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Tamarit-Rodriguez J. Regulatory Role of Fatty Acid Metabolism on Glucose-Induced Changes in Insulin and Glucagon Secretion by Pancreatic Islet Cells. Int J Mol Sci 2024; 25:6052. [PMID: 38892240 PMCID: PMC11172437 DOI: 10.3390/ijms25116052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 05/21/2024] [Accepted: 05/26/2024] [Indexed: 06/21/2024] Open
Abstract
A detailed study of palmitate metabolism in pancreatic islets subject to different experimental conditions, like varying concentrations of glucose, as well as fed or starved conditions, has allowed us to explore the interaction between the two main plasma nutrients and its consequences on hormone secretion. Palmitate potentiates glucose-induced insulin secretion in a concentration-dependent manner, in a physiological range of both palmitate (0-2 mM) and glucose (6-20 mM) concentrations; at glucose concentrations lower than 6 mM, no metabolic interaction with palmitate was apparent. Starvation (48 h) increased islet palmitate oxidation two-fold, and the effect was resistant to its inhibition by glucose (6-20 mM). Consequently, labelled palmitate and glucose incorporation into complex lipids were strongly suppressed, as well as glucose-induced insulin secretion and its potentiation by palmitate. 2-bromostearate, a palmitate oxidation inhibitor, fully recovered the synthesis of complex lipids and insulin secretion. We concluded that palmitate potentiation of the insulin response to glucose is not attributable to its catabolic mitochondrial oxidation but to its anabolism to complex lipids: islet lipid biosynthesis is dependent on the uptake of plasma fatty acids and the supply of α-glycerol phosphate from glycolysis. Islet secretion of glucagon and somatostatin showed a similar dependence on palmitate anabolism as insulin. The possible mechanisms implicated in the metabolic coupling between glucose and palmitate were commented on. Moreover, possible mechanisms responsible for islet gluco- or lipotoxicity after a long-term stimulation of insulin secretion were also discussed. Our own data on the simultaneous stimulation of insulin, glucagon, and somatostatin by glucose, as well as their modification by 2-bromostearate in perifused rat islets, give support to the conclusion that increased FFA anabolism, rather than its mitochondrial oxidation, results in a potentiation of their stimulated release. Starvation, besides suppressing glucose stimulation of insulin secretion, also blocks the inhibitory effect of glucose on glucagon secretion: this suggests that glucagon inhibition might be an indirect or direct effect of insulin, but not of glucose. In summary, there seems to exist three mechanisms of glucagon secretion stimulation: 1. glucagon stimulation through the same secretion coupling mechanism as insulin, but in a different range of glucose concentrations (0 to 5 mM). 2. Direct or indirect inhibition by secreted insulin in response to glucose (5-20 mM). 3. Stimulation by increased FFA anabolism in glucose intolerance or diabetes in the context of hyperlipidemia, hyperglycemia, and hypo-insulinemia. These conclusions were discussed and compared with previous published data in the literature. Specially, we discussed the mechanism for inhibition of glucagon release by glucose, which was apparently contradictory with the secretion coupling mechanism of its stimulation.
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2
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Akefe IO, Saber SH, Matthews B, Venkatesh BG, Gormal RS, Blackmore DG, Alexander S, Sieriecki E, Gambin Y, Bertran-Gonzalez J, Vitale N, Humeau Y, Gaudin A, Ellis SA, Michaels AA, Xue M, Cravatt B, Joensuu M, Wallis TP, Meunier FA. The DDHD2-STXBP1 interaction mediates long-term memory via generation of saturated free fatty acids. EMBO J 2024; 43:533-567. [PMID: 38316990 PMCID: PMC10897203 DOI: 10.1038/s44318-024-00030-7] [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: 05/11/2023] [Revised: 12/06/2023] [Accepted: 12/14/2023] [Indexed: 02/07/2024] Open
Abstract
The phospholipid and free fatty acid (FFA) composition of neuronal membranes plays a crucial role in learning and memory, but the mechanisms through which neuronal activity affects the brain's lipid landscape remain largely unexplored. The levels of saturated FFAs, particularly of myristic acid (C14:0), strongly increase during neuronal stimulation and memory acquisition, suggesting the involvement of phospholipase A1 (PLA1) activity in synaptic plasticity. Here, we show that genetic ablation of the PLA1 isoform DDHD2 in mice dramatically reduces saturated FFA responses to memory acquisition across the brain. Furthermore, DDHD2 loss also decreases memory performance in reward-based learning and spatial memory models prior to the development of neuromuscular deficits that mirror human spastic paraplegia. Via pulldown-mass spectrometry analyses, we find that DDHD2 binds to the key synaptic protein STXBP1. Using STXBP1/2 knockout neurosecretory cells and a haploinsufficient STXBP1+/- mouse model of human early infantile encephalopathy associated with intellectual disability and motor dysfunction, we show that STXBP1 controls targeting of DDHD2 to the plasma membrane and generation of saturated FFAs in the brain. These findings suggest key roles for DDHD2 and STXBP1 in lipid metabolism and in the processes of synaptic plasticity, learning, and memory.
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Affiliation(s)
- Isaac O Akefe
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
- Academy for Medical Education, Medical School, The University of Queensland, 288 Herston Road, 4006, Brisbane, QLD, Australia
| | - Saber H Saber
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, St Lucia, QLD, 4072, Australia
| | - Benjamin Matthews
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Bharat G Venkatesh
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Rachel S Gormal
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Daniel G Blackmore
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Suzy Alexander
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Emma Sieriecki
- School of Medical Science, University of New South Wales, Randwick, NSW, 2052, Australia
- EMBL Australia, Single Molecule Node, University of New South Wales, Sydney, 2052, Australia
| | - Yann Gambin
- School of Medical Science, University of New South Wales, Randwick, NSW, 2052, Australia
- EMBL Australia, Single Molecule Node, University of New South Wales, Sydney, 2052, Australia
| | | | - Nicolas Vitale
- Institut des Neurosciences Cellulaires et Intégratives, UPR-3212 CNRS - Université de Strasbourg, Strasbourg, France
| | - Yann Humeau
- Interdisciplinary Institute for Neuroscience, CNRS UMR 5297, Université de Bordeaux, Bordeaux, France
| | - Arnaud Gaudin
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Sevannah A Ellis
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Alysee A Michaels
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX, USA
| | - Mingshan Xue
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Benjamin Cravatt
- The Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Merja Joensuu
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia.
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, St Lucia, QLD, 4072, Australia.
| | - Tristan P Wallis
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia.
| | - Frédéric A Meunier
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia.
- The School of Biomedical Sciences, The University of Queensland, St Lucia, QLD, 4072, Australia.
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3
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Del-Río-Robles JE, Tomás-Morales JA, Zavala-Barrera C, Castillo-Kauil A, García-Jiménez I, Vázquez-Prado J, Reyes-Cruz G. CaSR links endocytic and secretory pathways via MADD, a Rab11A effector that activates Rab27B. Cell Signal 2023; 111:110857. [PMID: 37604243 DOI: 10.1016/j.cellsig.2023.110857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 08/17/2023] [Accepted: 08/18/2023] [Indexed: 08/23/2023]
Abstract
Calcium sensing receptor (CaSR), a class C GPCR, regulates essential secretory pathways, involving communication between endocytic and secretory Rab GTPases, via still to be fully defined molecular mechanisms. To address how communication between endocytic and secretory vesicles occurs, we hypothesized that CaSR activates endocytic Rab11A-dependent effector pathways acting upstream of Rab27B-regulated secretion. We found that Rab11A is critical to promote Rab27B-dependent secretion of chemotactic and inflammatory factors, including IL-8, CCL2/MCP-1, and IL1-β, in response to CaSR stimulation. It also attenuates secretion of IL-6. The process is mediated by endosomal PI3-kinases, Vps34 and PI3KC2α, which promote Rab27B activation. Rab11A interacts with and activates MADD, a guanine exchange factor for Rab3, and Rab27A/B. Mechanistically, CaSR drives Rab11A-dependent coupling of recycling endosomes to secretory-vesicles via endosomal PI3K-mediated activation of a MADD/Rab27B pathway.
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Affiliation(s)
- Jorge Eduardo Del-Río-Robles
- Department of Cell Biology, Centro de Investigación y Estudios Avanzados del IPN (Cinvestav-IPN), Mexico City, Mexico
| | - Janik Adriana Tomás-Morales
- Department of Cell Biology, Centro de Investigación y Estudios Avanzados del IPN (Cinvestav-IPN), Mexico City, Mexico
| | - Cesar Zavala-Barrera
- Department of Cell Biology, Centro de Investigación y Estudios Avanzados del IPN (Cinvestav-IPN), Mexico City, Mexico
| | - Alejandro Castillo-Kauil
- Department of Cell Biology, Centro de Investigación y Estudios Avanzados del IPN (Cinvestav-IPN), Mexico City, Mexico
| | - Irving García-Jiménez
- Department of Cell Biology, Centro de Investigación y Estudios Avanzados del IPN (Cinvestav-IPN), Mexico City, Mexico
| | - José Vázquez-Prado
- Department of Pharmacology, Centro de Investigación y Estudios Avanzados del IPN (Cinvestav-IPN), Mexico City, Mexico
| | - Guadalupe Reyes-Cruz
- Department of Cell Biology, Centro de Investigación y Estudios Avanzados del IPN (Cinvestav-IPN), Mexico City, Mexico.
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Iyer DR, Venkatraman J, Tanguy E, Vitale N, Mahapatra NR. Chromogranin A and its derived peptides: potential regulators of cholesterol homeostasis. Cell Mol Life Sci 2023; 80:271. [PMID: 37642733 PMCID: PMC11072126 DOI: 10.1007/s00018-023-04908-3] [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: 03/03/2023] [Revised: 08/02/2023] [Accepted: 08/03/2023] [Indexed: 08/31/2023]
Abstract
Chromogranin A (CHGA), a member of the granin family of proteins, has been an attractive therapeutic target and candidate biomarker for several cardiovascular, neurological, and inflammatory disorders. The prominence of CHGA stems from the pleiotropic roles of several bioactive peptides (e.g., catestatin, pancreastatin, vasostatins) generated by its proteolytic cleavage and by their wide anatomical distribution. These peptides are emerging as novel modulators of cardiometabolic diseases that are often linked to high blood cholesterol levels. However, their impact on cholesterol homeostasis is poorly understood. The dynamic nature of cholesterol and its multitudinous roles in almost every aspect of normal body function makes it an integral component of metabolic physiology. A tightly regulated coordination of cholesterol homeostasis is imperative for proper functioning of cellular and metabolic processes. The deregulation of cholesterol levels can result in several pathophysiological states. Although studies till date suggest regulatory roles for CHGA and its derived peptides on cholesterol levels, the mechanisms by which this is achieved still remain unclear. This review aims to aggregate and consolidate the available evidence linking CHGA with cholesterol homeostasis in health and disease. In addition, we also look at common molecular regulatory factors (viz., transcription factors and microRNAs) which could govern the expression of CHGA and genes involved in cholesterol homeostasis under basal and pathological conditions. In order to gain further insights into the pathways mediating cholesterol regulation by CHGA/its derived peptides, a few prospective signaling pathways are explored, which could act as primers for future studies.
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Affiliation(s)
- Dhanya R Iyer
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, 600036, India
| | - Janani Venkatraman
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, 600036, India
| | - Emeline Tanguy
- Institut des Neurosciences Cellulaires et Intégratives, CNRS UPR 3212 and Université de Strasbourg, 5 Rue Blaise Pascal, 67000, Strasbourg, France
| | - Nicolas Vitale
- Institut des Neurosciences Cellulaires et Intégratives, CNRS UPR 3212 and Université de Strasbourg, 5 Rue Blaise Pascal, 67000, Strasbourg, France.
| | - Nitish R Mahapatra
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, 600036, India.
