1
|
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.
Collapse
|
2
|
Christerson U, Keita ÅV, Winberg ME, Söderholm JD, Gustafson-Svärd C. Possible Involvement of Intracellular Calcium-Independent Phospholipase A 2 in the Release of Secretory Phospholipases from Mast Cells-Increased Expression in Ileal Mast Cells of Crohn's Disease. Cells 2019; 8:cells8070672. [PMID: 31277247 PMCID: PMC6678282 DOI: 10.3390/cells8070672] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 06/27/2019] [Accepted: 07/01/2019] [Indexed: 12/24/2022] Open
Abstract
Increased activity of secretory phospholipases A2 (sPLA2) type-II was previously observed in ileum of Crohn’s disease (CD). Our aims were to explore the involvement of calcium-independent (i)PLA2β in the release of sPLA2s from the human mast cell (MC) line (HMC-1) and investigate expressions of cytosolic (c)PLA2α, iPLA2β, sPLA2-IIA and sPLA2-V in MCs of CD ileum. The release of sPLA2 was investigated in HMC-1 by immunocytochemistry and ELISA. The expression intensities of PLA2s in mucosal MCs, and the proportion of PLA2-positive MCs, were investigated in normal ileum and in ileum from patients with CD by immunohistochemistry. The calcium ionophore-stimulated release of sPLA2-IIA and sPLA2-V from HMC-1 was reduced by the iPLA2-inhibitor bromoenol lactone. All four PLA2s were detectable in mucosal MCs, both in normal ileum and in CD, but the proportion of iPLA2β-containing mucosal MCs and the expression intensity of sPLA2-IIA was increased in CD. Results indicate that iPLA2β is involved in the secretion of sPLA2s from HMC-1, and suggest that iPLA2β-mediated release of sPLA2 from intestinal MCs may contribute to CD pathophysiology. Ex vivo studies on isolated mucosal mast cells are however needed to clarify the precise role of MC PLA2s in the inflammatory processes of CD.
Collapse
Affiliation(s)
- Ulrika Christerson
- Department of Chemistry and Biomedical Sciences, Faculty of Health and Life Sciences, Linnaeus University, 391 82 Kalmar, Sweden
| | - Åsa V Keita
- Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics & Oncology, Linköping University, 581 85 Linköping, Sweden
| | - Martin E Winberg
- Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics & Oncology, Linköping University, 581 85 Linköping, Sweden
| | - Johan D Söderholm
- Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics & Oncology, Linköping University, 581 85 Linköping, Sweden
- Department of Surgery, County Council of Östergötland, 581 85 Linköping, Sweden
| | - Christina Gustafson-Svärd
- Department of Chemistry and Biomedical Sciences, Faculty of Health and Life Sciences, Linnaeus University, 391 82 Kalmar, Sweden
| |
Collapse
|
3
|
Melero A, Chiaruttini N, Karashima T, Riezman I, Funato K, Barlowe C, Riezman H, Roux A. Lysophospholipids Facilitate COPII Vesicle Formation. Curr Biol 2018; 28:1950-1958.e6. [PMID: 29887313 PMCID: PMC6013297 DOI: 10.1016/j.cub.2018.04.076] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 03/05/2018] [Accepted: 04/24/2018] [Indexed: 12/15/2022]
Abstract
