51
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Retinoid X Receptor α Regulates DHA-Dependent Spinogenesis and Functional Synapse Formation In Vivo. Cell Rep 2021; 31:107649. [PMID: 32433958 DOI: 10.1016/j.celrep.2020.107649] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 02/01/2020] [Accepted: 04/22/2020] [Indexed: 12/23/2022] Open
Abstract
Coordinated intracellular and extracellular signaling is critical to synapse development and functional neural circuit wiring. Here, we report that unesterified docosahexaenoic acid (DHA) regulates functional synapse formation in vivo via retinoid X receptor α (Rxra) signaling. Using Rxra conditional knockout (cKO) mice and virus-mediated transient gene expression, we show that endogenous Rxra plays important roles in regulating spinogenesis and excitatory synaptic transmission in cortical pyramidal neurons. We further show that the effects of RXRA are mediated through its DNA-binding domain in a cell-autonomous and reversible manner. Moreover, unesterified DHA increases spine formation and excitatory synaptic transmission in vivo in an Rxra-dependent fashion. Rxra cKO mice generally behave normally but show deficits in behavior tasks associated with social memory. Together, these results demonstrate that unesterified DHA signals through RXRA to regulate spinogenesis and functional synapse formation, providing insight into the mechanism through which DHA promotes brain development and cognitive function.
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52
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Isanta-Navarro J, Arnott SE, Klauschies T, Martin-Creuzburg D. Dietary lipid quality mediates salt tolerance of a freshwater keystone herbivore. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 769:144657. [PMID: 33493914 DOI: 10.1016/j.scitotenv.2020.144657] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/13/2020] [Accepted: 12/18/2020] [Indexed: 06/12/2023]
Abstract
Salinization of freshwater ecosystems is a growing hazard for organisms and ecosystem functioning worldwide. In northern latitudes, road salt that is being transported into water bodies can cause year-round increases in lake salinity levels. Exploring the environmental factors driving the susceptibility of freshwater zooplankton to road salt is crucial for assessing the impact of salinization on food web processes. We studied the role of essential lipids, i.e., sterols and long-chain polyunsaturated fatty acids (PUFAs), in mediating salt tolerance of the freshwater keystone herbivore Daphnia. Sterols and PUFAs are involved in regulating ion permeability of biological membranes and thus we hypothesized that the susceptibility to salt is affected by the dietary sterol and PUFA supply. Life history experiments revealed opposing effects of sterol and PUFA supplementation on salt tolerance, i.e., tolerance increased upon sterol supplementation but decreased upon PUFA supplementation, which is consistent with their proposed impact on membrane permeability. Our results suggest that the susceptibility of freshwater zooplankton to salinization strongly depends on the dietary lipid supply and thus the phytoplankton community composition. Hence, trophic state related differences in the phytoplankton community composition need to be considered when assessing the consequences of salinization for freshwater ecosystem functioning.
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Affiliation(s)
- Jana Isanta-Navarro
- Limnological Institute, University of Konstanz, Mainaustrasse 252, 78464 Konstanz, Germany.
| | - Shelley E Arnott
- Department of Biology, Queen's University, 116 Barrie Street, Kingston, ON K7L 3J9, Canada.
| | - Toni Klauschies
- Institute for Biochemistry and Biology, University of Potsdam, Maulbeerallee 2, 14469 Potsdam, Germany.
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53
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Kadri L, Bacle A, Khoury S, Vandebrouck C, Bescond J, Faivre JF, Ferreira T, Sebille S. Polyunsaturated Phospholipids Increase Cell Resilience to Mechanical Constraints. Cells 2021; 10:937. [PMID: 33920685 PMCID: PMC8073313 DOI: 10.3390/cells10040937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 04/10/2021] [Accepted: 04/13/2021] [Indexed: 11/24/2022] Open
Abstract
If polyunsaturated fatty acids (PUFAs) are generally accepted to be good for health, the mechanisms of their bona fide benefits still remain elusive. Membrane phospholipids (PLs) of the cardiovascular system and skeletal muscles are particularly enriched in PUFAs. The fatty acid composition of PLs is known to regulate crucial membrane properties, including elasticity and plasticity. Since muscle cells undergo repeated cycles of elongation and relaxation, we postulated in the present study that PUFA-containing PLs could be central players for muscle cell adaptation to mechanical constraints. By a combination of in cellulo and in silico approaches, we show that PUFAs, and particularly the ω-3 docosahexaenoic acid (DHA), regulate important properties of the plasma membrane that improve muscle cell resilience to mechanical constraints. Thanks to their unique property to contortionate within the bilayer plane, they facilitate the formation of vacuole-like dilation (VLD), which, in turn, avoid cell breakage under mechanical constraints.
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54
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Renard HF, Boucrot E. Unconventional endocytic mechanisms. Curr Opin Cell Biol 2021; 71:120-129. [PMID: 33862329 DOI: 10.1016/j.ceb.2021.03.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 02/23/2021] [Accepted: 03/05/2021] [Indexed: 02/06/2023]
Abstract
Endocytosis mediates the uptake of extracellular proteins, micronutrients and transmembrane cell surface proteins. Importantly, many viruses, toxins and bacteria hijack endocytosis to infect cells. The canonical pathway is clathrin-mediated endocytosis (CME) and is active in all eukaryotic cells to support critical house-keeping functions. Unconventional mechanisms of endocytosis exit in parallel of CME, to internalize specific cargoes and support various cellular functions. These clathrin-independent endocytic (CIE) routes use three distinct mechanisms: acute signaling-induced membrane remodeling drives macropinocytosis, activity-dependent bulk endocytosis (ADBE), massive endocytosis (MEND) and EGFR non-clathrin endocytosis (EGFR-NCE). Cargo capture and local membrane deformation by cytosolic proteins is used by fast endophilin-mediated endocytosis (FEME), IL-2Rβ endocytosis and ultrafast endocytosis at synapses. Finally, the formation of endocytic pits by clustering of extracellular lipids or cargoes according to the Glycolipid-Lectin (GL-Lect) hypothesis mediates the uptake of SV40 virus, Shiga and cholera toxins, and galectin-clustered receptors by the CLIC/GEEC and the endophilin-A3-mediated CIE.
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Affiliation(s)
- Henri-François Renard
- Biochemistry and Cellular Biology Research Unit (URBC), Namur Research Institute for Life Science (NARILIS), University of Namur, Rue de Bruxelles 61, B-50000, Namur, Belgium.
| | - Emmanuel Boucrot
- Institute of Structural and Molecular Biology, University College London, Gower Street, London, WC1E 6BT, UK; Institute of Structural and Molecular Biology, Birkbeck College, Malet Street, London, WC1E 7HX, UK.
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55
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Martinat M, Rossitto M, Di Miceli M, Layé S. Perinatal Dietary Polyunsaturated Fatty Acids in Brain Development, Role in Neurodevelopmental Disorders. Nutrients 2021; 13:1185. [PMID: 33918517 PMCID: PMC8065891 DOI: 10.3390/nu13041185] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 03/30/2021] [Accepted: 03/30/2021] [Indexed: 12/26/2022] Open
Abstract
n-3 and n-6 polyunsaturated fatty acids (PUFAs) are essential fatty acids that are provided by dietary intake. Growing evidence suggests that n-3 and n-6 PUFAs are paramount for brain functions. They constitute crucial elements of cellular membranes, especially in the brain. They are the precursors of several metabolites with different effects on inflammation and neuron outgrowth. Overall, long-chain PUFAs accumulate in the offspring brain during the embryonic and post-natal periods. In this review, we discuss how they accumulate in the developing brain, considering the maternal dietary supply, the polymorphisms of genes involved in their metabolism, and the differences linked to gender. We also report the mechanisms linking their bioavailability in the developing brain, their transfer from the mother to the embryo through the placenta, and their role in brain development. In addition, data on the potential role of altered bioavailability of long-chain n-3 PUFAs in the etiologies of neurodevelopmental diseases, such as autism, attention deficit and hyperactivity disorder, and schizophrenia, are reviewed.
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56
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Carbone BE, Abouleish M, Watters KE, Vogel S, Ribic A, Schroeder OHU, Bader BM, Biederer T. Synaptic Connectivity and Cortical Maturation Are Promoted by the ω-3 Fatty Acid Docosahexaenoic Acid. Cereb Cortex 2021; 30:226-240. [PMID: 31034037 DOI: 10.1093/cercor/bhz083] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 02/20/2019] [Accepted: 03/27/2019] [Indexed: 12/14/2022] Open
Abstract
Brain development is likely impacted by micronutrients. This is supported by the effects of the ω-3 fatty acid docosahexaenoic acid (DHA) during early neuronal differentiation, when it increases neurite growth. Aiming to delineate DHA roles in postnatal stages, we selected the visual cortex due to its stereotypic maturation. Immunohistochemistry showed that young mice that received dietary DHA from birth exhibited more abundant presynaptic and postsynaptic specializations. DHA also increased density and size of synapses in a dose-dependent manner in cultured neurons. In addition, dendritic arbors of neurons treated with DHA were more complex. In agreement with improved connectivity, DHA enhanced physiological parameters of network maturation in vitro, including bursting strength and oscillatory behavior. Aiming to analyze functional maturation of the cortex, we performed in vivo electrophysiological recordings from awake mice to measure responses to patterned visual inputs. Dietary DHA robustly promoted the developmental increase in visual acuity, without altering light sensitivity. The visual acuity of DHA-supplemented animals continued to improve even after their cortex had matured and DHA abolished the acuity plateau. Our findings show that the ω-3 fatty acid DHA promotes synaptic connectivity and cortical processing. These results provide evidence that micronutrients can support the maturation of neuronal networks.