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5
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Jiang ZJ, Gong LW. The SphK1/S1P Axis Regulates Synaptic Vesicle Endocytosis via TRPC5 Channels. J Neurosci 2023; 43:3807-3824. [PMID: 37185099 PMCID: PMC10217994 DOI: 10.1523/jneurosci.1494-22.2023] [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: 08/03/2022] [Revised: 04/13/2023] [Accepted: 04/17/2023] [Indexed: 05/17/2023] Open
Abstract
Sphingosine-1-phosphate (S1P), a bioactive sphingolipid concentrated in the brain, is essential for normal brain functions, such as learning and memory and feeding behaviors. Sphingosine kinase 1 (SphK1), the primary kinase responsible for S1P production in the brain, is abundant within presynaptic terminals, indicating a potential role of the SphK1/S1P axis in presynaptic physiology. Altered S1P levels have been highlighted in many neurologic diseases with endocytic malfunctions. However, it remains unknown whether the SphK1/S1P axis may regulate synaptic vesicle endocytosis in neurons. The present study evaluates potential functions of the SphK1/S1P axis in synaptic vesicle endocytosis by determining effects of a dominant negative catalytically inactive SphK1. Our data for the first time identify a critical role of the SphK1/S1P axis in endocytosis in both neuroendocrine chromaffin cells and neurons from mice of both sexes. Furthermore, our Ca2+ imaging data indicate that the SphK1/S1P axis may be important for presynaptic Ca2+ increases during prolonged stimulations by regulating the Ca2+ permeable TRPC5 channels, which per se regulate synaptic vesicle endocytosis. Collectively, our data point out a critical role of the regulation of TRPC5 by the SphK1/S1P axis in synaptic vesicle endocytosis.SIGNIFICANCE STATEMENT Sphingosine kinase 1 (SphK1), the primary kinase responsible for brain sphingosine-1-phosphate (S1P) production, is abundant within presynaptic terminals. Altered SphK1/S1P metabolisms has been highlighted in many neurologic disorders with defective synaptic vesicle endocytosis. However, whether the SphK1/S1P axis may regulate synaptic vesicle endocytosis is unknown. Here, we identify that the SphK1/S1P axis regulates the kinetics of synaptic vesicle endocytosis in neurons, in addition to controlling fission-pore duration during single vesicle endocytosis in neuroendocrine chromaffin cells. The regulation of the SphK1/S1P axis in synaptic vesicle endocytosis is specific since it has a distinguished signaling pathway, which involves regulation of Ca2+ influx via TRPC5 channels. This discovery may provide novel mechanistic implications for the SphK1/S1P axis in brain functions under physiological and pathologic conditions.
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Affiliation(s)
- Zhong-Jiao Jiang
- Department of Biological Sciences, University of Illinois Chicago, Chicago, Illinois 60607
| | - Liang-Wei Gong
- Department of Biological Sciences, University of Illinois Chicago, Chicago, Illinois 60607
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6
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Fanani ML, Ambroggio EE. Phospholipases and Membrane Curvature: What Is Happening at the Surface? MEMBRANES 2023; 13:190. [PMID: 36837693 PMCID: PMC9965983 DOI: 10.3390/membranes13020190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/27/2023] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
In this revision work, we emphasize the close relationship between the action of phospholipases and the modulation of membrane curvature and curvature stress resulting from this activity. The alteration of the tridimensional structure of membranes upon the action of phospholipases is analyzed based on studies on model lipid membranes. The transient unbalance of both compositional and physical membrane properties between the hemilayers upon phospholipase activity lead to curvature tension and the catalysis of several membrane-related processes. Several proteins' membrane-bound and soluble forms are susceptible to regulation by the curvature stress induced by phospholipase action, which has important consequences in cell signaling. Additionally, the modulation of membrane fusion by phospholipase products regulates membrane dynamics in several cellular scenarios. We commented on vesicle fusion in the Golgi-endoplasmic system, synaptic vesicle fusion to the plasma membrane, viral membrane fusion to host cell plasma membrane and gametes membrane fusion upon acrosomal reaction. Furthermore, we explored the modulation of membrane fusion by the asymmetric adsorption of amphiphilic drugs. A deep understanding of the relevance of lipid membrane structure, particularly membrane curvature and curvature stress, on different cellular events leads to the challenge of its regulation, which may become a powerful tool for pharmacological therapy.
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Affiliation(s)
- María Laura Fanani
- Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba X5000HUA, Argentina
- Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), CONICET, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba X5000HUA, Argentina
| | - Ernesto Esteban Ambroggio
- Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba X5000HUA, Argentina
- Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), CONICET, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba X5000HUA, Argentina
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7
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Wolf A, Tanguy E, Wang Q, Gasman S, Vitale N. Phospholipase D and cancer metastasis: A focus on exosomes. Adv Biol Regul 2023; 87:100924. [PMID: 36272918 DOI: 10.1016/j.jbior.2022.100924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 09/30/2022] [Accepted: 10/10/2022] [Indexed: 03/01/2023]
Abstract
In mammals, phospholipase D (PLD) enzymes involve 6 isoforms, of which only three have established lipase activity to produce the signaling lipid phosphatidic acid (PA). This phospholipase activity has been postulated to contribute to cancer progression for over three decades now, but the exact mechanisms involved have yet to be uncovered. Indeed, using various models, an altered PLD activity has been proposed altogether to increase cell survival rate, promote angiogenesis, boost rapamycin resistance, and favor metastasis. Although for some part, the molecular pathways by which this increase in PA is pro-oncogenic are partially known, the pleiotropic functions of PA make it quite difficult to distinguish which among these simple signaling pathways is responsible for each of these PLD facets. In this review, we will describe an additional potential contribution of PA generated by PLD1 and PLD2 in the biogenesis, secretion, and uptake of exosomes. Those extracellular vesicles are now viewed as membrane vehicles that carry informative molecules able to modify the fate of receiving cells at distance from the original tumor to favor homing of metastasis. The perspectives for a better understanding of these complex role of PLDs will be discussed.
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Affiliation(s)
- Alexander Wolf
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Emeline Tanguy
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Qili Wang
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Stéphane Gasman
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Nicolas Vitale
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France.
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Rosenhouse-Dantsker A, Gazgalis D, Logothetis DE. PI(4,5)P 2 and Cholesterol: Synthesis, Regulation, and Functions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1422:3-59. [PMID: 36988876 DOI: 10.1007/978-3-031-21547-6_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) is the most abundant membrane phosphoinositide and cholesterol is an essential component of the plasma membrane (PM). Both lipids play key roles in a variety of cellular functions including as signaling molecules and major regulators of protein function. This chapter provides an overview of these two important lipids. Starting from a brief description of their structure, synthesis, and regulation, the chapter continues to describe the primary functions and signaling processes in which PI(4,5)P2 and cholesterol are involved. While PI(4,5)P2 and cholesterol can act independently, they often act in concert or affect each other's impact. The chapters in this volume on "Cholesterol and PI(4,5)P2 in Vital Biological Functions: From Coexistence to Crosstalk" focus on the emerging relationship between cholesterol and PI(4,5)P2 in a variety of biological systems and processes. In this chapter, the next section provides examples from the ion channel field demonstrating that PI(4,5)P2 and cholesterol can act via common mechanisms. The chapter ends with a discussion of future directions.
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Affiliation(s)
| | - Dimitris Gazgalis
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Bouvé College of Health Sciences, Northeastern University, Boston, MA, USA
| | - Diomedes E Logothetis
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Bouvé College of Health Sciences, Northeastern University, Boston, MA, USA
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Ragaller F, Andronico L, Sykora J, Kulig W, Rog T, Urem YB, Abhinav, Danylchuk DI, Hof M, Klymchenko A, Amaro M, Vattulainen I, Sezgin E. Dissecting the mechanisms of environment sensitivity of smart probes for quantitative assessment of membrane properties. Open Biol 2022; 12:220175. [PMID: 36099931 PMCID: PMC9470265 DOI: 10.1098/rsob.220175] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The plasma membrane, as a highly complex cell organelle, serves as a crucial platform for a multitude of cellular processes. Its collective biophysical properties are largely determined by the structural diversity of the different lipid species it accommodates. Therefore, a detailed investigation of biophysical properties of the plasma membrane is of utmost importance for a comprehensive understanding of biological processes occurring therein. During the past two decades, several environment-sensitive probes have been developed and become popular tools to investigate membrane properties. Although these probes are assumed to report on membrane order in similar ways, their individual mechanisms remain to be elucidated. In this study, using model membrane systems, we characterized the probes Pro12A, NR12S and NR12A in depth and examined their sensitivity to parameters with potential biological implications, such as the degree of lipid saturation, double bond position and configuration (cis versus trans), phospholipid headgroup and cholesterol content. Applying spectral imaging together with atomistic molecular dynamics simulations and time-dependent fluorescent shift analyses, we unravelled individual sensitivities of these probes to different biophysical properties, their distinct localizations and specific relaxation processes in membranes. Overall, Pro12A, NR12S and NR12A serve together as a toolbox with a wide range of applications allowing to select the most appropriate probe for each specific research question.
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Affiliation(s)
- Franziska Ragaller
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, 17165 Solna, Sweden
| | - Luca Andronico
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, 17165 Solna, Sweden
| | - Jan Sykora
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, 18223 Prague 8, Czech Republic
| | - Waldemar Kulig
- Department of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| | - Tomasz Rog
- Department of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| | - Yagmur Balim Urem
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, 17165 Solna, Sweden
| | - Abhinav
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, 18223 Prague 8, Czech Republic
| | - Dmytro I Danylchuk
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, 74 Route du Rhin, 67401 Illkirch, France
| | - Martin Hof
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, 18223 Prague 8, Czech Republic
| | - Andrey Klymchenko
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, 74 Route du Rhin, 67401 Illkirch, France
| | - Mariana Amaro
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, 18223 Prague 8, Czech Republic
| | - Ilpo Vattulainen
- Department of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| | - Erdinc Sezgin
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, 17165 Solna, Sweden
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10
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Abhinandan K, Sankaranarayanan S, Macgregor S, Goring DR, Samuel MA. Cell-cell signaling during the Brassicaceae self-incompatibility response. TRENDS IN PLANT SCIENCE 2022; 27:472-487. [PMID: 34848142 DOI: 10.1016/j.tplants.2021.10.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 10/15/2021] [Accepted: 10/26/2021] [Indexed: 06/13/2023]
Abstract
Self-incompatibility (SI) is a mechanism that many plant families employ to prevent self-fertilization. In the Brassicaceae, the S-haplotype-specific interaction of the pollen-borne ligand, and a stigma-specific receptor protein kinase triggers a signaling cascade that culminates in the rejection of self-pollen. While the upstream molecular components at the receptor level of the signaling pathway have been extensively studied, the intracellular responses beyond receptor activation were not as well understood. Recent research has uncovered several key molecules and signaling events that operate in concert for the manifestation of the self-incompatible responses in Brassicaceae stigmas. Here, we review the recent discoveries in both the compatible and self-incompatible pathways and provide new perspectives on the early stages of Brassicaceae pollen-pistil interactions.
