1
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Cabukusta B, Borst Pauwels S, Akkermans JJLL, Blomberg N, Mulder AA, Koning RI, Giera M, Neefjes J. The ORP9-ORP11 dimer promotes sphingomyelin synthesis. eLife 2024; 12:RP91345. [PMID: 39106189 PMCID: PMC11302984 DOI: 10.7554/elife.91345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/09/2024] Open
Abstract
Numerous lipids are heterogeneously distributed among organelles. Most lipid trafficking between organelles is achieved by a group of lipid transfer proteins (LTPs) that carry lipids using their hydrophobic cavities. The human genome encodes many intracellular LTPs responsible for lipid trafficking and the function of many LTPs in defining cellular lipid levels and distributions is unclear. Here, we created a gene knockout library targeting 90 intracellular LTPs and performed whole-cell lipidomics analysis. This analysis confirmed known lipid disturbances and identified new ones caused by the loss of LTPs. Among these, we found major sphingolipid imbalances in ORP9 and ORP11 knockout cells, two proteins of previously unknown function in sphingolipid metabolism. ORP9 and ORP11 form a heterodimer to localize at the ER-trans-Golgi membrane contact sites, where the dimer exchanges phosphatidylserine (PS) for phosphatidylinositol-4-phosphate (PI(4)P) between the two organelles. Consequently, loss of either protein causes phospholipid imbalances in the Golgi apparatus that result in lowered sphingomyelin synthesis at this organelle. Overall, our LTP knockout library toolbox identifies various proteins in control of cellular lipid levels, including the ORP9-ORP11 heterodimer, which exchanges PS and PI(4)P at the ER-Golgi membrane contact site as a critical step in sphingomyelin synthesis in the Golgi apparatus.
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Affiliation(s)
- Birol Cabukusta
- Cell and Chemical Biology, Oncode Institute, Leiden University Medical CenterLeidenNetherlands
| | - Shalom Borst Pauwels
- Cell and Chemical Biology, Oncode Institute, Leiden University Medical CenterLeidenNetherlands
| | - Jimmy JLL Akkermans
- Cell and Chemical Biology, Oncode Institute, Leiden University Medical CenterLeidenNetherlands
| | - Niek Blomberg
- Centre for Proteomics and Metabolomics, Leiden University Medical CenterLeidenNetherlands
| | - Aat A Mulder
- Electron Microscopy Facility, Cell and Chemical Biology, Leiden University Medical CenterLeidenNetherlands
| | - Roman I Koning
- Electron Microscopy Facility, Cell and Chemical Biology, Leiden University Medical CenterLeidenNetherlands
| | - Martin Giera
- Centre for Proteomics and Metabolomics, Leiden University Medical CenterLeidenNetherlands
| | - Jacques Neefjes
- Cell and Chemical Biology, Oncode Institute, Leiden University Medical CenterLeidenNetherlands
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2
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Todorov-Völgyi K, González-Gallego J, Müller SA, Beaufort N, Malik R, Schifferer M, Todorov MI, Crusius D, Robinson S, Schmidt A, Körbelin J, Bareyre F, Ertürk A, Haass C, Simons M, Paquet D, Lichtenthaler SF, Dichgans M. Proteomics of mouse brain endothelium uncovers dysregulation of vesicular transport pathways during aging. NATURE AGING 2024; 4:595-612. [PMID: 38519806 DOI: 10.1038/s43587-024-00598-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 02/20/2024] [Indexed: 03/25/2024]
Abstract
Age-related decline in brain endothelial cell (BEC) function contributes critically to neurological disease. Comprehensive atlases of the BEC transcriptome have become available, but results from proteomic profiling are lacking. To gain insights into endothelial pathways affected by aging, we developed a magnetic-activated cell sorting-based mouse BEC enrichment protocol compatible with proteomics and resolved the profiles of protein abundance changes during aging. Unsupervised cluster analysis revealed a segregation of age-related protein dynamics with biological functions, including a downregulation of vesicle-mediated transport. We found a dysregulation of key regulators of endocytosis and receptor recycling (most prominently Arf6), macropinocytosis and lysosomal degradation. In gene deletion and overexpression experiments, Arf6 affected endocytosis pathways in endothelial cells. Our approach uncovered changes not picked up by transcriptomic studies, such as accumulation of vesicle cargo and receptor ligands, including Apoe. Proteomic analysis of BECs from Apoe-deficient mice revealed a signature of accelerated aging. Our findings provide a resource for analysing BEC function during aging.
