endocytosed, and transported to an intracellular site or simply activated in situ by de novo ligand synthesis, diffusion of permeable ligands, or active transport of non-permeable ligands. Current findings reinforce the notion that intracellular GPCRs play a dynamic role in synaptic plasticity and learning and memory. As new intracellular GPCR roles are defined, the need to selectively tailor agonists and/or antagonists to both intracellular and cell surface receptors may lead to the development of more effective therapeutic tools.
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Affiliation(s)
- Yuh-Jiin I. Jong
- Department of Neuroscience, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Steven K. Harmon
- Department of Neuroscience, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Karen L. O’Malley
- Department of Neuroscience, Washington University School of Medicine, Saint Louis, MO 63110, USA
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8
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Dubuc C, Savard M, Bovenzi V, Lessard A, Côté J, Neugebauer W, Geha S, Chemtob S, Gobeil F. Antitumor activity of cell-penetrant kinin B1 receptor antagonists in human triple-negative breast cancer cells. J Cell Physiol 2018; 234:2851-2865. [PMID: 30132865 DOI: 10.1002/jcp.27103] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 06/28/2018] [Indexed: 12/26/2022]
Abstract
High nuclear expression of G protein-coupled receptors, including kinin B1 receptors (B1R), has been observed in several human cancers, but the clinical significance of this is unknown. We put forward the hypothesis that these "nuclearized" kinin B1R contribute to tumorigenicity and can be a new target in anticancer strategies. Our initial immunostaining and ultrastructural electron microscopy analyses demonstrated high B1R expression predominantly located at internal/nuclear compartments in the MDA-MB-231 triple-negative breast cancer (TNBC) cell line as well as in clinical samples of patients with TNBC. On the basis of these findings, in the present study, we evaluated the anticancer therapeutic potential of newly identified, cell-permeable B1R antagonists in MDA-MB-231 cells (ligand-receptor binding/activity assays and LC-MS/MS analyses). We found that these compounds (SSR240612, NG67, and N2000) were more toxic to MDA-MB-231 cells in comparison with low- or non-B1R expressing MCF-10A normal human mammary epithelial cells and COS-1 cells, respectively (clonogenic, MTT proliferative/cytocidal assays, and fluorescence-activated cell-sorting (FACS)-based apoptosis analyses). By comparison, the peptide B1R antagonist R954 unable to cross cell membrane failed to produce anticancer effects. Furthermore, the putative mechanisms underlying the anticancer activities of cell-penetrant B1R antagonists were assessed by analyzing cell cycle regulation and signaling molecules related to cell survival and apoptosis (FACS and western blot). Finally, drug combination experiments showed that cell-penetrant B1R antagonists can cooperate with suboptimal doses of chemotherapeutic agents (doxorubicin and paclitaxel) to promote TNBC death. This study provides evidence on the potential value of internally acting kinin B1R antagonists in averting growth of breast cancer.
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Affiliation(s)
- Céléna Dubuc
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
- Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Martin Savard
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
- Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Veronica Bovenzi
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
- Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Andrée Lessard
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland
| | - Jérôme Côté
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
- Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Witold Neugebauer
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
- Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Sameh Geha
- Department of Pathology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Québec, Canada
| | - Sylvain Chemtob
- Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Montréal, Québec, Canada
| | - Fernand Gobeil
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
- Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
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9
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Pupo M, Bodmer A, Berto M, Maggiolini M, Dietrich PY, Picard D. A genetic polymorphism repurposes the G-protein coupled and membrane-associated estrogen receptor GPER to a transcription factor-like molecule promoting paracrine signaling between stroma and breast carcinoma cells. Oncotarget 2018; 8:46728-46744. [PMID: 28596490 PMCID: PMC5564519 DOI: 10.18632/oncotarget.18156] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 05/10/2017] [Indexed: 01/08/2023] Open
Abstract
GPER is a membrane-associated estrogen receptor of the family of G-protein coupled receptors. For breast cancer, the contribution of GPER to promoting the proliferation and migration of both carcinoma cells and cancer-associated fibroblasts (CAFs) in response to estrogen and other agonists has extensively been investigated. Intriguingly, GPER was previously found to be localized to the nucleus in one isolate of breast CAFs. Moreover, this nuclear GPER was shown to bind regulatory sequences of cancer-relevant target genes and to induce their expression. We decided to find out what induces the nuclear localization of GPER, how general this phenomenon is, and what its functional significance is. We discovered that interfering with N-linked glycosylation of GPER, either by mutation of the predicted glycosylation sites or pharmacologically with tunicamycin, drives GPER into the nucleus. Surveying a small set of CAFs from breast cancer biopsies, we found that a relatively common single nucleotide polymorphism, which results in the expression of a GPER variant with the amino acid substitution P16L, is associated with the nuclear localization of GPER. GPER with P16L fails to be glycosylated, presumably because of a conformational effect on the nearby glycosylation sites. GPER P16L is defective for membrane-associated signaling, but instead acts like an estrogen-stimulated transcription factor. In CAFs, it induces the secretion of paracrine factors that promote the migration of carcinoma cells. This raises the possibility that the GPER P16L polymorphism could be a risk factor for breast cancer.