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Affiliation(s)
- Beatrice E Carbone
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
| | - Malik Abouleish
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
| | - Katherine E Watters
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
| | - Seth Vogel
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
| | - Adema Ribic
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
| | | | | | - Thomas Biederer
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
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57
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Pereyra AS, Harris KL, Soepriatna AH, Waterbury QA, Bharathi SS, Zhang Y, Fisher-Wellman KH, Goergen CJ, Goetzman ES, Ellis JM. Octanoate is differentially metabolized in liver and muscle and fails to rescue cardiomyopathy in CPT2 deficiency. J Lipid Res 2021; 62:100069. [PMID: 33757734 PMCID: PMC8082564 DOI: 10.1016/j.jlr.2021.100069] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/19/2021] [Accepted: 02/20/2021] [Indexed: 12/30/2022] Open
Abstract
Long-chain fatty acid oxidation is frequently impaired in primary and systemic metabolic diseases affecting the heart; thus, therapeutically increasing reliance on normally minor energetic substrates, such as ketones and medium-chain fatty acids, could benefit cardiac health. However, the molecular fundamentals of this therapy are not fully known. Here, we explored the ability of octanoate, an eight-carbon medium-chain fatty acid known as an unregulated mitochondrial energetic substrate, to ameliorate cardiac hypertrophy in long-chain fatty acid oxidation-deficient hearts because of carnitine palmitoyltransferase 2 deletion (Cpt2M-/-). CPT2 converts acylcarnitines to acyl-CoAs in the mitochondrial matrix for oxidative bioenergetic metabolism. In Cpt2M-/- mice, high octanoate-ketogenic diet failed to alleviate myocardial hypertrophy, dysfunction, and acylcarnitine accumulation suggesting that this alternative substrate is not sufficiently compensatory for energy provision. Aligning this outcome, we identified a major metabolic distinction between muscles and liver, wherein heart and skeletal muscle mitochondria were unable to oxidize free octanoate, but liver was able to oxidize free octanoate. Liver mitochondria, but not heart or muscle, highly expressed medium-chain acyl-CoA synthetases, potentially enabling octanoate activation for oxidation and circumventing acylcarnitine shuttling. Conversely, octanoylcarnitine was oxidized by liver, skeletal muscle, and heart, with rates in heart 4-fold greater than liver and, in muscles, was not dependent upon CPT2. Together, these data suggest that dietary octanoate cannot rescue CPT2-deficient cardiac disease. These data also suggest the existence of tissue-specific mechanisms for octanoate oxidative metabolism, with liver being independent of free carnitine availability, whereas cardiac and skeletal muscles depend on carnitine but not on CPT2.
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Affiliation(s)
- Andrea S Pereyra
- Brody School of Medicine at East Carolina University, Department of Physiology, and East Carolina Diabetes and Obesity Institute, Greenville, NC, USA
| | - Kate L Harris
- Department of Biochemistry, Purdue University, West Lafayette, IN, USA
| | - Arvin H Soepriatna
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Quin A Waterbury
- Department of Biochemistry, Purdue University, West Lafayette, IN, USA
| | - Sivakama S Bharathi
- Department of Pediatrics, Children's Hospital of Pittsburgh of the University of Pittsburgh Medical Center, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Yuxun Zhang
- Department of Pediatrics, Children's Hospital of Pittsburgh of the University of Pittsburgh Medical Center, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Kelsey H Fisher-Wellman
- Brody School of Medicine at East Carolina University, Department of Physiology, and East Carolina Diabetes and Obesity Institute, Greenville, NC, USA
| | - Craig J Goergen
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Eric S Goetzman
- Department of Pediatrics, Children's Hospital of Pittsburgh of the University of Pittsburgh Medical Center, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Jessica M Ellis
- Brody School of Medicine at East Carolina University, Department of Physiology, and East Carolina Diabetes and Obesity Institute, Greenville, NC, USA.
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58
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Pezeshkian W, Marrink SJ. Simulating realistic membrane shapes. Curr Opin Cell Biol 2021; 71:103-111. [PMID: 33721706 DOI: 10.1016/j.ceb.2021.02.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/08/2021] [Accepted: 02/11/2021] [Indexed: 12/12/2022]
Abstract
Biological membranes exhibit diversity in their shapes and complexity in chemical compositions that are linked to many cellular functions. These two central features of biomembranes have been the subject of numerous simulation studies, using a diverse range of computational techniques. Currently, the field is able to capture this complexity at increasing levels of realism and connect the microscopic view on protein-lipid interactions to cellular morphologies at the level of entire organelles. Here we highlight recent advances in this topic, identify current bottlenecks, and sketch possible ways ahead.
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Affiliation(s)
- Weria Pezeshkian
- Groningen Biomolecular Sciences and Biotechnology Institute and Zernike Institute for Advanced Materials, University of Groningen, Groningen, the Netherlands
| | - Siewert J Marrink
- Groningen Biomolecular Sciences and Biotechnology Institute and Zernike Institute for Advanced Materials, University of Groningen, Groningen, the Netherlands.
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59
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Siggel M, Bhaskara RM, Moesser MK, D̵ikić I, Hummer G. FAM134B-RHD Protein Clustering Drives Spontaneous Budding of Asymmetric Membranes. J Phys Chem Lett 2021; 12:1926-1931. [PMID: 33591770 PMCID: PMC8028312 DOI: 10.1021/acs.jpclett.1c00031] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 02/10/2021] [Indexed: 05/28/2023]
Abstract
Living cells constantly remodel the shape of their lipid membranes. In the endoplasmic reticulum (ER), the reticulon homology domain (RHD) of the reticulophagy regulator 1 (RETR1/FAM134B) forms dense autophagic puncta that are associated with membrane removal by ER-phagy. In molecular dynamics (MD) simulations, we find that FAM134B-RHD spontaneously forms clusters, driven in part by curvature-mediated attractions. At a critical size, as in a nucleation process, the FAM134B-RHD clusters induce the formation of membrane buds. The kinetics of budding depends sensitively on protein concentration and bilayer asymmetry. Our MD simulations shed light on the role of FAM134B-RHD in ER-phagy and show that membrane asymmetry can be used to modulate the kinetic barrier for membrane remodeling.
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Affiliation(s)
- Marc Siggel
- Department
of Theoretical Biophysics, Max Planck Institute
of Biophysics, Max-von-Laue Str. 3, 60438 Frankfurt am Main, Germany
| | - Ramachandra M. Bhaskara
- Department
of Theoretical Biophysics, Max Planck Institute
of Biophysics, Max-von-Laue Str. 3, 60438 Frankfurt am Main, Germany
- Institute
of Biochemistry II, Faculty of Medicine, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
- Buchmann
Institute of Molecular Life Sciences, Goethe
University Frankfurt, Max-von-Laue Straße 15, 60438 Frankfurt am Main, Germany
| | - Melanie K. Moesser
- Department
of Theoretical Biophysics, Max Planck Institute
of Biophysics, Max-von-Laue Str. 3, 60438 Frankfurt am Main, Germany
| | - Ivan D̵ikić
- Institute
of Biochemistry II, Faculty of Medicine, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
- Max
Planck Institute of Biophysics, 60438 Frankfurt am Main, Germany
- Buchmann
Institute of Molecular Life Sciences, Goethe
University Frankfurt, Max-von-Laue Straße 15, 60438 Frankfurt am Main, Germany
| | - Gerhard Hummer
- Department
of Theoretical Biophysics, Max Planck Institute
of Biophysics, Max-von-Laue Str. 3, 60438 Frankfurt am Main, Germany
- Institute
of Biophysics, Goethe University Frankfurt, 60438 Frankfurt
am Main, Germany
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60
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Lipowsky R, Dimova R. Introduction to remodeling of biomembranes. SOFT MATTER 2021; 17:214-221. [PMID: 33406179 DOI: 10.1039/d0sm90234a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In general, biomembranes and giant vesicles can respond to cues in their aqueous environment by remodeling their molecular composition, shape, or topology. This themed collection focuses on remodeling of membrane shape which is intimately related to membrane curvature. In this introductory contribution, we clarify the different notions of curvature and describe the general nanoscopic mechanisms for curvature generation and membrane scaffolding. At the end, we give a brief outlook on membrane tension.
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Affiliation(s)
- Reinhard Lipowsky
- Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, Germany.
| | - Rumiana Dimova
- Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, Germany.
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61
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Gao YG, My Le L, Alam A, Brown R. A Simple and Straightforward Approach for Generating Small, Stable, Homogeneous, Unilamellar 1-Palmitoyl 2-Oleoyl Phosphatidylcholine (POPC) Bilayer Vesicles. Bio Protoc 2021; 11:e4271. [DOI: 10.21769/bioprotoc.4271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/28/2021] [Accepted: 09/30/2021] [Indexed: 11/02/2022] Open
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62
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Urbanelli L, Buratta S, Logozzi M, Mitro N, Sagini K, Raimo RD, Caruso D, Fais S, Emiliani C. Lipidomic analysis of cancer cells cultivated at acidic pH reveals phospholipid fatty acids remodelling associated with transcriptional reprogramming. J Enzyme Inhib Med Chem 2020; 35:963-973. [PMID: 32308048 PMCID: PMC7191909 DOI: 10.1080/14756366.2020.1748025] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Cancer cells need to modulate the biosynthesis of membrane lipids and fatty acids to adapt themselves to an accelerated rate of cell division and survive into an extracellular environment characterised by a low pH. To gain insight this crucial survival process, we investigated the lipid composition of Mel 501 melanoma cells cultured at either physiological or acidic pH and observed the remodelling of phospholipids towards longer and more unsaturated acyl chains at low pH. This modification was related to changes in gene expression profile, as we observed an up-regulation of genes involved in acyl chain desaturation, elongation and transfer to phospholipids. PC3 prostate and MCF7 breast cancer cells adapted at acidic pH also demonstrated phospholipid fatty acid remodelling related to gene expression changes. Overall findings clearly indicate that low extracellular pH impresses a specific lipid signature to cells, associated with transcriptional reprogramming.