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Affiliation(s)
- Katalin Todorov-Völgyi
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany.
| | - Judit González-Gallego
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
- Graduate School of Systemic Neuroscience (GSN), University Hospital, LMU Munich, Munich, Germany
| | - Stephan A Müller
- German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany
- Neuroproteomics, School of Medicine and Health, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Nathalie Beaufort
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
| | - Rainer Malik
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
| | - Martina Schifferer
- German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Mihail Ivilinov Todorov
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
- Institute for Tissue Engineering and Regenerative Medicine (iTERM), Helmholtz Zentrum München, Neuherberg, Germany
| | - Dennis Crusius
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
| | - Sophie Robinson
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
- Graduate School of Systemic Neuroscience (GSN), University Hospital, LMU Munich, Munich, Germany
- German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany
| | - Andree Schmidt
- German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany
- Neuroproteomics, School of Medicine and Health, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Jakob Körbelin
- Department of Oncology, Hematology and Bone Marrow Transplantation with Section Pneumology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Florence Bareyre
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
| | - Ali Ertürk
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
- Institute for Tissue Engineering and Regenerative Medicine (iTERM), Helmholtz Zentrum München, Neuherberg, Germany
| | - Christian Haass
- German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
- Division of Metabolic Biochemistry, Biomedical Center Munich (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Mikael Simons
- German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Dominik Paquet
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Stefan F Lichtenthaler
- German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany
- Neuroproteomics, School of Medicine and Health, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Martin Dichgans
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany.
- German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany.
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
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3
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Siegfried H, Farkouh G, Le Borgne R, Pioche-Durieu C, De Azevedo Laplace T, Verraes A, Daunas L, Verbavatz JM, Heuzé ML. The ER tether VAPA is required for proper cell motility and anchors ER-PM contact sites to focal adhesions. eLife 2024; 13:e85962. [PMID: 38446032 PMCID: PMC10917420 DOI: 10.7554/elife.85962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 02/07/2024] [Indexed: 03/07/2024] Open
Abstract
Cell motility processes highly depend on the membrane distribution of Phosphoinositides, giving rise to cytoskeleton reshaping and membrane trafficking events. Membrane contact sites serve as platforms for direct lipid exchange and calcium fluxes between two organelles. Here, we show that VAPA, an ER transmembrane contact site tether, plays a crucial role during cell motility. CaCo2 adenocarcinoma epithelial cells depleted for VAPA exhibit several collective and individual motility defects, disorganized actin cytoskeleton and altered protrusive activity. During migration, VAPA is required for the maintenance of PI(4)P and PI(4,5)P2 levels at the plasma membrane, but not for PI(4)P homeostasis in the Golgi and endosomal compartments. Importantly, we show that VAPA regulates the dynamics of focal adhesions (FA) through its MSP domain, is essential to stabilize and anchor ventral ER-PM contact sites to FA, and mediates microtubule-dependent FA disassembly. To conclude, our results reveal unknown functions for VAPA-mediated membrane contact sites during cell motility and provide a dynamic picture of ER-PM contact sites connection with FA mediated by VAPA.
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Affiliation(s)
- Hugo Siegfried
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013ParisFrance
| | - Georges Farkouh
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013ParisFrance
| | - Rémi Le Borgne
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013ParisFrance
| | | | | | - Agathe Verraes
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013ParisFrance
| | - Lucien Daunas
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013ParisFrance
| | | | - Mélina L Heuzé
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013ParisFrance
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4
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Clemente TM, Angara RK, Gilk SD. Establishing the intracellular niche of obligate intracellular vacuolar pathogens. Front Cell Infect Microbiol 2023; 13:1206037. [PMID: 37645379 PMCID: PMC10461009 DOI: 10.3389/fcimb.2023.1206037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 07/21/2023] [Indexed: 08/31/2023] Open
Abstract
Obligate intracellular pathogens occupy one of two niches - free in the host cell cytoplasm or confined in a membrane-bound vacuole. Pathogens occupying membrane-bound vacuoles are sequestered from the innate immune system and have an extra layer of protection from antimicrobial drugs. However, this lifestyle presents several challenges. First, the bacteria must obtain membrane or membrane components to support vacuole expansion and provide space for the increasing bacteria numbers during the log phase of replication. Second, the vacuole microenvironment must be suitable for the unique metabolic needs of the pathogen. Third, as most obligate intracellular bacterial pathogens have undergone genomic reduction and are not capable of full metabolic independence, the bacteria must have mechanisms to obtain essential nutrients and resources from the host cell. Finally, because they are separated from the host cell by the vacuole membrane, the bacteria must possess mechanisms to manipulate the host cell, typically through a specialized secretion system which crosses the vacuole membrane. While there are common themes, each bacterial pathogen utilizes unique approach to establishing and maintaining their intracellular niches. In this review, we focus on the vacuole-bound intracellular niches of Anaplasma phagocytophilum, Ehrlichia chaffeensis, Chlamydia trachomatis, and Coxiella burnetii.