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Affiliation(s)
- Kumar Abhinandan
- University of Calgary, Department of Biological Sciences, Calgary, Alberta T2N 1N4, Canada; 20/20 Seed Labs Inc., Nisku, Alberta T9E 7N5, Canada
| | | | - Stuart Macgregor
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario M5S 3B2, Canada
| | - Daphne R Goring
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario M5S 3B2, Canada
| | - Marcus A Samuel
- University of Calgary, Department of Biological Sciences, Calgary, Alberta T2N 1N4, Canada.
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11
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Cherkashin AP, Rogachevskaja OA, Kabanova NV, Kotova PD, Bystrova MF, Kolesnikov SS. Taste Cells of the Type III Employ CASR to Maintain Steady Serotonin Exocytosis at Variable Ca 2+ in the Extracellular Medium. Cells 2022; 11:cells11081369. [PMID: 35456048 PMCID: PMC9030112 DOI: 10.3390/cells11081369] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 04/07/2022] [Accepted: 04/11/2022] [Indexed: 12/17/2022] Open
Abstract
Type III taste cells are the only taste bud cells which express voltage-gated (VG) Ca2+ channels and employ Ca2+-dependent exocytosis to release neurotransmitters, particularly serotonin. The taste bud is a tightly packed cell population, wherein extracellular Ca2+ is expected to fluctuate markedly due to the electrical activity of taste cells. It is currently unclear whether the Ca2+ entry-driven synapse in type III cells could be reliable enough at unsteady extracellular Ca2. Here we assayed depolarization-induced Ca2+ signals and associated serotonin release in isolated type III cells at varied extracellular Ca2+. It turned out that the same depolarizing stimulus elicited invariant Ca2+ signals in type III cells irrespective of bath Ca2+ varied within 0.5–5 mM. The serotonin release from type III cells was assayed with the biosensor approach by using HEK-293 cells co-expressing the recombinant 5-HT4 receptor and genetically encoded cAMP sensor Pink Flamindo. Consistently with the weak Ca2+ dependence of intracellular Ca2+ transients produced by VG Ca2+ entry, depolarization-triggered serotonin secretion varied negligibly with bath Ca2+. The evidence implicated the extracellular Ca2+-sensing receptor in mediating the negative feedback mechanism that regulates VG Ca2+ entry and levels off serotonin release in type III cells at deviating Ca2+ in the extracellular medium.
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12
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Yue Q, Wang K, Guan M, Zhao Z, Li X, Yu P, Mao L. Single-Vesicle Electrochemistry Reveals Sex Difference in Vesicular Storage and Release of Catecholamine. Angew Chem Int Ed Engl 2022; 61:e202117596. [PMID: 35112448 DOI: 10.1002/anie.202117596] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Indexed: 12/17/2022]
Abstract
Quantitative measurements of sex difference in vesicle chemistry (i.e., chemical storage and release) at the single-vesicle level are essential to understand sex differences in cognitive behaviors; however, such measurements are very challenging to conventional analytical methods. By using single-vesicle electrochemistry, we find the duration of single exocytotic events of chromaffin cells prepared from male rats is statistically longer than that from female rats, leading to more neurotransmitter released in the male group. Further analysis reveals that a higher percentage of vesicles in the female group release part of the neurotransmitter, i.e., partial release, during exocytosis than that in male group. This sex dimorphism in neurotransmitter release in exocytosis might relate to the sex difference in the expression of voltage-dependent calcium channels and membrane lipid composition. Our finding offers the first experimental evidence that sex dimorphism even exists in vesicle chemistry, providing a brand new viewpoint for understanding the sex dimorphism in exocytosis.
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Affiliation(s)
- Qingwei Yue
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Kai Wang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China
| | - Ming Guan
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China
| | - Zhenwen Zhao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xianchan Li
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China
| | - Ping Yu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lanqun Mao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China.,College of Chemistry, Beijing Normal University, Beijing, 100875, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
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13
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Yue Q, Wang K, Guan M, Zhao Z, Li X, Yu P, Mao L. Single‐Vesicle Electrochemistry Reveals Sex Difference in Vesicular Storage and Release of Catecholamine. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202117596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Qingwei Yue
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Kai Wang
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
| | - Ming Guan
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
| | - Zhenwen Zhao
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Xianchan Li
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
| | - Ping Yu
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Lanqun Mao
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- College of Chemistry Beijing Normal University Beijing 100875 China
- University of Chinese Academy of Sciences Beijing 100049 China
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14
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Das UN. Arachidonic Acid as Mechanotransducer of Renin Cell Baroreceptor. Nutrients 2022; 14:nu14040749. [PMID: 35215399 PMCID: PMC8874622 DOI: 10.3390/nu14040749] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 01/31/2022] [Accepted: 02/02/2022] [Indexed: 11/16/2022] Open
Abstract
For normal maintenance of blood pressure and blood volume a well-balanced renin-angiotensin-aldosterone system (RAS) is necessary. For this purpose, renin is secreted as the situation demands by the juxtaglomerular cells (also called as granular cells) that are in the walls of the afferent arterioles. Juxtaglomerular cells can sense minute changes in the blood pressure and blood volume and accordingly synthesize, store, and secrete appropriate amounts of renin. Thus, when the blood pressure and blood volume are decreased JGA cells synthesize and secrete higher amounts of renin and when the blood pressure and blood volume is increased the synthesis and secretion of renin is decreased such that homeostasis is restored. To decipher this important function, JGA cells (renin cells) need to sense and transmit the extracellular physical forces to their chromatin to control renin gene expression for appropriate renin synthesis. The changes in perfusion pressure are sensed by Integrin β1 that is transmitted to the renin cell’s nucleus via lamin A/C that produces changes in the architecture of the chromatin. This results in an alteration (either increase or decrease) in renin gene expression. Cell membrane is situated in an unique location since all stimuli need to be transmitted to the cell nucleus and messages from the DNA to the cell external environment can be conveyed only through it. This implies that cell membrane structure and integrity is essential for all cellular functions. Cell membrane is composed to proteins and lipids. The lipid components of the cell membrane regulate its (cell membrane) fluidity and the way the messages are transmitted between the cell and its environment. Of all the lipids present in the membrane, arachidonic acid (AA) forms an important constituent. In response to pressure and other stimuli, cellular and nuclear shape changes occur that render nucleus to act as an elastic mechanotransducer that produces not only changes in cell shape but also in its dynamic behavior. Cell shape changes in response to external pressure(s) result(s) in the activation of cPLA2 (cytosolic phospholipase 2)-AA pathway that stretches to recruit myosin II which produces actin-myosin cytoskeleton contractility. Released AA can undergo peroxidation and peroxidized AA binds to DNA to regulate the expression of several genes. Alterations in the perfusion pressure in the afferent arterioles produces parallel changes in the renin cell membrane leading to changes in renin release. AA and its metabolic products regulate not only the release of renin but also changes in the vanilloid type 1 (TRPV1) expression in renal sensory nerves. Thus, AA and its metabolites function as intermediate/mediator molecules in transducing changes in perfusion and mechanical pressures that involves nuclear mechanotransduction mechanism. This mechanotransducer function of AA has relevance to the synthesis and release of insulin, neurotransmitters, and other soluble mediators release by specialized and non-specialized cells. Thus, AA plays a critical role in diseases such as diabetes mellitus, hypertension, atherosclerosis, coronary heart disease, sepsis, lupus, rheumatoid arthritis, and cancer.
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Affiliation(s)
- Undurti N Das
- UND Life Sciences, 2221 NW 5th St., Battle Ground, WA 98604, USA
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15
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Hu K, Le Vo KL, Hatamie A, Ewing AG. Quantifying Intracellular Single Vesicular Catecholamine Concentration with Open Carbon Nanopipettes to Unveil the Effect of L‐DOPA on Vesicular Structure. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202113406] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Keke Hu
- Department of Chemistry and Molecular Biology University of Gothenburg Kemivägen 10 41296 Gothenburg Sweden
| | - Kim Long Le Vo
- Department of Chemistry and Molecular Biology University of Gothenburg Kemivägen 10 41296 Gothenburg Sweden
| | - Amir Hatamie
- Department of Chemistry and Molecular Biology University of Gothenburg Kemivägen 10 41296 Gothenburg Sweden
| | - Andrew G. Ewing
- Department of Chemistry and Molecular Biology University of Gothenburg Kemivägen 10 41296 Gothenburg Sweden
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16
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Tanguy E, Wolf A, Wang Q, Chasserot-Golaz S, Ory S, Gasman S, Vitale N. Phospholipase D1-generated phosphatidic acid modulates secretory granule trafficking from biogenesis to compensatory endocytosis in neuroendocrine cells. Adv Biol Regul 2021; 83:100844. [PMID: 34876384 DOI: 10.1016/j.jbior.2021.100844] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/22/2021] [Accepted: 11/24/2021] [Indexed: 11/16/2022]
Abstract
Calcium-regulated exocytosis is a multi-step process that allows specialized secretory cells to release informative molecules such as neurotransmitters, neuropeptides, and hormones for intercellular communication. The biogenesis of secretory vesicles from the Golgi cisternae is followed by their transport towards the cell periphery and their docking and fusion to the exocytic sites of the plasma membrane allowing release of vesicular content. Subsequent compensatory endocytosis of the protein and lipidic constituents of the vesicles maintains cell homeostasis. Despite the fact that lipids represent the majority of membrane constituents, little is known about their contribution to these processes. Using a combination of electrochemical measurement of single chromaffin cell catecholamine secretion and electron microscopy of roof-top membrane sheets associated with genetic, silencing and pharmacological approaches, we recently reported that diverse phosphatidic acid (PA) species regulates catecholamine release efficiency by controlling granule docking and fusion kinetics. The enzyme phospholipase D1 (PLD1), producing PA from phosphatidylcholine, seems to be the major responsible of these effects in this model. Here, we extended this work using spinning disk confocal microscopy showing that inhibition of PLD activity also reduced the velocity of granules undergoing a directed motion. Furthermore, a dopamine β-hydroxylase (DβH) internalization assay revealed that PA produced by PLD is required for an optimal recovery of vesicular membrane content by compensatory endocytosis. Thus, among numerous roles that have been attributed to PA our work gives core to the key regulatory role in secretion that has been proposed in different cell models. Few leads to explain these multiple functions of PA along the secretory pathway are discussed.
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Affiliation(s)
- Emeline Tanguy
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000, Strasbourg, France
| | - Alexander Wolf
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000, Strasbourg, France
| | - Qili Wang
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000, Strasbourg, France
| | - Sylvette Chasserot-Golaz
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000, Strasbourg, France
| | - Stéphane Ory
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000, Strasbourg, France
| | - Stéphane Gasman
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000, Strasbourg, France
| | - Nicolas Vitale
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000, Strasbourg, France.
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17
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Hu K, Le Vo KL, Hatamie A, Ewing AG. Quantifying Intracellular Single Vesicular Catecholamine Concentration with Open Carbon Nanopipettes to Unveil the Effect of L-DOPA on Vesicular Structure. Angew Chem Int Ed Engl 2021; 61:e202113406. [PMID: 34734466 PMCID: PMC9299131 DOI: 10.1002/anie.202113406] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Indexed: 12/03/2022]
Abstract
Understanding the regulatory mechanisms of exocytosis is essential for uncovering the pathologies of neuronal disorders and developing related pharmaceuticals. In this work intracellular vesicle impact electrochemical cytometry (IVIEC) measurements with different‐sized (50–500 nm radius) open carbon nanopipettes (CNPs) were performed to quantify the vesicular content and release kinetics of specific vesicle populations grouped by orifice sizes. Intracellular vesicles with radius below 100 nm were captured and narrowed between 50 and 100 nm. On the basis of this, single vesicular catecholamine concentrations in the intracellular environment were quantified as 0.23–1.1 M. Our results with L‐3,4‐dihydroxyphenylalanine (L‐DOPA)‐exposure indicate that L‐DOPA regulates exocytosis by increasing the dense core size and vesicular content while catecholamine concentrations did not show obvious alterations. These were all achieved simultaneously and relatively noninvasively with open CNPs.