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Affiliation(s)
- Lorena Urbanelli
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, Italy
| | - Sandra Buratta
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, Italy
| | - Mariantonia Logozzi
- Department of Oncology and Molecular Medicine, National Institute of Health, Rome, Italy
| | - Nico Mitro
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Krizia Sagini
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, Italy
| | - Rossella Di Raimo
- Department of Oncology and Molecular Medicine, National Institute of Health, Rome, Italy
| | - Donatella Caruso
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Stefano Fais
- Department of Oncology and Molecular Medicine, National Institute of Health, Rome, Italy
| | - Carla Emiliani
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, Italy.,CEMIN-Center of Excellence for Innovative Nanostructured Material, University of Perugia, Perugia, Italy
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63
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de Santis A, Vitiello G, Appavou MS, Scoppola E, Fragneto G, Barnsley LC, Clifton LA, Ottaviani MF, Paduano L, Russo Krauss I, D'Errico G. Not just a fluidifying effect: omega-3 phospholipids induce formation of non-lamellar structures in biomembranes. SOFT MATTER 2020; 16:10425-10438. [PMID: 33165495 DOI: 10.1039/d0sm01549k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Polyunsaturated omega-3 fatty acid docosahexaenoic acid (DHA) is found in very high concentrations in a few peculiar tissues, suggesting that it must have a specialized role. DHA was proposed to affect the function of the cell membrane and related proteins through an indirect mechanism of action, based on the DHA-phospholipid effects on the lipid bilayer structure. In this respect, most studies have focused on its influence on lipid-rafts, somehow neglecting the analysis of effects on liquid disordered phases that constitute most of the cell membranes, by reporting in these cases only a general fluidifying effect. In this study, by combining neutron reflectivity, cryo-transmission electron microscopy, small angle neutron scattering, dynamic light scattering and electron paramagnetic resonance spectroscopy, we characterize liquid disordered bilayers formed by the naturally abundant 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine and different contents of a di-DHA glycero-phosphocholine, 22:6-22:6PC, from both a molecular/microscopic and supramolecular/mesoscopic viewpoint. We show that, below a threshold concentration of about 40% molar percent, incorporation of 22:6-22:6PC in the membrane increases the lipid dynamics slightly but sufficiently to promote the membrane deformation and increase of multilamellarity. Notably, beyond this threshold, 22:6-22:6PC disfavours the formation of lamellar phases, leading to a phase separation consisting mostly of small spherical particles that coexist with a minority portion of a lipid blob with water-filled cavities. Concurrently, from a molecular viewpoint, the polyunsaturated acyl chains tend to fold and expose the termini to the aqueous medium. We propose that this peculiar tendency is a key feature of the DHA-phospholipids making them able to modulate the local morphology of biomembranes.
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Affiliation(s)
- Augusta de Santis
- Department of Chemical Sciences, University of Naples Federico II, Naples, Italy.
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64
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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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65
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Cao Z, Wang X, Huang X, Mak HY. Are endoplasmic reticulum subdomains shaped by asymmetric distribution of phospholipids? Evidence from a C. elegans model system. Bioessays 2020; 43:e2000199. [PMID: 33169432 DOI: 10.1002/bies.202000199] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/13/2020] [Accepted: 09/18/2020] [Indexed: 12/19/2022]
Abstract
Physical contact between organelles are widespread, in part to facilitate the shuttling of protein and lipid cargoes for cellular homeostasis. How do protein-protein and protein-lipid interactions shape organelle subdomains that constitute contact sites? The endoplasmic reticulum (ER) forms extensive contacts with multiple organelles, including lipid droplets (LDs) that are central to cellular fat storage and mobilization. Here, we focus on ER-LD contacts that are highlighted by the conserved protein seipin, which promotes LD biogenesis and expansion. Seipin is enriched in ER tubules that form cage-like structures around a subset of LDs. Such enrichment is strongly dependent on polyunsaturated and cyclopropane fatty acids. Based on these findings, we speculate on molecular events that lead to the formation of seipin-positive peri-LD cages in which protein movement is restricted. We hypothesize that asymmetric distribution of specific phospholipids distinguishes cage membrane tubules from the bulk ER.
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Affiliation(s)
- Zhe Cao
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Xiaowei Wang
- Department of Chemistry, The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Xuhui Huang
- Department of Chemistry, The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Ho Yi Mak
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong SAR, China
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66
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Fernandez RF, Ellis JM. Acyl-CoA synthetases as regulators of brain phospholipid acyl-chain diversity. Prostaglandins Leukot Essent Fatty Acids 2020; 161:102175. [PMID: 33031993 PMCID: PMC8693597 DOI: 10.1016/j.plefa.2020.102175] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 07/22/2020] [Accepted: 09/09/2020] [Indexed: 12/20/2022]
Abstract
Each individual cell-type is defined by its distinct morphology, phenotype, molecular and lipidomic profile. The importance of maintaining cell-specific lipidomic profiles is exemplified by the numerous diseases, disorders, and dysfunctional outcomes that occur as a direct result of altered lipidome. Therefore, the mechanisms regulating cellular lipidome diversity play a role in maintaining essential biological functions. The brain is an organ particularly rich in phospholipids, the main constituents of cellular membranes. The phospholipid acyl-chain profile of membranes in the brain is rather diverse due in part to the high degree of cellular heterogeneity. These membranes and the acyl-chain composition of their phospholipids are highly regulated, but the mechanisms that confer this tight regulation are incompletely understood. A family of enzymes called acyl-CoA synthetases (ACSs) stands at a pinnacle step allowing influence over cellular acyl-chain selection and subsequent metabolic flux. ACSs perform the initial reaction for cellular fatty acid metabolism by ligating a Coenzyme A to a fatty acid which both traps a fatty acid within a cell and activates it for metabolism. The ACS family of enzymes is large and diverse consisting of 25-26 family members that are nonredundant, each with unique distribution across and within cell types, and differential fatty acid substrate preferences. Thus, ACSs confer a critical intracellular fatty acid selecting step in a cell-type dependent manner providing acyl-CoA moieties that serve as essential precursors for phospholipid synthesis and remodeling, and therefore serve as a key regulator of cellular membrane acyl-chain compositional diversity. Here we will discuss how the contribution of individual ACSs towards brain lipid metabolism has only just begun to be elucidated and discuss the possibilities for how ACSs may differentially regulate brain lipidomic diversity.
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Affiliation(s)
- Regina F Fernandez
- Department of Physiology and East Carolina Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, NC, United States
| | - Jessica M Ellis
- Department of Physiology and East Carolina Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, NC, United States.
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67
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Foley S, Miller E, Braziel S, Lee S. Molecular organization in mixed SOPC and SDPC model membranes: Water permeability studies of polyunsaturated lipid bilayers. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183365. [DOI: 10.1016/j.bbamem.2020.183365] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 05/18/2020] [Accepted: 05/20/2020] [Indexed: 12/16/2022]
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68
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Borges-Araújo L, Fernandes F. Structure and Lateral Organization of Phosphatidylinositol 4,5-bisphosphate. Molecules 2020; 25:molecules25173885. [PMID: 32858905 PMCID: PMC7503891 DOI: 10.3390/molecules25173885] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/22/2020] [Accepted: 08/23/2020] [Indexed: 02/07/2023] Open
Abstract
Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) is a minor but ubiquitous component of the inner leaflet of the plasma membrane of eukaryotic cells. However, due to its particular complex biophysical properties, it stands out from its neighboring lipids as one of the most important regulators of membrane-associated signaling events. Despite its very low steady-state concentration, PI(4,5)P2 is able to engage in a multitude of simultaneous cellular functions that are temporally and spatially regulated through the presence of localized transient pools of PI(4,5)P2 in the membrane. These pools are crucial for the recruitment, activation, and organization of signaling proteins and consequent regulation of downstream signaling. The present review showcases some of the most important PI(4,5)P2 molecular and biophysical properties as well as their impact on its membrane dynamics, lateral organization, and interactions with other biochemical partners.
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Affiliation(s)
- Luís Borges-Araújo
- iBB—Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisbon, Portugal;
- Correspondence:
| | - Fabio Fernandes
- iBB—Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisbon, Portugal;
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisbon, Portugal
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69
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Bhatia T, Robinson T, Dimova R. Membrane permeability to water measured by microfluidic trapping of giant vesicles. SOFT MATTER 2020; 16:7359-7369. [PMID: 32696791 DOI: 10.1039/d0sm00155d] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We use a microfluidic method to estimate the water permeability coefficient (p) of membranes. As model lipid membranes we employ giant unilamellar vesicles (GUVs) composed of palmitoyloleoyl phosphatidylcholine and cholesterol (10 mol%). We have developed a microfluidic device with multiple chambers to trap GUVs and allow controlled osmotic exchange. Each chamber has a ring-shaped pressure-controlled valve which upon closure allows isolation of the GUVs in a defined volume. Opening the valves leads to a rapid fluid exchange between the trapping region and the microchannel network outside, thus allowing precise control over solution concentration around the GUVs contrary to other experimental approaches for permeability measurements reported in the literature. The area and volume changes of individual vesicles are monitored with confocal microscopy. The solute concentration in the immediate vicinity of the GUVs, and thus the concentration gradient across the membrane, is independently assessed. The data are well fitted by a simple model for water permeability which assumes that the rate of change in volume of a GUV per unit area is linearly proportional to concentration difference with permeability as the proportionality constant. Experiments of GUV osmotic deflation with hypertonic solutions yield the permeability of POPC/cholesterol 9/1 membranes to be p = 15.7 ± 5.5 μm s-1. For comparison, we also show results using two other approaches, which either do not take into account local concentration changes and/or do not resolve the precise vesicle shape. We point out the errors associated with these limitations. Finally, we also demonstrate the applicability of the microfluidic device for studying the dynamics of vesicles under flow.
