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Caputo M, Ivanova D, Chasserot-Golaz S, Doussau F, Haeberlé AM, Royer C, Ozkan S, Ecard J, Vitale N, Cousin MA, Tóth P, Gasman S, Ory S. Phospholipid Scramblase 1 Controls Efficient Neurotransmission and Synaptic Vesicle Retrieval at Cerebellar Synapses. J Neurosci 2024; 44:e0042242024. [PMID: 38839301 PMCID: PMC11223464 DOI: 10.1523/jneurosci.0042-24.2024] [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: 01/08/2024] [Revised: 04/23/2024] [Accepted: 04/28/2024] [Indexed: 06/07/2024] Open
Abstract
Phospholipids (PLs) are asymmetrically distributed at the plasma membrane. This asymmetric lipid distribution is transiently altered during calcium-regulated exocytosis, but the impact of this transient remodeling on presynaptic function is currently unknown. As phospholipid scramblase 1 (PLSCR1) randomizes PL distribution between the two leaflets of the plasma membrane in response to calcium activation, we set out to determine its role in neurotransmission. We report here that PLSCR1 is expressed in cerebellar granule cells (GrCs) and that PLSCR1-dependent phosphatidylserine egress occurred at synapses in response to neuron stimulation. Synaptic transmission is impaired at GrC Plscr1 -/- synapses, and both PS egress and synaptic vesicle (SV) endocytosis are inhibited in Plscr1 -/- cultured neurons from male and female mice, demonstrating that PLSCR1 controls PL asymmetry remodeling and SV retrieval following neurotransmitter release. Altogether, our data reveal a novel key role for PLSCR1 in SV recycling and provide the first evidence that PL scrambling at the plasma membrane is a prerequisite for optimal presynaptic performance.
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Affiliation(s)
- Margherita Caputo
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg F-67000, France
| | - Daniela Ivanova
- Centre for Discovery Brain Sciences, Hugh Robson Building, George Square, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom
- Muir Maxwell Epilepsy Centre, Hugh Robson Building, George Square, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom
| | - Sylvette Chasserot-Golaz
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg F-67000, France
| | - Frédéric Doussau
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg F-67000, France
| | - Anne-Marie Haeberlé
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg F-67000, France
| | - Cathy Royer
- Plateforme Imagerie In Vitro, Centre National de la Recherche Scientifique UPS3256, Strasbourg F-67000, France
| | - Sebahat Ozkan
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg F-67000, France
| | - Jason Ecard
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg F-67000, France
| | - Nicolas Vitale
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg F-67000, France
| | - Michael A Cousin
- Centre for Discovery Brain Sciences, Hugh Robson Building, George Square, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom
- Muir Maxwell Epilepsy Centre, Hugh Robson Building, George Square, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom
- Simons Initiative for the Developing Brain, Hugh Robson Building, George Square, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom
| | - Petra Tóth
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg F-67000, France
| | - Stéphane Gasman
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg F-67000, France
| | - Stéphane Ory
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg F-67000, France
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2
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Wu T, Li Z, Wu Y, Yang X, Li L, Chen S, Qi B, Wang Y, Li C, Zhao Y. Exploring plant polyphenols as anti-allergic functional products to manage the growing incidence of food allergy. Front Nutr 2023; 10:1102225. [PMID: 37360292 PMCID: PMC10290203 DOI: 10.3389/fnut.2023.1102225] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 04/03/2023] [Indexed: 06/28/2023] Open
Abstract
The active substances derived from plants have received increasing attention owing to their wide range of pharmacological applications, including anti-tumor, anti-allergic, anti-viral, and anti-oxidative activities. The allergy epidemic is a growing global public health problem that threatens human health and safety. Polyphenols from plants have significant anti-allergic effects and are an important source of anti-allergic drug research and development. Here, we describe recent advances in the anti-allergic efficacy of plant polyphenols, including their comprehensive effects on cellular or animal models. The current issues and directions for future development in this field are discussed to provide a theoretical basis for the development and utilization of these active substances as anti-allergic products.
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Affiliation(s)
- Tianxiang Wu
- Key Laboratory of Aquatic Product Processing, Ministry of Agriculture and Rural Affairs, National R&D Center for Aquatic Product Processing, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Food Safety Laboratory, Ocean University of China, Qingdao, China
- Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, China
| | - Zhenxing Li
- Food Safety Laboratory, Ocean University of China, Qingdao, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
| | - Yanyan Wu
- Key Laboratory of Aquatic Product Processing, Ministry of Agriculture and Rural Affairs, National R&D Center for Aquatic Product Processing, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
| | - Xianqing Yang
- Key Laboratory of Aquatic Product Processing, Ministry of Agriculture and Rural Affairs, National R&D Center for Aquatic Product Processing, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
| | - Laihao Li
- Key Laboratory of Aquatic Product Processing, Ministry of Agriculture and Rural Affairs, National R&D Center for Aquatic Product Processing, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
| | - Shengjun Chen
- Key Laboratory of Aquatic Product Processing, Ministry of Agriculture and Rural Affairs, National R&D Center for Aquatic Product Processing, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, China
| | - Bo Qi
- Key Laboratory of Aquatic Product Processing, Ministry of Agriculture and Rural Affairs, National R&D Center for Aquatic Product Processing, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, China
| | - Yueqi Wang
- Key Laboratory of Aquatic Product Processing, Ministry of Agriculture and Rural Affairs, National R&D Center for Aquatic Product Processing, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, China
| | - Chunsheng Li
- Key Laboratory of Aquatic Product Processing, Ministry of Agriculture and Rural Affairs, National R&D Center for Aquatic Product Processing, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
| | - Yongqiang Zhao
- Key Laboratory of Aquatic Product Processing, Ministry of Agriculture and Rural Affairs, National R&D Center for Aquatic Product Processing, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
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3
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Dal Col J, Lamberti MJ, Nigro A, Casolaro V, Fratta E, Steffan A, Montico B. Phospholipid scramblase 1: a protein with multiple functions via multiple molecular interactors. Cell Commun Signal 2022; 20:78. [PMID: 35650588 PMCID: PMC9158361 DOI: 10.1186/s12964-022-00895-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 04/30/2022] [Indexed: 01/18/2023] Open
Abstract
Phospholipid scramblase 1 (PLSCR1) is the most studied protein of the scramblase family. Originally, it was identified as a membrane protein involved in maintaining plasma membrane asymmetry. However, studies conducted over the past few years have shown the involvement of PLSCR1 in several other cellular pathways. Indeed, PLSCR1 is not only embedded in the plasma membrane but is also expressed in several intracellular compartments where it interacts with a diverse repertoire of effectors, mediators, and regulators contributing to distinct cellular processes. Although most PLSCR1 interactors are thought to be cell-type specific, PLSCR1 often exerts its regulatory functions through shared mechanisms, including the trafficking of different molecules within intracellular vesicles such as endosomes, liposomes, and phagosomes. Intriguingly, besides endogenous proteins, PLSCR1 was also reported to interact with exogenous viral proteins, thereby regulating viral uptake and spread. This review aims to summarize the current knowledge about the multiple roles of PLSCR1 in distinct cellular pathways. Video Abstract
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Affiliation(s)
- Jessica Dal Col
- Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno, Baronissi, Italy.
| | - Marìa Julia Lamberti
- Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno, Baronissi, Italy.,INBIAS, CONICET-UNRC, Río Cuarto, Córdoba, Argentina
| | - Annunziata Nigro
- Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno, Baronissi, Italy
| | - Vincenzo Casolaro
- Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno, Baronissi, Italy
| | - Elisabetta Fratta
- Division of Immunopathology and Cancer Biomarkers, Centro Di Riferimento Oncologico di Aviano (CRO), IRCCS, Aviano, Italy
| | - Agostino Steffan
- Division of Immunopathology and Cancer Biomarkers, Centro Di Riferimento Oncologico di Aviano (CRO), IRCCS, Aviano, Italy
| | - Barbara Montico
- Division of Immunopathology and Cancer Biomarkers, Centro Di Riferimento Oncologico di Aviano (CRO), IRCCS, Aviano, Italy.