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Affiliation(s)
- Keke Hu
- Department of Chemistry and Molecular Biology, University of Gothenburg, Kemivägen 10, 41296, Gothenburg, Sweden
| | - Kim Long Le Vo
- Department of Chemistry and Molecular Biology, University of Gothenburg, Kemivägen 10, 41296, Gothenburg, Sweden
| | - Amir Hatamie
- Department of Chemistry and Molecular Biology, University of Gothenburg, Kemivägen 10, 41296, Gothenburg, Sweden
| | - Andrew G Ewing
- Department of Chemistry and Molecular Biology, University of Gothenburg, Kemivägen 10, 41296, Gothenburg, Sweden
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18
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Abdullah M, Nakamura T, Ferdous T, Gao Y, Chen Y, Zou K, Michikawa M. Cholesterol Regulates Exosome Release in Cultured Astrocytes. Front Immunol 2021; 12:722581. [PMID: 34721384 PMCID: PMC8551362 DOI: 10.3389/fimmu.2021.722581] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 09/23/2021] [Indexed: 01/08/2023] Open
Abstract
Exosomes are vesicles secreted by various kinds of cells, and they are rich in cholesterol, sphingomyelin (SM), phosphatidylcholine, and phosphatidylserine. Although cellular sphingolipid-mediated exosome release has been reported, the involvement of other lipid components of cell membranes in the regulation of exosome release is poorly understood. Here, we show that the level of exosome release into conditioned media is significantly reduced in cultured astrocytes prepared from apolipoprotein E (ApoE) knock-out mice when compared to those prepared from wild-type (WT) mice. The reduced level of exosome release was accompanied by elevated levels of cellular cholesterol. The addition of cholesterol to WT astrocytes significantly increased the cellular cholesterol levels and reduced exosome release. PI3K/Akt phosphorylation was enhanced in ApoE-deficient and cholesterol-treated WT astrocytes. In contrast, the depletion of cholesterol in ApoE-deficient astrocytes due to treatment with β-cyclodextrin recovered the exosome release level to a level similar to that in WT astrocytes. In addition, the reduced levels of exosome release due to the addition of cholesterol recovered to the control levels after treatment with a PI3K inhibitor (LY294002). The cholesterol-dependent regulation of exosome release was also confirmed by in vivo experiments; that is, exosome levels were significantly reduced in the CSF and blood serum of WT mice that were fed a high-fat diet and had increased cholesterol levels when compared to those in WT mice that were fed a normal diet. These results suggest that exosome release is regulated by cellular cholesterol via stimulation of the PI3K/Akt signal pathway.
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Affiliation(s)
- Mohammad Abdullah
- Department of Biochemistry, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Tomohisa Nakamura
- Department of Biochemistry, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Taslima Ferdous
- Department of Biochemistry, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Yuan Gao
- Department of Biochemistry, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Yuxin Chen
- Department of Biochemistry, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Kun Zou
- Department of Biochemistry, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Makoto Michikawa
- Department of Biochemistry, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
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19
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Galkina OV, Vetrovoy OV, Eschenko ND. The Role of Lipids in Implementing Specific Functions in the Central Nervous System. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2021. [DOI: 10.1134/s1068162021050253] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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20
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Kassas N, Fouillen L, Gasman S, Vitale N. A Lipidomics Approach to Measure Phosphatidic Acid Species in Subcellular Membrane Fractions Obtained from Cultured Cells. Bio Protoc 2021; 11:e4066. [PMID: 34263007 DOI: 10.21769/bioprotoc.4066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 03/26/2021] [Indexed: 11/02/2022] Open
Abstract
Over the last decade, lipids have emerged as possessing an ever-increasing number of key functions, especially in membrane trafficking. For instance, phosphatidic acid (PA) has been proposed to play a critical role in different steps along the secretory pathway or during phagocytosis. To further investigate in detail the precise nature of PA activities, we need to identify the organelles in which PA is synthesized and the PA subspecies involved in these biological functions. Indeed, PA, like all phospholipids, has a large variety based on its fatty acid composition. The recent development of PA sensors has helped us to follow intracellular PA dynamics but has failed to provide information on individual PA species. Here, we describe a method for the subcellular fractionation of RAW264.7 macrophages that allows us to obtain membrane fractions enriched in specific organelles based on their density. Lipids from these membrane fractions are precipitated and subsequently processed by advanced mass spectrometry-based lipidomics analysis to measure the levels of different PA species based on their fatty acyl chain composition. This approach revealed the presence of up to 50 different species of PA in cellular membranes, opening up the possibility that a single class of phospholipid could play multiple functions in any given organelle. This protocol can be adapted or modified and used for the evaluation of other intracellular membrane compartments or cell types of interest.
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Affiliation(s)
- Nawal Kassas
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, 67000 Strasbourg, France
| | - Laetitia Fouillen
- Laboratoire de Biogénèse Membranaire, UMR-5200 Centre National de la Recherche Scientifique, Plateforme Métabolome, Université de Bordeaux; 33883 Villenave D'Ornon, France
| | - Stéphane Gasman
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, 67000 Strasbourg, France
| | - Nicolas Vitale
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, 67000 Strasbourg, France
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21
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Binotti B, Jahn R, Pérez-Lara Á. An overview of the synaptic vesicle lipid composition. Arch Biochem Biophys 2021; 709:108966. [PMID: 34139199 DOI: 10.1016/j.abb.2021.108966] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 06/10/2021] [Accepted: 06/10/2021] [Indexed: 11/29/2022]
Abstract
Chemical neurotransmission is the major mechanism of neuronal communication. Neurotransmitters are released from secretory organelles, the synaptic vesicles (SVs) via exocytosis into the synaptic cleft. Fusion of SVs with the presynaptic plasma membrane is balanced by endocytosis, thus maintaining the presynaptic membrane at steady-state levels. The protein machineries responsible for exo- and endocytosis have been extensively investigated. In contrast, less is known about the role of lipids in synaptic transmission and how the lipid composition of SVs is affected by dynamic exo-endocytotic cycling. Here we summarize the current knowledge about the composition, organization, and function of SV membrane lipids. We also cover lipid biogenesis and maintenance during the synaptic vesicle cycle.
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Affiliation(s)
- Beyenech Binotti
- Department of Biochemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Reinhard Jahn
- Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry, Am Faßberg 11, 37077, Göttingen, Germany.
| | - Ángel Pérez-Lara
- Department of Physical Chemistry, University of Granada, Campus Universitario de Cartuja, 18071, Granada, Spain.
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22
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Phospholipase Signaling in Breast Cancer. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021. [PMID: 33983572 DOI: 10.1007/978-981-32-9620-6_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/23/2023]
Abstract
Breast cancer progression results from subversion of multiple intra- or intercellular signaling pathways in normal mammary tissues and their microenvironment, which have an impact on cell differentiation, proliferation, migration, and angiogenesis. Phospholipases (PLC, PLD and PLA) are essential mediators of intra- and intercellular signaling. They hydrolyze phospholipids, which are major components of cell membrane that can generate many bioactive lipid mediators, such as diacylglycerol, phosphatidic acid, lysophosphatidic acid, and arachidonic acid. Enzymatic processing of phospholipids by phospholipases converts these molecules into lipid mediators that regulate multiple cellular processes, which in turn can promote breast cancer progression. Thus, dysregulation of phospholipases contributes to a number of human diseases, including cancer. This review describes how phospholipases regulate multiple cancer-associated cellular processes, and the interplay among different phospholipases in breast cancer. A thorough understanding of the breast cancer-associated signaling networks of phospholipases is necessary to determine whether these enzymes are potential targets for innovative therapeutic strategies.
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23
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Abstract
α-Synuclein (α-syn) is a key protein in the etiology of Parkinson's disease. In a disease state, α-syn accumulates as insoluble amyloid fibrils enriched in β-sheet structure. However, in its functional state, α-syn adopts an amphipathic helix upon membrane association and plays a role in synaptic vesicle docking, fusion, and clustering. In this Account, we describe our contributions made in the past decade toward developing a molecular understanding of α-syn membrane interactions, which are crucial for function and have pathological implications. Three topics are covered: α-syn membrane binding probed by neutron reflectometry (NR), the effects of membrane on α-syn amyloid formation, and interactions of α-syn with cellular membranes.NR offers a unique perspective by providing direct measurements of protein penetration depth. By the use of segmentally deuterated α-syn generated through native chemical ligation, the spatial resolution of specific membrane-bound polypeptide regions was determined by NR. Additionally, we used NR to characterize the membrane-bound complex of α-syn and glucocerebrosidase, a lysosomal hydrolase whose mutations are a common genetic risk factor for Parkinson's disease. Although phosphatidylcholine (PC) is the most abundant lipid species in mammalian cells, interactions of PC with α-syn have been largely ignored because they are substantially weaker compared with the electrostatically driven binding of negatively charged lipids. We discovered that α-syn tubulates zwitterionic PC membranes, which is likely related to its involvement in synaptic vesicle fusion by stabilization of membrane curvature. Interestingly, PC lipid tubules inhibit amyloid formation, in contrast to anionic phosphatidylglycerol lipid tubules, which stimulate protein aggregation. We also found that membrane fluidity influences the propensity of α-synuclein amyloid formation. Most recently, we obtained direct evidence of binding of α-syn to exocytic sites on intact cellular membranes using a method called cellular unroofing. This method provides direct access to the cytosolic plasma membrane. Importantly, measurements of fluorescence lifetime distributions revealed that α-syn is more conformationally dynamic at the membrane interface than previously appreciated. This exquisite responsiveness to specific lipid composition and membrane topology is important for both its physiological and pathological functions. Collectively, our work has provided insights into the effects of the chemical nature of phospholipid headgroups on the interplay among membrane remodeling, protein structure, and α-syn amyloid formation.
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Affiliation(s)
- Upneet Kaur
- Laboratory of Protein Conformation and Dynamics, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Jennifer C. Lee
- Laboratory of Protein Conformation and Dynamics, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, United States
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24
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Delavoie F, Royer C, Gasman S, Vitale N, Chasserot-Golaz S. Transmission Electron Microscopy and Tomography on Plasma Membrane Sheets to Study Secretory Docking. Methods Mol Biol 2021; 2233:301-309. [PMID: 33222143 DOI: 10.1007/978-1-0716-1044-2_20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
To study the formation and the architecture of exocytotic site, we generated plasma membrane (PM) sheets on electron microscopy grids to visualize the membrane organization and quantitatively analyze distributions of specific proteins and lipids. This technique allows observing the cytoplasmic face of the plasma membrane by transmission electron microscope. The principle of this approach relies on application of mechanical forces to break open cells. The exposed inner membrane surface can then be visualized with different electron-dense colorations, and specific proteins or lipids can be detected with gold-conjugated probes. Moreover, the membrane sheets are sufficiently resistant to support automated acquisition of multiple-tilt projections, and thus electron tomography allows to obtain three-dimensional (3D) ultrastructural images of secretory granule docked to the plasma membrane.
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Affiliation(s)
- Franck Delavoie
- Centre National de la Recherche Scientifique, Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative, Université de Toulouse, Toulouse, France
| | - Cathy Royer
- Plateforme Imagerie In Vitro, Neuropôle de Strasbourg, Strasbourg, France
| | - Stéphane Gasman
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Nicolas Vitale
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Sylvette Chasserot-Golaz
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France.