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Affiliation(s)
- Tripta Bhatia
- Theory & Biosystems, Max Planck Institute of Colloids and Interfaces (MPIKG), 14424 Potsdam, Germany.
| | - Tom Robinson
- Theory & Biosystems, Max Planck Institute of Colloids and Interfaces (MPIKG), 14424 Potsdam, Germany.
| | - Rumiana Dimova
- Theory & Biosystems, Max Planck Institute of Colloids and Interfaces (MPIKG), 14424 Potsdam, Germany.
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70
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Mono- and Poly-unsaturated Phosphatidic Acid Regulate Distinct Steps of Regulated Exocytosis in Neuroendocrine Cells. Cell Rep 2020; 32:108026. [DOI: 10.1016/j.celrep.2020.108026] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 06/16/2020] [Accepted: 07/21/2020] [Indexed: 12/21/2022] Open
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71
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Rabia M, Leuzy V, Soulage C, Durand A, Fourmaux B, Errazuriz-Cerda E, Köffel R, Draeger A, Colosetti P, Jalabert A, Di Filippo M, Villard-Garon A, Bergerot C, Luquain-Costaz C, Moulin P, Rome S, Delton I, Hullin-Matsuda F. Bis(monoacylglycero)phosphate, a new lipid signature of endosome-derived extracellular vesicles. Biochimie 2020; 178:26-38. [PMID: 32659447 DOI: 10.1016/j.biochi.2020.07.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 06/29/2020] [Accepted: 07/08/2020] [Indexed: 01/05/2023]
Abstract
Bis(monoacylglycero)phosphate (BMP), also known as lysobisphosphatidic acid (LBPA), is a phospholipid specifically enriched in the late endosome-lysosome compartment playing a crucial role for the fate of endocytosed components. Due to its presence in extracellular fluids during diseases associated with endolysosomal dysfunction, it is considered as a possible biomarker of disorders such as genetic lysosomal storage diseases and cationic amphiphilic drug-induced phospholipidosis. However, there is no true validation of this biomarker in human studies, nor a clear identification of the carrier of this endolysosome-specific lipid in biofluids. The present study demonstrates that in absence of any sign of renal failure, BMP, especially all docosahexaenoyl containing species, are significantly increased in the urine of patients treated with the antiarrhythmic drug amiodarone. Such urinary BMP increase could reflect a generalized drug-induced perturbation of the endolysosome compartment as observed in vitro with amiodarone-treated human macrophages. Noteworthy, BMP was associated with extracellular vesicles (EVs) isolated from human urines and extracellular medium of human embryonic kidney HEK293 cells and co-localizing with classical EV protein markers CD63 and ALIX. In the context of drug-induced endolysosomal dysfunction, increased BMP-rich EV release could be useful to remove excess of undigested material. This first human pilot study not only reveals BMP as a urinary biomarker of amiodarone-induced endolysosomal dysfunction, but also highlights its utility to prove the endosomal origin of EVs, also named as exosomes. This peculiar lipid already known as a canonical late endosome-lysosome marker, may be thus considered as a new lipid marker of urinary exosomes.
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Affiliation(s)
- Maxence Rabia
- Univ-Lyon, CarMeN Laboratory, Inserm U1060, INRAe U1397, INSA Lyon, Villeurbanne, France
| | - Valentin Leuzy
- Univ-Lyon, CarMeN Laboratory, Inserm U1060, INRAe U1397, INSA Lyon, Villeurbanne, France
| | - Christophe Soulage
- Univ-Lyon, CarMeN Laboratory, Inserm U1060, INRAe U1397, INSA Lyon, Villeurbanne, France
| | - Annie Durand
- Univ-Lyon, CarMeN Laboratory, Inserm U1060, INRAe U1397, INSA Lyon, Villeurbanne, France
| | - Baptiste Fourmaux
- Univ-Lyon, CarMeN Laboratory, Inserm U1060, INRAe U1397, INSA Lyon, Villeurbanne, France; Functional Lipidomics Platform, CarMeN Laboratory / IMBL-INSA Lyon, 69621, Villeurbanne Cedex, France
| | | | - René Köffel
- Department of Cell Biology, Institute of Anatomy, University of Bern, Bern, Switzerland
| | - Annette Draeger
- Department of Cell Biology, Institute of Anatomy, University of Bern, Bern, Switzerland
| | - Pascal Colosetti
- Univ-Lyon, CarMeN Laboratory, Inserm U1060, INRAe U1397, INSA Lyon, Villeurbanne, France
| | - Audrey Jalabert
- Univ-Lyon, CarMeN Laboratory, Inserm U1060, INRAe U1397, INSA Lyon, Villeurbanne, France
| | - Mathilde Di Filippo
- Univ-Lyon, CarMeN Laboratory, Inserm U1060, INRAe U1397, INSA Lyon, Villeurbanne, France; Department of Biochemistry and Molecular Biology, Centre de Biologie et de Pathologie Est, Hospices Civils de Lyon, Bron, France
| | - Audrey Villard-Garon
- Department of Endocrinology, Hôpital Cardiovasculaire Louis Pradel, Hospices Civils de Lyon, Lyon, Bron, France
| | - Cyrille Bergerot
- Department of Cardiology, Hôpital Cardiovasculaire Louis Pradel, Hospices Civils de Lyon, Lyon, Bron, France
| | - Céline Luquain-Costaz
- Univ-Lyon, CarMeN Laboratory, Inserm U1060, INRAe U1397, INSA Lyon, Villeurbanne, France
| | - Philippe Moulin
- Univ-Lyon, CarMeN Laboratory, Inserm U1060, INRAe U1397, INSA Lyon, Villeurbanne, France; Department of Endocrinology, Hôpital Cardiovasculaire Louis Pradel, Hospices Civils de Lyon, Lyon, Bron, France
| | - Sophie Rome
- Univ-Lyon, CarMeN Laboratory, Inserm U1060, INRAe U1397, INSA Lyon, Villeurbanne, France
| | - Isabelle Delton
- Univ-Lyon, CarMeN Laboratory, Inserm U1060, INRAe U1397, INSA Lyon, Villeurbanne, France
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72
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Sato A, Ohhara Y, Miura S, Yamakawa-Kobayashi K. The presence of odd-chain fatty acids in Drosophila phospholipids. Biosci Biotechnol Biochem 2020; 84:2139-2148. [PMID: 32633700 DOI: 10.1080/09168451.2020.1790337] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Most fatty acids in phospholipids and other lipid species carry an even number of carbon atoms. Also odd-chain fatty acids (OCFAs), such as C15:0 and C17:0, are widespread throughout the living organism. However, the qualitative and quantitative profiles of OCFAs-containing lipids in living organisms remain unclear. Here, we show that OCFAs are present in Drosophila phosphatidylcholine (PC) and phosphatidylethanolamine (PE) and that their level increases in accordance with progression of growth. Furthermore, we found that food-derived propionic acid/propanoic acid (C3:0) is utilized for production of OCFA-containing PC and PE. This study provides the basis for understanding in vivo function of OCFA-containing phospholipids in development and lipid homeostasis.
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Affiliation(s)
- Ayaka Sato
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka , Shizuoka, Japan
| | - Yuya Ohhara
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka , Shizuoka, Japan.,School of Food and Nutritional Sciences, University of Shizuoka , Shizuoka, Japan.,Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba , Tsukuba, Ibaraki, Japan
| | - Shinji Miura
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka , Shizuoka, Japan.,School of Food and Nutritional Sciences, University of Shizuoka , Shizuoka, Japan
| | - Kimiko Yamakawa-Kobayashi
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka , Shizuoka, Japan.,School of Food and Nutritional Sciences, University of Shizuoka , Shizuoka, Japan
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73
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Faugeras V, Duclos O, Bazile D, Thiam AR. Membrane determinants for the passive translocation of analytes through droplet interface bilayers. SOFT MATTER 2020; 16:5970-5980. [PMID: 32543614 DOI: 10.1039/d0sm00667j] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Understanding how small molecules cross cell membranes is crucial to pharmaceutics. Several methods have been developed to evaluate such a process, but they need improvement since many false-positive candidates are often selected. Robust tools enabling rapid and reproducible screening can increase confidence on hits, and artificial membranes based on droplet interface bilayers (DIBs) offer this possibility. DIBs consist in the adhesion of two phospholipid-covered water-in-oil droplets which reproduce a bilayer. By having donor and acceptor droplets, the permeability of an analyte can be studied. However, the relevance of this system relies on the comprehension of how well the physical chemistry of the produced bilayer recapitulates the behavior of cell membranes. This information is missing, and we address it here. Taking small fluorophores as model analytes, we studied their permeation through DIBs made of a wide range of phospholipids. We found that both the phospholipid acyl chain and polar head affect permeability. Overall, these parameters impact the phospholipid shape and thereupon the membrane lateral pressure, which is a major factor modulating with permeability in our system. These results depend on the nature of the chosen oil. We thereupon identified relevant physical chemistry conditions that best mimic the compactness and subsequent permeability of biological membranes.
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Affiliation(s)
- Vincent Faugeras
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Paris, France.