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Affiliation(s)
- Marco Pupo
- Département de Biologie Cellulaire and Institute of Genetics and Genomics of Geneva, Université de Genève, Sciences III, CH-1211 Genève 4, Switzerland.,Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, Italy.,Current address: Areta International S.r.l., Gerenzano, Italy
| | - Alexandre Bodmer
- Département d'Oncologie, Hôpitaux Universitaires de Genève, CH - 1211 Genève 14, Switzerland
| | - Melissa Berto
- Département de Biologie Cellulaire and Institute of Genetics and Genomics of Geneva, Université de Genève, Sciences III, CH-1211 Genève 4, Switzerland
| | - Marcello Maggiolini
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, Italy
| | - Pierre-Yves Dietrich
- Département d'Oncologie, Hôpitaux Universitaires de Genève, CH - 1211 Genève 14, Switzerland
| | - Didier Picard
- Département de Biologie Cellulaire and Institute of Genetics and Genomics of Geneva, Université de Genève, Sciences III, CH-1211 Genève 4, Switzerland
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10
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Wang W, Qiao Y, Li Z. New Insights into Modes of GPCR Activation. Trends Pharmacol Sci 2018; 39:367-386. [DOI: 10.1016/j.tips.2018.01.001] [Citation(s) in RCA: 129] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 01/03/2018] [Accepted: 01/08/2018] [Indexed: 12/22/2022]
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11
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Rahman MM, Hazan A, Selway JL, Herath DS, Harwood CA, Pirzado MS, Atkar R, Kelsell DP, Linton KJ, Philpott MP, Neill GW. A Novel Mechanism for Activation of GLI1 by Nuclear SMO That Escapes Anti-SMO Inhibitors. Cancer Res 2018; 78:2577-2588. [DOI: 10.1158/0008-5472.can-17-2897] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 12/10/2017] [Accepted: 02/16/2018] [Indexed: 11/16/2022]
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12
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Sukocheva OA. Expansion of Sphingosine Kinase and Sphingosine-1-Phosphate Receptor Function in Normal and Cancer Cells: From Membrane Restructuring to Mediation of Estrogen Signaling and Stem Cell Programming. Int J Mol Sci 2018; 19:ijms19020420. [PMID: 29385066 PMCID: PMC5855642 DOI: 10.3390/ijms19020420] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 01/21/2018] [Accepted: 01/24/2018] [Indexed: 02/05/2023] Open
Abstract
Sphingolipids, sphingolipid metabolizing enzymes, and their receptors network are being recognized as part of the signaling mechanisms, which govern breast cancer cell growth, migration, and survival during chemotherapy treatment. Approximately 70% of breast cancers are estrogen receptor (ER) positive and, thus, rely on estrogen signaling. Estrogen activates an intracellular network composed of many cytoplasmic and nuclear mediators. Some estrogen effects can be mediated by sphingolipids. Estrogen activates sphingosine kinase 1 (SphK1) and amplifies the intracellular concentration of sphingosine-1-phosphate (S1P) in breast cancer cells during stimulation of proliferation and survival. Specifically, Estrogen activates S1P receptors (S1PR) and induces growth factor receptor transactivation. SphK, S1P, and S1PR expression are causally associated with endocrine resistance and progression to advanced tumor stages in ER-positive breast cancers in vivo. Recently, the network of SphK/S1PR was shown to promote the development of ER-negative cancers and breast cancer stem cells, as well as stimulating angiogenesis. Novel findings confirm and broaden our knowledge about the cross-talk between sphingolipids and estrogen network in normal and malignant cells. Current S1PRs therapeutic inhibition was indicated as a promising chemotherapy approach in non-responsive and advanced malignancies. Considering that sphingolipid signaling has a prominent role in terminally differentiated cells, the impact should be considered when designing specific SphK/S1PR inhibitors. This study analyzes the dynamic of the transformation of sphingolipid axis during a transition from normal to pathological condition on the level of the whole organism. The sphingolipid-based mediation and facilitation of global effects of estrogen were critically accented as a bridging mechanism that should be explored in cancer prevention.