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Tanguy E, Wolf A, Montero-Hadjadje M, Gasman S, Bader MF, Vitale N. Phosphatidic acid: Mono- and poly-unsaturated forms regulate distinct stages of neuroendocrine exocytosis. Adv Biol Regul 2020; 79:100772. [PMID: 33288473 DOI: 10.1016/j.jbior.2020.100772] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 11/16/2020] [Accepted: 11/25/2020] [Indexed: 10/22/2022]
Abstract
Lipids have emerged as important actors in an ever-growing number of key functions in cell biology over the last few years. Among them, glycerophospholipids are major constituents of cellular membranes. Because of their amphiphilic nature, phospholipids form lipid bilayers that are particularly useful to isolate cellular content from the extracellular medium, but also to define intracellular compartments. Interestingly, phospholipids come in different flavors based on their fatty acyl chain composition. Indeed, lipidomic analyses have revealed the presence in cellular membranes of up to 50 different species of an individual class of phospholipid, opening the possibility of multiple functions for a single class of phospholipid. In this review we will focus on phosphatidic acid (PA), the simplest phospholipid, that plays both structural and signaling functions. Among the numerous roles that have been attributed to PA, a key regulatory role in secretion has been proposed in different cell models. We review here the evidences that support the idea that mono- and poly-unsaturated PA control distinct steps in hormone secretion from neuroendocrine cells.
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Affiliation(s)
- Emeline Tanguy
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
| | - Alexander Wolf
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
| | - Maité Montero-Hadjadje
- Normandie Univ, UNIROUEN, INSERM, U1239, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale de Normandie, 76000, Rouen, France
| | - Stéphane Gasman
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
| | - Marie-France Bader
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
| | - Nicolas Vitale
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France.
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Light-induced lipid mixing implies a causal role of lipid splay in membrane fusion. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183438. [PMID: 32781156 DOI: 10.1016/j.bbamem.2020.183438] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 07/31/2020] [Accepted: 07/31/2020] [Indexed: 11/23/2022]
Abstract
The fusion of lipid membranes is central to many biological processes and requires substantial structural reorganization of lipids brought about by the action of fusogenic proteins. Previous molecular dynamics simulations have suggested that splayed lipids, whose tails transiently contact the headgroup region of the bilayer, initiate lipid mixing. Here, we explore the lipid splay hypothesis experimentally. We show that the light-induced trans/cis conversion of the azobenzene-based tail of a model lipid molecule enhances the probability by which its own acyl chains, or the acyl chains of the host lipid, transiently contact the lipid headgroup in a liposomal bilayer. At the same time, the trans/cis conversion triggers lipid mixing of sonicated or extruded liposomes, without requiring fusogenic proteins. This establishes a causal relationship between lipid splay and membrane fusion.
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Chalapathi D, Padmanabhan S, Manjithaya R, Narayana C. Surface-Enhanced Raman Spectroscopy as a Tool for Distinguishing Extracellular Vesicles under Autophagic Conditions: A Marker for Disease Diagnostics. J Phys Chem B 2020; 124:10952-10960. [PMID: 33095582 DOI: 10.1021/acs.jpcb.0c06910] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Extracellular vesicles (EVs) laden with lipids, proteins, DNA, and micro-RNAs play important biological functions in intercellular communication and have pivotal roles in pathophysiological conditions. Characterization of the EVs has always been a multistep process involving large volumes, and they are heterogeneous in size and properties. A multitude of approaches is used to distinguish the EVs. Here, we report simple citrate reduced silver nanoparticles assisted surface-enhanced Raman spectroscopy (SERS) as a tool to distinguish EVs extracted from several cell lines isolated under autophagic conditions (nitrogen starvation). This study is the first report of its kind in characterizing EVs from cells under autophagic conditions using SERS. We used two cancerous cell lines, HeLa, its corresponding autophagy-deficient cell line (Atg5-/-), and a noncancerous cell line, HEK293, to isolate EVs. Our study helps in the facile detection and differentiation of EVs isolated between two closely related human cell lines that differ by their autophagic ability. The principal component analysis (PCA) of the SERS spectra of these EVs consistently showed the presence of distinct chemical compositions of the EVs. SERS of EVs can help in probing more into the molecular level information from EVs and could become a powerful tool once coupled with improved microscopy techniques for diagnosis and therapy.
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Nguyen TTN, Koerdt SN, Gerke V. Plasma membrane phosphatidylinositol (4,5)-bisphosphate promotes Weibel-Palade body exocytosis. Life Sci Alliance 2020; 3:3/11/e202000788. [PMID: 32826291 PMCID: PMC7442956 DOI: 10.26508/lsa.202000788] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 08/14/2020] [Accepted: 08/14/2020] [Indexed: 01/26/2023] Open
Abstract
Phosphatidylinositol (4,5)-bisphosphate transiently accumulates at sites of Weibel–Palade body–plasma membrane fusion and promotes agonist-evoked exocytosis of endothelial von-Willebrand factor. Weibel–Palade bodies (WPB) are specialized secretory organelles of endothelial cells that control vascular hemostasis by regulated, Ca2+-dependent exocytosis of the coagulation-promoting von-Willebrand factor. Some proteins of the WPB docking and fusion machinery have been identified but a role of membrane lipids in regulated WPB exocytosis has so far remained elusive. We show here that the plasma membrane phospholipid composition affects Ca2+-dependent WPB exocytosis and von-Willebrand factor release. Phosphatidylinositol (4,5)-bisphosphate [PI(4,5)P2] becomes enriched at WPB–plasma membrane contact sites at the time of fusion, most likely downstream of phospholipase D1-mediated production of phosphatidic acid (PA) that activates phosphatidylinositol 4-phosphate (PI4P) 5-kinase γ. Depletion of plasma membrane PI(4,5)P2 or down-regulation of PI4P 5-kinase γ interferes with histamine-evoked and Ca2+-dependent WPB exocytosis and a mutant PI4P 5-kinase γ incapable of binding PA affects WPB exocytosis in a dominant-negative manner. This indicates that a unique PI(4,5)P2-rich environment in the plasma membrane governs WPB fusion possibly by providing interaction sites for WPB-associated docking factors.
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Affiliation(s)
- Tu Thi Ngoc Nguyen
- Institute of Medical Biochemistry, Center for Molecular Biology of Inflammation, University of Münster, Münster, Germany
| | - Sophia N Koerdt
- Institute of Medical Biochemistry, Center for Molecular Biology of Inflammation, University of Münster, Münster, Germany
| | - Volker Gerke
- Institute of Medical Biochemistry, Center for Molecular Biology of Inflammation, University of Münster, Münster, Germany
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29
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Stephens DC, Powell TW, Taraska JW, Harris DA. Imaging the rapid yet transient accumulation of regulatory lipids, lipid kinases, and protein kinases during membrane fusion, at sites of exocytosis of MMP-9 in MCF-7 cells. Lipids Health Dis 2020; 19:195. [PMID: 32829709 PMCID: PMC7444259 DOI: 10.1186/s12944-020-01374-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 08/17/2020] [Indexed: 11/10/2022] Open
Abstract
Background The regulation of exocytosis is physiologically vital in cells and requires a variety of distinct proteins and lipids that facilitate efficient, fast, and timely release of secretory vesicle cargo. Growing evidence suggests that regulatory lipids act as important lipid signals and regulate various biological processes including exocytosis. Though functional roles of many of these regulatory lipids has been linked to exocytosis, the dynamic behavior of these lipids during membrane fusion at sites of exocytosis in cell culture remains unknown. Methods Total internal reflection fluorescence microscopy (TIRF) was used to observe the spatial organization and temporal dynamics (i.e. spatial positioning and timing patterns) of several lipids, and accessory proteins, like lipid kinases and protein kinases, in the form of protein kinase C (PRKC) associated with sites of exocytosis of matrix metalloproteinase-9 (MMP-9) in living MCF-7 cancer cells. Results Following stimulation with phorbol myristate acetate (PMA) to promote exocytosis, a transient accumulation of several distinct regulatory lipids, lipid kinases, and protein kinases at exocytic sites was observed. This transient accumulation centered at the time of membrane fusion is followed by a rapid diffusion away from the fusion sites. Additionally, the synthesis of these regulatory lipids, degradation of these lipids, and the downstream effectors activated by these lipids, are also achieved by the recruitment and accumulation of key enzymes at exocytic sites (during the moment of cargo release). This includes key enzymes like lipid kinases, protein kinases, and phospholipases that facilitate membrane fusion and exocytosis of MMP-9. Conclusions This work suggests that these regulatory lipids and associated effector proteins are locally synthesized and/or recruited to sites of exocytosis, during membrane fusion and cargo release. More importantly, their enrichment at fusion sites serves as an important spatial and temporal organizing “element” defining individual exocytic sites.
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Affiliation(s)
- Dominique C Stephens
- Department of Chemistry, Howard University, 525 College Street NW, Washington, D.C, 20059, USA
| | - Tyrel W Powell
- Department of Chemistry, Howard University, 525 College Street NW, Washington, D.C, 20059, USA
| | - Justin W Taraska
- Laboratory of Molecular Biophysics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Dinari A Harris
- Department of Chemistry, Howard University, 525 College Street NW, Washington, D.C, 20059, USA.
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Dugail I, Amri EZ, Vitale N. High prevalence for obesity in severe COVID-19: Possible links and perspectives towards patient stratification. Biochimie 2020; 179:257-265. [PMID: 32649962 PMCID: PMC7340594 DOI: 10.1016/j.biochi.2020.07.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 07/02/2020] [Accepted: 07/02/2020] [Indexed: 12/18/2022]
Abstract
It is becoming obvious that in addition to aging and various hearth pathologies, excess of body weight, especially obesity is a major risk factor for severity of COVID-19 infection. Intriguingly the receptor for SARS-CoV-2 is ACE2, a member of the angiotensin receptor family that has a relatively large tissue distribution. This observation likely explains the multitude of symptoms that have been described from human patients. The adipose tissue also expresses ACE2, suggesting that adipocytes are potentially infected by SARS-CoV-2. Here we discuss some of the potential contribution of the adipose tissue to the severity of the infection and propose some aspects of obese patients metabolic phenotyping to help stratification of individuals with high risk of severe disease.
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Affiliation(s)
- Isabelle Dugail
- UMRS 1269 INSERM/Sorbonne University, Nutriomics, Faculté de médecine Pitié-Salpêtrière, F-75013, Paris, France; Member of the scientific council of the Groupe d'Etude et de Recherche en Lipidomique (GERLI), France
| | - Ez-Zoubir Amri
- Université Côte d'Azur, CNRS, Inserm, iBV, Nice, France; Member of the scientific council of the Groupe d'Etude et de Recherche en Lipidomique (GERLI), France
| | - Nicolas Vitale
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000, Strasbourg, France; Member of the scientific council of the Groupe d'Etude et de Recherche en Lipidomique (GERLI), France.
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31
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Mori A, Imai Y, Hattori N. Lipids: Key Players That Modulate α-Synuclein Toxicity and Neurodegeneration in Parkinson's Disease. Int J Mol Sci 2020; 21:ijms21093301. [PMID: 32392751 PMCID: PMC7247581 DOI: 10.3390/ijms21093301] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 05/04/2020] [Accepted: 05/05/2020] [Indexed: 12/20/2022] Open
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease; it is characterized by the loss of dopaminergic neurons in the midbrain and the accumulation of neuronal inclusions, mainly consisting of α-synuclein (α-syn) fibrils in the affected regions. The prion-like property of the pathological forms of α-syn transmitted via neuronal circuits has been considered inherent in the nature of PD. Thus, one of the potential targets in terms of PD prevention is the suppression of α-syn conversion from the functional form to pathological forms. Recent studies suggested that α-syn interacts with synaptic vesicle membranes and modulate the synaptic functions. A series of studies suggest that transient interaction of α-syn as multimers with synaptic vesicle membranes composed of phospholipids and other lipids is required for its physiological function, while an α-syn-lipid interaction imbalance is believed to cause α-syn aggregation and the resultant pathological α-syn conversion. Altered lipid metabolisms have also been implicated in the modulation of PD pathogenesis. This review focuses on the current literature reporting the role of lipids, especially phospholipids, and lipid metabolism in α-syn dynamics and aggregation processes.