Coat protein complex II (COPII) proteins form vesicles from the endoplasmic reticulum to export cargo molecules to the Golgi apparatus. Among the many proteins involved in this process, Sec12 is a key regulator, functioning as the guanosine diphosphate (GDP) exchange factor for Sar1p, the small guanosine triphosphatase (GTPase) that initiates COPII assembly. Here we show that overexpression of phospholipase B3 in the thermosensitive sec12-4 mutant partially restores growth and protein transport at non-permissive temperatures. Lipidomics analyses of these cells show a higher content of lysophosphatidylinositol (lysoPI), consistent with the lipid specificity of PLB3. Furthermore, we show that lysoPI is specifically enriched in COPII vesicles isolated from in vitro budding assays. As these results suggested that lysophospholipids could facilitate budding under conditions of defective COPII coat dynamics, we reconstituted COPII binding onto giant liposomes with purified proteins and showed that lysoPI decreases membrane rigidity and enhances COPII recruitment to liposomes. Our results support a mechanical facilitation of COPII budding by lysophospholipids. COPII mutant sec12-4 is rescued by the overexpression of an ER resident phospholipase Lipidomic analysis of COPII vesicles shows enrichment in lysophospholipids Recruitment of COPII proteins to liposomes increases in presence of lysophospholipids Lysophosphatidylinositol lowers the rigidity of membranes in vitro
Collapse
Affiliation(s)
- Alejandro Melero
- Department of Biochemistry, University of Geneva, 1211 Geneva, Switzerland; Swiss National Centre for Competence in Research in Chemical Biology, 1211 Geneva, Switzerland
| | | | - Takefumi Karashima
- Department of Bioresource Science and Technology, Hiroshima University, Hiroshima 739-8528, Japan
| | - Isabelle Riezman
- Department of Biochemistry, University of Geneva, 1211 Geneva, Switzerland
| | - Kouichi Funato
- Department of Bioresource Science and Technology, Hiroshima University, Hiroshima 739-8528, Japan
| | - Charles Barlowe
- Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, NH 03755-3844, USA
| | - Howard Riezman
- Department of Biochemistry, University of Geneva, 1211 Geneva, Switzerland; Swiss National Centre for Competence in Research in Chemical Biology, 1211 Geneva, Switzerland.
| | - Aurélien Roux
- Department of Biochemistry, University of Geneva, 1211 Geneva, Switzerland; Swiss National Centre for Competence in Research in Chemical Biology, 1211 Geneva, Switzerland.
| |
Collapse
|
4
|
Drecourt A, Babdor J, Dussiot M, Petit F, Goudin N, Garfa-Traoré M, Habarou F, Bole-Feysot C, Nitschké P, Ottolenghi C, Metodiev MD, Serre V, Desguerre I, Boddaert N, Hermine O, Munnich A, Rötig A. Impaired Transferrin Receptor Palmitoylation and Recycling in Neurodegeneration with Brain Iron Accumulation. Am J Hum Genet 2018; 102:266-277. [PMID: 29395073 DOI: 10.1016/j.ajhg.2018.01.003] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 01/05/2018] [Indexed: 12/29/2022] Open
Abstract
Neurodegeneration with brain iron accumulation (NBIA) is a genetically heterogeneous condition characterized by progressive dystonia with iron accumulation in the basal ganglia. How NBIA-associated mutations trigger iron overload remains poorly understood. After studying fibroblast cell lines from subjects carrying both known and unreported biallelic mutations in CRAT and REPS1, we ascribe iron overload to the abnormal recycling of transferrin receptor (TfR1) and the reduction of TfR1 palmitoylation in NBIA. Moreover, we describe palmitoylation as a hitherto unreported level of post-translational TfR1 regulation. A widely used antimalarial agent, artesunate, rescued abnormal TfR1 palmitoylation in cultured fibroblasts of NBIA subjects. These observations suggest therapeutic strategies aimed at targeting impaired TfR1 recycling and palmitoylation in NBIA.