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Kakavas S, Karayiannis D, Mastora Z. The Complex Interplay between Immunonutrition, Mast Cells, and Histamine Signaling in COVID-19. Nutrients 2021; 13:nu13103458. [PMID: 34684460 PMCID: PMC8537261 DOI: 10.3390/nu13103458] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 09/17/2021] [Accepted: 09/27/2021] [Indexed: 12/23/2022] Open
Abstract
There is an ongoing need for new therapeutic modalities against SARS-CoV-2 infection. Mast cell histamine has been implicated in the pathophysiology of COVID-19 as a regulator of proinflammatory, fibrotic, and thrombogenic processes. Consequently, mast cell histamine and its receptors represent promising pharmacological targets. At the same time, nutritional modulation of immune system function has been proposed and is being investigated for the prevention of COVID-19 or as an adjunctive strategy combined with conventional therapy. Several studies indicate that several immunonutrients can regulate mast cell activity to reduce the de novo synthesis and/or release of histamine and other mediators that are considered to mediate, at least in part, the complex pathophysiology present in COVID-19. This review summarizes the effects on mast cell histamine of common immunonutrients that have been investigated for use in COVID-19.
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Affiliation(s)
- Sotirios Kakavas
- Critical Care Department, “Sotiria” General Hospital of Chest Diseases, 152 Mesogeion Avenue, 11527 Athens, Greece;
| | - Dimitrios Karayiannis
- Department of Clinical Nutrition, Evangelismos General Hospital of Athens, Ypsilantou 45-47, 10676 Athens, Greece
- Correspondence: ; Tel.: +30-213-2045035; Fax: +30-213-2041385
| | - Zafeiria Mastora
- First Department of Critical Care Medicine and Pulmonary Services, Evangelismos General Hospital, National and Kapodistrian University of Athens, 11527 Athens, Greece;
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5
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Hagemann PM, Nsiah-Dosu S, Hundt JE, Hartmann K, Orinska Z. Modulation of Mast Cell Reactivity by Lipids: The Neglected Side of Allergic Diseases. Front Immunol 2019; 10:1174. [PMID: 31191542 PMCID: PMC6549522 DOI: 10.3389/fimmu.2019.01174] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Accepted: 05/08/2019] [Indexed: 12/20/2022] Open
Abstract
Mast cells (MCs) have long been mainly regarded as effector cells in IgE-associated allergic disorders with potential immunoregulatory roles. Located close to the allergen entry sites in the skin and mucosa, MCs can capture foreign substances such as allergens, toxins, or noxious substances and are exposed to the danger signals produced by epithelial cells. MC reactivity shaped by tissue-specific factors is crucial for allergic responses ranging from local skin reactions to anaphylactic shock. Development of Th2 response leading to allergen-specific IgE production is a prerequisite for MC sensitization and induction of FcεRI-mediated MC degranulation. Up to now, IgE production has been mainly associated with proteins, whereas lipids present in plant pollen grains, mite fecal particles, insect venoms, or food have been largely overlooked regarding their immunostimulatory and immunomodulatory properties. Recent studies, however, have now demonstrated that lipids affect the sensitization process by modulating innate immune responses of epithelial cells, dendritic cells, and NK-T cells and thus crucially contribute to the outcome of sensitization. Whether and how lipids affect also MC effector functions in allergic reactions has not yet been fully clarified. Here, we discuss how lipids can affect MC responses in the context of allergic inflammation. Direct effects of immunomodulatory lipids on MC degranulation, changes in local lipid composition induced by allergens themselves and changes in lipid transport affecting MC reactivity are possible mechanisms by which the function of MC might be modulated.
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Affiliation(s)
- Philipp M Hagemann
- Division of Experimental Pneumology, Research Center Borstel, Leibniz Lungenzentrum, Airway Research Center North, German Center for Lung Research (DZL), Borstel, Germany
| | | | | | - Karin Hartmann
- Department of Dermatology, University of Luebeck, Luebeck, Germany.,Division of Allergy, Department of Dermatology, University of Basel, Basel, Switzerland
| | - Zane Orinska
- Division of Experimental Pneumology, Research Center Borstel, Leibniz Lungenzentrum, Airway Research Center North, German Center for Lung Research (DZL), Borstel, Germany
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6
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Tsai MH, Lee CK. STAT3 Cooperates With Phospholipid Scramblase 2 to Suppress Type I Interferon Response. Front Immunol 2018; 9:1886. [PMID: 30158934 PMCID: PMC6104169 DOI: 10.3389/fimmu.2018.01886] [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] [Received: 04/23/2018] [Accepted: 07/31/2018] [Indexed: 01/05/2023] Open
Abstract
Type I interferon (IFN-I) is a pluripotent cytokine that modulates innate and adaptive immunity. We have previously shown that STAT3 suppresses IFN-I response in a manner dependent on its N-terminal domain (NTD), but independent of its DNA-binding and transactivation ability. Using the yeast two-hybrid system, we have identified phospholipid scramblase 2 (PLSCR2) as a STAT3 NTD-binding partner and a suppressor of IFN-I response. Overexpression of PLSCR2 attenuates ISRE-driven reporter activity, which is further aggravated by co-expression of STAT3. Moreover, PLSCR2 deficiency enhances IFN-I-induced gene expression and antiviral activity without affecting the activation or nuclear translocation of STAT1 and STAT2 or the assembly of ISGF3 complex. Instead, PLSCR2 impedes promoter occupancy by ISGF3, an effect further intensified by the presence of STAT3. Moreover, palmitoylation of PLSCR2 is required for its binding to STAT3 and for this suppressive activity. In addition to STAT3, PLSCR2 also interacts with STAT2, which facilitates the suppressive effect on ISGF3-mediated transcriptional activity. Together, these results define the role of a novel STAT3–PLSCR2 axis in fine-tuning IFN-I response.