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Affiliation(s)
- Akio Mori
- Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan;
| | - Yuzuru Imai
- Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan;
- Department of Research for Parkinson’s Disease, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
- Correspondence: (Y.I.); (N.H.); Tel.: +81-3-6801-8332 (Y.I. & N.H.)
| | - Nobutaka Hattori
- Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan;
- Department of Research for Parkinson’s Disease, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
- Correspondence: (Y.I.); (N.H.); Tel.: +81-3-6801-8332 (Y.I. & N.H.)
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32
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Philipsen MH, Phan NTN, Fletcher JS, Ewing AG. Interplay between Cocaine, Drug Removal, and Methylphenidate Reversal on Phospholipid Alterations in Drosophila Brain Determined by Imaging Mass Spectrometry. ACS Chem Neurosci 2020; 11:806-813. [PMID: 32045198 PMCID: PMC7077924 DOI: 10.1021/acschemneuro.0c00014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Cocaine dependence displays a broad impairment in cognitive performance including attention, learning, and memory. To obtain a better understanding of the action of cocaine in the nervous system, and the relation between phospholipids and memory, we have investigated whether phospholipids recover in the brain following cocaine removal using the fly model, Drosophila melanogaster. In addition, the effects of methylphenidate, a substitute medication for cocaine dependence, on fly brain lipids after cocaine abuse are also determined to see if it can rescue the lipid changes caused by cocaine. Time of flight secondary ion mass spectrometry with a (CO2)6000+ gas cluster ion beam was used to detect intact phospholipids. We show that cocaine has persistent effects, both increasing and decreasing the levels of specific phosphatidylethanolamines and phosphatidylinositols. These changes remain after cocaine withdrawal and are not rescued by methylphenidate. Cocaine is again shown to generally increase the levels of phosphatidylcholines in the fly brain; however, after drug withdrawal, the abundance of these lipids returns to the original level and methylphenidate treatment of the flies following cocaine exposure enhances the reversal of the lipid level reducing them below the original control. The study provides insight into the molecular effects of cocaine and methylphenidate on brain lipids. We suggest that phosphatidylcholines could be a potential target for the treatment of cocaine abuse as well as be a significant hallmark of cognition and memory loss with cocaine.
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Affiliation(s)
- Mai Hoang Philipsen
- The Gothenburg Imaging Mass Spectrometry (Go:IMS) Platform, Gothenburg, Sweden
| | - Nhu T. N. Phan
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg 412 96, Sweden
- The Gothenburg Imaging Mass Spectrometry (Go:IMS) Platform, Gothenburg, Sweden
| | - John Stephen Fletcher
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg 412 96, Sweden
- The Gothenburg Imaging Mass Spectrometry (Go:IMS) Platform, Gothenburg, Sweden
| | - Andrew G. Ewing
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg 412 96, Sweden
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg 412 96, Sweden
- The Gothenburg Imaging Mass Spectrometry (Go:IMS) Platform, Gothenburg, Sweden
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33
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Joensuu M, Wallis TP, Saber SH, Meunier FA. Phospholipases in neuronal function: A role in learning and memory? J Neurochem 2020; 153:300-333. [PMID: 31745996 DOI: 10.1111/jnc.14918] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 10/29/2019] [Accepted: 11/15/2019] [Indexed: 12/20/2022]
Abstract
Despite the human brain being made of nearly 60% fat, the vast majority of studies on the mechanisms of neuronal communication which underpin cognition, memory and learning, primarily focus on proteins and/or (epi)genetic mechanisms. Phospholipids are the main component of all cellular membranes and function as substrates for numerous phospholipid-modifying enzymes, including phospholipases, which release free fatty acids (FFAs) and other lipid metabolites that can alter the intrinsic properties of the membranes, recruit and activate critical proteins, and act as lipid signalling molecules. Here, we will review brain specific phospholipases, their roles in membrane remodelling, neuronal function, learning and memory, as well as their disease implications. In particular, we will highlight key roles of unsaturated FFAs, particularly arachidonic acid, in neurotransmitter release, neuroinflammation and memory. In light of recent findings, we will also discuss the emerging role of phospholipase A1 and the creation of saturated FFAs in the brain.
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Affiliation(s)
- Merja Joensuu
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Qld, Australia.,Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | - Tristan P Wallis
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Qld, Australia
| | - Saber H Saber
- Laboratory of Molecular Cell Biology, Department of Zoology, Faculty of Science, Assiut University, Assiut, Egypt
| | - Frédéric A Meunier
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Qld, Australia
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34
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Baneux C, Tanguy E, Thahouly T, Vitale A, Chasserot-Golaz S, Bader MF, Gasman S, Vitale N. Phosphatidic acid metabolism regulates neuroendocrine secretion but is not under the direct control of lipins. IUBMB Life 2020; 72:533-543. [PMID: 31967386 DOI: 10.1002/iub.2229] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 01/04/2020] [Indexed: 11/11/2022]
Abstract
Phosphatidic acid (PA) produced by phospholipase D1 has been shown to contribute to secretory vesicle exocytosis in a large number of cell models. Among various hypotheses, PA may contribute to recruit and/or activate at the exocytotic site a set of proteins from the molecular machinery dedicated to secretion, but also directly influence membrane curvature thereby favoring membrane rearrangements required for membrane fusion. The release of informative molecules by regulated exocytosis is a tightly controlled process. It is thus expected that PA produced to trigger membrane fusion should be rapidly metabolized and converted in a lipid that does not present similar characteristics. PA-phosphatases of the lipin family are possible candidates as they convert PA into diacylglycerol. We show here that lipin 1 and lipin 2 are expressed in neuroendocrine cells where they are cytosolic, but also partially associated with the endoplasmic reticulum. Silencing of lipin 1 or 2 did not affect significantly either basal or evoked secretion from PC12 cells, suggesting that it is unlikely that conversion of PA into a secondary lipid by lipins might represent a regulatory step in exocytosis in neurosecretory cells. However, in agreement with a model in which PA-metabolism could contribute to prevent entering into exocytosis of additional secretory vesicles, ectopic expression of lipin1B-GFP in bovine chromaffin cells reduced the number of exocytotic events as revealed by carbon fiber amperometry recording. Furthermore, individual spike parameters reflecting fusion pore dynamics were also modified by lipin1B-GFP, suggesting that a tight control of PA levels represents an important regulatory step of the number and kinetic of exocytotic events.
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Affiliation(s)
- Claire Baneux
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Emeline Tanguy
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Tamou Thahouly
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Alessio Vitale
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Sylvette Chasserot-Golaz
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Marie-France Bader
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Stéphane Gasman
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Nicolas Vitale
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
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Wang H, Zhang C, Xiao H. Mechanism of membrane fusion: protein-protein interaction and beyond. INTERNATIONAL JOURNAL OF PHYSIOLOGY, PATHOPHYSIOLOGY AND PHARMACOLOGY 2019; 11:250-257. [PMID: 31993099 PMCID: PMC6971501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 11/20/2019] [Indexed: 06/10/2023]
Abstract
Membrane fusion is a universal event in all living organism. It is at the heart of intracellular organelle biogenesis and membrane traffic processes such as endocytosis and exocytosis, and is also used by enveloped viruses to enter hosting cells. Regarding the cellular mechanisms underlying membrane fusion, pioneering studies by Randy Schekman, James Rothman, Thomas C. Südhof and their colleagues have demonstrated the function of specific proteins and protein-protein interactions as essential fusogenic factor to initiate membrane fusion. Since then, function of lipids and protein-lipid interaction has also been identified as important players in membrane fusion. Based on that NSF (NEM-sensitive factor where NEM stands for N-ethyl-maleimide) and acyl-CoA are required for the membrane fusion of transporting vesicles with Golgi cisternae, it is further suggested that the transfer of the acyl chain to a molecule(s) is essential for membrane fusion. Among the previously identified fusogens, phosphatidic acid (PA) is found as an acyl chain recipient. Functionally, acylation of PA is required for tethering the membranes of Rab5a vesicles and early endosomes together during membrane fusion. As certain threshold of proximity between the donor and acceptor membrane is required to initiate membrane fusion, fusogenic factors beyond protein-protein and protein-lipid interaction need to be identified.
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Affiliation(s)
- Hongbing Wang
- Department of Physiology, Michigan State UniversityEast Lansing, Michigan 48824, USA
- Neuroscience Program, Michigan State UniversityEast Lansing, Michigan 48824, USA
| | - Chengliang Zhang
- Department of Physiology, Michigan State UniversityEast Lansing, Michigan 48824, USA
| | - Hua Xiao
- Department of Physiology, Michigan State UniversityEast Lansing, Michigan 48824, USA
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36
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McDermott MI, Wang Y, Wakelam MJO, Bankaitis VA. Mammalian phospholipase D: Function, and therapeutics. Prog Lipid Res 2019; 78:101018. [PMID: 31830503 DOI: 10.1016/j.plipres.2019.101018] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 10/08/2019] [Accepted: 10/14/2019] [Indexed: 01/23/2023]
Abstract
Despite being discovered over 60 years ago, the precise role of phospholipase D (PLD) is still being elucidated. PLD enzymes catalyze the hydrolysis of the phosphodiester bond of glycerophospholipids producing phosphatidic acid and the free headgroup. PLD family members are found in organisms ranging from viruses, and bacteria to plants, and mammals. They display a range of substrate specificities, are regulated by a diverse range of molecules, and have been implicated in a broad range of cellular processes including receptor signaling, cytoskeletal regulation and membrane trafficking. Recent technological advances including: the development of PLD knockout mice, isoform-specific antibodies, and specific inhibitors are finally permitting a thorough analysis of the in vivo role of mammalian PLDs. These studies are facilitating increased recognition of PLD's role in disease states including cancers and Alzheimer's disease, offering potential as a target for therapeutic intervention.
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Affiliation(s)
- M I McDermott
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114, United States of America.
| | - Y Wang
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114, United States of America; Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843-2128, United States of America
| | - M J O Wakelam
- Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, United Kingdom
| | - V A Bankaitis
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114, United States of America; Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843-2128, United States of America; Department of Chemistry, Texas A&M University, College Station, Texas 77840, United States of America
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37
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Zhukovsky MA, Filograna A, Luini A, Corda D, Valente C. Phosphatidic acid in membrane rearrangements. FEBS Lett 2019; 593:2428-2451. [PMID: 31365767 DOI: 10.1002/1873-3468.13563] [Citation(s) in RCA: 99] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 07/25/2019] [Accepted: 07/26/2019] [Indexed: 12/16/2022]
Abstract
Phosphatidic acid (PA) is the simplest cellular glycerophospholipid characterized by unique biophysical properties: a small headgroup; negative charge; and a phosphomonoester group. Upon interaction with lysine or arginine, PA charge increases from -1 to -2 and this change stabilizes protein-lipid interactions. The biochemical properties of PA also allow interactions with lipids in several subcellular compartments. Based on this feature, PA is involved in the regulation and amplification of many cellular signalling pathways and functions, as well as in membrane rearrangements. Thereby, PA can influence membrane fusion and fission through four main mechanisms: it is a substrate for enzymes producing lipids (lysophosphatidic acid and diacylglycerol) that are involved in fission or fusion; it contributes to membrane rearrangements by generating negative membrane curvature; it interacts with proteins required for membrane fusion and fission; and it activates enzymes whose products are involved in membrane rearrangements. Here, we discuss the biophysical properties of PA in the context of the above four roles of PA in membrane fusion and fission.
