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Mak KM, Shekhar AC. Soybean polyenylphosphatidylcholine (PPC) is beneficial in liver and extrahepatic tissue injury: An update in experimental research. Anat Rec (Hoboken) 2024; 307:2162-2186. [PMID: 37814787 DOI: 10.1002/ar.25333] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 08/11/2023] [Accepted: 09/18/2023] [Indexed: 10/11/2023]
Abstract
Polyenylphosphatidylcholine (PPC) is a purified polyunsaturated phosphatidylcholine extract of soybeans. This article updates PPC's beneficial effects on various forms of liver cell injury and other tissues in experimental research. PPC downregulates hepatocyte CYP2E1 expression and associated hepatotoxicity, as well as attenuates oxidative stress, apoptosis, lipoprotein oxidation and steatosis in alcoholic and nonalcoholic liver injury. PPC inhibits pro-inflammatory cytokine production, while stimulating anti-inflammatory cytokine secretion in ethanol or lipopolysaccharide-stimulated Kupffer cells/macrophages. It promotes M2-type macrophage polarization and metabolic reprogramming of glucose and lipid metabolism. PPC mitigates steatosis in NAFLD through inhibiting polarization of pro-inflammatory M1-type Kupffer cells, alleviating metabolic inflammation, remodeling hepatic lipid metabolism, correcting imbalances between lipogenesis and lipolysis and enhancing lipoprotein secretion from hepatocytes. PPC is antifibrotic by preventing progression of alcoholic hepatic fibrosis in baboons and also prevents CCl4-induced fibrosis in rats. PPC supplementation replenishes the phosphatidylcholine content of damaged cell membranes, resulting in increased membrane fluidity and functioning. Phosphatidylcholine repletion prevents increased membrane curvature of the endoplasmic reticulum and Golgi and decreases sterol regulatory element binding protein-1-mediated lipogenesis, reducing steatosis. PPC remodels gut microbiota and affects hepatic lipid metabolism via the gut-hepatic-axis and also alleviates brain inflammatory responses and cognitive impairment via the gut-brain-axis. Additionally, PPC protects extrahepatic tissues from injury caused by various toxic compounds by reducing oxidative stress, inflammation, and membrane damage. It also stimulates liver regeneration, enhances sensitivity of cancer cells to radiotherapy/chemotherapy, and inhibits experimental hepatocarcinogenesis. PPC's beneficial effects justify it as a supportive treatment of liver disease.
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Affiliation(s)
- Ki M Mak
- Department of Medical Education and Center for Anatomy and Functional Morphology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Aditya C Shekhar
- Department of Medical Education and Center for Anatomy and Functional Morphology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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2
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Das K, Nozaki T. Non-Vesicular Lipid Transport Machinery in Leishmania donovani: Functional Implications in Host-Parasite Interaction. Int J Mol Sci 2023; 24:10637. [PMID: 37445815 DOI: 10.3390/ijms241310637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 05/21/2023] [Accepted: 05/22/2023] [Indexed: 07/15/2023] Open
Abstract
Eukaryotic cells have distinct membrane-enclosed organelles, each with a unique biochemical signature and specialized function. The unique identity of each organelle is greatly governed by the asymmetric distribution and regulated intracellular movement of two important biomolecules, lipids, and proteins. Non-vesicular lipid transport mediated by lipid-transfer proteins (LTPs) plays essential roles in intra-cellular lipid trafficking and cellular lipid homeostasis, while vesicular transport regulates protein trafficking. A comparative analysis of non-vesicular lipid transport machinery in protists could enhance our understanding of parasitism and basis of eukaryotic evolution. Leishmania donovani, the trypanosomatid parasite, greatly depends on receptor-ligand mediated signalling pathways for cellular differentiation, nutrient uptake, secretion of virulence factors, and pathogenesis. Lipids, despite being important signalling molecules, have intracellular transport mechanisms that are largely unexplored in L. donovani. We have identified a repertoire of sixteen (16) potential lipid transfer protein (LTP) homologs based on a domain-based search on TriTrypDB coupled with bioinformatics analyses, which signifies the presence of well-organized lipid transport machinery in this parasite. We emphasized here their evolutionary uniqueness and conservation and discussed their potential implications for parasite biology with regards to future therapeutic targets against visceral leishmaniasis.
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Affiliation(s)
- Koushik Das
- Department of Allied Health Sciences, School of Health Sciences and Technology, University of Petroleum and Energy Studies, Dehradun 248007, India
| | - Tomoyoshi Nozaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
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3
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Perez-Salas U, Garg S, Gerelli Y, Porcar L. Deciphering lipid transfer between and within membranes with time-resolved small-angle neutron scattering. CURRENT TOPICS IN MEMBRANES 2021; 88:359-412. [PMID: 34862031 DOI: 10.1016/bs.ctm.2021.10.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This review focuses on time-resolved neutron scattering, particularly time-resolved small angle neutron scattering (TR-SANS), as a powerful in situ noninvasive technique to investigate intra- and intermembrane transport and distribution of lipids and sterols in lipid membranes. In contrast to using molecular analogues with potentially large chemical tags that can significantly alter transport properties, small angle neutron scattering relies on the relative amounts of the two most abundant isotope forms of hydrogen: protium and deuterium to detect complex membrane architectures and transport processes unambiguously. This review discusses advances in our understanding of the mechanisms that sustain lipid asymmetry in membranes-a key feature of the plasma membrane of cells-as well as the transport of lipids between membranes, which is an essential metabolic process.