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Affiliation(s)
- Olga A Sukocheva
- College of Nursing and Health Sciences, Flinders University of South Australia, Bedford Park, SA 5042, Australia.
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13
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Dubuc C, Savard M, Bovenzi V, Lessard A, Fortier A, Côté J, Neugebauer W, Rizzolio F, Geha S, Giordano A, Chemtob S, Gobeil F. Targeting intracellular B2 receptors using novel cell-penetrating antagonists to arrest growth and induce apoptosis in human triple-negative breast cancer. Oncotarget 2018. [PMID: 29515778 PMCID: PMC5839409 DOI: 10.18632/oncotarget.24009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
G protein-coupled receptors (GPCRs) are integral cell-surface proteins having a central role in tumor growth and metastasis. However, several GPCRs retain an atypical intracellular/nuclear location in various types of cancer. The pathological significance of this is currently unknown. Here we extend this observation by showing that the bradykinin B2R (BK-B2R) is nuclearly expressed in the human triple-negative breast cancer (TNBC) cell line MDA-MB-231 and in human clinical specimens of TNBC. We posited that these “nuclearized” receptors could be involved in oncogenic signaling linked to aberrant growth and survival maintenance of TNBC. We used cell-penetrating BK-B2R antagonists, including FR173657 and novel transducible, cell-permeable forms of the peptide B2R antagonist HOE 140 (NG68, NG134) to demonstrate their superior efficacy over impermeable ones (HOE 140), in blocking proliferation and promoting apoptosis of MDA-MB-231 cells. Some showed an even greater antineoplastic activity over conventional chemotherapeutic drugs in vitro. The cell-permeable B2R antagonists had less to no anticancer effects on B2R shRNA-knockdown or non-B2R expressing (COS-1) cells, indicating specificity in their action. Possible mechanisms of their anticancer effects may involve activation of p38kinase/p27Kip1 pathways. Together, our data support the existence of a possible intracrine signaling pathway via internal/nuclear B2R, critical for the growth of TNBC cells, and identify new chemical entities that enable to target the corresponding intracellular GPCRs.
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Affiliation(s)
- Céléna Dubuc
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada.,Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Martin Savard
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada.,Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Veronica Bovenzi
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada.,Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Andrée Lessard
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Audrey Fortier
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada.,Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Jérôme Côté
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada.,Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Witold Neugebauer
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada.,Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Flavio Rizzolio
- Department of Biology, Sbarro Institute for Cancer Research and Molecular Medicine, Temple University, Philadelphia, PA, USA.,Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca' Foscari Venezia, Mestre-Venezia, Italy
| | - Sameh Geha
- Department of Pathology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Québec, Canada
| | - Antonio Giordano
- Department of Biology, Sbarro Institute for Cancer Research and Molecular Medicine, Temple University, Philadelphia, PA, USA
| | - Sylvain Chemtob
- Department of Pediatrics, Centre Hospitalier Universitaire Sainte-Justine Research Center, Montréal, Québec, Canada
| | - Fernand Gobeil
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada.,Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
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14
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Joyal JS, Gantner ML, Smith LEH. Retinal energy demands control vascular supply of the retina in development and disease: The role of neuronal lipid and glucose metabolism. Prog Retin Eye Res 2017; 64:131-156. [PMID: 29175509 DOI: 10.1016/j.preteyeres.2017.11.002] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 11/11/2017] [Accepted: 11/15/2017] [Indexed: 12/15/2022]
Affiliation(s)
- Jean-Sébastien Joyal
- Department of Pediatrics, Pharmacology and Ophthalmology, CHU Sainte-Justine Research Center, Université de Montréal, Montreal, Qc, Canada; Department of Pharmacology and Therapeutics, McGill University, Montreal, Qc, Canada.
| | - Marin L Gantner
- The Lowy Medical Research Institute, La Jolla, United States
| | - Lois E H Smith
- Department of Ophthalmology, Harvard Medical School, Boston Children's Hospital, 300 Longwood Avenue, Boston MA 02115, United States.