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Affiliation(s)
- Ming-Hsun Tsai
- Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chien-Kuo Lee
- Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, Taiwan
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7
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Liu ZQ, Li XX, Qiu SQ, Yu Y, Li MG, Yang LT, Li LJ, Wang S, Zheng PY, Liu ZG, Yang PC. Vitamin D contributes to mast cell stabilization. Allergy 2017; 72:1184-1192. [PMID: 27998003 DOI: 10.1111/all.13110] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/15/2016] [Indexed: 12/15/2022]
Abstract
BACKGROUND AND AIMS Mast cells are the major effector cells in allergic disorders and many other informatory disorders. The mechanism of mast cell stabilization is not fully understood. Cumulative reports indicate that vitamin D (VitD) contributes to the homeostasis in the body. This study tests a hypothesis that VitD is required in the maintenance of the stability of mast cells. METHODS The stability of mast cell lines, HMC1 cells, RBL-2H3 cells, p815 cells, and mouse bone marrow-derived mast cells (BMMC) was tested in the presence or absence of VitD3. RESULTS Mast cells activated automatically in a VitD-deficient environment. Exposure to calcitriol in the culture increased the expression of VitD receptor (VDR) in mast cells. VDR formed complexes with Lyn in mast cells to inhibit the binding of Lyn to the β chain of FcεRI and MyD88, which decreased the phosphorylation of Syk, decreased the levels of MAPK and NF-κB. VDR bound to the promoter of TNF-α to decrease the acetylation of histone H3/H4, RNA polymerase II and OCT1 (a transcription factor of TNF-α) at the promoter locus and repressed the expression of TNF-α in mast cells. CONCLUSIONS The data demonstrate that VitD is required to maintain the stability of mast cells. The deficiency of VitD results in mast cell activation.
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Affiliation(s)
- Z.-Q. Liu
- The Research Center of Allergy & Immunology; Shenzhen University School of Medicine; Shenzhen China
- Longgang ENT Hospital; Shenzhen China
| | - X.-X. Li
- The Research Center of Allergy & Immunology; Shenzhen University School of Medicine; Shenzhen China
| | - S.-Q. Qiu
- The Research Center of Allergy & Immunology; Shenzhen University School of Medicine; Shenzhen China
- Longgang ENT Hospital; Shenzhen China
| | - Y. Yu
- The Fifth Hospital; Zhengzhou University; Zhengzhou China
| | - M.-G. Li
- The Research Center of Allergy & Immunology; Shenzhen University School of Medicine; Shenzhen China
| | - L.-T. Yang
- The Research Center of Allergy & Immunology; Shenzhen University School of Medicine; Shenzhen China
- Longgang ENT Hospital; Shenzhen China
- Brain Body Institute; McMaster University; Hamilton ON Canada
| | - L.-J. Li
- Brain Body Institute; McMaster University; Hamilton ON Canada
| | - S. Wang
- The Research Center of Allergy & Immunology; Shenzhen University School of Medicine; Shenzhen China
- Longgang ENT Hospital; Shenzhen China
| | - P.-Y. Zheng
- The Fifth Hospital; Zhengzhou University; Zhengzhou China
| | - Z.-G. Liu
- The Research Center of Allergy & Immunology; Shenzhen University School of Medicine; Shenzhen China
| | - P.-C. Yang
- The Research Center of Allergy & Immunology; Shenzhen University School of Medicine; Shenzhen China
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Kassas-Guediri A, Coudrat J, Pacreau E, Launay P, Monteiro RC, Blank U, Charles N, Benhamou M. Phospholipid scramblase 1 amplifies anaphylactic reactions in vivo. PLoS One 2017; 12:e0173815. [PMID: 28282470 PMCID: PMC5345872 DOI: 10.1371/journal.pone.0173815] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 02/27/2017] [Indexed: 02/07/2023] Open
Abstract
Mast cells are critical actors of hypersensitivity type I (allergic) reactions by the release of vasoactive and proinflammatory mediators following their activation by aggregation of the high-affinity receptor for immunoglobulin E (FcεRI). We have previously identified Phospholipid Scramblase 1 (PLSCR1) as a new molecular intermediate of FcεRI signaling that amplifies degranulation of the rat mast cell line RBL-2H3. Here we characterized primary mast cells from Plscr1-/- mice. The absence of PLSCR1 expression did not impact mast cell differentiation as evidenced by unaltered FcεRI expression, general morphology, amount of histamine stored and expression of FcεRI signal effector molecules. No detectable mast cell deficiency was observed in Plscr1-/- adult mice. In dose-response and time-course experiments, primary cultures of mast cells (bone marrow-derived mast cells and peritoneal cell-derived mast cells) generated from Plscr1-/- mice exhibited a reduced release of β-hexosaminidase upon FcεRI engagement as compared to their wild-type counterparts. In vivo, Plscr1-/- mice were protected in a model of passive systemic anaphylaxis when compared to wild-type mice, which was consistent with an observed decrease in the amounts of histamine released in the serum of Plscr1-/- mice during the reaction. Therefore, PLSCR1 aggravates anaphylactic reactions by increasing FcεRI-dependent mast cell degranulation. PLSCR1 could be a new therapeutic target in allergy.
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Affiliation(s)
- Asma Kassas-Guediri
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
| | - Julie Coudrat
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
| | - Emeline Pacreau
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
| | - Pierre Launay
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
| | - Renato C. Monteiro
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
| | - Ulrich Blank
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
| | - Nicolas Charles
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
| | - Marc Benhamou
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
- * E-mail:
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9
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Lee AJ, Ro M, Kim JH. Leukotriene B4 Receptor 2 Is Critical for the Synthesis of Vascular Endothelial Growth Factor in Allergen-Stimulated Mast Cells. THE JOURNAL OF IMMUNOLOGY 2016; 197:2069-78. [PMID: 27489284 DOI: 10.4049/jimmunol.1502565] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 07/05/2016] [Indexed: 01/31/2023]
Abstract
Mast cells are among the principal effector cells in the pathogenesis of allergic asthma. In allergic reactions, allergen (Ag)-induced cross-linking of IgE bound to FcεRI on mast cells results in the production of vascular endothelial growth factor (VEGF), which is essential for the initiation and development of the allergic response. Despite the central role of VEGF in allergic asthma, the signaling events responsible for the production of VEGF remain unclear, particularly in Ag-stimulated mast cells. In the present study, we observed that blocking leukotriene B4 receptor 2 (BLT2) completely abrogated the production of VEGF in Ag-stimulated bone marrow-derived mast cells (BMMCs). The synthesis of BLT2 ligands (leukotriene B4 and 12(S)-hydroxyeicosatetraenoic acid) was also required for VEGF production, suggesting a mediating role of an autocrine BLT2 ligands-BLT2 axis in the production of VEGF in mast cells. The NADPH oxidase 1-reactive oxygen species-NF-κB cascade is downstream of BLT2 during Ag signaling to VEGF synthesis in mast cells. Furthermore, the level of VEGF synthesis in genetically mast cell-deficient Kit(W/Wv) mice was significantly lower than that in wild-type mice in the OVA-induced asthma model, suggesting that mast cells play a critical role in the synthesis of VEGF in OVA-induced allergic asthma. Importantly, VEGF production was restored to the levels observed in wild-type mice after adoptive transfer of normal BMMCs into Kit(W/Wv) mice but was not restored in BLT2(-/-) BMMC-reconstituted Kit(W/Wv) mice in the OVA-induced asthma model. Taken together, our results suggest that BLT2 expression in mast cells is essential for the production of VEGF in OVA-induced allergic asthma.