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74
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Ohashi Y, Tremel S, Masson GR, McGinney L, Boulanger J, Rostislavleva K, Johnson CM, Niewczas I, Clark J, Williams RL. Membrane characteristics tune activities of endosomal and autophagic human VPS34 complexes. eLife 2020; 9:58281. [PMID: 32602837 PMCID: PMC7326497 DOI: 10.7554/elife.58281] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Accepted: 06/04/2020] [Indexed: 12/14/2022] Open
Abstract
The lipid kinase VPS34 orchestrates diverse processes, including autophagy, endocytic sorting, phagocytosis, anabolic responses and cell division. VPS34 forms various complexes that help adapt it to specific pathways, with complexes I and II being the most prominent ones. We found that physicochemical properties of membranes strongly modulate VPS34 activity. Greater unsaturation of both substrate and non-substrate lipids, negative charge and curvature activate VPS34 complexes, adapting them to their cellular compartments. Hydrogen/deuterium exchange mass spectrometry (HDX-MS) of complexes I and II on membranes elucidated structural determinants that enable them to bind membranes. Among these are the Barkor/ATG14L autophagosome targeting sequence (BATS), which makes autophagy-specific complex I more active than the endocytic complex II, and the Beclin1 BARA domain. Interestingly, even though Beclin1 BARA is common to both complexes, its membrane-interacting loops are critical for complex II, but have only a minor role for complex I.
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Affiliation(s)
- Yohei Ohashi
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, United Kingdom
| | - Shirley Tremel
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, United Kingdom
| | - Glenn Robert Masson
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, United Kingdom
| | - Lauren McGinney
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, United Kingdom
| | - Jerome Boulanger
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, United Kingdom
| | - Ksenia Rostislavleva
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, United Kingdom
| | - Christopher M Johnson
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, United Kingdom
| | | | | | - Roger L Williams
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, United Kingdom
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75
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The roles of the diversity of amphipathic lipids in shaping membranes by membrane-shaping proteins. Biochem Soc Trans 2020; 48:837-851. [PMID: 32597479 DOI: 10.1042/bst20190376] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 06/02/2020] [Accepted: 06/05/2020] [Indexed: 12/23/2022]
Abstract
Lipid compositions of cells differ according to cell types and intracellular organelles. Phospholipids are major cell membrane lipids and have hydrophilic head groups and hydrophobic fatty acid tails. The cellular lipid membrane without any protein adapts to spherical shapes, and protein binding to the membrane is thought to be required for shaping the membrane for various cellular events. Until recently, modulation of cellular lipid membranes was initially shown to be mediated by proteins recognizing lipid head groups, including the negatively charged ones of phosphatidylserine and phosphoinositides. Recent studies have shown that the abilities of membrane-deforming proteins are also regulated by the composition of fatty acid tails, which cause different degrees of packing defects. The binding of proteins to cellular lipid membranes is affected by the packing defects, presumably through modulation of their interactions with hydrophobic amino acid residues. Therefore, lipid composition can be characterized by both packing defects and charge density. The lipid composition regarding fatty acid tails affects membrane bending via the proteins with amphipathic helices, including those with the ArfGAP1 lipid packing sensor (ALPS) motif and via membrane-deforming proteins with structural folding, including those with the Bin-Amphiphysin-Rvs167 (BAR) domains. This review focuses on how the fatty acid tails, in combination with the head groups of phospholipids, affect protein-mediated membrane deformation.
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76
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Bozelli JC, Epand RM. Specificity of Acyl Chain Composition of Phosphatidylinositols. Proteomics 2020; 19:e1900138. [PMID: 31381272 DOI: 10.1002/pmic.201900138] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 07/30/2019] [Indexed: 01/15/2023]
Abstract
Phosphatidylinositol (PI) lipids have a predominance of a single molecular species present through the organism. In healthy mammals this molecular species is 1-stearoyl-2-arachidonoyl (18:0/20:4) PI. Although the importance of PI lipids for cell physiology has long been appreciated, less is known about the biological role of enriching PI lipids with 18:0/20:4 acyl chains. In conditions with dysfunctional lipid metabolism, the predominance of 18:0/20:4 acyl chains is lost. Recently, molecular mechanisms underpinning the enrichment or alteration of these acyl chains in PI lipids have begun to emerge. In the majority of the cases a common feature is the presence of enzymes bearing substrate acyl chain specificity. However, in cancer cells, it has been shown that one (not the only) of the mechanisms responsible for the loss in this acyl chain enrichment is mutation on the transcription factor p53 gene, which is one of the most highly mutated genes in cancers. There is a compelling need for a global picture of the specificity of the acyl chain composition of PIs. This can be possible once high-resolution spatio-temporal information is gathered in a cellular context; which can ultimately lead to potential novel targets to combat conditions with altered PI acyl chain profiles.
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Affiliation(s)
- José Carlos Bozelli
- Department of Biochemistry and Biomedical Sciences, McMaster University Health Sciences Centre, Hamilton, Ontario, L8S 4K1, Canada
| | - Richard M Epand
- Department of Biochemistry and Biomedical Sciences, McMaster University Health Sciences Centre, Hamilton, Ontario, L8S 4K1, Canada
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77
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In Vivo Assessment of Thermosensitive Liposomes for the Treatment of Port Wine Stains by Antifibrinolytic Site-Specific Pharmaco-Laser Therapy. Pharmaceutics 2020; 12:pharmaceutics12060591. [PMID: 32630457 PMCID: PMC7356038 DOI: 10.3390/pharmaceutics12060591] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 06/13/2020] [Accepted: 06/22/2020] [Indexed: 01/10/2023] Open
Abstract
Antifibrinolytic site-specific pharmaco-laser therapy (SSPLT) is an experimental treatment modality for refractory port wine stains (PWS). Conceptually, antifibrinolytic drugs encapsulated in thermosensitive liposomes are delivered to thrombi that form in semi-photocoagulated PWS blood vessels after conventional laser treatment. Local release of antifibrinolytics is induced by mild hyperthermia, resulting in hyperthrombosis and complete occlusion of the target blood vessel (clinical endpoint). In this study, 20 thermosensitive liposomal formulations containing tranexamic acid (TA) were assayed for physicochemical properties, TA:lipid ratio, encapsulation efficiency, and endovesicular TA concentration. Two candidate formulations (DPPC:DSPE-PEG, DPPC:MPPC:DSPE-PEG) were selected based on optimal properties and analyzed for heat-induced TA release at body temperature (T), phase transition temperature (Tm), and at T > Tm. The effect of plasma on liposomal stability at 37 °C was determined, and the association of liposomes with platelets was examined by flow cytometry. The accumulation of PEGylated phosphocholine liposomes in laser-induced thrombi was investigated in a hamster dorsal skinfold model and intravital fluorescence microscopy. Both formulations did not release TA at 37 °C. Near-complete TA release was achieved at Tm within 2.0–2.5 min of heating, which was accelerated at T > Tm. Plasma exerted a stabilizing effect on both formulations. Liposomes showed mild association with platelets. Despite positive in vitro results, fluorescently labeled liposomes did not sufficiently accumulate in laser-induced thrombi in hamsters to warrant their use in antifibrinolytic SSPLT, which can be solved by coupling thrombus-targeting ligands to the liposomes.
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78
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Comprehensive Characterization of Phospholipid Isomers in Human Platelets. JOURNAL OF ANALYSIS AND TESTING 2020. [DOI: 10.1007/s41664-020-00137-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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79
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Zhang W, Shang B, Ouyang Z, Xia Y. Enhanced Phospholipid Isomer Analysis by Online Photochemical Derivatization and RPLC-MS. Anal Chem 2020; 92:6719-6726. [PMID: 32271544 DOI: 10.1021/acs.analchem.0c00690] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Mapping the complete molecular composition of a lipidome is considered an important goal of lipidomics for unraveling pathways and mechanisms behind lipid homeostasis. Conventional dissociation methods of mass spectrometry (MS) usually cannot give detailed structural information on lipids such as locations of carbon-carbon double bonds (C═C) in acyl chains. Double-bond derivatization via the Paternò-Büchi (PB) reaction has been demonstrated as a simple and highly efficient method for identification of C═C locations of different classes of lipids when paired with tandem mass spectrometry (MS/MS). In this work, reversed-phase lipid chromatography (RPLC)-MS was coupled with an online PB reaction to achieve enhanced analysis of isomers and isobars of phospholipids. A new acetone-containing mobile phase was developed that showed good elution performance for the separation of phospholipids by C18 columns. An improved flow microreactor was developed, enabling online derivatization of phospholipid C═C in 20 s. The workflow of RPLC-PB-MS/MS was developed and optimized for identification of C═C locations in isobaric ether-linked and diacyl phospholipids, 13C isobars, and acyl chain isomers in biological lipid extracts. Separation and identification of C═C locations of cis/trans phospholipid isomers were achieved for lipid standards. The incorporation of the PB reaction into the RPLC-MS workflow enabled analysis of phospholipid isomers and isobars with high confidence, demonstrating its potential for high-throughput phospholipid identification from complex mixtures.
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Affiliation(s)
- Wenpeng Zhang
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biological, Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.,Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Bing Shang
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biological, Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China
| | - Zheng Ouyang
- State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments, Tsinghua University, Beijing 100084, P. R. China
| | - Yu Xia
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biological, Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China
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80
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Nguyen HC, Talledge N, McCullough J, Sharma A, Moss FR, Iwasa JH, Vershinin MD, Sundquist WI, Frost A. Membrane constriction and thinning by sequential ESCRT-III polymerization. Nat Struct Mol Biol 2020; 27:392-399. [PMID: 32251413 PMCID: PMC7343221 DOI: 10.1038/s41594-020-0404-x] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 03/05/2020] [Indexed: 01/04/2023]
Abstract
The endosomal sorting complexes required for transport (ESCRTs) mediate diverse membrane remodeling events. These typically require ESCRT-III proteins to stabilize negatively curved membranes; however, recent work has indicated that certain ESCRT-IIIs also participate in positive-curvature membrane-shaping reactions. ESCRT-IIIs polymerize into membrane-binding filaments, but the structural basis for negative versus positive membrane remodeling by these proteins remains poorly understood. To learn how certain ESCRT-IIIs shape positively curved membranes, we determined structures of human membrane-bound CHMP1B-only, membrane-bound CHMP1B + IST1, and IST1-only filaments by cryo-EM. Our structures show how CHMP1B first polymerizes into a single-stranded helical filament, shaping membranes into moderate-curvature tubules. Subsequently, IST1 assembles a second strand on CHMP1B, further constricting the membrane tube and reducing its diameter nearly to the fission point. Each step of constriction thins the underlying bilayer, lowering the barrier to membrane fission. Our structures reveal how a two-component, sequential polymerization mechanism drives membrane tubulation, constriction and bilayer thinning.