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15
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Jong YJI, Harmon SK, O'Malley KL. GPCR signalling from within the cell. Br J Pharmacol 2017; 175:4026-4035. [PMID: 28872669 DOI: 10.1111/bph.14023] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 08/08/2017] [Accepted: 08/17/2017] [Indexed: 12/22/2022] Open
Abstract
Traditionally, signal transduction from GPCRs is thought to emanate from the cell surface where receptor interactions with external stimuli can be transformed into a broad range of cellular responses. However, emergent data show that numerous GPCRs are also associated with various intracellular membranes where they may couple to different signalling systems, display unique desensitization patterns and/or exhibit distinct patterns of subcellular distribution. Although many GPCRs can be activated at the cell surface and subsequently endocytosed and transported to a unique intracellular site, other intracellular GPCRs can be activated in situ either via de novo ligand synthesis, diffusion of permeable ligands or active transport of nonpermeable ligands. Current findings reinforce the notion that intracellular GPCRs play a dynamic role in various biological functions including learning and memory, contractility and angiogenesis. As new intracellular GPCR roles are defined, the need to selectively tailor agonists and/or antagonists to both intracellular and cell surface receptors may lead to the development of more effective therapeutic tools. LINKED ARTICLES This article is part of a themed section on Molecular Pharmacology of GPCRs. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.21/issuetoc.
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Affiliation(s)
- Yuh-Jiin I Jong
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
| | - Steven K Harmon
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
| | - Karen L O'Malley
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
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16
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Patmanathan SN, Wang W, Yap LF, Herr DR, Paterson IC. Mechanisms of sphingosine 1-phosphate receptor signalling in cancer. Cell Signal 2017; 34:66-75. [PMID: 28302566 DOI: 10.1016/j.cellsig.2017.03.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 03/11/2017] [Accepted: 03/11/2017] [Indexed: 12/12/2022]
Abstract
S1P is a small bioactive lipid which exerts its effects following binding to a family of five G protein-coupled receptors, known as S1P1-5. Following receptor activation, multiple signalling cascades are activated, allowing S1P to regulate a range of cellular processes, such as proliferation, apoptosis, migration and angiogenesis. There is strong evidence implicating the involvement of S1P receptors (S1PRs) in cancer progression and the oncogenic effects of S1P can result from alterations in the expression of one or more of the S1PRs and/or the enzymes that regulate the levels of S1P. However, cooperativity between the individual S1PRs, functional interactions with receptor tyrosine kinases and the sub-cellular localisation of the S1PRs within tumour cells also appear to play a role in mediating the effects of S1PR signalling during carcinogenesis. Here we review what is known regarding the role of individual S1PRs in cancer and discuss the recent evidence to suggest cross-talk between the S1PRs and other cellular signalling pathways in cancer. We will also discuss the therapeutic potential of targeting the S1PRs and their downstream signalling pathways for the treatment of cancer.
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Affiliation(s)
- Sathya Narayanan Patmanathan
- Department of Oral and Craniofacial Sciences, Oral Cancer Research & Coordinating Centre, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Wei Wang
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore
| | - Lee Fah Yap
- Department of Oral and Craniofacial Sciences, Oral Cancer Research & Coordinating Centre, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Deron R Herr
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore
| | - Ian C Paterson
- Department of Oral and Craniofacial Sciences, Oral Cancer Research & Coordinating Centre, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia.