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Affiliation(s)
- Ursula Perez-Salas
- Physics Department, University of Illinois at Chicago, Chicago, IL, United States.
| | - Sumit Garg
- Physics Department, University of Illinois at Chicago, Chicago, IL, United States
| | - Yuri Gerelli
- Department of Life and Environmental Sciences, Universita` Politecnica delle Marche, Ancona, Italy
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Avula K, Singh B, Kumar PV, Syed GH. Role of Lipid Transfer Proteins (LTPs) in the Viral Life Cycle. Front Microbiol 2021; 12:673509. [PMID: 34248884 PMCID: PMC8260984 DOI: 10.3389/fmicb.2021.673509] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 05/17/2021] [Indexed: 12/14/2022] Open
Abstract
Viruses are obligate parasites that depend on the host cell machinery for their replication and dissemination. Cellular lipids play a central role in multiple stages of the viral life cycle such as entry, replication, morphogenesis, and egress. Most viruses reorganize the host cell membranes for the establishment of viral replication complex. These specialized structures allow the segregation of replicating viral RNA from ribosomes and protect it from host nucleases. They also facilitate localized enrichment of cellular components required for viral replication and assembly. The specific composition of the lipid membrane governs its ability to form negative or positive curvature and possess a rigid or flexible form, which is crucial for membrane rearrangement and establishment of viral replication complexes. In this review, we highlight how different viruses manipulate host lipid transfer proteins and harness their functions to enrich different membrane compartments with specific lipids in order to facilitate multiple aspects of the viral life cycle.
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Affiliation(s)
- Kiran Avula
- Virus-Host Interaction Lab, Institute of Life Sciences, Bhubaneshwar, India.,Regional Centre for Biotechnology, Faridabad, India
| | - Bharati Singh
- Virus-Host Interaction Lab, Institute of Life Sciences, Bhubaneshwar, India.,School of Biotechnology, Kalinga Institute of Industrial Technology, Bhubaneshwar, India
| | - Preethy V Kumar
- Virus-Host Interaction Lab, Institute of Life Sciences, Bhubaneshwar, India.,School of Biotechnology, Kalinga Institute of Industrial Technology, Bhubaneshwar, India
| | - Gulam H Syed
- Virus-Host Interaction Lab, Institute of Life Sciences, Bhubaneshwar, India
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5
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Liu Y, Kelley EG, Batchu KC, Porcar L, Perez-Salas U. Creating Asymmetric Phospholipid Vesicles via Exchange With Lipid-Coated Silica Nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:8865-8873. [PMID: 32623897 PMCID: PMC7899156 DOI: 10.1021/acs.langmuir.0c01188] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Recently, effort has been placed into fabricating model free-floating asymmetric lipid membranes, such as asymmetric vesicles. Here, we report on the use of lipid-coated silica nanoparticles to exchange lipids with initially symmetric vesicles to generate composition-controlled asymmetric vesicles. Our method relies on the simple and natural exchange of lipids between membranes through an aqueous medium. Using a selected temperature, time, and ratio of lipid-coated silica nanoparticles to vesicles, we produced a desired highly asymmetric leaflet composition. At this point, the silica nanoparticles were removed by centrifugation, leaving the asymmetric vesicles in solution. In the present work, the asymmetric vesicles were composed of isotopically distinct dipalmitoylphosphatidylcholine lipids. Lipid asymmetry was detected by both small-angle neutron scattering (SANS) and proton nuclear magnetic resonance (1H NMR). The rate at which the membrane homogenizes at 75 °C was also assessed.
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Affiliation(s)
- Yangmingyue Liu
- Physics Department, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Elizabeth G Kelley
- NIST Center For Neutron Research, Gaithersburg, Maryland 20889, United States
| | - Krishna C Batchu
- Large Scale Structure Group, Institut Laue-Langevin, Grenoble F-38042, France
| | - Lionel Porcar
- Large Scale Structure Group, Institut Laue-Langevin, Grenoble F-38042, France
| | - Ursula Perez-Salas
- Physics Department, University of Illinois at Chicago, Chicago, Illinois 60607, United States
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6
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Das K, Nozaki T. Non-vesicular Lipid Transport Machinery in Entamoeba histolytica. Front Cell Infect Microbiol 2018; 8:315. [PMID: 30283742 PMCID: PMC6156432 DOI: 10.3389/fcimb.2018.00315] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 08/20/2018] [Indexed: 12/18/2022] Open
Abstract
Eukaryotic cells are organized into separate membrane-bound compartments that have specialized biochemical signature and function. Maintenance and regulation of distinct identity of each compartment is governed by the uneven distribution and intra-cellular movement of two essential biomolecules, lipids, and proteins. Non-vesicular lipid transport mediated by lipid transfer proteins plays a pivotal role in intra-cellular lipid trafficking and homeostasis whereas vesicular transport plays a central role in protein trafficking. Comparative study of lipid transport machinery in protist helps to better understand the pathogenesis and parasitism, and provides insight into eukaryotic evolution. Amebiasis, which is caused by Entamoeba histolytica, is one of the major enteric infections in humans, resulting in 40–100 thousand deaths annually. This protist has undergone remarkable alterations in the content and function of its sub-cellular compartments as well represented by its unique diversification of mitochondrion-related organelle, mitosome. We conducted domain-based search on AmoebaDB coupled with bioinformatics analyses and identified 22 potential lipid transfer protein homologs in E. histolytica, which are grouped into several sub-classes. Such in silico analyses have demonstrated the existence of well-organized lipid transport machinery in this parasite. We summarized and discussed the conservation and unique features of the whole repertoire of lipid transport proteins in E. histolytica.