Collapse
|
5
|
Gadila SKG, Kim K. Cargo trafficking from the trans-Golgi network towards the endosome. Biol Cell 2016; 108:205-18. [DOI: 10.1111/boc.201600001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 03/30/2016] [Accepted: 03/31/2016] [Indexed: 11/28/2022]
Affiliation(s)
| | - Kyoungtae Kim
- Department of Biology; Missouri State University; Springfield MO 65807 USA
| |
Collapse
|
6
|
Davids M, Kane MS, He M, Wolfe LA, Li X, Raihan MA, Chao KR, Bone WP, Boerkoel CF, Gahl WA, Toro C. Disruption of Golgi morphology and altered protein glycosylation in PLA2G6-associated neurodegeneration. J Med Genet 2015; 53:180-9. [PMID: 26668131 DOI: 10.1136/jmedgenet-2015-103338] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 11/09/2015] [Indexed: 01/07/2023]
Abstract
BACKGROUND Mutations in PLA2G6, which encodes the calcium-independent phospholipase A2 group VI, cause neurodegeneration and diffuse cortical Lewy body formation by a yet undefined mechanism. We assessed whether altered protein glycosylation due to abnormal Golgi morphology might be a factor in the pathology of this disease. METHODS Three patients presented with PLA2G6-associated neurodegeneration (PLAN); two had infantile neuroaxonal dystrophy (INAD) and one had adult-onset dystonia-parkinsonism. We analysed protein N-linked and O-linked glycosylation in cerebrospinal fluid, plasma, urine, and cultured skin fibroblasts using high performance liquid chromatography (HPLC) and matrix-assisted laser desorption ionization--time of flight/mass spectrometry (MALDI-TOF/MS). We also assessed sialylation and Golgi morphology in cultured fibroblasts by immunofluorescence and performed rescue experiments using a lentiviral vector. RESULTS The patients with INAD had PLA2G6 mutations NM_003560.2: c.[950G>T];[426-1077dup] and c.[1799G>A];[2221C>T] and the patient with dystonia-parkinsonism had PLA2G6 mutations NM_003560.2: c.[609G>A];[2222G>A]. All three patients had altered Golgi morphology and abnormalities of protein O-linked glycosylation and sialylation in cultured fibroblasts that were rescued by lentiviral overexpression of wild type PLA2G6. CONCLUSIONS Our findings add altered Golgi morphology, O-linked glycosylation and sialylation defects to the phenotypical spectrum of PLAN; these pathways are essential for correct processing and distribution of proteins. Lewy body and Tau pathology, two neuropathological features of PLAN, could emerge from these defects. Therefore, Golgi morphology, O-linked glycosylation and sialylation may play a role in the pathogenesis of PLAN and perhaps other neurodegenerative disorders.
Collapse
Affiliation(s)
- Mariska Davids
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - Megan S Kane
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - Miao He
- Department of Pathology and Laboratory of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA The Michael J Palmieri Metabolic Laboratory, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Lynne A Wolfe
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - Xueli Li
- Department of Pathology and Laboratory of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA The Michael J Palmieri Metabolic Laboratory, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Mohd A Raihan
- Department of Pathology and Laboratory of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA The Michael J Palmieri Metabolic Laboratory, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Katherine R Chao
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - William P Bone
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - Cornelius F Boerkoel
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - William A Gahl
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - Camilo Toro
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| |
Collapse
|
7
|
Mazzucotelli E, Trono D. Cloning, expression analysis, and functional characterization of two secretory phospholipases A2 in durum wheat (Triticum durum Desf.). PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2015; 241:295-306. [PMID: 26706080 DOI: 10.1016/j.plantsci.2015.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 10/16/2015] [Accepted: 10/17/2015] [Indexed: 06/05/2023]
Abstract
We previously isolated four cDNAs in durum wheat, TdsPLA2I, TdsPLA2II, TdsPLA2III and TdsPLA2IV, that encode proteins with homology to plant secretory phospholipases A2 (sPLA2s) (Verlotta et al., Int. J. Mol. Sci., 14, 2013, 5146-5169). In this study, we have further characterized TdsPLA2II and TdsPLA2III sequences that, on the basis of our previous findings, might encode sPLA2 isoforms with different features. Functional analysis revealed that, similarly to other known sPLA2s, TdsPLA2II and TdsPLA2III have an optimum at pH 9.0, require Ca(2+), are heat stable, and are inhibited by the disulfide-bond-reducing agent dithiothreitol. However, differences emerged between these TdsPLA2 isoforms. Transcript analysis revealed that the TdsPLA2III gene is highly up-regulated under different environmental stresses; conversely, the TdsPLA2II gene is expressed at constant levels under almost all of the stress conditions examined. Moreover, TdsPLA2II is saturated at micromolar substrate and Ca(2+) concentrations, whereas TdsPLA2III requires millimolar concentrations to reach maximal activity. This suggests that TdsPLA2II normally functions under optimal conditions in vivo, whereas TdsPLA2III is only partially activated, depending on the specific phospholipid and Ca(2+) levels. Altogether these data lead to the hypothesis that in vivo TdsPLA2II and TdsPLA2III are differently regulated at both molecular and biochemical level and that TdsPLA2III plays a major role in durum wheat response to adverse environmental conditions.