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17
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Bhosle VK, Rivera JC, Chemtob S. New insights into mechanisms of nuclear translocation of G-protein coupled receptors. Small GTPases 2017; 10:254-263. [PMID: 28125336 DOI: 10.1080/21541248.2017.1282402] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The G-protein coupled receptor (GPCR) signaling was long believed to involve activation of receptor exclusively at the cell surface, followed by its binding to heterotrimeric G-proteins and arrestins to trigger various intracellular signaling cascades, and termination of signaling by internalization of the receptor. It is now accepted that many GPCRs continue to signal after internalization in the endosomes. Since the breakthrough discoveries of nuclear binding sites for their ligands in 1980s, several GPCRs have been detected at cell nuclei. But mechanisms of nuclear localization of GPCRs, many of whom contain putative nuclear localization signals, remain poorly understood to date. Nevertheless, it is known that subcellular trafficking of GPCRs is regulated by members of Ras superfamily of small GTPases, most notably by Rab and Arf GTPases. In this commentary, we highlight several recent studies which suggest novel roles of small GTPases, importins and sorting nexin proteins in the nuclear translocation of GPCRs via vesicular transport pathways. Taken together with increasing evidence for in vivo functionality of the nuclear GPCRs, better understanding of their trafficking will provide valuable clues in cell biology.
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Affiliation(s)
- Vikrant K Bhosle
- a Department of Pharmacology and Therapeutics , McGill University , Montréal , Québec , Canada.,b CHU Sainte-Justine Hospital Research Centre , University of Montréal , Montréal , Québec , Canada.,c Maisonneuve-Rosemont Hospital Research Centre , University of Montréal , Montréal , Québec , Canada.,e Cell Biology Program , Peter Gilgan Centre for Research and Learning , Toronto , Ontario , Canada
| | - José Carlos Rivera
- b CHU Sainte-Justine Hospital Research Centre , University of Montréal , Montréal , Québec , Canada.,c Maisonneuve-Rosemont Hospital Research Centre , University of Montréal , Montréal , Québec , Canada
| | - Sylvain Chemtob
- a Department of Pharmacology and Therapeutics , McGill University , Montréal , Québec , Canada.,b CHU Sainte-Justine Hospital Research Centre , University of Montréal , Montréal , Québec , Canada.,c Maisonneuve-Rosemont Hospital Research Centre , University of Montréal , Montréal , Québec , Canada.,d Departments of Pediatrics, Ophthalmology and Pharmacology , University of Montréal , Montréal , Québec , Canada
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18
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Wierzbicka JM, Żmijewski MA, Antoniewicz J, Sobjanek M, Slominski AT. Differentiation of Keratinocytes Modulates Skin HPA Analog. J Cell Physiol 2016; 232:154-66. [PMID: 27061711 DOI: 10.1002/jcp.25400] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Accepted: 04/04/2016] [Indexed: 12/16/2022]
Abstract
It is well established, that epidermal keratinocytes express functional equivalent of hypothalamus-pituitary-adrenal axis (HPA) in order to respond to changing environment and maintain internal homeostasis. We are presenting data indicating that differentiation of primary neonatal human keratinocytes (HPEKp), induced by prolonged incubation or calcium is accompanied by significant changes in the expression of the elements of skin analog of HPA (sHPA). Expression of CRF, UCN1-3, POMC, ACTH, CRFR1, CRFR2, MC1R, MC2R, and GR (coded by NR3C1 gene) were observed on gene/protein levels along differentiation of keratinocytes in culture with similar pattern seen by immunohistochemistry on full thickness skin biopsies. Expression of CRF was more pronounced in less differentiated keratinocytes, which corresponded to the detection of CRF immunoreactivity preferentially in the stratum basale. POMC expression was enhanced in more differentiated keratinocytes, which corresponded to detection of ACTH immunoreactivity, predominantly in the stratum spinosum and stratum granulosum. Expression of urocortins was also affected by induction of HPEKp differentiation. Immunohistochemical studies showed high prevalence of CRFR1 in well differentiated keratinocytes, while smaller keratinocytes showed predominantly CRFR2 immunoreactivity. MC2R mRNA levels were elevated from days 4 to 8 of in vitro incubation, while MC2R immunoreactivity was the highest in the upper layers of epidermis. Similar changes in mRNA/protein levels of sHPA elements were observed in HPEKp keratinocytes treated with calcium. Summarizing, preferential expression of CRF and POMC (ACTH) by populations of keratinocytes on different stage of differentiation resembles organization of central HPA axis suggesting their distinct role in physiology and pathology of the epidermis. J. Cell. Physiol. 232: 154-166, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