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Affiliation(s)
- Henry C Nguyen
- Department of Biochemistry & Biophysics, University of California, San Francisco, San Francisco, CA, USA
| | - Nathaniel Talledge
- Department of Biochemistry & Biophysics, University of California, San Francisco, San Francisco, CA, USA
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
- Institute for Molecular Virology, University of Minnesota-Twin Cities, Minneapolis, MN, USA
| | - John McCullough
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - Abhimanyu Sharma
- Department of Physics & Astronomy, University of Utah, Salt Lake City, UT, USA
| | - Frank R Moss
- Department of Biochemistry & Biophysics, University of California, San Francisco, San Francisco, CA, USA
| | - Janet H Iwasa
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - Michael D Vershinin
- Department of Physics & Astronomy, University of Utah, Salt Lake City, UT, USA
- Department of Biology, University of Utah, Salt Lake City, UT, USA
- Center for Cell and Genome Science, University of Utah, Salt Lake City, UT, USA
| | - Wesley I Sundquist
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA.
| | - Adam Frost
- Department of Biochemistry & Biophysics, University of California, San Francisco, San Francisco, CA, USA.
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA.
- Chan Zuckerberg Biohub, San Francisco, CA, USA.
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81
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Levental KR, Malmberg E, Symons JL, Fan YY, Chapkin RS, Ernst R, Levental I. Lipidomic and biophysical homeostasis of mammalian membranes counteracts dietary lipid perturbations to maintain cellular fitness. Nat Commun 2020; 11:1339. [PMID: 32165635 PMCID: PMC7067841 DOI: 10.1038/s41467-020-15203-1] [Citation(s) in RCA: 105] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 02/21/2020] [Indexed: 11/29/2022] Open
Abstract
Proper membrane physiology requires maintenance of biophysical properties, which must be buffered from external perturbations. While homeostatic adaptation of membrane fluidity to temperature variation is a ubiquitous feature of ectothermic organisms, such responsive membrane adaptation to external inputs has not been directly observed in mammals. Here, we report that challenging mammalian membranes by dietary lipids leads to robust lipidomic remodeling to preserve membrane physical properties. Specifically, exogenous polyunsaturated fatty acids are rapidly incorporated into membrane lipids, inducing a reduction in membrane packing. These effects are rapidly compensated both in culture and in vivo by lipidome-wide remodeling, most notably upregulation of saturated lipids and cholesterol, resulting in recovery of membrane packing and permeability. Abrogation of this response results in cytotoxicity when membrane homeostasis is challenged by dietary lipids. These results reveal an essential mammalian mechanism for membrane homeostasis wherein lipidome remodeling in response to dietary lipid inputs preserves functional membrane phenotypes. Proper membrane physiology requires maintenance of a narrow range of physicochemical properties, which must be buffered from external perturbations. Here, authors report lipidomic remodeling to preserve membrane physical properties upon exogenous polyunsaturated fatty acids exposure.
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Affiliation(s)
- Kandice R Levental
- Department of Integrative Biology & Pharmacology, University of Texas Health Science Center at Houston, Houston, TX, USA.
| | - Eric Malmberg
- Department of Integrative Biology & Pharmacology, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Jessica L Symons
- Department of Integrative Biology & Pharmacology, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Yang-Yi Fan
- Program in Integrative Nutrition & Complex Diseases and Department of Nutrition, Texas A&M University, College Station, TX, USA
| | - Robert S Chapkin
- Program in Integrative Nutrition & Complex Diseases and Department of Nutrition, Texas A&M University, College Station, TX, USA
| | - Robert Ernst
- Department of Medical Biochemistry & Molecular Biology, Medical Faculty, Saarland University, Homburg, Germany
| | - Ilya Levental
- Department of Integrative Biology & Pharmacology, University of Texas Health Science Center at Houston, Houston, TX, USA.
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82
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Valanciunaite J, Kempf E, Seki H, Danylchuk DI, Peyriéras N, Niko Y, Klymchenko AS. Polarity Mapping of Cells and Embryos by Improved Fluorescent Solvatochromic Pyrene Probe. Anal Chem 2020; 92:6512-6520. [DOI: 10.1021/acs.analchem.0c00023] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Jurga Valanciunaite
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, 74 route du Rhin, 67401, Illkirch, France
| | - Emilie Kempf
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, 74 route du Rhin, 67401, Illkirch, France
| | - Hitomi Seki
- Research and Education Faculty, Multidisciplinary Science Cluster, Interdisciplinary Science Unit, Kochi University, 2-5-1, Akebono-cho, Kochi-shi, Kochi, 780-8520, Japan
| | - Dmytro I. Danylchuk
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, 74 route du Rhin, 67401, Illkirch, France
| | - Nadine Peyriéras
- CNRS USR3695 BioEmergences, Avenue de la Terrasse, 91190 Gif-sur-Yvette, France
| | - Yosuke Niko
- Research and Education Faculty, Multidisciplinary Science Cluster, Interdisciplinary Science Unit, Kochi University, 2-5-1, Akebono-cho, Kochi-shi, Kochi, 780-8520, Japan
| | - Andrey S. Klymchenko
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, 74 route du Rhin, 67401, Illkirch, France
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83
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Tiberti ML, Antonny B, Gautier R. The transbilayer distribution of polyunsaturated phospholipids determines their facilitating effect on membrane deformation. SOFT MATTER 2020; 16:1722-1730. [PMID: 31916552 DOI: 10.1039/c9sm02107h] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In the cell, membrane deformation and fission (collectively referred to as 'budding') is driven by specific protein machineries but is also influenced by lipid composition. We previously reported that phospholipids with polyunsaturated acyl chains facilitate membrane budding because they adapt their shape to membrane curvature, thereby decreasing membrane bending rigidity. The facilitating effect of polyunsaturated lipids was observed in experiments and simulations performed on membranes where the two bilayer leaflets had the same lipid composition. However, biological membranes are generally asymmetric. Here, we present coarse-grained molecular dynamics simulations on asymmetric phospholipid bilayers undergoing deformation via a pulling force along the bilayer normal. One leaflet contains monounsaturated C18:0-C18:1-phospholipids, whereas the opposite leaflet contains polyunsaturated C18:0-C22:6-phospholipids. When present in the monolayer orientated towards the pulling force and thereby in the convex face of the forming tube, C18:0-C22:6-phospholipids facilitate membrane tubulation. In contrast, C18:0-C22:6-phospholipids in the concave face of the tube have no effect. Analysis of lipid shape indicates that these contrasting effects arise from the superior ability of polyunsaturated phospholipids to swell in the convex leaflet, whereas mono and polyunsaturated phospholipids behave similarly in the concave leaflet. The leaflet-dependent effect of polyunsaturated phospholipids matches well their asymmetric distribution in biological membranes, notably in synaptic vesicles, which are produced by the fastest budding event in the body.
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Affiliation(s)
- Marion L Tiberti
- Université Côte d'Azur et CNRS, IPMC, 660 route des lucioles, 06560 Valbonne, France.
| | - Bruno Antonny
- Université Côte d'Azur et CNRS, IPMC, 660 route des lucioles, 06560 Valbonne, France.
| | - Romain Gautier
- Université Côte d'Azur et CNRS, IPMC, 660 route des lucioles, 06560 Valbonne, France.
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84
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Makarova M, Peter M, Balogh G, Glatz A, MacRae JI, Lopez Mora N, Booth P, Makeyev E, Vigh L, Oliferenko S. Delineating the Rules for Structural Adaptation of Membrane-Associated Proteins to Evolutionary Changes in Membrane Lipidome. Curr Biol 2020; 30:367-380.e8. [PMID: 31956022 PMCID: PMC6997885 DOI: 10.1016/j.cub.2019.11.043] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 10/31/2019] [Accepted: 11/13/2019] [Indexed: 01/01/2023]
Abstract
Membrane function is fundamental to life. Each species explores membrane lipid diversity within a genetically predefined range of possibilities. How membrane lipid composition in turn defines the functional space available for evolution of membrane-centered processes remains largely unknown. We address this fundamental question using related fission yeasts Schizosaccharomyces pombe and Schizosaccharomyces japonicus. We show that, unlike S. pombe that generates membranes where both glycerophospholipid acyl tails are predominantly 16-18 carbons long, S. japonicus synthesizes unusual "asymmetrical" glycerophospholipids where the tails differ in length by 6-8 carbons. This results in stiffer bilayers with distinct lipid packing properties. Retroengineered S. pombe synthesizing the S.-japonicus-type phospholipids exhibits unfolded protein response and downregulates secretion. Importantly, our protein sequence comparisons and domain swap experiments support the hypothesis that transmembrane helices co-evolve with membranes, suggesting that, on the evolutionary scale, changes in membrane lipid composition may necessitate extensive adaptation of the membrane-associated proteome.