Collapse
MESH Headings
- Amino Acid Sequence
- Cloning, Molecular
- DNA, Complementary/genetics
- DNA, Complementary/metabolism
- DNA, Plant/genetics
- DNA, Plant/metabolism
- Gene Expression Regulation, Plant
- Molecular Sequence Data
- Phospholipases A2, Secretory/genetics
- Phospholipases A2, Secretory/metabolism
- Phylogeny
- Plant Proteins/genetics
- Plant Proteins/metabolism
- RNA, Plant/genetics
- RNA, Plant/metabolism
- Sequence Alignment
- Triticum/enzymology
- Triticum/genetics
- Triticum/metabolism
Collapse
Affiliation(s)
- Elisabetta Mazzucotelli
- Consiglio per la Ricerca in Agricoltura e l'Analisi dell'Economia Agraria, Centro di Ricerca per la Genomica Vegetale, Via San Protaso 302, 29017 Fiorenzuola d'Arda, Italy
| | - Daniela Trono
- Consiglio per la Ricerca in Agricoltura e l'Analisi dell'Economia Agraria, Centro di Ricerca per la Cerealicoltura, S.S. 673, Km 25,200, 71122 Foggia, Italy.
| |
Collapse
|
8
|
Abstract
Heterotrimeric G proteins transduce the ligand binding of transmembrane G protein coupled receptors into a variety of intracellular signaling pathways. Recently, heterotrimeric Gβγ subunit signaling at the Golgi complex has been shown to regulate the formation of vesicular transport carriers that deliver cargo from the Golgi to the plasma membrane. In addition to vesicles, membrane tubules have also been shown to mediate export from the Golgi complex, which requires the activity of cytoplasmic phospholipase A2 (PLA2) enzyme activity. Through the use of an in vitro reconstitution assay with isolated Golgi complexes, we provide evidence that Gβ1γ2 signaling also stimulates Golgi membrane tubule formation. In addition, we show that an inhibitor of Gβγ activation of PLA2 enzymes inhibits in vitro Golgi membrane tubule formation. Additionally, purified Gβγ protein stimulates membrane tubules in the presence of low (sub-threshold) cytosol concentrations. Importantly, this Gβγ stimulation of Golgi membrane tubule formation was inhibited by treatment with the PLA2 antagonist ONO-RS-082. These studies indicate that Gβ1γ2 signaling activates PLA2 enzymes required for Golgi membrane tubule formation, thus establishing a new layer of regulation for this process.
Collapse
Affiliation(s)
- Marie E Bechler
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - William J Brown
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| |
Collapse
|
9
|
Martínez-Alonso E, Tomás M, Martínez-Menárguez JA. Golgi tubules: their structure, formation and role in intra-Golgi transport. Histochem Cell Biol 2013; 140:327-39. [PMID: 23812035 DOI: 10.1007/s00418-013-1114-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/16/2013] [Indexed: 11/28/2022]
Abstract
Tubules are common Golgi elements that can form extensive networks associated with the cis-, lateral and trans-Golgi sides, but despite this, they have almost been forgotten for decades. The molecular mechanisms involved in their formation, elongation and fission are only just beginning to be understood. However, the role of these membranes is not well understood. In the present review, we analyze the mechanisms that induce Golgi tubulation or, conversely, disrupt tubules in order to throw some lights on the nature of these elements. The putative role of these elements in the framework of current models for intra-Golgi transport is also discussed.