| | | | - Jakub Antoniewicz
- Department of Histology, Medical University of Gdańsk, Gdańsk, Poland
| | - Michal Sobjanek
- Department of Dermatology, Venereology and Allergology, Medical University of Gdańsk, Gdańsk, Poland
| | - Andrzej T Slominski
- Department of Dermatology, University of Alabama Birmingham, Birmingham, Alabama.,VA Medical Center, Birmingham, Alabama
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19
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Bhosle VK, Rivera JC, Zhou TE, Omri S, Sanchez M, Hamel D, Zhu T, Rouget R, Rabea AA, Hou X, Lahaie I, Ribeiro-da-Silva A, Chemtob S. Nuclear localization of platelet-activating factor receptor controls retinal neovascularization. Cell Discov 2016; 2:16017. [PMID: 27462464 PMCID: PMC4941644 DOI: 10.1038/celldisc.2016.17] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 05/11/2016] [Indexed: 02/08/2023] Open
Abstract
Platelet-activating factor (PAF) is a pleiotropic phospholipid with proinflammatory, procoagulant and angiogenic actions on the vasculature. We and others have reported the presence of PAF receptor (Ptafr) at intracellular sites such as the nucleus. However, mechanisms of localization and physiologic functions of intracellular Ptafr remain poorly understood. We hereby identify the importance of C-terminal motif of the receptor and uncover novel roles of Rab11a GTPase and importin-5 in nuclear translocation of Ptafr in primary human retinal microvascular endothelial cells. Nuclear localization of Ptafr is independent of exogenous PAF stimulation as well as intracellular PAF biosynthesis. Moreover, nuclear Ptafr is responsible for the upregulation of unique set of growth factors, including vascular endothelial growth factor, in vitro and ex vivo. We further corroborate the intracrine PAF signaling, resulting in angiogenesis in vivo, using Ptafr antagonists with distinct plasma membrane permeability. Collectively, our findings show that nuclear Ptafr translocates in an agonist-independent manner, and distinctive functions of Ptafr based on its cellular localization point to another dimension needed for pharmacologic selectivity of drugs.
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Affiliation(s)
- Vikrant K Bhosle
- Department of Pharmacology and Therapeutics, McGill University, Montréal, QC, Canada; CHU Sainte Justine Hospital Research Centre, University of Montréal, Montréal, QC, Canada; Department of Ophthalmology, Research Centre of Hôpital Maisonneuve-Rosemont, University of Montréal, Montréal, QC, Canada
| | - José Carlos Rivera
- CHU Sainte Justine Hospital Research Centre, University of Montréal, Montréal, QC, Canada; Department of Ophthalmology, Research Centre of Hôpital Maisonneuve-Rosemont, University of Montréal, Montréal, QC, Canada
| | - Tianwei Ellen Zhou
- Department of Pharmacology and Therapeutics, McGill University, Montréal, QC, Canada; CHU Sainte Justine Hospital Research Centre, University of Montréal, Montréal, QC, Canada; Department of Ophthalmology, Research Centre of Hôpital Maisonneuve-Rosemont, University of Montréal, Montréal, QC, Canada; Department of Medicine, McGill University Health Center, Montreal, QC, Canada
| | - Samy Omri
- CHU Sainte Justine Hospital Research Centre, University of Montréal, Montréal, QC, Canada; Department of Ophthalmology, Research Centre of Hôpital Maisonneuve-Rosemont, University of Montréal, Montréal, QC, Canada
| | - Melanie Sanchez
- Department of Pharmacology and Therapeutics, McGill University, Montréal, QC, Canada; CHU Sainte Justine Hospital Research Centre, University of Montréal, Montréal, QC, Canada; Department of Ophthalmology, Research Centre of Hôpital Maisonneuve-Rosemont, University of Montréal, Montréal, QC, Canada
| | - David Hamel
- CHU Sainte Justine Hospital Research Centre, University of Montréal, Montréal, QC, Canada; Department of Pharmacology, University of Montréal, Montréal, QC, Canada
| | - Tang Zhu
- CHU Sainte Justine Hospital Research Centre, University of Montréal , Montréal, QC, Canada