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Affiliation(s)
- Maria Makarova
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Randall Centre for Cell and Molecular Biophysics, School of Basic and Medical Biosciences, King's College London, Guy's Campus, London SE1 1UL, UK
| | - Maria Peter
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Temesvári krt. 62, Szeged 6726, Hungary
| | - Gabor Balogh
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Temesvári krt. 62, Szeged 6726, Hungary
| | - Attila Glatz
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Temesvári krt. 62, Szeged 6726, Hungary
| | - James I MacRae
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Nestor Lopez Mora
- Department of Chemistry, King's College London, Britannia House, London SE1 1DB, UK
| | - Paula Booth
- Department of Chemistry, King's College London, Britannia House, London SE1 1DB, UK
| | - Eugene Makeyev
- MRC Centre for Developmental Neurobiology, King's College London, Guy's Campus, London SE1 1UL, UK
| | - Laszlo Vigh
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Temesvári krt. 62, Szeged 6726, Hungary
| | - Snezhana Oliferenko
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Randall Centre for Cell and Molecular Biophysics, School of Basic and Medical Biosciences, King's College London, Guy's Campus, London SE1 1UL, UK.
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85
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Abstract
Due to the heterogenous lipid environment in which integral membrane proteins are embedded, they should follow a set of assembly rules, which govern transmembrane protein folding and topogenesis accordingly to a given lipid profile. Recombinant strains of bacteria have been engineered to have different membrane phospholipid compositions by molecular genetic manipulation of endogenous and foreign genes encoding lipid biosynthetic enzymes. Such strains provide a means to investigate the in vivo role of lipids in many different aspects of membrane function, folding and biogenesis. In vitro and in vivo studies established a function of lipids as molecular chaperones and topological determinants specifically assisting folding and topogenesis of membrane proteins. These results led to the extension of the Positive Inside Rule to Charge Balance Rule, which incorporates a role for lipid-protein interactions in determining membrane protein topological organization at the time of initial membrane insertion and dynamically after initial assembly. Membrane protein topogenesis appears to be a thermodynamically driven process in which lipid-protein interactions affect the potency of charged amino acid residues as topological signals. Dual topology for a membrane protein can be established during initial assembly where folding intermediates in multiple topological conformations are in rapid equilibrium (thus separated by a low activation energy), which is determined by the lipid environment. Post-assembly changes in lipid composition or post-translational modifications can trigger a reorganization of protein topology by inducing destabilization and refolding of a membrane protein. The lipid-dependent dynamic nature of membrane protein organization provides a novel means of regulating protein function.
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86
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Lactobacillus salivarius BGHO1 and Lactobacillus reuteri BGGO6-55 modify nutritive profile of Artemia franciscana nauplii in a strain ratio, dose and application timing-dependent manner. Anim Feed Sci Technol 2020. [DOI: 10.1016/j.anifeedsci.2019.114356] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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87
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Skowronska-Krawczyk D, Budin I. Aging membranes: Unexplored functions for lipids in the lifespan of the central nervous system. Exp Gerontol 2019; 131:110817. [PMID: 31862420 DOI: 10.1016/j.exger.2019.110817] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 12/11/2019] [Accepted: 12/16/2019] [Indexed: 10/25/2022]
Abstract
Lipids constitute a significant group of biological metabolites and the building blocks of all cell membranes. The abundance and stoichiometries of different lipid species are known to vary across the lifespan and metabolic state, yet the functional effects of these changes have been challenging to understand. Here we review the potentially powerful intersection of lipid metabolism, which determines membrane composition, and aging. We first introduce several key lipid classes that are associated with aging and aging-related disease, where they are found in organisms, and how they act on membrane structure and function. Instead of neutral lipids, which have primary roles in energy storage and homeostasis, we review known functions for polar lipids that control the physicochemical properties of cell membranes. We then focus on aging processes in the central nervous system (CNS), which is enriched in lipids and is highly dependent on membrane structure for function. Recent studies show how lipids act not just as biomarkers of aging and associated changes in the CNS, but as direct mediators of these processes. As a model system, we explore how fatty acid composition in the retina impact aging and aging-related disease. We propose that the biophysical effects of membrane structure on fundamental eukaryotic processes - mitochondrial respiration and autophagy - provide avenues by which lipid dysregulation can accelerate aging processes. Finally, we lay out ways in which an increased understanding of lipid membrane biology can be applied to studies of aging and lifespan.
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Affiliation(s)
- Dorota Skowronska-Krawczyk
- Viterbi Family Department of Ophthalmology, School do Medicine, University of California San Diego, La Jolla, CA 92093, USA.
| | - Itay Budin
- Department of Chemistry & Biochemistry, University of California San Diego, La Jolla, CA 92093, USA.
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88
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Varga K, Jiang ZJ, Gong LW. Phosphatidylserine is critical for vesicle fission during clathrin-mediated endocytosis. J Neurochem 2019; 152:48-60. [PMID: 31587282 DOI: 10.1111/jnc.14886] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 09/25/2019] [Accepted: 10/01/2019] [Indexed: 12/11/2022]
Abstract
Phosphatidylserine (PS), a negatively charged phospholipid present predominantly at the inner leaflet of the plasma membrane, has been widely implicated in many cellular processes including membrane trafficking. Along this line, PS has been demonstrated to be important for endocytosis, however, the involved mechanisms remain uncertain. By monitoring clathrin-mediated endocytosis (CME) of single vesicles in mouse chromaffin cells using cell-attached capacitance measurements that offer millisecond time resolution, we demonstrate in the present study that the fission-pore duration is reduced by PS addition, indicating a stimulatory role of PS in regulating the dynamics of vesicle fission during CME. Furthermore, our results show that the PS-mediated effect on the fission-pore duration is Ca2+ -dependent and abolished in the absence of synaptotagmin 1 (Syt1), implying that Syt1 is necessary for the stimulatory role of PS in vesicle fission during CME. Consistently, a Syt1 mutant with a defective PS-Syt1 interaction increases the fission-pore duration. Taken together, our study suggests that PS-Syt1 interaction may be critical in regulating fission dynamics during CME.
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Affiliation(s)
- Kelly Varga
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, USA.,Department of Biological Sciences, University of North Texas at Dallas, Dallas, Texas, USA
| | - Zhong-Jiao Jiang
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Liang-Wei Gong
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
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89
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de Mendoza D, Pilon M. Control of membrane lipid homeostasis by lipid-bilayer associated sensors: A mechanism conserved from bacteria to humans. Prog Lipid Res 2019; 76:100996. [DOI: 10.1016/j.plipres.2019.100996] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 06/25/2019] [Accepted: 06/28/2019] [Indexed: 12/31/2022]
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90
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Steinkühler J, Sezgin E, Urbančič I, Eggeling C, Dimova R. Mechanical properties of plasma membrane vesicles correlate with lipid order, viscosity and cell density. Commun Biol 2019; 2:337. [PMID: 31531398 PMCID: PMC6744421 DOI: 10.1038/s42003-019-0583-3] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 08/15/2019] [Indexed: 11/08/2022] Open
Abstract
Regulation of plasma membrane curvature and composition governs essential cellular processes. The material property of bending rigidity describes the energetic cost of membrane deformations and depends on the plasma membrane molecular composition. Because of compositional fluctuations and active processes, it is challenging to measure it in intact cells. Here, we study the plasma membrane using giant plasma membrane vesicles (GPMVs), which largely preserve the plasma membrane lipidome and proteome. We show that the bending rigidity of plasma membranes under varied conditions is correlated to readout from environment-sensitive dyes, which are indicative of membrane order and microviscosity. This correlation holds across different cell lines, upon cholesterol depletion or enrichment of the plasma membrane, and variations in cell density. Thus, polarity- and viscosity-sensitive probes represent a promising indicator of membrane mechanical properties. Additionally, our results allow for identifying synthetic membranes with a few well defined lipids as optimal plasma membrane mimetics.
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Affiliation(s)
- Jan Steinkühler
- Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
| | - Erdinc Sezgin
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, Oxford, OX3 9DS UK
| | - Iztok Urbančič
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, Oxford, OX3 9DS UK
- Condensed Matter Physics Department, “Jožef Stefan” Institute, Ljubljana, Slovenia
| | - Christian Eggeling
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, Oxford, OX3 9DS UK
- Institute of Applied Optics Friedrich‐Schiller‐University Jena, Max-Wien Platz 4, 07743 Jena, Germany
- Leibniz Institute of Photonic Technology e.V., Albert-Einstein-Straße 9, 07745 Jena, Germany
| | - Rumiana Dimova
- Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
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91
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Ashoka AH, Ashokkumar P, Kovtun YP, Klymchenko AS. Solvatochromic Near-Infrared Probe for Polarity Mapping of Biomembranes and Lipid Droplets in Cells under Stress. J Phys Chem Lett 2019; 10:2414-2421. [PMID: 31021640 DOI: 10.1021/acs.jpclett.9b00668] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Can polarity-sensitive fluorescent dyes monitor the response of live cells to fundamental stress conditions, such as deprivation from nutrition and oxidative stress? To address this question, we developed a push-pull dioxaborine probe (DXB-NIR) for biomembranes and lipid droplets featuring strong solvatochromism in the far-red to near-infrared region, high fluorescence brightness, photostability, and two-photon absorption cross section, reaching 13800 GM at 930 nm. In model membranes, DXB-NIR exhibits unprecedented 80 nm shift between liquid ordered and disordered membrane phases, allowing robust imaging of separated membrane microdomains. Two-color imaging of live cells with DXB-NIR enables polarity mapping in plasma membranes, endoplasmic reticulum, and lipid droplets, which reveals that starvation and oxidative stress produce an increase in the local polarity, and this change is different for each of the studied cell compartments. Thus, by pushing the limits of existing solvatochromic dyes, we introduce a concept of polarity mapping for monitoring the response of cells to stress.