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Affiliation(s)
| | | | - Stacey D. Gilk
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, United States
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5
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Ogen-Shtern N, Chang C, Saad H, Mazkereth N, Patel C, Shenkman M, Lederkremer GZ. COP I and II dependent trafficking controls ER-associated degradation in mammalian cells. iScience 2023; 26:106232. [PMID: 36876137 PMCID: PMC9982306 DOI: 10.1016/j.isci.2023.106232] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 01/09/2023] [Accepted: 02/14/2023] [Indexed: 02/22/2023] Open
Abstract
Misfolded proteins and components of the endoplasmic reticulum (ER) quality control and ER associated degradation (ERAD) machineries concentrate in mammalian cells in the pericentriolar ER-derived quality control compartment (ERQC), suggesting it as a staging ground for ERAD. By tracking the chaperone calreticulin and an ERAD substrate, we have now determined that the trafficking to the ERQC is reversible and recycling back to the ER is slower than the movement in the ER periphery. The dynamics suggest vesicular trafficking rather than diffusion. Indeed, using dominant negative mutants of ARF1 and Sar1 or the drugs Brefeldin A and H89, we observed that COPI inhibition causes accumulation in the ERQC and increases ERAD, whereas COPII inhibition has the opposite effect. Our results suggest that targeting of misfolded proteins to ERAD involves COPII-dependent transport to the ERQC and that they can be retrieved to the peripheral ER in a COPI-dependent manner.
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Affiliation(s)
- Navit Ogen-Shtern
- The Shmunis School of Biomedicine and Cancer Research, Cell Biology Division, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Chieh Chang
- The Shmunis School of Biomedicine and Cancer Research, Cell Biology Division, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Haddas Saad
- The Shmunis School of Biomedicine and Cancer Research, Cell Biology Division, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Niv Mazkereth
- The Shmunis School of Biomedicine and Cancer Research, Cell Biology Division, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Chaitanya Patel
- The Shmunis School of Biomedicine and Cancer Research, Cell Biology Division, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Marina Shenkman
- The Shmunis School of Biomedicine and Cancer Research, Cell Biology Division, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Gerardo Z Lederkremer
- The Shmunis School of Biomedicine and Cancer Research, Cell Biology Division, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
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6
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Jani RA, Di Cicco A, Keren-Kaplan T, Vale-Costa S, Hamaoui D, Hurbain I, Tsai FC, Di Marco M, Macé AS, Zhu Y, Amorim MJ, Bassereau P, Bonifacino JS, Subtil A, Marks MS, Lévy D, Raposo G, Delevoye C. PI4P and BLOC-1 remodel endosomal membranes into tubules. J Biophys Biochem Cytol 2022; 221:213508. [PMID: 36169638 PMCID: PMC9524204 DOI: 10.1083/jcb.202110132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 07/25/2022] [Accepted: 08/31/2022] [Indexed: 12/11/2022] Open
Abstract
Intracellular trafficking is mediated by transport carriers that originate by membrane remodeling from donor organelles. Tubular carriers contribute to the flux of membrane lipids and proteins to acceptor organelles, but how lipids and proteins impose a tubular geometry on the carriers is incompletely understood. Using imaging approaches on cells and in vitro membrane systems, we show that phosphatidylinositol-4-phosphate (PI4P) and biogenesis of lysosome-related organelles complex 1 (BLOC-1) govern the formation, stability, and functions of recycling endosomal tubules. In vitro, BLOC-1 binds and tubulates negatively charged membranes, including those containing PI4P. In cells, endosomal PI4P production by type II PI4-kinases is needed to form and stabilize BLOC-1-dependent recycling endosomal tubules. Decreased PI4KIIs expression impairs the recycling of endosomal cargoes and the life cycles of intracellular pathogens such as Chlamydia bacteria and influenza virus that exploit the membrane dynamics of recycling endosomes. This study demonstrates how a phospholipid and a protein complex coordinate the remodeling of cellular membranes into functional tubules.