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Affiliation(s)
- A-Jin Lee
- School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea
| | - MyungJa Ro
- School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea
| | - Jae-Hong Kim
- School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea
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10
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New Regulatory Roles of Galectin-3 in High-Affinity IgE Receptor Signaling. Mol Cell Biol 2016; 36:1366-82. [PMID: 26929198 DOI: 10.1128/mcb.00064-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 02/16/2016] [Indexed: 01/18/2023] Open
Abstract
Aggregation of the high-affinity receptor for IgE (FcεRI) in mast cells initiates activation events that lead to degranulation and release of inflammatory mediators. To better understand the signaling pathways and genes involved in mast cell activation, we developed a high-throughput mast cell degranulation assay suitable for RNA interference experiments using lentivirus-based short hairpin RNA (shRNA) delivery. We tested 432 shRNAs specific for 144 selected genes for effects on FcεRI-mediated mast cell degranulation and identified 15 potential regulators. In further studies, we focused on galectin-3 (Gal3), identified in this study as a negative regulator of mast cell degranulation. FcεRI-activated cells with Gal3 knockdown exhibited upregulated tyrosine phosphorylation of spleen tyrosine kinase and several other signal transduction molecules and enhanced calcium response. We show that Gal3 promotes internalization of IgE-FcεRI complexes; this may be related to our finding that Gal3 is a positive regulator of FcεRI ubiquitination. Furthermore, we found that Gal3 facilitates mast cell adhesion and motility on fibronectin but negatively regulates antigen-induced chemotaxis. The combined data indicate that Gal3 is involved in both positive and negative regulation of FcεRI-mediated signaling events in mast cells.
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Martin KR, Kantari-Mimoun C, Yin M, Pederzoli-Ribeil M, Angelot-Delettre F, Ceroi A, Grauffel C, Benhamou M, Reuter N, Saas P, Frachet P, Boulanger CM, Witko-Sarsat V. Proteinase 3 Is a Phosphatidylserine-binding Protein That Affects the Production and Function of Microvesicles. J Biol Chem 2016; 291:10476-89. [PMID: 26961880 DOI: 10.1074/jbc.m115.698639] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Indexed: 01/05/2023] Open
Abstract
Proteinase 3 (PR3), the autoantigen in granulomatosis with polyangiitis, is expressed at the plasma membrane of resting neutrophils, and this membrane expression increases during both activation and apoptosis. Using surface plasmon resonance and protein-lipid overlay assays, this study demonstrates that PR3 is a phosphatidylserine-binding protein and this interaction is dependent on the hydrophobic patch responsible for membrane anchorage. Molecular simulations suggest that PR3 interacts with phosphatidylserine via a small number of amino acids, which engage in long lasting interactions with the lipid heads. As phosphatidylserine is a major component of microvesicles (MVs), this study also examined the consequences of this interaction on MV production and function. PR3-expressing cells produced significantly fewer MVs during both activation and apoptosis, and this reduction was dependent on the ability of PR3 to associate with the membrane as mutating the hydrophobic patch restored MV production. Functionally, activation-evoked MVs from PR3-expressing cells induced a significantly larger respiratory burst in human neutrophils compared with control MVs. Conversely, MVs generated during apoptosis inhibited the basal respiratory burst in human neutrophils, and those generated from PR3-expressing cells hampered this inhibition. Given that membrane expression of PR3 is increased in patients with granulomatosis with polyangiitis, MVs generated from neutrophils expressing membrane PR3 may potentiate oxidative damage of endothelial cells and promote the systemic inflammation observed in this disease.
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Affiliation(s)
- Katherine R Martin
- From the INSERM, U1016, Institut Cochin, 75014 Paris, France, CNRS-UMR8104, 75014 Paris, France, Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France, Center of Excellence, Labex Inflamex, 75013 Paris, France
| | - Chahrazade Kantari-Mimoun
- From the INSERM, U1016, Institut Cochin, 75014 Paris, France, CNRS-UMR8104, 75014 Paris, France, Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France, Center of Excellence, Labex Inflamex, 75013 Paris, France
| | - Min Yin
- Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France, INSERM, U970, Paris Cardiovascular Research Center PARCC, 75015 Paris, France
| | - Magali Pederzoli-Ribeil
- From the INSERM, U1016, Institut Cochin, 75014 Paris, France, CNRS-UMR8104, 75014 Paris, France, Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France, Center of Excellence, Labex Inflamex, 75013 Paris, France
| | - Fanny Angelot-Delettre
- INSERM, UMR1098, Université Bourgogne Franche-Comté, Etablissement Français du Sang Bourgogne Franche-Comté, 25000 Besançon, France, Center of Excellence, Labex LipSTIC, 25000 Besançon, France
| | - Adam Ceroi
- INSERM, UMR1098, Université Bourgogne Franche-Comté, Etablissement Français du Sang Bourgogne Franche-Comté, 25000 Besançon, France, Center of Excellence, Labex LipSTIC, 25000 Besançon, France
| | - Cédric Grauffel
- Departments of Informatics and Molecular Biology, University of Bergen, 5008 Bergen, Norway
| | - Marc Benhamou
- Center of Excellence, Labex Inflamex, 75013 Paris, France, INSERM U1149/CNRS ERL8252, Université Paris-Diderot, 75018 Paris, France
| | - Nathalie Reuter
- Departments of Informatics and Molecular Biology, University of Bergen, 5008 Bergen, Norway
| | - Philippe Saas
- INSERM, UMR1098, Université Bourgogne Franche-Comté, Etablissement Français du Sang Bourgogne Franche-Comté, 25000 Besançon, France, Center of Excellence, Labex LipSTIC, 25000 Besançon, France
| | - Philippe Frachet
- Université Grenoble Alpes, Institut de Biologie Structurale (IBS), 38044 Grenoble, France, CNRS, IBS, 38044 Grenoble, France, and Commissariat à l'Energie Atomique, IBS, 38000 Grenoble, France
| | - Chantal M Boulanger
- Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France, INSERM, U970, Paris Cardiovascular Research Center PARCC, 75015 Paris, France
| | - Véronique Witko-Sarsat
- From the INSERM, U1016, Institut Cochin, 75014 Paris, France, CNRS-UMR8104, 75014 Paris, France, Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France, Center of Excellence, Labex Inflamex, 75013 Paris, France,
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Herate C, Ramdani G, Grant NJ, Marion S, Gasman S, Niedergang F, Benichou S, Bouchet J. Phospholipid Scramblase 1 Modulates FcR-Mediated Phagocytosis in Differentiated Macrophages. PLoS One 2016; 11:e0145617. [PMID: 26745724 PMCID: PMC4712888 DOI: 10.1371/journal.pone.0145617] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 11/04/2015] [Indexed: 12/24/2022] Open
Abstract
Phospholipid Scramblase 1 (PLSCR1) was initially characterized as a type II transmembrane protein involved in bilayer movements of phospholipids across the plasma membrane leading to the cell surface exposure of phosphatidylserine, but other cellular functions have been ascribed to this protein in signaling processes and in the nucleus. In the present study, expression and functions of PLSCR1 were explored in specialized phagocytic cells of the monocyte/macrophage lineage. The expression of PLSCR1 was found to be markedly increased in monocyte-derived macrophages compared to undifferentiated primary monocytes. Surprisingly, this 3-fold increase in PLSCR1 expression correlated with an apparent modification in the membrane topology of the protein at the cell surface of differentiated macrophages. While depletion of PLSCR1 in the monocytic THP-1 cell-line with specific shRNA did not inhibit the constitutive cell surface exposure of phosphatidylserine observed in differentiated macrophages, a net increase in the FcR-mediated phagocytic activity was measured in PLSCR1-depleted THP-1 cells and in bone marrow-derived macrophages from PLSCR1 knock-out mice. Reciprocally, phagocytosis was down-regulated in cells overexpressing PLSCR1. Since endogenous PLSCR1 was recruited both in phagocytic cups and in phagosomes, our results reveal a specific role for induced PLSCR1 expression in the modulation of the phagocytic process in differentiated macrophages.