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Affiliation(s)
- Koushik Das
- Graduate School of Medicine, The University of Tokyo, Bunkyō, Japan
| | - Tomoyoshi Nozaki
- Graduate School of Medicine, The University of Tokyo, Bunkyō, Japan
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7
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Wah B, Breidigan JM, Adams J, Horbal P, Garg S, Porcar L, Perez-Salas U. Reconciling Differences between Lipid Transfer in Free-Standing and Solid Supported Membranes: A Time-Resolved Small-Angle Neutron Scattering Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:3384-3394. [PMID: 28300412 DOI: 10.1021/acs.langmuir.6b04013] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Maintaining compositional lipid gradients across membranes in animal cells is essential to biological function, but what is the energetic cost to maintain these differences? It has long been recognized that studying the passive movement of lipids in membranes can provide insight into this toll. Confusingly the reported values of inter- and, particularly, intra-lipid transport rates of lipids in membranes show significant differences. To overcome this difficulty, biases introduced by experimental approaches have to be identified. The present study addresses the difference in the reported intramembrane transport rates of dimyristoylphosphatidylcholine (DMPC) on flat solid supports (fast flipping) and in curved free-standing membranes (slow flipping). Two possible scenarios are potentially at play: one is the difference in curvature of the membranes studied and the other the presence (or not) of the support. Using DMPC vesicles and DMPC supported membranes on silica nanoparticles of different radii, we found that an increase in curvature (from a diameter of 30 nm to a diameter of 100 nm) does not change the rates significantly, differing only by factors of order ∼1. Additionally, we found that the exchange rates of DMPC in supported membranes are similar to the ones in vesicles. And as previously reported, we found that the activation energies for exchange on free-standing and supported membranes are similar (84 and 78 kJ/mol, respectively). However, DMPC's flip-flop rates increase significantly when in a supported membrane, surpassing the exchange rates and no longer limiting the exchange process. Although the presence of holes or cracks in supported membranes explains the occurrence of fast lipid flip-flop in many studies, in defect-free supported membranes we find that fast flip-flop is driven by the surface's induced disorder of the bilayer's acyl chain packing as evidenced from their broad melting temperature behavior.
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Affiliation(s)
- Benny Wah
- Physics Department, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Jeffrey M Breidigan
- Physics Department, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Joseph Adams
- Physics Department, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Piotr Horbal
- Physics Department, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Sumit Garg
- Physics Department, University of Illinois at Chicago , Chicago, Illinois 60607, United States
- Materials Science Division, Argonne National Laboratory , Lemont, Illinois 60439, United States
| | - Lionel Porcar
- Large Scale Structure Group, Institut Laue-Langevin , Grenoble F-38042, France
- Department of Chemical Engineering, Colburn Laboratory, University of Delaware , Newark, Delaware 19716, United States
| | - Ursula Perez-Salas
- Physics Department, University of Illinois at Chicago , Chicago, Illinois 60607, United States
- Materials Science Division, Argonne National Laboratory , Lemont, Illinois 60439, United States
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8
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Lipid transfer proteins and the tuning of compartmental identity in the Golgi apparatus. Chem Phys Lipids 2016; 200:42-61. [DOI: 10.1016/j.chemphyslip.2016.06.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Revised: 06/21/2016] [Accepted: 06/22/2016] [Indexed: 11/23/2022]
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9
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Smulan LJ, Ding W, Freinkman E, Gujja S, Edwards YJK, Walker AK. Cholesterol-Independent SREBP-1 Maturation Is Linked to ARF1 Inactivation. Cell Rep 2016; 16:9-18. [PMID: 27320911 DOI: 10.1016/j.celrep.2016.05.086] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 04/29/2016] [Accepted: 05/22/2016] [Indexed: 11/19/2022] Open
Abstract
Lipogenesis requires coordinated expression of genes for fatty acid, phospholipid, and triglyceride synthesis. Transcription factors, such as SREBP-1 (Sterol regulatory element binding protein), may be activated in response to feedback mechanisms linking gene activation to levels of metabolites in the pathways. SREBPs can be regulated in response to membrane cholesterol and we also found that low levels of phosphatidylcholine (a methylated phospholipid) led to SBP-1/SREBP-1 maturation in C. elegans or mammalian models. To identify additional regulatory components, we performed a targeted RNAi screen in C. elegans, finding that both lpin-1/Lipin 1 (which converts phosphatidic acid to diacylglycerol) and arf-1.2/ARF1 (a GTPase regulating Golgi function) were important for low-PC activation of SBP-1/SREBP-1. Mechanistically linking the major hits of our screen, we find that limiting PC synthesis or LPIN1 knockdown in mammalian cells reduces the levels of active GTP-bound ARF1. Thus, changes in distinct lipid ratios may converge on ARF1 to increase SBP-1/SREBP-1 activity.
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Affiliation(s)
- Lorissa J Smulan
- Program in Molecular Medicine, UMASS Medical School, 373 Plantation Street, Worcester, MA 01605, USA
| | - Wei Ding
- Program in Molecular Medicine, UMASS Medical School, 373 Plantation Street, Worcester, MA 01605, USA
| | - Elizaveta Freinkman
- Metabolite Profiling Facility, Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - Sharvari Gujja
- Program in Molecular Medicine, UMASS Medical School, 373 Plantation Street, Worcester, MA 01605, USA
| | - Yvonne J K Edwards
- Program in Molecular Medicine, UMASS Medical School, 373 Plantation Street, Worcester, MA 01605, USA
| | - Amy K Walker
- Program in Molecular Medicine, UMASS Medical School, 373 Plantation Street, Worcester, MA 01605, USA.