| | - Raphael Rouget
- Department of Pharmacology and Therapeutics, McGill University, Montréal, QC, Canada; CHU Sainte Justine Hospital Research Centre, University of Montréal, Montréal, QC, Canada
| | - Areej Al Rabea
- Experimental Surgery, Montreal General Hospital, McGill University , Montréal, QC, Canada
| | - Xin Hou
- CHU Sainte Justine Hospital Research Centre, University of Montréal , Montréal, QC, Canada
| | - Isabelle Lahaie
- CHU Sainte Justine Hospital Research Centre, University of Montréal, Montréal, QC, Canada; Department of Ophthalmology, Research Centre of Hôpital Maisonneuve-Rosemont, University of Montréal, Montréal, QC, Canada
| | - Alfredo Ribeiro-da-Silva
- Department of Pharmacology and Therapeutics, McGill University, Montréal, QC, Canada; Alan Edwards Centre for Research on Pain, McGill University, Montréal, QC, Canada; Department of Anatomy and Cell Biology, McGill University, Montréal, QC, Canada
| | - Sylvain Chemtob
- Department of Pharmacology and Therapeutics, McGill University, Montréal, QC, Canada; CHU Sainte Justine Hospital Research Centre, University of Montréal, Montréal, QC, Canada; Department of Ophthalmology, Research Centre of Hôpital Maisonneuve-Rosemont, University of Montréal, Montréal, QC, Canada; Department of Pharmacology, University of Montréal, Montréal, QC, Canada; Departments of Pediatrics and Ophthalmology, Faculty of Medicine, University of Montréal, Montréal, QC, Canada
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20
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Regna K, Kurshan PT, Harwood BN, Jenkins AM, Lai CQ, Muskavitch MAT, Kopin AS, Draper I. A critical role for the Drosophila dopamine D1-like receptor Dop1R2 at the onset of metamorphosis. BMC DEVELOPMENTAL BIOLOGY 2016; 16:15. [PMID: 27184815 PMCID: PMC4868058 DOI: 10.1186/s12861-016-0115-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 05/08/2016] [Indexed: 01/26/2023]
Abstract
BACKGROUND Insect metamorphosis relies on temporal and spatial cues that are precisely controlled. Previous studies in Drosophila have shown that untimely activation of genes that are essential to metamorphosis results in growth defects, developmental delay and death. Multiple factors exist that safeguard these genes against dysregulated expression. The list of identified negative regulators that play such a role in Drosophila development continues to expand. RESULTS By using RNAi transgene-induced gene silencing coupled to spatio/temporal assessment, we have unraveled an important role for the Drosophila dopamine 1-like receptor, Dop1R2, in development. We show that Dop1R2 knockdown leads to pre-adult lethality. In adults that escape death, abnormal wing expansion and/or melanization defects occur. Furthermore we show that salivary gland expression of this GPCR during the late larval/prepupal stage is essential for the flies to survive through adulthood. In addition to RNAi-induced effects, treatment of larvae with the high affinity D1-like receptor antagonist flupenthixol, also results in developmental arrest, and in morphological defects comparable to those seen in Dop1R2 RNAi flies. To examine the basis for pupal lethality in Dop1R2 RNAi flies, we carried out transcriptome analysis. These studies revealed up-regulation of genes that respond to ecdysone, regulate morphogenesis and/or modulate defense/immunity. CONCLUSION Taken together our findings suggest a role for Dop1R2 in the repression of genes that coordinate metamorphosis. Premature release of this inhibition is not tolerated by the developing fly.
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Affiliation(s)
- Kimberly Regna
- Department of Biology, Boston College, Chestnut Hill, MA, 02467, USA
| | - Peri T Kurshan
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA, 02111, USA.,Present Address: Department of Biology, Stanford University, California, 94305, USA
| | - Benjamin N Harwood
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA, 02111, USA
| | - Adam M Jenkins
- Department of Biology, Boston College, Chestnut Hill, MA, 02467, USA
| | - Chao-Qiang Lai
- Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, 02111, USA
| | - Marc A T Muskavitch
- Department of Biology, Boston College, Chestnut Hill, MA, 02467, USA.,Discovery Research, Biogen Idec, Cambridge, MA, 02142, USA
| | - Alan S Kopin
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA, 02111, USA
| | - Isabelle Draper
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA, 02111, USA.
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