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Affiliation(s)
- Riddhi Atul Jani
- Institut Curie, Université PSL, CNRS, UMR144, Structure and Membrane Compartments, Paris, France
| | - Aurélie Di Cicco
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physico-Chimie Curie, Paris, France.,Institut Curie, Université PSL, CNRS, UMR144, Cell and Tissue Imaging Facility (PICT-IBiSA), Paris, France
| | - Tal Keren-Kaplan
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD
| | - Silvia Vale-Costa
- Cell Biology of Viral Infection Lab, Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - Daniel Hamaoui
- Institut Pasteur, Université de Paris Cité, CNRS UMR3691, Cellular biology of microbial infection, Paris, France
| | - Ilse Hurbain
- Institut Curie, Université PSL, CNRS, UMR144, Structure and Membrane Compartments, Paris, France.,Institut Curie, Université PSL, CNRS, UMR144, Cell and Tissue Imaging Facility (PICT-IBiSA), Paris, France
| | - Feng-Ching Tsai
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physico-Chimie Curie, Paris, France
| | - Mathilde Di Marco
- Institut Curie, Université PSL, CNRS, UMR144, Structure and Membrane Compartments, Paris, France
| | - Anne-Sophie Macé
- Institut Curie, Université PSL, CNRS, UMR144, Cell and Tissue Imaging Facility (PICT-IBiSA), Paris, France
| | - Yueyao Zhu
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA.,Department of Biology, University of Pennsylvania, Philadelphia, PA
| | - Maria João Amorim
- Cell Biology of Viral Infection Lab, Instituto Gulbenkian de Ciência, Oeiras, Portugal.,Universidade Católica Portuguesa, Católica Medical School, Católica Biomedical Research Centre, Palma de Cima, Lisboa, Portugal
| | - Patricia Bassereau
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physico-Chimie Curie, Paris, France
| | - Juan S Bonifacino
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD
| | - Agathe Subtil
- Institut Pasteur, Université de Paris Cité, CNRS UMR3691, Cellular biology of microbial infection, Paris, France
| | - Michael S Marks
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA.,Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA.,Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Daniel Lévy
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physico-Chimie Curie, Paris, France.,Institut Curie, Université PSL, CNRS, UMR144, Cell and Tissue Imaging Facility (PICT-IBiSA), Paris, France
| | - Graça Raposo
- Institut Curie, Université PSL, CNRS, UMR144, Structure and Membrane Compartments, Paris, France.,Institut Curie, Université PSL, CNRS, UMR144, Cell and Tissue Imaging Facility (PICT-IBiSA), Paris, France
| | - Cédric Delevoye
- Institut Curie, Université PSL, CNRS, UMR144, Structure and Membrane Compartments, Paris, France.,Institut Curie, Université PSL, CNRS, UMR144, Cell and Tissue Imaging Facility (PICT-IBiSA), Paris, France
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7
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Vaughn B, Abu Kwaik Y. Idiosyncratic Biogenesis of Intracellular Pathogens-Containing Vacuoles. Front Cell Infect Microbiol 2021; 11:722433. [PMID: 34858868 PMCID: PMC8632064 DOI: 10.3389/fcimb.2021.722433] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 10/25/2021] [Indexed: 12/12/2022] Open
Abstract
While most bacterial species taken up by macrophages are degraded through processing of the bacteria-containing vacuole through the endosomal-lysosomal degradation pathway, intravacuolar pathogens have evolved to evade degradation through the endosomal-lysosomal pathway. All intra-vacuolar pathogens possess specialized secretion systems (T3SS-T7SS) that inject effector proteins into the host cell cytosol to modulate myriad of host cell processes and remodel their vacuoles into proliferative niches. Although intravacuolar pathogens utilize similar secretion systems to interfere with their vacuole biogenesis, each pathogen has evolved a unique toolbox of protein effectors injected into the host cell to interact with, and modulate, distinct host cell targets. Thus, intravacuolar pathogens have evolved clear idiosyncrasies in their interference with their vacuole biogenesis to generate a unique intravacuolar niche suitable for their own proliferation. While there has been a quantum leap in our knowledge of modulation of phagosome biogenesis by intravacuolar pathogens, the detailed biochemical and cellular processes affected remain to be deciphered. Here we discuss how the intravacuolar bacterial pathogens Salmonella, Chlamydia, Mycobacteria, Legionella, Brucella, Coxiella, and Anaplasma utilize their unique set of effectors injected into the host cell to interfere with endocytic, exocytic, and ER-to-Golgi vesicle traffic. However, Coxiella is the main exception for a bacterial pathogen that proliferates within the hydrolytic lysosomal compartment, but its T4SS is essential for adaptation and proliferation within the lysosomal-like vacuole.