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Affiliation(s)
- Mikhail A Zhukovsky
- Institute of Protein Biochemistry and Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Angela Filograna
- Institute of Protein Biochemistry and Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Alberto Luini
- Institute of Protein Biochemistry and Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Daniela Corda
- Institute of Protein Biochemistry and Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Carmen Valente
- Institute of Protein Biochemistry and Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
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38
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Gabel M, Delavoie F, Royer C, Tahouly T, Gasman S, Bader MF, Vitale N, Chasserot-Golaz S. Phosphorylation cycling of Annexin A2 Tyr23 is critical for calcium-regulated exocytosis in neuroendocrine cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2019; 1866:1207-1217. [DOI: 10.1016/j.bbamcr.2018.12.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 12/21/2018] [Accepted: 12/22/2018] [Indexed: 10/27/2022]
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39
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Barber CN, Raben DM. Lipid Metabolism Crosstalk in the Brain: Glia and Neurons. Front Cell Neurosci 2019; 13:212. [PMID: 31164804 PMCID: PMC6536584 DOI: 10.3389/fncel.2019.00212] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 04/26/2019] [Indexed: 11/13/2022] Open
Abstract
Until recently, glial cells have been considered mainly support cells for neurons in the mammalian brain. However, many studies have unveiled a variety of glial functions including electrolyte homeostasis, inflammation, synapse formation, metabolism, and the regulation of neurotransmission. The importance of these functions illuminates significant crosstalk between glial and neuronal cells. Importantly, it is known that astrocytes secrete signals that can modulate both presynaptic and postsynaptic function. It is also known that the lipid compositions of the pre- and post-synaptic membranes of neurons greatly impact functions such as vesicle fusion and receptor mobility. These data suggest an essential lipid-mediated communication between glial cells and neurons. Little is known, however, about how the lipid metabolism of both cell types may interact. In this review, we discuss neuronal and glial lipid metabolism and suggest how they might interact to impact neurotransmission.
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Affiliation(s)
- Casey N Barber
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Daniel M Raben
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
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40
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Jiang ZJ, Delaney TL, Zanin MP, Haberberger RV, Pitson SM, Huang J, Alford S, Cologna SM, Keating DJ, Gong LW. Extracellular and intracellular sphingosine-1-phosphate distinctly regulates exocytosis in chromaffin cells. J Neurochem 2019; 149:729-746. [PMID: 30963576 DOI: 10.1111/jnc.14703] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 12/28/2018] [Accepted: 03/27/2019] [Indexed: 01/18/2023]
Abstract
Sphingosine-1-phosphate (S1P) is an essential bioactive sphingosine lipid involved in many neurological disorders. Sphingosine kinase 1 (SphK1), a key enzyme for S1P production, is concentrated in presynaptic terminals. However, the role of S1P/SphK1 signaling in exocytosis remains elusive. By detecting catecholamine release from single vesicles in chromaffin cells, we show that a dominant negative SphK1 (SphK1DN ) reduces the number of amperometric spikes and increases the duration of foot, which reflects release through a fusion pore, implying critical roles for S1P in regulating the rate of exocytosis and fusion pore expansion. Similar phenotypes were observed in chromaffin cells obtained from SphK1 knockout mice compared to those from wild-type mice. In addition, extracellular S1P treatment increased the number of amperometric spikes, and this increase, in turn, was inhibited by a selective S1P3 receptor blocker, suggesting extracellular S1P may regulate the rate of exocytosis via activation of S1P3. Furthermore, intracellular S1P application induced a decrease in foot duration of amperometric spikes in control cells, indicating intracellular S1P may regulate fusion pore expansion during exocytosis. Taken together, our study represents the first demonstration that S1P regulates exocytosis through distinct mechanisms: extracellular S1P may modulate the rate of exocytosis via activation of S1P receptors while intracellular S1P may directly control fusion pore expansion during exocytosis. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.
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Affiliation(s)
- Zhong-Jiao Jiang
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Taylor L Delaney
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Mark P Zanin
- State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou, Guangdong, P.R. China
| | - Rainer V Haberberger
- College of Medicine and Public Health and Centre for Neuroscience, Flinders University, Adelaide, Australia
| | - Stuart M Pitson
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia, Australia
| | - Jian Huang
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Simon Alford
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Stephanie M Cologna
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Damien J Keating
- College of Medicine and Public Health and Centre for Neuroscience, Flinders University, Adelaide, Australia
| | - Liang-Wei Gong
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
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41
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Benedetto R, Ousingsawat J, Cabrita I, Pinto M, Lérias JR, Wanitchakool P, Schreiber R, Kunzelmann K. Plasma membrane-localized TMEM16 proteins are indispensable for expression of CFTR. J Mol Med (Berl) 2019; 97:711-722. [PMID: 30915480 DOI: 10.1007/s00109-019-01770-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 02/22/2019] [Accepted: 03/05/2019] [Indexed: 10/27/2022]
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) is the secretory chloride channel in epithelial tissues that has a central role in cystic fibrosis (CF) lung and gastrointestinal disease. A recent publication demonstrates a close association between CFTR and TMEM16A, the calcium-activated chloride channel. Thus, no CFTR chloride currents could be detected in airways and large intestine from mice lacking epithelial expression of TMEM16A. Here, we demonstrate that another plasma membrane-localized TMEM16 paralogue, TMEM16F, can compensate for the lack of TMEM16A. Using TMEM16 knockout mice, human lymphocytes, and a number of human cell lines with endogenous protein expression or heterologous expression, we demonstrate that CFTR can only function in the presence of either TMEM16A or TMEM16F. Double knockout of intestinal epithelial TMEM16A/F expression did not produce offsprings, suggesting a lethal phenotype in utero. Plasma membrane-localized TMEM16A or TMEM16F is required for exocytosis and expression of CFTR in the plasma membrane. TMEM16A/F proteins may therefore have an impact on disease severity in CF. KEY MESSAGES: • Cystic fibrosis is caused by the defective Cl- channel cystic fibrosis transmembrane conductance regulator (CFTR). • A close relationship exists between CFTR and the calcium-activated chloride channels TMEM16A/TMEM16F. • In conditional airway and intestinal knockout mice, lymphocytes from Scott disease patients and in overexpressing cells, CFTR is not functional in the absence of TMEM16A and TMEM16F. • TMEM16A and TMEM16F support membrane exocytosis and are essential for plasma membrane insertion of CFTR.
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Affiliation(s)
- Roberta Benedetto
- Physiological Institute, University of Regensburg, University Street 31, D-93053, Regensburg, Germany
| | - Jiraporn Ousingsawat
- Physiological Institute, University of Regensburg, University Street 31, D-93053, Regensburg, Germany
| | - Inês Cabrita
- Physiological Institute, University of Regensburg, University Street 31, D-93053, Regensburg, Germany
| | - Madalena Pinto
- Physiological Institute, University of Regensburg, University Street 31, D-93053, Regensburg, Germany
| | - Joana R Lérias
- Physiological Institute, University of Regensburg, University Street 31, D-93053, Regensburg, Germany
| | - Podchanart Wanitchakool
- Physiological Institute, University of Regensburg, University Street 31, D-93053, Regensburg, Germany
| | - Rainer Schreiber
- Physiological Institute, University of Regensburg, University Street 31, D-93053, Regensburg, Germany
| | - Karl Kunzelmann
- Physiological Institute, University of Regensburg, University Street 31, D-93053, Regensburg, Germany.
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42
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Bolomini-Vittori M, Mennens SFB, Joosten B, Fransen J, Du G, van den Dries K, Cambi A. PLD-dependent phosphatidic acid microdomains are signaling platforms for podosome formation. Sci Rep 2019; 9:3556. [PMID: 30837487 PMCID: PMC6401089 DOI: 10.1038/s41598-019-39358-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 01/22/2019] [Indexed: 01/07/2023] Open
Abstract
Local membrane phospholipid enrichment serves as docking platform for signaling proteins involved in many processes including cell adhesion and migration. Tissue-resident dendritic cells (DCs) assemble actomyosin-based structures called podosomes, which mediate adhesion and degradation of extracellular matrix for migration and antigen sampling. Recent evidence suggested the involvement of phospholipase D (PLD) and its product phosphatidic acid (PA) in podosome formation, but the spatiotemporal control of this process is poorly characterized. Here we determined the role of PLD1 and PLD2 isoforms in regulating podosome formation and dynamics in human primary DCs by combining PLD pharmacological inhibition with a fluorescent PA sensor and fluorescence microscopy. We found that ongoing PLD2 activity is required for the maintenance of podosomes, whereas both PLD1 and PLD2 control the early stages of podosome assembly. Furthermore, we captured the formation of PA microdomains accumulating at the membrane cytoplasmic leaflet of living DCs, in dynamic coordination with nascent podosome actin cores. Finally, we show that both PLD1 and PLD2 activity are important for podosome-mediated matrix degradation. Our results provide novel insight into the isoform-specific spatiotemporal regulation of PLD activity and further our understanding of the role of cell membrane phospholipids in controlling localized actin polymerization and cell protrusion.
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Affiliation(s)
- Matteo Bolomini-Vittori
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Svenja F B Mennens
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Ben Joosten
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Microscopic Imaging Center, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Jack Fransen
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Microscopic Imaging Center, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Guangwei Du
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center, Houston, Texas, USA
| | - Koen van den Dries
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Alessandra Cambi
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.
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43
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A Flower-Specific Phospholipase D Is a Stigmatic Compatibility Factor Targeted by the Self-Incompatibility Response in Brassica napus. Curr Biol 2019; 29:506-512.e4. [DOI: 10.1016/j.cub.2018.12.037] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 10/24/2018] [Accepted: 12/19/2018] [Indexed: 11/24/2022]
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44
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Tanguy E, Wang Q, Moine H, Vitale N. Phosphatidic Acid: From Pleiotropic Functions to Neuronal Pathology. Front Cell Neurosci 2019; 13:2. [PMID: 30728767 PMCID: PMC6351798 DOI: 10.3389/fncel.2019.00002] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 01/07/2019] [Indexed: 11/17/2022] Open
Abstract
Among the cellular lipids, phosphatidic acid (PA) is a peculiar one as it is at the same time a key building block of phospholipid synthesis and a major lipid second messenger conveying signaling information. The latter is thought to largely occur through the ability of PA to recruit and/or activate specific proteins in restricted compartments and within those only at defined submembrane areas. Furthermore, with its cone-shaped geometry PA locally changes membrane topology and may thus be a key player in membrane trafficking events, especially in membrane fusion and fission steps, where lipid remodeling is believed to be crucial. These pleiotropic cellular functions of PA, including phospholipid synthesis and homeostasis together with important signaling activity, imply that perturbations of PA metabolism could lead to serious pathological conditions. In this mini-review article, after outlining the main cellular functions of PA, we highlight the different neurological diseases that could, at least in part, be attributed to an alteration in PA synthesis and/or catabolism.