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Affiliation(s)
- Cecile Herate
- Inserm U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
| | - Ghania Ramdani
- Inserm U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
| | - Nancy J. Grant
- Institut des Neurosciences Cellulaires et Intégratives, CNRS UPR3212, and Université de Strasbourg, Strasbourg, France
| | - Sabrina Marion
- Inserm U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
| | - Stephane Gasman
- Institut des Neurosciences Cellulaires et Intégratives, CNRS UPR3212, and Université de Strasbourg, Strasbourg, France
| | - Florence Niedergang
- Inserm U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
| | - Serge Benichou
- Inserm U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
- * E-mail:
| | - Jerome Bouchet
- Inserm U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
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Tubby-like protein superfamily member PLSCR3 functions as a negative regulator of adipogenesis in mouse 3T3-L1 preadipocytes by suppressing induction of late differentiation stage transcription factors. Biosci Rep 2015; 36:e00287. [PMID: 26677203 PMCID: PMC4725246 DOI: 10.1042/bsr20150215] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 12/15/2015] [Indexed: 02/08/2023] Open
Abstract
Decrease in intracellular amount of phospholipid scramblase 3 (PLSCR3) is accompanied by enhanced unconventional secretion during differentiation of mouse preadipocytic 3T3-L1 cells. Forced overexpression of PLSCR3 in 3T3-L1 cells inhibited adipogenesis by suppressing induction of late stage pro-adipogenic transcription factors. PLSCR3 (phospholipid scramblase 3, Scr3) belongs to the superfamily of membrane-associated transcription regulators named Tubby-like proteins (TULPs). Physiological phospholipid scrambling activities of PLSCRs in vivo have been skeptically argued, and knowledge of the biological functions of Scr3 is limited. We investigated the expression of Scr3 during differentiation of mouse 3T3-L1 preadipocytes by Western blotting (WB) and by reverse-transcription and real-time quantitative PCR (RT-qPCR). The Scr3 protein decreased during 3T3-L1 differentiation accompanied by a reduction in the mRNA level, and there was a significant increase in the amount of Scr3 protein secreted into the culture medium in the form of extracellular microvesicles (exosomes). On the other hand, Scr3 expression did not significantly decrease, and the secretion of Scr3 in 3T3 Swiss-albino fibroblasts (a parental cell-line of 3T3-L1) was not increased by differentiation treatment. Overexpression of human Scr3 during 3T3-L1 differentiation suppressed triacylglycerol accumulation and inhibited induction of the mRNAs of late stage pro-adipogenic transcription factors [CCAAT/enhancer-binding protein α (C/EBPα) and peroxisome proliferator-activated receptor γ (PPARγ)] and X-box-binding protein 1 (XBP1). Expression of early stage pro-adipogenic transcription factors (C/EBPβ and C/EBPδ) was not significantly affected. These results suggest that Scr3 functions as a negative regulator of adipogenesis in 3T3-L1 cells at a specific differentiation stage and that decrease in the intracellular amount of Scr3 protein caused by reduction in Scr3 mRNA expression and enhanced secretion of Scr3 protein appears to be important for appropriate adipocyte differentiation.
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14
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Two c-Myc binding sites are crucial in upregulating the expression of human phospholipid scramblase 1 gene. Biochem Biophys Res Commun 2015; 469:412-7. [PMID: 26679604 DOI: 10.1016/j.bbrc.2015.11.131] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 11/29/2015] [Indexed: 11/21/2022]
Abstract
Human phospholipid scramblase 1 (hPLSCR1) is a type II endofacial membrane protein which mediates bi-directional transport of phospholipids across the plasma membrane. hPLSCR1, a multifunctional protein with variety of roles in apoptosis, tumor progression, cell signaling and anti-viral defense. The expression of such a multifunctional protein should be under tight regulation. Apart from a single report showing snail mediated down regulation of hPLSCR1, the molecular mechanisms regulating the expression of scramblases are not well elucidated. In this study we identified c-Myc as a transcriptional regulator of hPLSCR1. Transcription factor prediction tool ConSite predicted three binding sites for c-Myc. Reporter gene assays and western blot analysis revealed c-Myc mediated up regulation of hPLSCR1 expression. Deletion construct -790 lacking one c-Myc binding site showed a 27% decrease in promoter activity while deletion construct -469 lacking two c-Myc binding sites showed a 62% decrease in promoter activity. Site directed mutagenesis revealed the importance of c-Myc binding sites from -751 to -756 and -548 to -553 on the promoter of hPLSCR1in transcriptionally regulating the expression of hPLSCR1. The results were further confirmed by shRNA mediated knock down of endogenous c-Myc and in vivo interactions by ChIP assay.
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15
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Rysavy NM, Shimoda LMN, Dixon AM, Speck M, Stokes AJ, Turner H, Umemoto EY. Beyond apoptosis: the mechanism and function of phosphatidylserine asymmetry in the membrane of activating mast cells. BIOARCHITECTURE 2015; 4:127-37. [PMID: 25759911 DOI: 10.1080/19490992.2014.995516] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Loss of plasma membrane asymmetry is a hallmark of apoptosis, but lipid bilayer asymmetry and loss of asymmetry can contribute to numerous cellular functions and responses that are independent of programmed cell death. Exofacial exposure of phosphatidylserine occurs in lymphocytes and mast cells after antigenic stimulation and in the absence of apoptosis, suggesting that there is a functional requirement for phosphatidylserine exposure in immunocytes. In this review we examine current ideas as to the nature of this functional role in mast cell activation. Mechanistically, there is controversy as to the candidate proteins responsible for phosphatidylserine translocation from the internal to external leaflet, and here we review the candidacies of mast cell PLSCR1 and TMEM16F. Finally we examine the potential relationship between functionally important mast cell membrane perturbations and phosphatidylserine exposure during activation.