Collapse
Affiliation(s)
- Emma Martínez-Alonso
- Department of Cell Biology and Histology, Medical School, University of Murcia, 30100 Murcia, Spain
| | | | | |
Collapse
|
10
|
Abstract
The Golgi complex is considered the central station of the secretory pathway where cargo proteins and lipids are properly modified, classified, packed into specific carriers and delivered to their final destinations. Early electron microscope studies showed the extraordinary structural complexity of this organelle. However, despite the large volume of incoming and outgoing traffic, it is able to maintain its architecture, although it is also flexible enough to adapt to the functional status of the cell. Many components of the molecular machinery involved in membrane traffic and other Golgi functions have been identified. However, some basic aspects of Golgi functioning remain unsolved. For instance, how cargo moves through the stack remains controversial and two classical models have been proposed: vesicular transport and cisternal maturation. Since neither of these models explains all the experimental data, a combination of these models as well as new models have been proposed. In this context, the specific role of the cisternae, vesicles and tubules needs to be clarified. In this review, we summarize our current knowledge of the Golgi organization and function, focusing on the mechanisms of intra-Golgi transport.
Collapse
|
11
|
Martínez-Alonso E, Tomás M, Martínez-Menárguez JA. Morpho-functional architecture of the Golgi complex of neuroendocrine cells. Front Endocrinol (Lausanne) 2013; 4:41. [PMID: 23543640 PMCID: PMC3610015 DOI: 10.3389/fendo.2013.00041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Accepted: 03/14/2013] [Indexed: 12/22/2022] Open
Abstract
In neuroendocrine cells, prohormones move from the endoplasmic reticulum to the Golgi complex (GC), where they are sorted and packed into secretory granules. The GC is considered the central station of the secretory pathway of proteins and lipids en route to their final destination. In most mammalian cells, it is formed by several stacks of cisternae connected by tubules, forming a continuous ribbon. This organelle shows an extraordinary structural and functional complexity, which is exacerbated by the fact that its architecture is cell type specific and also tuned by the functional status of the cell. It is, indeed, one the most beautiful cellular organelles and, for that reason, perhaps the most extensively photographed by electron microscopists. In recent decades, an exhaustive dissection of the molecular machinery involved in membrane traffic and other Golgi functions has been carried out. Concomitantly, detailed morphological studies have been performed, including 3D analysis by electron tomography, and the precise location of key proteins has been identified by immunoelectron microscopy. Despite all this effort, some basic aspects of Golgi functioning remain unsolved. For instance, the mode of intra-Golgi transport is not known, and two opposing theories (vesicular transport and cisternal maturation models) have polarized the field for many years. Neither of these theories explains all the experimental data so that new theories and combinations thereof have recently been proposed. Moreover, the specific role of the small vesicles and tubules which surround the stacks needs to be clarified. In this review, we summarize our current knowledge of the Golgi architecture in relation with its function and the mechanisms of intra-Golgi transport. Within the same framework, the characteristics of the GC of neuroendocrine cells are analyzed.
Collapse
Affiliation(s)
- Emma Martínez-Alonso
- Department of Cell Biology and Histology, Medical School, University of MurciaMurcia, Spain
| | - Mónica Tomás
- Department of Human Anatomy and Embryology, Medical School, Valencia UniversityValencia, Spain
| | - José A. Martínez-Menárguez
- Department of Cell Biology and Histology, Medical School, University of MurciaMurcia, Spain
- *Correspondence: José A. Martínez-Menárguez, Department of Cell Biology and Histology, Medical School, University of Murcia, 30100 Murcia, Spain. e-mail:
| |
Collapse
|
12
|
Kuhle K, Flieger A. Legionella phospholipases implicated in virulence. Curr Top Microbiol Immunol 2013; 376:175-209. [PMID: 23925490 DOI: 10.1007/82_2013_348] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Phospholipases are diverse enzymes produced in eukaryotic hosts and their bacterial pathogens. Several pathogen phospholipases have been identified as major virulence factors acting mainly in two different modes: on the one hand, they have the capability to destroy host membranes and on the other hand they are able to manipulate host signaling pathways. Reaction products of bacterial phospholipases may act as secondary messengers within the host and therefore influence inflammatory cascades and cellular processes, such as proliferation, migration, cytoskeletal changes as well as membrane traffic. The lung pathogen and intracellularly replicating bacterium Legionella pneumophila expresses a variety of phospholipases potentially involved in disease-promoting processes. So far, genes encoding 15 phospholipases A, three phospholipases C, and one phospholipase D have been identified. These cell-associated or secreted phospholipases may contribute to intracellular establishment, to egress of the pathogen from the host cell, and to the observed lung pathology. Due to the importance of phospholipase activities for host cell processes, it is conceivable that the pathogen enzymes may mimic or substitute host cell phospholipases to drive processes for the pathogen's benefit. The following chapter summarizes the current knowledge on the L. pneumophila phospholipases, especially their substrate specificity, localization, mode of secretion, and impact on host cells.