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10
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Kamerbeek CB, Mateos MV, Vallés AS, Pediconi MF, Barrantes FJ, Borroni V. Diacylglycerol levels modulate the cellular distribution of the nicotinic acetylcholine receptor. Int J Biochem Cell Biol 2016; 74:1-11. [PMID: 26898898 DOI: 10.1016/j.biocel.2016.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2015] [Revised: 02/03/2016] [Accepted: 02/15/2016] [Indexed: 10/22/2022]
Abstract
Diacylglycerol (DAG), a second messenger involved in different cell signaling cascades, activates protein kinase C (PKC) and D (PKD), among other kinases. The present work analyzes the effects resulting from the alteration of DAG levels on neuronal and muscle nicotinic acetylcholine receptor (AChR) distribution. We employ CHO-K1/A5 cells, expressing adult muscle-type AChR in a stable manner, and hippocampal neurons, which endogenously express various subtypes of neuronal AChR. CHO-K1/A5 cells treated with dioctanoylglycerol (DOG) for different periods showed augmented AChR cell surface levels at short incubation times (30min-4h) whereas at longer times (18h) the AChR was shifted to intracellular compartments. Similarly, in cultured hippocampal neurons surface AChR levels increased as a result of DOG incubation for 4h. Inhibition of endogenous DAG catabolism produced changes in AChR distribution similar to those induced by DOG treatment. Specific enzyme inhibitors and Western blot assays revealed that DAGs exert their effect on AChR distribution through the modulation of the activity of classical PKC (cPKC), novel PKC (nPKC) and PKD activity.
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Affiliation(s)
- Constanza B Kamerbeek
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Camino La Carrindanga km 7, 8000 Bahía Blanca, Argentina
| | - Melina V Mateos
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Camino La Carrindanga km 7, 8000 Bahía Blanca, Argentina
| | - Ana S Vallés
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Camino La Carrindanga km 7, 8000 Bahía Blanca, Argentina
| | - María F Pediconi
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Camino La Carrindanga km 7, 8000 Bahía Blanca, Argentina
| | - Francisco J Barrantes
- Laboratory of Molecular Neurobiology, Institute for Biomedical Research UCA-CONICET, Faculty of Medical Sciences, Av. Alicia Moreau de Justo 1600, C1107AFF Buenos Aires, Argentina
| | - Virginia Borroni
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Camino La Carrindanga km 7, 8000 Bahía Blanca, Argentina.
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11
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Weber P, Hornjik M, Olayioye MA, Hausser A, Radde NE. A computational model of PKD and CERT interactions at the trans-Golgi network of mammalian cells. BMC SYSTEMS BIOLOGY 2015; 9:9. [PMID: 25889812 PMCID: PMC4349302 DOI: 10.1186/s12918-015-0147-1] [Citation(s) in RCA: 179] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 01/26/2015] [Indexed: 11/10/2022]
Abstract
BACKGROUND In mammalian cells protein-lipid interactions at the trans-Golgi network (TGN) determine the formation of vesicles, which transfer secretory proteins to the cellular membrane. This process is regulated by a complex molecular network including protein kinase D (PKD), which is directly involved in the fission of transport vesicles, and its interaction with the ceramide transfer protein CERT that transports ceramide from the endoplasmic reticulum to the TGN. RESULTS Here we present a novel quantitative kinetic model for the interactions of the key players PKD, phosphatidylinositol 4-kinase III beta (PI4KIII β) and CERT at the TGN membranes. We use sampling-based Bayesian analysis and perturbation experiments for model calibration and validation. CONCLUSIONS Our quantitative predictions of absolute molecular concentrations and reaction fluxes have major biological implications: Model comparison provides evidence that PKD and CERT interact in a cooperative manner to regulate ceramide transfer. Furthermore, we identify active PKD to be the dominant regulator of the network, especially of CERT-mediated ceramide transfer.
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Affiliation(s)
- Patrick Weber
- Institute for Systems Theory and Automatic Control, University of Stuttgart, Pfaffenwaldring 9, Stuttgart, 70569, Germany.
| | - Mariana Hornjik
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, 70569, Germany.
| | - Monilola A Olayioye
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, 70569, Germany.
| | - Angelika Hausser
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, 70569, Germany.
| | - Nicole E Radde
- Institute for Systems Theory and Automatic Control, University of Stuttgart, Pfaffenwaldring 9, Stuttgart, 70569, Germany.
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12
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Gutiérrez-Martínez E, Fernández-Ulibarri I, Lázaro-Diéguez F, Johannes L, Pyne S, Sarri E, Egea G. Lipid phosphate phosphatase 3 participates in transport carrier formation and protein trafficking in the early secretory pathway. J Cell Sci 2013; 126:2641-55. [PMID: 23591818 DOI: 10.1242/jcs.117705] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The inhibition of phosphatidic acid phosphatase (PAP) activity by propanolol indicates that diacylglycerol (DAG) is required for the formation of transport carriers at the Golgi and for retrograde trafficking to the ER. Here we report that the PAP2 family member lipid phosphate phosphatase 3 (LPP3, also known as PAP2b) localizes in compartments of the secretory pathway from ER export sites to the Golgi complex. The depletion of human LPP3: (i) reduces the number of tubules generated from the ER-Golgi intermediate compartment and the Golgi, with those formed from the Golgi being longer in LPP3-silenced cells than in control cells; (ii) impairs the Rab6-dependent retrograde transport of Shiga toxin subunit B from the Golgi to the ER, but not the anterograde transport of VSV-G or ssDsRed; and (iii) induces a high accumulation of Golgi-associated membrane buds. LPP3 depletion also reduces levels of de novo synthesized DAG and the Golgi-associated DAG contents. Remarkably, overexpression of a catalytically inactive form of LPP3 mimics the effects of LPP3 knockdown on Rab6-dependent retrograde transport. We conclude that LPP3 participates in the formation of retrograde transport carriers at the ER-Golgi interface, where it transitorily cycles, and during its route to the plasma membrane.