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Affiliation(s)
- Bethany Vaughn
- Department of Microbiology and Immunology, University of Louisville, Louisville, KY, United States
| | - Yousef Abu Kwaik
- Department of Microbiology and Immunology, University of Louisville, Louisville, KY, United States.,Center for Predictive Medicine, College of Medicine, University of Louisville, Louisville, KY, United States
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8
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Enterovirus Infection Induces Massive Recruitment of All Isoforms of Small Cellular Arf GTPases to the Replication Organelles. J Virol 2020; 95:JVI.01629-20. [PMID: 33087467 DOI: 10.1128/jvi.01629-20] [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: 08/14/2020] [Accepted: 10/18/2020] [Indexed: 12/12/2022] Open
Abstract
Enterovirus replication requires the cellular protein GBF1, a guanine nucleotide exchange factor for small Arf GTPases. When activated, Arfs associate with membranes, where they regulate numerous steps of membrane homeostasis. The requirement for GBF1 implies that Arfs are important for replication, but which of the different Arfs function(s) during replication remains poorly understood. Here, we established cell lines expressing each of the human Arfs fused to a fluorescent tag and investigated their behavior during enterovirus infection. Arf1 was the first to be recruited to the replication organelles, where it strongly colocalized with the viral antigen 2B and mature virions but not double-stranded RNA. By the end of the infectious cycle, Arf3, Arf4, Arf5, and Arf6 were also concentrated on the replication organelles. Once on the replication membranes, all Arfs except Arf3 were no longer sensitive to inhibition of GBF1, suggesting that in infected cells they do not actively cycle between GTP- and GDP-bound states. Only the depletion of Arf1, but not other class 1 and 2 Arfs, significantly increased the sensitivity of replication to GBF1 inhibition. Surprisingly, depletion of Arf6, a class 3 Arf, normally implicated in plasma membrane events, also increased the sensitivity to GBF1 inhibition. Together, our results suggest that GBF1-dependent Arf1 activation directly supports the development and/or functioning of the replication complexes and that Arf6 plays a previously unappreciated role in viral replication. Our data reveal a complex pattern of Arf activation in enterovirus-infected cells that may contribute to the resilience of viral replication in different cellular environments.IMPORTANCE Enteroviruses include many known and emerging pathogens, such as poliovirus, enteroviruses 71 and D68, and others. However, licensed vaccines are available only against poliovirus and enterovirus 71, and specific anti-enterovirus therapeutics are lacking. Enterovirus infection induces the massive remodeling of intracellular membranes and the development of specialized domains harboring viral replication complexes, replication organelles. Here, we investigated the roles of small Arf GTPases during enterovirus infection. Arfs control distinct steps in intracellular membrane traffic, and one of the Arf-activating proteins, GBF1, is a cellular factor required for enterovirus replication. We found that all Arfs expressed in human cells, including Arf6, normally associated with the plasma membrane, are recruited to the replication organelles and that Arf1 appears to be the most important Arf for enterovirus replication. These results document the rewiring of the cellular membrane pathways in infected cells and may provide new ways of controlling enterovirus infections.
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9
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Hijacking and Use of Host Kinases by Chlamydiae. Pathogens 2020; 9:pathogens9121034. [PMID: 33321710 PMCID: PMC7763869 DOI: 10.3390/pathogens9121034] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 12/01/2020] [Accepted: 12/07/2020] [Indexed: 12/11/2022] Open
Abstract
Chlamydia species are causative agents of sexually transmitted infections, blinding trachoma, and animal infections with zoonotic potential. Being an obligate intracellular pathogen, Chlamydia relies on the host cell for its survival and development, subverting various host cell processes throughout the infection cycle. A key subset of host proteins utilized by Chlamydia include an assortment of host kinase signaling networks which are vital for many chlamydial processes including entry, nutrient acquisition, and suppression of host cell apoptosis. In this review, we summarize the recent advancements in our understanding of host kinase subversion by Chlamydia.