Collapse
Affiliation(s)
- Katja Kuhle
- FG 11 - Division of Enteropathogenic Bacteria and Legionella, Robert Koch-Institut, Burgstr. 37, 38855, Wernigerode, Germany
| | | |
Collapse
|
13
|
Morrison K, Witte K, Mayers JR, Schuh AL, Audhya A. Roles of acidic phospholipids and nucleotides in regulating membrane binding and activity of a calcium-independent phospholipase A2 isoform. J Biol Chem 2012; 287:38824-34. [PMID: 23007400 DOI: 10.1074/jbc.m112.391508] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Phospholipase A(2) activity plays key roles in generating lipid second messengers and regulates membrane topology through the generation of asymmetric lysophospholipids. In particular, the Group VIA phospholipase A(2) (GVIA-iPLA(2)) subfamily of enzymes functions independently of calcium within the cytoplasm of cells and has been implicated in numerous cellular processes, including proliferation, apoptosis, and membrane transport steps. However, mechanisms underlying the spatial and temporal regulation of these enzymes have remained mostly unexplored. Here, we examine the subset of Caenorhabditis elegans lipases that harbor a consensus motif common to members of the GVIA-iPLA(2) subfamily. Based on sequence homology, we identify IPLA-1 as the closest C. elegans homolog of human GVIA-iPLA(2) enzymes and use a combination of liposome interaction studies to demonstrate a role for acidic phospholipids in regulating GVIA-iPLA(2) function. Our studies indicate that IPLA-1 binds directly to multiple acidic phospholipids, including phosphatidylserine, phosphatidylglycerol, cardiolipin, phosphatidic acid, and phosphorylated derivatives of phosphatidylinositol. Moreover, the presence of these acidic lipids dramatically elevates the specific activity of IPLA-1 in vitro. We also found that the addition of ATP and ADP promote oligomerization of IPLA-1, which probably underlies the stimulatory effect of nucleotides on its activity. We propose that membrane composition and the presence of nucleotides play key roles in recruiting and modulating GVIA-iPLA(2) activity in cells.
Collapse
Affiliation(s)
- Kylee Morrison
- Department of Biomolecular Chemistry, University of Wisconsin-Madison Medical School, Madison, Wisconsin 53706, USA
| | | | | | | | | |
Collapse
|
14
|
Branched F-actin as a negative regulator of cilia formation. Exp Cell Res 2012; 319:147-51. [PMID: 22975729 DOI: 10.1016/j.yexcr.2012.08.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Revised: 08/30/2012] [Accepted: 08/31/2012] [Indexed: 01/18/2023]
Abstract
Cilia dysfunction leads to developmental defects and also a spectrum of human diseases termed ciliopathies. The actin cytoskeleton is a highly dynamic network and involved in many important biological processes, such as cell migration and membrane trafficking. Recently, actin dynamics has been shown to play a critical role in ciliogenesis. This review summarizes these results and provides insight into possible mechanisms.