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Affiliation(s)
- Enric Gutiérrez-Martínez
- Departament de Biologia Cel·lular, Immunologia i Neurociències, Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
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13
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Phosphatidylcholine and the CDP-choline cycle. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1831:523-32. [PMID: 23010477 DOI: 10.1016/j.bbalip.2012.09.009] [Citation(s) in RCA: 177] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 09/16/2012] [Indexed: 11/20/2022]
Abstract
The CDP-choline pathway of phosphatidylcholine (PtdCho) biosynthesis was first described more than 50 years ago. Investigation of the CDP-choline pathway in yeast provides a basis for understanding the CDP-choline pathway in mammals. PtdCho is considered as an intermediate in a cycle of synthesis and degradation, and the activity of a CDP-choline cycle is linked to subcellular membrane lipid movement. The components of the mammalian CDP-choline pathway include choline transport, choline kinase, phosphocholine cytidylyltransferase, and choline phosphotransferase activities. The protein isoforms and biochemical mechanisms of regulation of the pathway enzymes are related to their cell- and tissue-specific functions. Regulated PtdCho turnover mediated by phospholipases or neuropathy target esterase participates in the mammalian CDP-choline cycle. Knockout mouse models define the biological functions of the CDP-choline cycle in mammalian cells and tissues. This article is part of a Special Issue entitled Phospholipids and Phospholipid Metabolism.
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14
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Walker AK, Jacobs RL, Watts JL, Rottiers V, Jiang K, Finnegan DM, Shioda T, Hansen M, Yang F, Niebergall LJ, Vance DE, Tzoneva M, Hart AC, Näär AM. A conserved SREBP-1/phosphatidylcholine feedback circuit regulates lipogenesis in metazoans. Cell 2011; 147:840-52. [PMID: 22035958 DOI: 10.1016/j.cell.2011.09.045] [Citation(s) in RCA: 321] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 06/14/2011] [Accepted: 09/19/2011] [Indexed: 12/17/2022]
Abstract
Sterol regulatory element-binding proteins (SREBPs) activate genes involved in the synthesis and trafficking of cholesterol and other lipids and are critical for maintaining lipid homeostasis. Aberrant SREBP activity, however, can contribute to obesity, fatty liver disease, and insulin resistance, hallmarks of metabolic syndrome. Our studies identify a conserved regulatory circuit in which SREBP-1 controls genes in the one-carbon cycle, which produces the methyl donor S-adenosylmethionine (SAMe). Methylation is critical for the synthesis of phosphatidylcholine (PC), a major membrane component, and we find that blocking SAMe or PC synthesis in C. elegans, mouse liver, and human cells causes elevated SREBP-1-dependent transcription and lipid droplet accumulation. Distinct from negative regulation of SREBP-2 by cholesterol, our data suggest a feedback mechanism whereby maturation of nuclear, transcriptionally active SREBP-1 is controlled by levels of PC. Thus, nutritional or genetic conditions limiting SAMe or PC production may activate SREBP-1, contributing to human metabolic disorders.
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Affiliation(s)
- Amy K Walker
- Massachusetts General Hospital Cancer Center, Building 149, 13th Street, Charlestown, MA 02129, USA.
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15
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Freeze HH, Ng BG. Golgi glycosylation and human inherited diseases. Cold Spring Harb Perspect Biol 2011; 3:a005371. [PMID: 21709180 DOI: 10.1101/cshperspect.a005371] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The Golgi factory receives custom glycosylates and dispatches its cargo to the correct cellular locations. The process requires importing donor substrates, moving the cargo, and recycling machinery. Correctly glycosylated cargo reflects the Golgi's quality and efficiency. Genetic disorders in the specific equipment (enzymes), donors (nucleotide sugar transporters), or equipment recycling/reorganization components (COG, SEC, golgins) can all affect glycosylation. Dozens of human glycosylation disorders fit these categories. Many other genes, with or without familiar names, well-annotated pedigrees, or likely homologies will join the ranks of glycosylation disorders. Their broad and unpredictable case-by-case phenotypes cross the traditional medical specialty boundaries. The gene functions in patients may be elusive, but their common feature may include altered glycosylation that provide clues to Golgi function. This article focuses on a group of human disorders that affect protein or lipid glycosylation. Readers may find it useful to generalize some of these patient-based, translational observations to their own research.
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Affiliation(s)
- Hudson H Freeze
- Genetic Disease Program, Sanford Children's Health Research Center, Sanford-Burnham Medical Research Institute, La Jolla, California 92037, USA.
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16
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Melser S, Molino D, Batailler B, Peypelut M, Laloi M, Wattelet-Boyer V, Bellec Y, Faure JD, Moreau P. Links between lipid homeostasis, organelle morphodynamics and protein trafficking in eukaryotic and plant secretory pathways. PLANT CELL REPORTS 2011; 30:177-193. [PMID: 21120657 DOI: 10.1007/s00299-010-0954-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Accepted: 11/15/2010] [Indexed: 05/30/2023]
Abstract
The role of lipids as molecular actors of protein transport and organelle morphology in plant cells has progressed over the last years through pharmacological and genetic investigations. The manuscript is reviewing the roles of various lipid families in membrane dynamics and trafficking in eukaryotic cells, and summarizes some of the related physicochemical properties of the lipids involved. The article also focuses on the specific requirements of the sphingolipid glucosylceramide (GlcCer) in Golgi morphology and protein transport through the plant secretory pathway. The use of a specific inhibitor of plant glucosylceramide synthase and selected Arabidopsis thaliana RNAi lines stably expressing several markers of the plant secretory pathway, establishes specific steps sensitive to GlcCer biosynthesis. Collectively, data of the literature demonstrate the existence of links between protein trafficking, organelle morphology, and lipid metabolism/homeostasis in eukaryotic cells including plant cells.