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10
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Zhang H, Zhou J, Xiao P, Lin Y, Gong X, Liu S, Xu Q, Wang M, Ren H, Lu M, Wang Y, Zhu J, Xie Z, Li H, Lu K. PtdIns4P restriction by hydrolase SAC1 decides specific fusion of autophagosomes with lysosomes. Autophagy 2020; 17:1907-1917. [PMID: 32693712 DOI: 10.1080/15548627.2020.1796321] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Biogenesis of autophagosomes is the early step of macroautophagy/autophagy and requires membrane acquisition mainly from ER-Golgi-sourced precursor vesicles. Matured autophagosomes fuse with lysosomes for final degradation. However, how this selective fusion is determined remains elusive. Here, we identified Sac1 by a high throughput screen in Saccharomyces cerevisiae to show it was critical for autophagosome-lysosome fusion through its PtdIns4P phosphatase activity. Sac1 deficiency caused a dramatic increase of PtdIns4P at early Golgi apparatus and abnormal incorporation of PtdIns4P into Atg9 vesicles and autophagosomes, which caused failure to recruit SNARE proteins for autophagosome fusion with vacuoles. Sac1 function in autophagy was highly conserved from yeast to mammalian cells. Our work thus suggested that correct upstream lipid incorporation was important for downstream fusion step of autophagy and that Sac1 played a critical and ancient role in this surveillance of lipid integration.Abbreviations: Ape1: aminopeptidase Ι; ATG: autophagy related; EBSS: Earle's balanced salt solution; ER: endoplasmic reticulum; ERGIC: Golgi apparatus and ER-Golgi intermediate compartment; HOPS: homotypic fusion and protein sorting complex; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; PtdIns3P: phosphatidylinositol-3-phosphate; PtdIns4K: phosphoinositide-4-kinase; PtdIns4P: phosphatidylinositol-4-phosphate; SD-N: nitrogen starvation medium; SNARE: soluble N-ethylamide-sensitive factor attachment protein receptor.
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Affiliation(s)
- Hongjun Zhang
- Department of Neurosurgery, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Jiao Zhou
- Department of Neurosurgery, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Peng Xiao
- Department of Neurology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Yong Lin
- Key Laboratory of Molecular Biology for Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Xin Gong
- Department of Respiratory, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Shiyan Liu
- Department of Neurosurgery, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Qingjia Xu
- Department of Neurosurgery, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Minjin Wang
- Department of Clinical Laboratory, West China Hospital, Sichuan University, Chengdu, China
| | - Haiyan Ren
- Department of Respiratory, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Mengji Lu
- Institute of Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Yuan Wang
- Department of Neurology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Jing Zhu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Zhiping Xie
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Huihui Li
- West China Second University Hospital, Sichuan University, Chengdu, China
| | - Kefeng Lu
- Department of Neurosurgery, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
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11
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Colodette NM, Franco LS, Maia RC, Fokoue HH, Sant'Anna CMR, Barreiro EJ. Novel phosphatidylinositol 4-kinases III beta (PI4KIIIβ) inhibitors discovered by virtual screening using free energy models. J Comput Aided Mol Des 2020; 34:1091-1103. [PMID: 32601839 PMCID: PMC7324290 DOI: 10.1007/s10822-020-00327-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 06/17/2020] [Indexed: 12/19/2022]
Abstract
Herein, the LASSBio Chemical Library is presented as a valuable source of compounds for screening to identify hits suitable for subsequent hit-to-lead optimization stages. A feature of the LASSBio Chemical Library worth highlighting is the fact that it is a smart library designed by medicinal chemists with pharmacological activity as the main priority. The great majority of the compounds part of this library have shown in vivo activity in animal models, which is an indication that they possess overall favorable bioavailability properties and, hence, adequate pharmacokinetic profiles. This, in turn, is supported by the fact that approximately 85% of the compounds are compliant with Lipinski's rule of five and ca. 95% are compliant with Veber's rules, two important guidelines for oral bioavailability. In this work it is presented a virtual screening methodology combining a pharmacophore-based model and an empirical Gibbs free energy-based model for the ligand-protein interaction to explore the LASSBio Chemical Library as a source of new hits for the inhibition of the phosphatidylinositol 4-kinase IIIβ (PI4KIIIβ) enzyme, which is related to the development of viral infections (including enteroviruses, SARS coronavirus, and hepatitis C virus), cancers and neurological diseases. The approach resulted in the identification of two hits, LASSBio-1799 (7) and LASSBio-1814 (10), which inhibited the target enzyme with IC50 values of 3.66 μM and IC50 and 6.09 μM, respectively. This study also enabled the determination of the structural requirements for interactions with the active site of PI4KIIIβ, demonstrating the importance of both acceptor and donor hydrogen bonding groups for forming interactions with binding site residues Val598 and Lys549.