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Key Words
- ABCA, ABC binding cassette family A
- CRAC, calcium release activated channel
- GPMV, giant plasma membrane vesicle
- ITIM, immunoreceptor tyrosine based inhibitory motif
- PLA2, phospholipase A2
- PLSCR, phospholipid scramblase
- PMA, phorbol 12,13-myristate acetate
- RBL, rat basophilic leukemia
- RFU, relative fluorescence units
- ROI, region of interest
- TMEM, transmembrane protein
- TMEM16F
- WGA, wheat germ agglutinin
- mast cells
- membrane lipids
- phosphatidylserine
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Affiliation(s)
- Noel M Rysavy
- a Laboratory of Immunology and Signal Transduction ; Department of Biology; Chaminade University ; Honolulu , Hawai'i USA
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16
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Kodigepalli KM, Nanjundan M. Induction of PLSCR1 in a STING/IRF3-dependent manner upon vector transfection in ovarian epithelial cells. PLoS One 2015; 10:e0117464. [PMID: 25658875 PMCID: PMC4320088 DOI: 10.1371/journal.pone.0117464] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 12/23/2014] [Indexed: 12/14/2022] Open
Abstract
Toll-like receptors (TLRs) are the primary sensors of the innate immune system that recognize pathogenic nucleic acids including double-stranded plasmid DNA (dsDNA). TLR signaling activates multiple pathways including IRF3 which is involved in transcriptional induction of inflammatory cytokines (i.e. interferons (IFNs)). Phospholipid scramblase 1, PLSCR1, is a highly inducible IFN-regulated gene mediating anti-viral properties of IFNs. Herein, we report a novel finding that dsDNA transfection in T80 immortalized normal ovarian surface epithelial cell line leads to a marked increase in PLSCR1 mRNA and protein. We also noted a comparable response in primary mammary epithelial cells (HMECs). Similar to IFN-2α treated cells, de novo synthesized PLSCR1 was localized predominantly to the plasma membrane. dsDNA transfection, in T80 and HMEC cells, led to activation of MAPK and IRF3. Although inhibition of MAPK (using U0126) did not modulate PLSCR1 mRNA and protein, IRF3 knockdown (using siRNA) significantly ablated the PLSCR1 induction. In prior studies, the activation of IRF3 was shown to be mediated by cGAS-STING pathway. To investigate the contribution of STING to PLSCR1 induction, we utilized siRNA to reduce STING expression and observed that PLSCR1 protein was markedly reduced. In contrast to normal T80/HMECs, the phosphorylation of IRF3 as well as induction of STING and PLSCR1 were absent in ovarian cancer cells (serous, clear cell, and endometrioid) suggesting that the STING/IRF3 pathway may be dysregulated in these cancer cells. However, we also noted induction of different TLR and IFN mRNAs between the T80 and HEY (serous epithelial ovarian carcinoma) cell lines upon dsDNA transfection. Collectively, these results indicate that the STING/IRF3 pathway, activated following dsDNA transfection, contributes to upregulation of PLSCR1 in ovarian epithelial cells.
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Affiliation(s)
- Karthik M. Kodigepalli
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, Florida, 33620, United States of America
| | - Meera Nanjundan
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, Florida, 33620, United States of America
- * E-mail:
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17
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Kodigepalli KM, Bowers K, Sharp A, Nanjundan M. Roles and regulation of phospholipid scramblases. FEBS Lett 2014; 589:3-14. [PMID: 25479087 DOI: 10.1016/j.febslet.2014.11.036] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 11/22/2014] [Accepted: 11/24/2014] [Indexed: 02/06/2023]
Abstract
Phospholipid scramblase activity is involved in the collapse of phospholipid (PL) asymmetry at the plasma membrane leading to externalization of phosphatidylserine. This activity is crucial for initiation of the blood coagulation cascade and for recognition/elimination of apoptotic cells by macrophages. Efforts to identify gene products associated with this activity led to the characterization of PL scramblase (PLSCR) and XKR family members which contribute to phosphatidylserine exposure in response to apoptotic stimuli. Meanwhile, TMEM16 family members were identified to externalize phosphatidylserine in response to elevated calcium in Scott syndrome platelets, which is critical for activation of the coagulation cascade. Herein, we report their mechanisms of gene regulation, molecular functions independent of their scrambling activity, and their potential roles in pathogenic conditions.
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Affiliation(s)
- Karthik M Kodigepalli
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, FL 33620, United States
| | - Kiah Bowers
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, FL 33620, United States
| | - Arielle Sharp
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, FL 33620, United States
| | - Meera Nanjundan
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, FL 33620, United States.
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18
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Kassas A, Moura IC, Yamashita Y, Scheffel J, Guérin-Marchand C, Blank U, Sims PJ, Wiedmer T, Monteiro RC, Rivera J, Charles N, Benhamou M. Regulation of the tyrosine phosphorylation of Phospholipid Scramblase 1 in mast cells that are stimulated through the high-affinity IgE receptor. PLoS One 2014; 9:e109800. [PMID: 25289695 PMCID: PMC4188579 DOI: 10.1371/journal.pone.0109800] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Accepted: 09/14/2014] [Indexed: 01/05/2023] Open
Abstract
Engagement of high-affinity immunoglobulin E receptors (FcεRI) activates two signaling pathways in mast cells. The Lyn pathway leads to recruitment of Syk and to calcium mobilization whereas the Fyn pathway leads to phosphatidylinositol 3-kinase recruitment. Mapping the connections between both pathways remains an important task to be completed. We previously reported that Phospholipid Scramblase 1 (PLSCR1) is phosphorylated on tyrosine after cross-linking FcεRI on RBL-2H3 rat mast cells, amplifies mast cell degranulation, and is associated with both Lyn and Syk tyrosine kinases. Here, analysis of the pathway leading to PLSCR1 tyrosine phosphorylation reveals that it depends on the FcRγ chain. FcεRI aggregation in Fyn-deficient mouse bone marrow-derived mast cells (BMMC) induced a more robust increase in FcεRI-dependent tyrosine phosphorylation of PLSCR1 compared to wild-type cells, whereas PLSCR1 phosphorylation was abolished in Lyn-deficient BMMC. Lyn association with PLSCR1 was not altered in Fyn-deficient BMMC. PLSCR1 phosphorylation was also dependent on the kinase Syk and significantly, but partially, dependent on detectable calcium mobilization. Thus, the Lyn/Syk/calcium axis promotes PLSCR1 phosphorylation in multiple ways. Conversely, the Fyn-dependent pathway negatively regulates it. This study reveals a complex regulation for PLSCR1 tyrosine phosphorylation in FcεRI-activated mast cells and that PLSCR1 sits at a crossroads between Lyn and Fyn pathways.
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Affiliation(s)
- Asma Kassas
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
| | - Ivan C. Moura
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
| | - Yumi Yamashita
- Laboratory of Molecular Immunogenetics, Molecular Immunology and Inflammation Branch, NIAMSD, NIH, Bethesda, Maryland, United States of America
| | - Jorg Scheffel
- Laboratory of Molecular Immunogenetics, Molecular Immunology and Inflammation Branch, NIAMSD, NIH, Bethesda, Maryland, United States of America
| | - Claudine Guérin-Marchand
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
| | - Ulrich Blank
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
| | - Peter J. Sims
- Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Therese Wiedmer
- Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Renato C. Monteiro
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
| | - Juan Rivera
- Laboratory of Molecular Immunogenetics, Molecular Immunology and Inflammation Branch, NIAMSD, NIH, Bethesda, Maryland, United States of America
| | - Nicolas Charles
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
- * E-mail: (NC); (MB)
| | - Marc Benhamou
- INSERM U1149, Faculté de Médecine Xavier Bichat, Paris, France
- University Paris-Diderot, Sorbonne Paris Cité, Laboratoire d’excellence INFLAMEX, DHU FIRE, Paris, France
- * E-mail: (NC); (MB)
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The C-terminal transmembrane domain of human phospholipid scramblase 1 is essential for the protein flip-flop activity and Ca²⁺-binding. J Membr Biol 2013; 247:155-65. [PMID: 24343571 DOI: 10.1007/s00232-013-9619-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 11/26/2013] [Indexed: 10/25/2022]
Abstract
Human phospholipid scramblase 1 (SCR) is a 318 amino acid protein that was originally described as catalyzing phospholipid transbilayer (flip-flop) motion in plasma membranes in a Ca²⁺-dependent, ATP-independent way. Further studies have suggested an intranuclear role for this protein in addition. A putative transmembrane domain located at the C terminus (aa 291-309) has been related to the flip-flop catalysis. In order to clarify the role of the C-terminal region of SCR, a mutant was produced (SCRΔ) in which the last 28 amino acid residues were lacking, including the α-helix. SCRΔ had lost the scramblase activity and its affinity for Ca²⁺ was decreased by one order of magnitude. Fluorescence and IR spectroscopic studies revealed that the C-terminal region of SCR was essential for the proper folding of the protein. Moreover, it was found that Ca²⁺ exerted an overall destabilizing effect on SCR, which might facilitate its binding to membranes.