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Affiliation(s)
- Su Melser
- Laboratoire de Biogenèse Membranaire, UMR 5200 Université Bordeaux 2-CNRS, Université Bordeaux 2, case 92, 146 rue Léo-Saignat, 33076 Bordeaux, France.
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17
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Abstract
The movement of lipids within and between intracellular membranes is mediated by different lipid transport mechanisms and is crucial for maintaining the identities of different cellular organelles. Non-vesicular lipid transport has a crucial role in intracellular lipid trafficking and distribution, but its underlying mechanisms remain unclear. Lipid-transfer proteins (LTPs), which regulate diverse lipid-mediated cellular processes and accelerate vectorial transport of lipid monomers between membranes in vitro, could potentially mediate non-vesicular intracellular lipid trafficking. Understanding the mechanisms by which lipids are transported and distributed between cellular membranes, and elucidating the role of LTPs in intracellular lipid transport and homeostasis, are currently subjects of intensive study.
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18
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Beck R, Ravet M, Wieland F, Cassel D. The COPI system: Molecular mechanisms and function. FEBS Lett 2009; 583:2701-9. [DOI: 10.1016/j.febslet.2009.07.032] [Citation(s) in RCA: 214] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 07/07/2009] [Accepted: 07/13/2009] [Indexed: 02/03/2023]
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19
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Furt F, Moreau P. Importance of lipid metabolism for intracellular and mitochondrial membrane fusion/fission processes. Int J Biochem Cell Biol 2009; 41:1828-36. [PMID: 19703652 DOI: 10.1016/j.biocel.2009.02.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2008] [Revised: 02/06/2009] [Accepted: 02/10/2009] [Indexed: 10/21/2022]
Abstract
Mitochondria move along cytoskeletal tracks, fuse and divide. These dynamic features have been shown to be critical for several mitochondrial functions in cell viability and cell death. After a rapid recall of the proteic machineries that are known to be involved, the review will focus on lipids, other key molecular actors of membrane dynamics. A summary of the current knowledge on lipids and their implication in various cellular membrane fusion/fission processes will be first presented. The review will then report what has been discovered or can be expected on the role of the different families of lipids in mitochondrial membrane fusion and fission processes.
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Affiliation(s)
- Fabienne Furt
- Membrane Biogenesis Laboratory, UMR 5200, University of Bordeaux II-CNRS, France
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20
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Fagone P, Jackowski S. Membrane phospholipid synthesis and endoplasmic reticulum function. J Lipid Res 2008; 50 Suppl:S311-6. [PMID: 18952570 DOI: 10.1194/jlr.r800049-jlr200] [Citation(s) in RCA: 307] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
This review presents an overview of mammalian phospholipid synthesis and the cellular locations of the biochemical activities that produce membrane lipid molecular species. The generalized endoplasmic reticulum compartment is a central site for membrane lipid biogenesis, and examples of the emerging relationships between alterations in lipid composition, regulation of membrane lipid biogenesis, and cellular secretory function are discussed.
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Affiliation(s)
- Paolo Fagone
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
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21
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Tian Y, Pate C, Andreolotti A, Wang L, Tuomanen E, Boyd K, Claro E, Jackowski S. Cytokine secretion requires phosphatidylcholine synthesis. ACTA ACUST UNITED AC 2008; 181:945-57. [PMID: 18559668 PMCID: PMC2426940 DOI: 10.1083/jcb.200706152] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Choline cytidylyltransferase (CCT) is the rate-limiting enzyme in the phosphatidylcholine biosynthetic pathway. Here, we demonstrate that CCTα-mediated phosphatidylcholine synthesis is required to maintain normal Golgi structure and function as well as cytokine secretion from the Golgi complex. CCTα is localized to the trans-Golgi region and its expression is increased in lipopolysaccharide (LPS)-stimulated wild-type macrophages. Although LPS triggers transient reorganization of Golgi morphology in wild-type macrophages, similar structural alterations persist in CCTα-deficient cells. Pro–tumor necrosis factor α and interleukin-6 remain lodged in the secretory compartment of CCTα-deficient macrophages after LPS stimulation. However, the lysosomal-mediated secretion pathways for interleukin-1β secretion and constitutive apolipoprotein E secretion are unaltered. Exogenous lysophosphatidylcholine restores LPS-stimulated secretion from CCTα-deficient cells, and elevated diacylglycerol levels alone do not impede secretion of pro–tumor necrosis factor α or interleukin-6. These results identify CCTα as a key component in membrane biogenesis during LPS-stimulated cytokine secretion from the Golgi complex.