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Affiliation(s)
- Natalie M Colodette
- LASSBio - Laboratório de Avaliação e Síntese de Substâncias Bioativas, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, Avenida Carlos Chagas Filho 373, Rio de Janeiro, RJ, ZIP 21941-910, Brazil.,Programa de Pós-Graduação em Farmacologia e Química Medicinal, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, Rio de Janeiro, RJ, Brazil
| | - Lucas S Franco
- LASSBio - Laboratório de Avaliação e Síntese de Substâncias Bioativas, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, Avenida Carlos Chagas Filho 373, Rio de Janeiro, RJ, ZIP 21941-910, Brazil.,Programa de Pós-Graduação em Farmacologia e Química Medicinal, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, Rio de Janeiro, RJ, Brazil
| | - Rodolfo C Maia
- LASSBio - Laboratório de Avaliação e Síntese de Substâncias Bioativas, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, Avenida Carlos Chagas Filho 373, Rio de Janeiro, RJ, ZIP 21941-910, Brazil
| | - Harold H Fokoue
- LASSBio - Laboratório de Avaliação e Síntese de Substâncias Bioativas, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, Avenida Carlos Chagas Filho 373, Rio de Janeiro, RJ, ZIP 21941-910, Brazil
| | - Carlos Mauricio R Sant'Anna
- LASSBio - Laboratório de Avaliação e Síntese de Substâncias Bioativas, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, Avenida Carlos Chagas Filho 373, Rio de Janeiro, RJ, ZIP 21941-910, Brazil.,Departamento de Química Fundamental, Instituto de Química, Universidade Federal Rural do Rio de Janeiro, Rodovia BR465, km 7, Seropédica, RJ, ZIP 23897-000, Brazil
| | - Eliezer J Barreiro
- LASSBio - Laboratório de Avaliação e Síntese de Substâncias Bioativas, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, Avenida Carlos Chagas Filho 373, Rio de Janeiro, RJ, ZIP 21941-910, Brazil. .,Programa de Pós-Graduação em Farmacologia e Química Medicinal, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, Rio de Janeiro, RJ, Brazil. .,Programa de Pesquisas em Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, Rio de Janeiro, RJ, Brazil.
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12
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Faris R, Merling M, Andersen SE, Dooley CA, Hackstadt T, Weber MM. Chlamydia trachomatis CT229 Subverts Rab GTPase-Dependent CCV Trafficking Pathways to Promote Chlamydial Infection. Cell Rep 2020; 26:3380-3390.e5. [PMID: 30893609 DOI: 10.1016/j.celrep.2019.02.079] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 11/28/2018] [Accepted: 02/20/2019] [Indexed: 01/25/2023] Open
Abstract
Chlamydial infection requires the formation of a membrane-bound vacuole, termed the inclusion, that undergoes extensive interactions with select host organelles. The importance of the Inc protein CT229 in the formation and maintenance of the chlamydial inclusion was recently highlighted by studies demonstrating that its absence during infection results in reduced bacterial replication, premature inclusion lysis, and host cell death. Previous reports have indicated that CT229 binds Rab GTPases; however, the physiological implications of this interaction are unknown. Here, we show that CT229 regulates host multivesicular trafficking by recruiting multiple Rab GTPases and their cognate effectors to the inclusion. We demonstrate that CT229 specifically modulates clathrin-coated vesicle trafficking and regulates the trafficking of transferrin and the mannose-6-phosphate receptor, both of which are crucial for proper chlamydial development. This study highlights CT229 as a master regulator of multiple host vesicular trafficking pathways essential for chlamydial infection.
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Affiliation(s)
- Robert Faris
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, IA 52242, USA
| | - Marlena Merling
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, IA 52242, USA; Department of Biology, University of Dayton, Dayton, OH 45469, USA
| | - Shelby E Andersen
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, IA 52242, USA
| | - Cheryl A Dooley
- Host Parasite Interactions Section, Laboratory of Bacteriology, Rocky Mountain Laboratories, National Institutes of Allergy and Infectious Disease, NIH, Hamilton, MT 59840, USA
| | - Ted Hackstadt
- Host Parasite Interactions Section, Laboratory of Bacteriology, Rocky Mountain Laboratories, National Institutes of Allergy and Infectious Disease, NIH, Hamilton, MT 59840, USA
| | - Mary M Weber
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, IA 52242, USA.