Collapse
|
15
|
Modular organization of the mammalian Golgi apparatus. Curr Opin Cell Biol 2012; 24:467-74. [PMID: 22726585 DOI: 10.1016/j.ceb.2012.05.009] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Accepted: 05/29/2012] [Indexed: 02/07/2023]
Abstract
The Golgi apparatus is essential for post-translational modifications and sorting of proteins in the secretory pathway. In addition, it further performs a broad range of specialized functions. This functional diversity is achieved by combining basic morphological modules of cisternae into higher ordered structures. Linking cisternae into stacks that are further connected through tubules into a continuous Golgi ribbon greatly increases its efficiency and expands its repertoire of functions. During cell division, the different modules of the Golgi are inherited by different mechanisms to maintain its functional and morphological composition.
Collapse
|
16
|
Bechler ME, de Figueiredo P, Brown WJ. A PLA1-2 punch regulates the Golgi complex. Trends Cell Biol 2011; 22:116-24. [PMID: 22130221 DOI: 10.1016/j.tcb.2011.10.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 10/19/2011] [Accepted: 10/20/2011] [Indexed: 12/14/2022]
Abstract
The mammalian Golgi complex, trans Golgi network (TGN) and ER-Golgi intermediate compartment (ERGIC) are comprised of membrane cisternae, coated vesicles and membrane tubules, all of which contribute to membrane trafficking and maintenance of their unique architectures. Recently, a new cast of players was discovered to regulate the Golgi and ERGIC: four unrelated cytoplasmic phospholipase A (PLA) enzymes, cPLA(2)α (GIVA cPLA(2)), PAFAH Ib (GVIII PLA(2)), iPLA(2)-β (GVIA-2 iPLA(2)) and iPLA(1)γ. These ubiquitously expressed enzymes regulate membrane trafficking from specific Golgi subcompartments, although there is evidence for some functional redundancy between PAFAH Ib and cPLA(2)α. Three of these enzymes, PAFAH Ib, cPLA(2)α and iPLA(2)-β, exert effects on Golgi structure and function by inducing the formation of membrane tubules. We review our current understanding of how PLA enzymes regulate Golgi and ERGIC morphology and function.
Collapse
Affiliation(s)
- Marie E Bechler
- Department of Molecular Biology & Genetics, Cornell University, Ithaca, NY 14853, USA
| | | | | |
Collapse
|
17
|
Lang C, Flieger A. Characterisation of Legionella pneumophila phospholipases and their impact on host cells. Eur J Cell Biol 2011; 90:903-12. [DOI: 10.1016/j.ejcb.2010.12.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 12/08/2010] [Accepted: 12/13/2010] [Indexed: 01/16/2023] Open
|
18
|
Role of phospholipase A(2) in retrograde transport of ricin. Toxins (Basel) 2011; 3:1203-19. [PMID: 22069763 PMCID: PMC3202871 DOI: 10.3390/toxins3091203] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 08/25/2011] [Accepted: 09/16/2011] [Indexed: 12/03/2022] Open
Abstract
Ricin is a protein toxin classified as a bioterror agent, for which there are no known treatment options available after intoxication. It is composed of an enzymatically active A-chain connected by a disulfide bond to a cell binding B-chain. After internalization by endocytosis, ricin is transported retrogradely to the Golgi and ER, from where the ricin A-chain is translocated to the cytosol where it inhibits protein synthesis and thus induces cell death. We have identified cytoplasmic phospholipase A2 (PLA2) as an important factor in ricin retrograde transport. Inhibition of PLA2 protects against ricin challenge, however the toxin can still be endocytosed and transported to the Golgi. Interestingly, ricin transport from the Golgi to the ER is strongly impaired in response to PLA2 inhibition. Confocal microscopy analysis shows that ricin is still colocalized with the trans-Golgi marker TGN46 in the presence of PLA2 inhibitor, but less is colocalized with the cis-Golgi marker GM130. We propose that PLA2 inhibition results in impaired ricin transport through the Golgi stack, thus preventing it from reaching the ER. Consequently, ricin cannot be translocated to the cytosol to exert its toxic action.
Collapse
|