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Affiliation(s)
- Yong Tian
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
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22
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Peretti D, Dahan N, Shimoni E, Hirschberg K, Lev S. Coordinated lipid transfer between the endoplasmic reticulum and the Golgi complex requires the VAP proteins and is essential for Golgi-mediated transport. Mol Biol Cell 2008; 19:3871-84. [PMID: 18614794 DOI: 10.1091/mbc.e08-05-0498] [Citation(s) in RCA: 259] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Lipid transport between intracellular organelles is mediated by vesicular and nonvesicular transport mechanisms and is critical for maintaining the identities of different cellular membranes. Nonvesicular lipid transport between the endoplasmic reticulum (ER) and the Golgi complex has been proposed to affect the lipid composition of the Golgi membranes. Here, we show that the integral ER-membrane proteins VAP-A and VAP-B affect the structural and functional integrity of the Golgi complex. Depletion of VAPs by RNA interference reduces the levels of phosphatidylinositol-4-phosphate (PI4P), diacylglycerol, and sphingomyelin in the Golgi membranes, and it leads to substantial inhibition of Golgi-mediated transport events. These effects are coordinately mediated by the lipid-transfer/binding proteins Nir2, oxysterol-binding protein (OSBP), and ceramide-transfer protein (CERT), which interact with VAPs via their FFAT motif. The effect of VAPs on PI4P levels is mediated by the phosphatidylinositol/phosphatidylcholine transfer protein Nir2, which is required for Golgi targeting of OSBP and CERT and the subsequent production of diacylglycerol and sphingomyelin. We propose that Nir2, OSBP, and CERT function coordinately at the ER-Golgi membrane contact sites, thereby affecting the lipid composition of the Golgi membranes and consequently their structural and functional identities.
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Affiliation(s)
- Diego Peretti
- The Molecular Cell Biology Department, Weizmann Institute of Science, Rehovot 76100, Israel
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23
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Gandy S, Zhang YW, Ikin A, Schmidt SD, Bogush A, Levy E, Sheffield R, Nixon RA, Liao FF, Mathews PM, Xu H, Ehrlich ME. Alzheimer's presenilin 1 modulates sorting of APP and its carboxyl-terminal fragments in cerebral neurons in vivo. J Neurochem 2007; 102:619-26. [PMID: 17630980 DOI: 10.1111/j.1471-4159.2007.04587.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Studies in continuously cultured cells have established that familial Alzheimer's disease (FAD) mutant presenilin 1 (PS1) delays exit of the amyloid precursor protein (APP) from the trans-Golgi network (TGN). Here we report the first description of PS1-regulated APP trafficking in cerebral neurons in culture and in vivo. Using neurons from transgenic mice or a cell-free APP transport vesicle biogenesis system derived from the TGN of those neurons, we demonstrated that knocking-in an FAD-associated mutant PS1 transgene was associated with delayed kinetics of APP arrival at the cell surface. Apparently, this delay was at least partially attributable to impaired exit of APP from the TGN, which was documented in the cell-free APP transport vesicle biogenesis assay. To extend the study to APP and carboxyl terminal fragment (CTF) trafficking to cerebral neurons in vivo, we performed subcellular fractionation of brains from APP transgenic mice, some of which carried a second transgene encoding an FAD-associated mutant form of PS1. The presence of the FAD mutant PS1 was associated with a slight shift in the subcellular localization of both holoAPP and APP CTFs toward iodixanol density gradient fractions that were enriched in a marker for the TGN. In a parallel set of experiments, we used an APP : furin chimeric protein strategy to test the effect of artificially forcing TGN concentration of an APP : furin chimera that could be a substrate for beta- and gamma-cleavage. This chimeric substrate generated excess Abeta42 when compared with wildtype APP. These data indicate that the presence of an FAD-associated mutant human PS1 transgene is associated with redistribution of the APP and APP CTFs in brain neurons toward TGN-enriched fractions. The chimera experiment suggests that TGN-enrichment of a beta-/gamma-secretase substrate may play an integral role in the action of mutant PS1 to elevate brain levels of Abeta42.
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Affiliation(s)
- Sam Gandy
- Farber Institute for Neurosciences and the Department of Neurology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
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24
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Gómez-Fernández JC, Corbalán-García S. Diacylglycerols, multivalent membrane modulators. Chem Phys Lipids 2007; 148:1-25. [PMID: 17560968 DOI: 10.1016/j.chemphyslip.2007.04.003] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2007] [Accepted: 04/04/2007] [Indexed: 12/30/2022]
Abstract
Diacylglycerols are second messengers confined to biomembranes and, although relatively simple molecules from the structural point of view, they are able of triggering a surprisingly wide range of biological responses. Diacylglycerols are recognized by a well conserved protein motif, such as the C1 domain. This domain was observed for the first time in protein kinases C but is now known to be present in many other proteins. The effect of diacylglycerols is not limited to binding to C1 domains and they are able to alter the biophysical properties of biomembranes and hence modulate the activity of membrane associated proteins and also facilitate some processes like membrane fusion.
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Affiliation(s)
- Juan C Gómez-Fernández
- Departamento de Bioquímica y Biología Molecular (A), Facultad de Veterinaria, Universidad de Murcia, Apartado de Correos 4021, Murcia, Spain.
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25
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Trivedi D, Padinjat R. RdgB proteins: Functions in lipid homeostasis and signal transduction. Biochim Biophys Acta Mol Cell Biol Lipids 2007; 1771:692-9. [PMID: 17543578 DOI: 10.1016/j.bbalip.2007.04.014] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2006] [Revised: 04/26/2007] [Accepted: 04/26/2007] [Indexed: 11/22/2022]
Abstract
The RdgBs are a group of evolutionarily conserved molecules that contain a phosphatidylinositol transfer protein (PITP) domain. However in contrast to classical PITPs (PITPalpha) with whom they share the conserved PITP domain, these proteins also contain several additional sequence elements whose functional significance remains unknown. The founding member of the family DrdgB alpha (Drosophila rdgB) appears to be essential for sensory transduction and maintenance of ultra structure in photoreceptors (retinal sensory neurons). Although proposed to support the maintenance of phosphatidylinositol 4, 5 bisphosphate [PI (4, 5) P(2)] levels during G-protein coupled phospholipase C activity in these cells, the biochemical mechanism of DrdgB alpha function remains unresolved. More recently, a mammalian RdgB protein has been implicated in the maintenance of diacylglycerol (DAG) levels and secretory function at Golgi membranes. In this review we discuss existing work on the function of RdgB proteins and set out future challenges in understanding this group of lipid transfer proteins.