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Affiliation(s)
- Emeline Tanguy
- Institut des Neurosciences Cellulaires et Intégratives (INCI), UPR-3212 Centre National de la Recherche Scientifique & Université de Strasbourg, Strasbourg, France
| | - Qili Wang
- Institut des Neurosciences Cellulaires et Intégratives (INCI), UPR-3212 Centre National de la Recherche Scientifique & Université de Strasbourg, Strasbourg, France
| | - Hervé Moine
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), CNRS UMR 7104, INSERM U964, Université de Strasbourg, Illkirch-Graffenstaden, France
| | - Nicolas Vitale
- Institut des Neurosciences Cellulaires et Intégratives (INCI), UPR-3212 Centre National de la Recherche Scientifique & Université de Strasbourg, Strasbourg, France
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45
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Skafi N, Abdallah D, Soulage C, Reibel S, Vitale N, Hamade E, Faour W, Magne D, Badran B, Hussein N, Buchet R, Brizuela L, Mebarek S. Phospholipase D: A new mediator during high phosphate-induced vascular calcification associated with chronic kidney disease. J Cell Physiol 2018; 234:4825-4839. [PMID: 30207376 DOI: 10.1002/jcp.27281] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 07/26/2018] [Indexed: 01/31/2023]
Abstract
Vascular calcification (VC) is the pathological accumulation of calcium phosphate crystals in one of the layers of blood vessels, leading to loss of elasticity and causing severe calcification in vessels. Medial calcification is mostly seen in patients with chronic kidney disease (CKD) and diabetes. Identification of key enzymes and their actions during calcification will contribute to understand the onset of pathological calcification. Phospholipase D (PLD1, PLD2) is active at the earlier steps of mineralization in osteoblasts and chondrocytes. In this study, we aimed to determine their effects during high-phosphate treatment in mouse vascular smooth muscle cell line MOVAS, in the ex vivo model of the rat aorta, and in the in vivo model of adenine-induced CKD. We observed an early increase in PLD1 gene and protein expression along with the increase in the PLD activity in vascular muscle cell line, during calcification induced by ascorbic acid and β-glycerophosphate. Inhibition of PLD1 by the selective inhibitor VU0155069, or the pan-PLD inhibitor, halopemide, prevented calcification. The mechanism of PLD activation is likely to be protein kinase C (PKC)-independent since bisindolylmaleimide X hydrochloride, a pan-PKC inhibitor, did not affect the PLD activity. In agreement, we found an increase in Pld1 gene expression and PLD activity in aortic explant cultures treated with high phosphate, whereas PLD inhibition by halopemide decreased calcification. Finally, an increase in both Pld1 and Pld2 expression occurred simultaneously with the appearance of VC in a rat model of CKD. Thus, PLD, especially PLD1, promotes VC in the context of CKD and could be an important target for preventing onset or progression of VC.
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Affiliation(s)
- Najwa Skafi
- University of Lyon, Université Claude Bernard Lyon 1 (UCBL), CNRS UMR 5246, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires (ICBMS), Lyon, France.,Genomic and Health Laboratory/PRASE-EDST Campus Rafic Hariri-Hadath-Beirut-Liban, Faculty of Sciences, Lebanese University (LU), Beirut, Lebanon
| | - Dina Abdallah
- University of Lyon, Université Claude Bernard Lyon 1 (UCBL), CNRS UMR 5246, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires (ICBMS), Lyon, France.,Genomic and Health Laboratory/PRASE-EDST Campus Rafic Hariri-Hadath-Beirut-Liban, Faculty of Sciences, Lebanese University (LU), Beirut, Lebanon
| | - Christophe Soulage
- University of Lyon, CarMeN, INSERM U1060, INRA U1397, Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université Claude Bernard Lyon 1, Villeurbanne, France
| | | | - Nicolas Vitale
- Institut des Neurosciences Cellulaires et Intégratives (INCI), UPR-3212 CNRS and Université de Strasbourg, Strasbourg, France
| | - Eva Hamade
- Genomic and Health Laboratory/PRASE-EDST Campus Rafic Hariri-Hadath-Beirut-Liban, Faculty of Sciences, Lebanese University (LU), Beirut, Lebanon
| | - Wissam Faour
- School of Medicine, Lebanese American University (LAU), Byblos, Lebanon
| | - David Magne
- University of Lyon, Université Claude Bernard Lyon 1 (UCBL), CNRS UMR 5246, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires (ICBMS), Lyon, France
| | - Bassam Badran
- Genomic and Health Laboratory/PRASE-EDST Campus Rafic Hariri-Hadath-Beirut-Liban, Faculty of Sciences, Lebanese University (LU), Beirut, Lebanon
| | - Nader Hussein
- Genomic and Health Laboratory/PRASE-EDST Campus Rafic Hariri-Hadath-Beirut-Liban, Faculty of Sciences, Lebanese University (LU), Beirut, Lebanon
| | - Rene Buchet
- University of Lyon, Université Claude Bernard Lyon 1 (UCBL), CNRS UMR 5246, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires (ICBMS), Lyon, France
| | - Leyre Brizuela
- University of Lyon, Université Claude Bernard Lyon 1 (UCBL), CNRS UMR 5246, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires (ICBMS), Lyon, France
| | - Saida Mebarek
- University of Lyon, Université Claude Bernard Lyon 1 (UCBL), CNRS UMR 5246, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires (ICBMS), Lyon, France
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46
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Actin Remodeling in Regulated Exocytosis: Toward a Mesoscopic View. Trends Cell Biol 2018; 28:685-697. [DOI: 10.1016/j.tcb.2018.04.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 04/05/2018] [Accepted: 04/13/2018] [Indexed: 01/10/2023]
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47
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Scheidt HA, Kolocaj K, Veje Kristensen J, Huster D, Langosch D. Transmembrane Helix Induces Membrane Fusion through Lipid Binding and Splay. J Phys Chem Lett 2018; 9:3181-3186. [PMID: 29799756 DOI: 10.1021/acs.jpclett.8b00859] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The fusion of biological membranes may require splayed lipids whose tails transiently visit the headgroup region of the bilayer, a scenario suggested by molecular dynamics simulations. Here, we examined the lipid splay hypothesis experimentally by relating liposome fusion and lipid splay induced by model transmembrane domains (TMDs). Our results reveal that a conformationally flexible transmembrane helix promotes outer leaflet mixing and lipid splay more strongly than a conformationally rigid one. The lipid dependence of basal as well as of TMD-driven lipid mixing and splay suggests that the cone-shaped phosphatidylethanolamine stimulates basal fusion via enhancing lipid splay and that the negatively charged phosphatidylserine inhibits fusion via electrostatic repulsion. Phosphatidylserine also strongly differentiates basal and helix-driven fusion, which is related to its preferred interaction with the conformationally more flexible transmembrane helix. Thus, the contribution of a transmembrane helix to membrane fusion appears to depend on lipid binding, which results in lipid splay.
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Affiliation(s)
- Holger A Scheidt
- Institute for Medical Physics and Biophysics , Leipzig University , Härtelstrasse 16-18 , 04107 Leipzig , Germany
| | - Katja Kolocaj
- Lehrstuhl für Chemie der Biopolymere , Technische Universität München , Weihenstephaner Berg 3 , 85354 Freising , Germany
- Munich Center For Integrated Protein Science (CIPSM) , Butenandtstrasse 5 , 81377 München , Germany
| | - Julie Veje Kristensen
- Lehrstuhl für Chemie der Biopolymere , Technische Universität München , Weihenstephaner Berg 3 , 85354 Freising , Germany
- Munich Center For Integrated Protein Science (CIPSM) , Butenandtstrasse 5 , 81377 München , Germany
| | - Daniel Huster
- Institute for Medical Physics and Biophysics , Leipzig University , Härtelstrasse 16-18 , 04107 Leipzig , Germany
| | - Dieter Langosch
- Lehrstuhl für Chemie der Biopolymere , Technische Universität München , Weihenstephaner Berg 3 , 85354 Freising , Germany
- Munich Center For Integrated Protein Science (CIPSM) , Butenandtstrasse 5 , 81377 München , Germany
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48
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Protein⁻Phospholipid Interaction Motifs: A Focus on Phosphatidic Acid. Biomolecules 2018; 8:biom8020020. [PMID: 29690573 PMCID: PMC6022864 DOI: 10.3390/biom8020020] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/16/2018] [Accepted: 04/16/2018] [Indexed: 12/12/2022] Open
Abstract
Cellular membranes are composed of thousands of different lipids usually maintained within a narrow range of concentrations. In addition to their well-known structural and metabolic roles, signaling functions for many lipids have also emerged over the last two decades. The latter largely depend on the ability of particular classes of lipids to interact specifically with a great variety of proteins and to regulate their localization and activity. Among these lipids, phosphatidic acid (PA) plays a unique role in a large repertoire of cellular activities, most likely in relation to its unique biophysical properties. However, until recently, only incomplete information was available to model the interaction between PA and its protein partners. The development of new liposome-based assays as well as molecular dynamic simulation are now providing novel information. We will review the different factors that have shown to modulate the capacity of PA to interact with specific domains in target proteins.
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49
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O'Donnell VB, Rossjohn J, Wakelam MJ. Phospholipid signaling in innate immune cells. J Clin Invest 2018; 128:2670-2679. [PMID: 29683435 DOI: 10.1172/jci97944] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Phospholipids comprise a large body of lipids that define cells and organelles by forming membrane structures. Importantly, their complex metabolism represents a highly controlled cellular signaling network that is essential for mounting an effective innate immune response. Phospholipids in innate cells are subject to dynamic regulation by enzymes, whose activities are highly responsive to activation status. Along with their metabolic products, they regulate multiple aspects of innate immune cell biology, including shape change, aggregation, blood clotting, and degranulation. Phospholipid hydrolysis provides substrates for cell-cell communication, enables regulation of hemostasis, immunity, thrombosis, and vascular inflammation, and is centrally important in cardiovascular disease and associated comorbidities. Phospholipids themselves are also recognized by innate-like T cells, which are considered essential for recognition of infection or cancer, as well as self-antigens. This Review describes the major phospholipid metabolic pathways present in innate immune cells and summarizes the formation and metabolism of phospholipids as well as their emerging roles in cell biology and disease.
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Affiliation(s)
- Valerie B O'Donnell
- Systems Immunity Research Institute and Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Jamie Rossjohn
- Systems Immunity Research Institute and Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom.,Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, and.,ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria, Australia
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50
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Sharma S, Lindau M. t-SNARE Transmembrane Domain Clustering Modulates Lipid Organization and Membrane Curvature. J Am Chem Soc 2017; 139:18440-18443. [PMID: 29231734 PMCID: PMC5802331 DOI: 10.1021/jacs.7b10677] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The t-SNARE complex plays a central role in neuronal fusion. Its components, syntaxin-1 and SNAP25, are largely present in individual clusters and partially colocalize at the presumptive fusion site. How these protein clusters modify local lipid composition and membrane morphology is largely unknown. In this work, using coarse-grained molecular dynamics, the transmembrane domains (TMDs) of t-SNARE complexes are shown to form aggregates leading to formation of lipid nanodomains, which are enriched in cholesterol, phosphatidylinositol 4,5-bisphosphate, and gangliosidic lipids. These nano-domains induce membrane curvature that would promote a closer contact between vesicle and plasma membrane.
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Affiliation(s)
- Satyan Sharma
- Laboratory of Nanoscale Cell Biology, Max-Planck-Institut für Biophysikalische Chemie , Göttingen 37077 Germany
| | - Manfred Lindau
- Laboratory of Nanoscale Cell Biology, Max-Planck-Institut für Biophysikalische Chemie , Göttingen 37077 Germany.,School of Applied and Engineering Physics, Cornell University , Ithaca, New York 14850, United States
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