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ALG-2-interacting Tubby-like protein superfamily member PLSCR3 is secreted by an exosomal pathway and taken up by recipient cultured cells. Biosci Rep 2013; 33:e00026. [PMID: 23350699 PMCID: PMC3590573 DOI: 10.1042/bsr20120123] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
PLSCRs (phospholipid scramblases) are palmitoylated membrane-associating proteins. Regardless of the given names, their physiological functions are not clear and thought to be unrelated to phospholipid scrambling activities observed in vitro. Using a previously established cell line of HEK-293 (human embryonic kidney-293) cells constitutively expressing human Scr3 (PLSCR3) that interacts with ALG-2 (apoptosis-linked gene 2) Ca2+-dependently, we found that Scr3 was secreted into the culture medium. Secretion of Scr3 was suppressed by 2-BP (2-bromopalmitate, a palmitoylation inhibitor) and by GW4869 (an inhibitor of ceramide synthesis). Secreted Scr3 was recovered in exosomal fractions by sucrose density gradient centrifugation. Palmitoylation sites and the N-terminal Pro-rich region were necessary for efficient secretion, but ABSs (ALG-2-binding sites) were dispensable. Overexpression of GFP (green fluorescent protein)-fused VPS4BE235Q, a dominant negative mutant of an AAA (ATPase associated with various cellular activities) ATPase with a defect in disassembling ESCRT (endosomal sorting complex required for transport)-III subunits, significantly reduced secretion of Scr3. Immunofluorescence microscopic analyses showed that Scr3 was largely localized to enlarged endosomes induced by overexpression of a GFP-fused constitutive active mutant of Rab5A (GFP–Rab5AQ79L). Secreted Scr3 was taken up by HeLa cells, suggesting that Scr3 functions as a cell-to-cell transferable modulator carried by exosomes in a paracrine manner.
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21
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Inhibitory effect of eriodictyol on IgE/Ag-induced type I hypersensitivity. Biosci Biotechnol Biochem 2012; 76:1285-90. [PMID: 22785465 DOI: 10.1271/bbb.110952] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Mast cells are the principal effector cells involved in the allergic response, through the release of histamine. We investigated the effect of eriodictyol, derived from the painted maple and yerba santa, on mast cell degranulation and on an allergic response in an animal model. We also investigated its effect on the expression of the ceramide kinase (CERK) involved in calcium-dependent degranulation, and on ceramide activation by multiple cytokines. Eriodictyol suppressed the release of beta-hexosaminidase, a marker of degranulation, and the expression of interleukin (IL)-4 mRNA. It inhibited the expression of CERK mRNA, reduced the ceramide concentration in antigen-stimulated mast cells, and suppressed the passive cutaneous anaphylaxis (PCA) reaction in mice in a dose-dependent manner. These results suggest that eriodictyol can inhibit mast cell degranulation through inhibition of ceramide kinase, and that it might potentially serve as an anti-allergic agent.
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Gong Q, Cheng M, Chen H, Liu X, Si Y, Yang Y, Yuan Y, Jin C, Yang W, He F, Wang J. Phospholipid scramblase 1 mediates hepatitis C virus entry into host cells. FEBS Lett 2011; 585:2647-52. [PMID: 21806988 DOI: 10.1016/j.febslet.2011.07.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Revised: 07/06/2011] [Accepted: 07/13/2011] [Indexed: 01/23/2023]
Abstract
Hepatitis C virus (HCV) infects human hepatocytes through several host factors. However, other prerequisite factors for viral entry remain to be identified. Using a yeast two-hybrid screen, we found that human phospholipid scramblase 1 interacts with HCV envelope proteins E1 and E2. These physical interactions were confirmed by co-immunoprecipitation and GST pull-down assays. Knocking down the expression of PLSCR1 inhibited the entry of HCV pseudoparticles. Moreover, PLSCR1 was required for the initial attachment of HCV onto hepatoma cells, where it specifically interacted with entry factor OCLN. We show that PLSCR1 is a novel attachment factor for HCV entry.
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Affiliation(s)
- Qiaoling Gong
- Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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Chen CW, Sowden M, Zhao Q, Wiedmer T, Sims PJ. Nuclear phospholipid scramblase 1 prolongs the mitotic expansion of granulocyte precursors during G-CSF-induced granulopoiesis. J Leukoc Biol 2011; 90:221-33. [PMID: 21447647 DOI: 10.1189/jlb.0111006] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
PLSCR1-/- mice exhibit normal, steady-state hematologic parameters but impaired emergency granulopoiesis upon in vivo administration of G-CSF. The mechanism by which PLSCR1 contributes to G-CSF-induced neutrophil production is largely unknown. We now report that the expansion of bone marrow myelocytes upon in vivo G-CSF treatment is reduced in PLSCR1-/- mice relative to WT. Using SCF-ER-Hoxb8-immortalized myeloid progenitors to examine the progression of G-CSF-driven granulocytic differentiation in vitro, we found that PLSCR1 prolongs the period of mitotic expansion of proliferative granulocyte precursors, thereby giving rise to increased neutrophil production from their progenitors. This effect of PLSCR1 is blocked by a ΔNLS-PLSCR1, which prevents its nuclear import. By contrast, mutation that prevents the membrane association of PLSCR1 has minimal impact on the role of PLSCR1 in G-CSF-induced granulopoiesis. These data imply that the capacity of PLSCR1 to augment G-CSF-dependent production of mature neutrophils from myeloid progenitors is unrelated to its reported activities at the endofacial surface of the plasma membrane but does require entry of the protein into the nucleus, suggesting that this response is mediated through the observed effects of PLSCR1 on gene transcription.
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Affiliation(s)
- Chun-Wei Chen
- Department of Pathology and Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
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Benhamou M, Blank U. Stimulus-secretion coupling by high-affinity IgE receptor: new developments. FEBS Lett 2010; 584:4941-8. [PMID: 20851120 DOI: 10.1016/j.febslet.2010.09.023] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2010] [Revised: 08/20/2010] [Accepted: 09/13/2010] [Indexed: 12/20/2022]
Abstract
Stimulation of mast cells through their high affinity IgE receptor (FcεRI) leads to the secretion of pre- and neoformed soluble mediators through vesicular carriers. This process is highly regulated in order to adapt the secretion of these potentially dangerous factors to the physiological needs. This regulation requires numerous essential effectors that are necessary to transmit the initial signal of FcεRI aggregation and couple it to the sophisticated secretory machinery of membrane fusion. Studies in recent years have led to the discovery of a series of new effector molecules that link FcεRI to secretion. We describe here some of the new developments that have allowed to obtain a clearer picture of stimulus/secretion coupling in mast cells.