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Affiliation(s)
- Deepti Trivedi
- Inositide Laboratory, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
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26
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Moreau P. Lipids: architects and regulators of membrane dynamics and trafficking. PLANT SIGNALING & BEHAVIOR 2007; 2:157-159. [PMID: 19704742 PMCID: PMC2634043 DOI: 10.4161/psb.2.3.3686] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2006] [Accepted: 12/07/2006] [Indexed: 05/28/2023]
Abstract
We have recently shown that an inhibition of sterol synthesis by fenpropimorph leads to an accumulation of sterol precursors, hydroxypalmitic acid-containing glucosylceramides and detergent resistant membranes in the Golgi bodies instead of the plasma membrane, suggesting that the individual molecules or the microdomains were blocked in the Golgi. These results and others from several eukaryotic models link lipid metabolism with membrane morphodynamics that are involved in membrane trafficking. Focus has been expanded to other lipid families, and numerous evidences are given showing lipids and lipid-modifying enzymes as key regulators of membrane homeostasis which can strongly regulate membrane morphodynamics and therefore trafficking. Beside protein-based machineries, lipid-based machineries are also shown as crucial regulatory forces involved in protein transport and sorting.
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27
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Van der Luit A, Budde M, Zerp S, Caan W, Klarenbeek J, Verheij M, van Blitterswijk W. Resistance to alkyl-lysophospholipid-induced apoptosis due to downregulated sphingomyelin synthase 1 expression with consequent sphingomyelin- and cholesterol-deficiency in lipid rafts. Biochem J 2007; 401:541-9. [PMID: 17049047 PMCID: PMC1820802 DOI: 10.1042/bj20061178] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The ALP (alkyl-lysophospholipid) edelfosine (1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine; Et-18-OCH3) induces apoptosis in S49 mouse lymphoma cells. To this end, ALP is internalized by lipid raft-dependent endocytosis and inhibits phosphatidylcholine synthesis. A variant cell-line, S49AR, which is resistant to ALP, was shown previously to be unable to internalize ALP via this lipid raft pathway. The reason for this uptake failure is not understood. In the present study, we show that S49AR cells are unable to synthesize SM (sphingomyelin) due to down-regulated SMS1 (SM synthase 1) expression. In parental S49 cells, resistance to ALP could be mimicked by small interfering RNA-induced SMS1 suppression, resulting in SM deficiency and blockage of raft-dependent internalization of ALP and induction of apoptosis. Similar results were obtained by treatment of the cells with myriocin/ISP-1, an inhibitor of general sphingolipid synthesis, or with U18666A, a cholesterol homoeostasis perturbing agent. U18666A is known to inhibit Niemann-Pick C1 protein-dependent vesicular transport of cholesterol from endosomal compartments to the trans-Golgi network and the plasma membrane. U18666A reduced cholesterol partitioning in detergent-resistant lipid rafts and inhibited SM synthesis in S49 cells, causing ALP resistance similar to that observed in S49AR cells. The results are explained by the strong physical interaction between (newly synthesized) SM and available cholesterol at the Golgi, where they facilitate lipid raft formation. We propose that ALP internalization by lipid-raft-dependent endocytosis represents the retrograde route of a constitutive SMS1- and lipid-raft-dependent membrane vesicular recycling process.
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Affiliation(s)
- Arnold H. Van der Luit
- *Division of Cellular Biochemistry, The Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Marianne Budde
- *Division of Cellular Biochemistry, The Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Shuraila Zerp
- †Department of Radiotherapy, The Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Wendy Caan
- *Division of Cellular Biochemistry, The Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Jeffrey B. Klarenbeek
- *Division of Cellular Biochemistry, The Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Marcel Verheij
- †Department of Radiotherapy, The Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Wim J. van Blitterswijk
- *Division of Cellular Biochemistry, The Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
- To whom correspondence should be addressed (email )
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28
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Zal T, Zal MA, Lotz C, Goergen CJ, Gascoigne NRJ. Spectral shift of fluorescent dye FM4-64 reveals distinct microenvironment of nuclear envelope in living cells. Traffic 2006; 7:1607-13. [PMID: 17052249 DOI: 10.1111/j.1600-0854.2006.00498.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report a distinct microenvironment within the nuclear envelope (NE) in living cells revealed by a spectral shift of the fluorescent dye FM4-64 (N-(3-triethylammoniumpropyl)-4-(p-diethylaminophenylhexatrienyl)-pyridinium 2Br). The dye readily translocated to the NE at physiological temperature where it exhibited enhanced fluorescence when excited at 620-650 nm in contrast to 480-520 nm excitation in the endocytic pathway and in the endoplasmic reticulum (ER). In vitro data indicated that the dye reveals an enrichment of negatively charged lipids, presumably due to local phospholipid synthesis. Dual-excitation imaging of FM4-64 in relation to lamina-associated polypeptide-1-green fluorescent protein during mitosis suggested that the disassembly of NE preserves microscale lipid complexes in the ER. Convolutions of NE in cancer or primary cells were readily visualized, and killing of tumor cells by T cells was marked by sudden loss of the long-wavelength excited fluorescence in the NE coincident with apoptosis. This report of FM4-64 as the first vital dye sensitive to the NE environment opens new ways for real-time visualization and functional studies of the NE.
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Affiliation(s)
- Tomasz Zal
- Department of Immunology, The Scripps Research Institute, La Jolla, CA 92037, USA.
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