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Affiliation(s)
- Anila Hoskere Ashoka
- Laboratoire de Bioimagerie et Pathologies , UMR 7021 CNRS, Faculté de Pharmacie, Université de Strasbourg , Strasbourg , CS 60024 , France
| | - Pichandi Ashokkumar
- Laboratoire de Bioimagerie et Pathologies , UMR 7021 CNRS, Faculté de Pharmacie, Université de Strasbourg , Strasbourg , CS 60024 , France
| | - Yuriy P Kovtun
- Institute of Organic Chemistry , National Academy of Sciences of Ukraine , 5 Murmanska Street , 02094 Kyiv , Ukraine
| | - Andrey S Klymchenko
- Laboratoire de Bioimagerie et Pathologies , UMR 7021 CNRS, Faculté de Pharmacie, Université de Strasbourg , Strasbourg , CS 60024 , France
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92
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Ruiz M, Ståhlman M, Borén J, Pilon M. AdipoR1 and AdipoR2 maintain membrane fluidity in most human cell types and independently of adiponectin. J Lipid Res 2019; 60:995-1004. [PMID: 30890562 PMCID: PMC6495173 DOI: 10.1194/jlr.m092494] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 03/07/2019] [Indexed: 12/16/2022] Open
Abstract
The FA composition of phospholipids must be tightly regulated to maintain optimal cell membrane properties and compensate for a highly variable supply of dietary FAs. Previous studies have shown that AdipoR2 and its homologue PAQR-2 are important regulators of phospholipid FA composition in HEK293 cells and Caenorhabditiselegans, respectively. Here we show that both AdipoR1 and AdipoR2 are essential for sustaining desaturase expression and high levels of unsaturated FAs in membrane phospholipids of many human cell types, including primary human umbilical vein endothelial cells, and for preventing membrane rigidification in cells challenged with exogenous palmitate, a saturated FA. Three independent methods confirm the role of the AdipoRs as regulators of membrane composition and fluidity: fluorescence recovery after photobleaching, measurements of Laurdan dye generalized polarization, and mass spectrometry to determine the FA composition of phospholipids. Furthermore, we show that the AdipoRs can prevent lipotoxicity in the complete absence of adiponectin, their putative ligand. We propose that the primary cellular function of AdipoR1 and AdipoR2 is to maintain membrane fluidity in most human cell types and that adiponectin is not required for this function.
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Affiliation(s)
- Mario Ruiz
- Department of Chemistry and Molecular Biology; University of Gothenburg, Gothenburg, Sweden
| | - Marcus Ståhlman
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Jan Borén
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Marc Pilon
- Department of Chemistry and Molecular Biology; University of Gothenburg, Gothenburg, Sweden.
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93
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Effects of oxidation on the physicochemical properties of polyunsaturated lipid membranes. J Colloid Interface Sci 2019; 538:404-419. [DOI: 10.1016/j.jcis.2018.12.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 11/29/2018] [Accepted: 12/02/2018] [Indexed: 12/13/2022]
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94
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Abstract
Mitochondria undergo frequent fusion and fission events to adapt their morphology to cellular needs. Homotypic docking and fusion of outer mitochondrial membranes are controlled by Mitofusins, a set of large membrane-anchored GTPase proteins belonging to the dynamin superfamily. Mitofusins include, in addition to their GTPase and transmembrane domains, two heptad repeat domains, HR1 and HR2. All four regions are crucial for Mitofusin function, but their precise contribution to mitochondrial docking and fusion events has remained elusive until very recently. In this commentary, we first give an overview of the established strategies employed by various protein machineries distinct from Mitofusins to mediate membrane fusion. We then present recent structure–function data on Mitofusins that provide important novel insights into their mode of action in mitochondrial fusion.
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Affiliation(s)
- Mickael M Cohen
- Sorbonne Université, CNRS UMR8226, Institut de Biologie Physico-Chimique, Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, Paris, France
| | - David Tareste
- Université Paris Descartes, Sorbonne Paris Cité, INSERM ERL U950, Trafic Membranaire dans le Cerveau Normal et Pathologique, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, INSERM UMR 894, Institut de Psychiatrie et Neurosciences de Paris, Paris, France
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95
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Ruiz M, Bodhicharla R, Svensk E, Devkota R, Busayavalasa K, Palmgren H, Ståhlman M, Boren J, Pilon M. Membrane fluidity is regulated by the C. elegans transmembrane protein FLD-1 and its human homologs TLCD1/2. eLife 2018; 7:e40686. [PMID: 30509349 PMCID: PMC6279351 DOI: 10.7554/elife.40686] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 11/04/2018] [Indexed: 12/15/2022] Open
Abstract
Dietary fatty acids are the main building blocks for cell membranes in animals, and mechanisms must therefore exist that compensate for dietary variations. We isolated C. elegans mutants that improved tolerance to dietary saturated fat in a sensitized genetic background, including eight alleles of the novel gene fld-1 that encodes a homolog of the human TLCD1 and TLCD2 transmembrane proteins. FLD-1 is localized on plasma membranes and acts by limiting the levels of highly membrane-fluidizing long-chain polyunsaturated fatty acid-containing phospholipids. Human TLCD1/2 also regulate membrane fluidity by limiting the levels of polyunsaturated fatty acid-containing membrane phospholipids. FLD-1 and TLCD1/2 do not regulate the synthesis of long-chain polyunsaturated fatty acids but rather limit their incorporation into phospholipids. We conclude that inhibition of FLD-1 or TLCD1/2 prevents lipotoxicity by allowing increased levels of membrane phospholipids that contain fluidizing long-chain polyunsaturated fatty acids. Editorial note This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).
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Affiliation(s)
- Mario Ruiz
- Department of Chemistry and Molecular BiologyUniversity of GothenburgGothenburgSweden
| | - Rakesh Bodhicharla
- Department of Chemistry and Molecular BiologyUniversity of GothenburgGothenburgSweden
| | - Emma Svensk
- Department of Chemistry and Molecular BiologyUniversity of GothenburgGothenburgSweden
| | - Ranjan Devkota
- Department of Chemistry and Molecular BiologyUniversity of GothenburgGothenburgSweden
| | - Kiran Busayavalasa
- Department of Chemistry and Molecular BiologyUniversity of GothenburgGothenburgSweden
| | - Henrik Palmgren
- Department of Chemistry and Molecular BiologyUniversity of GothenburgGothenburgSweden
- Diabetes Bioscience, Cardiovascular, Renal and Metabolism, IMED Biotech UnitAstraZenecaGothenburgSweden
| | - Marcus Ståhlman
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of MedicineUniversity of GothenburgGothenburgSweden
| | - Jan Boren
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of MedicineUniversity of GothenburgGothenburgSweden
| | - Marc Pilon
- Department of Chemistry and Molecular BiologyUniversity of GothenburgGothenburgSweden
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Manni MM, Sot J, Arretxe E, Gil-Redondo R, Falcón-Pérez JM, Balgoma D, Alonso C, Goñi FM, Alonso A. The fatty acids of sphingomyelins and ceramides in mammalian tissues and cultured cells: Biophysical and physiological implications. Chem Phys Lipids 2018; 217:29-34. [PMID: 30359584 DOI: 10.1016/j.chemphyslip.2018.09.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 09/18/2018] [Indexed: 02/07/2023]
Abstract
Sphingolipids consist of a sphingoid base N-linked to a fatty acyl chain. Among them, sphingomyelins (SM) are major components of mammalian cells, while ceramide (Cer) plays an important role as a lipid second messenger. We have performed a quantitative lipidomic study of Cer and SM species in different mammalian tissues (adipose tissue, liver, brain and blood serum of human, mice, rat and dog), as well as in cell cultures of mammalian origin (primary hepatocytes, immortalized MDCK cells, mice melanoma b16 cells, and mice primary CD4 + T lymphocytes) using an ultra-high performance liquid chromatography coupled to time-of-flight mass spectrometry (UHPLC-ToF-MS)-based platform. The data have been compared with published, in general semi-quantitative, results from 20 other samples, with good agreement. The sphingoid base was predominantly d18-1 sphingosine (2-amino-4-octadecene-1,3-diol) in all cases. The fatty acid composition of SM was clearly different from that of Cer. In virtually all samples the most abundant Cer species were those containing C24:0 and C24:1 in their N-acyl chains, while the main species contained in SM was C16:0. Brain was the most divergent tissue, in which Cer and SM C18:0 were very abundant.
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Affiliation(s)
- Marco M Manni
- Instituto Biofisika (CSIC, UPV/EHU), Campus Universitario, 48940 Leioa, Spain; Departamento de Bioquímica, Universidad del País Vasco, B. Sarriena s/n, 48940 Leioa, Spain
| | - Jesús Sot
- Instituto Biofisika (CSIC, UPV/EHU), Campus Universitario, 48940 Leioa, Spain; Departamento de Bioquímica, Universidad del País Vasco, B. Sarriena s/n, 48940 Leioa, Spain
| | - Enara Arretxe
- OWL Metabolomics, Parque Tecnológico de Bizkaia, 48160, Derio, Spain
| | - Rubén Gil-Redondo
- CIC bioGUNE, CIBERehd, Parque Tecnológico de Bizkaia, 48160, Derio, Spain
| | - Juan M Falcón-Pérez
- CIC bioGUNE, CIBERehd, Parque Tecnológico de Bizkaia, 48160, Derio, Spain; IKERBASQUE, Basque Foundation for Science, 48013, Bilbao, Spain
| | - David Balgoma
- OWL Metabolomics, Parque Tecnológico de Bizkaia, 48160, Derio, Spain
| | - Cristina Alonso
- OWL Metabolomics, Parque Tecnológico de Bizkaia, 48160, Derio, Spain
| | - Félix M Goñi
- Instituto Biofisika (CSIC, UPV/EHU), Campus Universitario, 48940 Leioa, Spain; Departamento de Bioquímica, Universidad del País Vasco, B. Sarriena s/n, 48940 Leioa, Spain
| | - Alicia Alonso
- Instituto Biofisika (CSIC, UPV/EHU), Campus Universitario, 48940 Leioa, Spain; Departamento de Bioquímica, Universidad del País Vasco, B. Sarriena s/n, 48940 Leioa, Spain.
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