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Callens C, Coulon S, Naudin J, Radford-Weiss I, Boissel N, Raffoux E, Wang PHM, Agarwal S, Tamouza H, Paubelle E, Asnafi V, Ribeil JA, Dessen P, Canioni D, Chandesris O, Rubio MT, Beaumont C, Benhamou M, Dombret H, Macintyre E, Monteiro RC, Moura IC, Hermine O. Targeting iron homeostasis induces cellular differentiation and synergizes with differentiating agents in acute myeloid leukemia. ACTA ACUST UNITED AC 2010; 207:731-50. [PMID: 20368581 PMCID: PMC2856037 DOI: 10.1084/jem.20091488] [Citation(s) in RCA: 146] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Differentiating agents have been proposed to overcome the impaired cellular differentiation in acute myeloid leukemia (AML). However, only the combinations of all-trans retinoic acid or arsenic trioxide with chemotherapy have been successful, and only in treating acute promyelocytic leukemia (also called AML3). We show that iron homeostasis is an effective target in the treatment of AML. Iron chelating therapy induces the differentiation of leukemia blasts and normal bone marrow precursors into monocytes/macrophages in a manner involving modulation of reactive oxygen species expression and the activation of mitogen-activated protein kinases (MAPKs). 30% of the genes most strongly induced by iron deprivation are also targeted by vitamin D3 (VD), a well known differentiating agent. Iron chelating agents induce expression and phosphorylation of the VD receptor (VDR), and iron deprivation and VD act synergistically. VD magnifies activation of MAPK JNK and the induction of VDR target genes. When used to treat one AML patient refractory to chemotherapy, the combination of iron-chelating agents and VD resulted in reversal of pancytopenia and in blast differentiation. We propose that iron availability modulates myeloid cell commitment and that targeting this cellular differentiation pathway together with conventional differentiating agents provides new therapeutic modalities for AML.
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Affiliation(s)
- Celine Callens
- Centre National de la Recherche Scientifique UMR 8147, Paris 75015, France
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26
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Transbilayer (flip-flop
) lipid motion and lipid scrambling in membranes. FEBS Lett 2009; 584:1779-86. [DOI: 10.1016/j.febslet.2009.12.049] [Citation(s) in RCA: 162] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Accepted: 12/18/2009] [Indexed: 12/24/2022]
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27
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Okun E, Mattson MP, Arumugam TV. Involvement of Fc receptors in disorders of the central nervous system. Neuromolecular Med 2009; 12:164-78. [PMID: 19844812 DOI: 10.1007/s12017-009-8099-5] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2009] [Accepted: 10/07/2009] [Indexed: 01/09/2023]
Abstract
Immunoglobulins are proteins with a highly variable antigen-binding domain and a constant region (Fc domain) that binds to a cell surface receptor (FcR). Activation of FcRs in immune cells (lymphocytes, macrophages, and mast cells) triggers effector responses including cytokine production, phagocytosis, and degranulation. In addition to their roles in normal responses to infection or tissue injury, and in immune-related diseases, FcRs are increasingly recognized for their involvement in neurological disorders. One or more FcRs are expressed in microglia, astrocytes, oligodendrocytes, and neurons. Aberrant activation of FcRs in such neural cells may contribute to the pathogenesis of major neurodegenerative conditions including Alzheimer's disease, Parkinson's disease, ischemic stroke, and multiple sclerosis. On the other hand, FcRs may play beneficial roles in counteracting pathological processes; for e.g., FcRs may facilitate removal of amyloid peptides from the brain and so protect against Alzheimer's disease. Knowledge of the functions of FcRs in the nervous system in health and disease is leading to novel preventative and therapeutic strategies for stroke, Alzheimer's disease, and other neurological disorders.
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Affiliation(s)
- Eitan Okun
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, 251 Bayview Boulevard, Baltimore, MD 21224, USA
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Bateman A, Finn RD, Sims PJ, Wiedmer T, Biegert A, Söding J. Phospholipid scramblases and Tubby-like proteins belong to a new superfamily of membrane tethered transcription factors. Bioinformatics 2008; 25:159-62. [PMID: 19010806 PMCID: PMC2639001 DOI: 10.1093/bioinformatics/btn595] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Motivation: Phospholipid scramblases (PLSCRs) constitute a family of cytoplasmic membrane-associated proteins that were identified based upon their capacity to mediate a Ca2+-dependent bidirectional movement of phospholipids across membrane bilayers, thereby collapsing the normally asymmetric distribution of such lipids in cell membranes. The exact function and mechanism(s) of these proteins nevertheless remains obscure: data from several laboratories now suggest that in addition to their putative role in mediating transbilayer flip/flop of membrane lipids, the PLSCRs may also function to regulate diverse processes including signaling, apoptosis, cell proliferation and transcription. A major impediment to deducing the molecular details underlying the seemingly disparate biology of these proteins is the current absence of any representative molecular structures to provide guidance to the experimental investigation of their function. Results: Here, we show that the enigmatic PLSCR family of proteins is directly related to another family of cellular proteins with a known structure. The Arabidopsis protein At5g01750 from the DUF567 family was solved by X-ray crystallography and provides the first structural model for this family. This model identifies that the presumed C-terminal transmembrane helix is buried within the core of the PLSCR structure, suggesting that palmitoylation may represent the principal membrane anchorage for these proteins. The fold of the PLSCR family is also shared by Tubby-like proteins. A search of the PDB with the HHpred server suggests a common evolutionary ancestry. Common functional features also suggest that tubby and PLSCR share a functional origin as membrane tethered transcription factors with capacity to modulate phosphoinositide-based signaling. Contact:agb@sanger.ac.uk
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Affiliation(s)
- Alex Bateman
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, UK.
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Somerharju P, Virtanen JA, Cheng KH, Hermansson M. The superlattice model of lateral organization of membranes and its implications on membrane lipid homeostasis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1788:12-23. [PMID: 19007747 DOI: 10.1016/j.bbamem.2008.10.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2008] [Revised: 10/10/2008] [Accepted: 10/10/2008] [Indexed: 01/10/2023]
Abstract
Most biological membranes are extremely complex structures consisting of hundreds of different lipid and protein molecules. According to the famous fluid-mosaic model lipids and many proteins are free to diffuse very rapidly in the plane of the membrane. While such fast diffusion implies that different membrane lipids would be laterally randomly distributed, accumulating evidence indicates that in model and natural membranes the lipid components tend to adopt regular (superlattice-like) distributions. The superlattice model, put forward based on such evidence, is intriguing because it predicts that 1) there is a limited number of allowed compositions representing local minima in membrane free energy and 2) those energy minima could provide set-points for enzymes regulating membrane lipid compositions. Furthermore, the existence of a discrete number of allowed compositions could help to maintain organelle identity in the face of rapid inter-organelle membrane traffic.
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Affiliation(s)
- Pentti Somerharju
- Institute of Biomedicine, Department of Medical Biochemistry, University of Helsinki, Finland.
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