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13
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Gitsels A, Sanders N, Vanrompay D. Chlamydial Infection From Outside to Inside. Front Microbiol 2019; 10:2329. [PMID: 31649655 PMCID: PMC6795091 DOI: 10.3389/fmicb.2019.02329] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 09/24/2019] [Indexed: 12/16/2022] Open
Abstract
Chlamydia are obligate intracellular bacteria, characterized by a unique biphasic developmental cycle. Specific interactions with the host cell are crucial for the bacteria’s survival and amplification because of the reduced chlamydial genome. At the start of infection, pathogen-host interactions are set in place in order for Chlamydia to enter the host cell and reach the nutrient-rich peri-Golgi region. Once intracellular localization is established, interactions with organelles and pathways of the host cell enable the necessary hijacking of host-derived nutrients. Detailed information on the aforementioned processes will increase our understanding on the intracellular pathogenesis of chlamydiae and hence might lead to new strategies to battle chlamydial infection. This review summarizes how chlamydiae generate their intracellular niche in the host cell, acquire host-derived nutrients in order to enable their growth and finally exit the host cell in order to infect new cells. Moreover, the evolution in the development of molecular genetic tools, necessary for studying the chlamydial infection biology in more depth, is discussed in great detail.
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Affiliation(s)
- Arlieke Gitsels
- Laboratory for Immunology and Animal Biotechnology, Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Niek Sanders
- Laboratory of Gene Therapy, Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Daisy Vanrompay
- Laboratory for Immunology and Animal Biotechnology, Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
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14
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Banhart S, Schäfer EK, Gensch JM, Heuer D. Sphingolipid Metabolism and Transport in Chlamydia trachomatis and Chlamydia psittaci Infections. Front Cell Dev Biol 2019; 7:223. [PMID: 31637241 PMCID: PMC6787139 DOI: 10.3389/fcell.2019.00223] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 09/20/2019] [Indexed: 12/05/2022] Open
Abstract
Chlamydia species infect a large range of vertebral hosts and have become of major economic and public health concern over the last decades. They are obligate intracellular bacteria that undergo a unique cycle of development characterized by the presence of two distinct bacterial forms. After infection of the host cell, Chlamydia are found inside a membrane-bound compartment, the inclusion. The surrounding membrane of the inclusion contributes to the host-Chlamydia interface and specific pathogen-derived Inc proteins shape this interface allowing interactions with distinct cellular proteins. In contrast to many other bacteria, Chlamydia species acquire sphingomyelin from the host cell. In recent years a clearer picture of how Chlamydia trachomatis acquires this lipid emerged showing that the bacteria interact with vesicular and non-vesicular transport pathways that involve the recruitment of specific RAB proteins and the lipid-transfer protein CERT. These interactions contribute to the development of a new sphingomyelin-producing compartment inside the host cell. Interestingly, recruitment of CERT is conserved among different Chlamydia species including Chlamydia psittaci. Here we discuss our current understanding on the molecular mechanisms used by C. trachomatis and C. psittaci to establish these interactions and to create a novel sphingomyelin-producing compartment inside the host cell important for the infection.
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Affiliation(s)
- Sebastian Banhart
- Unit 'Sexually Transmitted Bacterial Infections', Department for Infectious Diseases, Robert Koch Institute, Berlin, Germany
| | - Elena K Schäfer
- Unit 'Sexually Transmitted Bacterial Infections', Department for Infectious Diseases, Robert Koch Institute, Berlin, Germany
| | - Jean-Marc Gensch
- Unit 'Sexually Transmitted Bacterial Infections', Department for Infectious Diseases, Robert Koch Institute, Berlin, Germany
| | - Dagmar Heuer
- Unit 'Sexually Transmitted Bacterial Infections', Department for Infectious Diseases, Robert Koch Institute, Berlin, Germany
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15
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Abstract
In this article, we explore the unique adaptations of intracellular bacterial pathogens that manipulate conserved cellular pathways, organelles, and cargo to convert the phagosome into a pathogen-containing vacuole (PCV). The phagosome is a degradative organelle that rapidly acidifies as it delivers cargo to the lysosome to destroy microbes and cellular debris. However, to avoid this fate, intracellular bacterial pathogens hijack the key molecular modulators of intracellular traffic: small GTPases, phospholipids, SNAREs, and their associated effectors. Following uptake, pathogens that reside in the phagosome either remain associated with the endocytic pathway or rapidly diverge from the preprogrammed route to the lysosome. Both groups rely on effector-mediated mechanisms to meet the common challenges of intracellular life, such as nutrient acquisition, vacuole expansion, and evasion of the host immune response. Mycobacteria, Salmonella, and Coxiella serve as a lens through which we explore regulators of the canonical endocytic route and pathogens that seek to subvert it. On the other hand, pathogens such as Chlamydia, Legionella, and Brucella disconnect from the canonical endocytic route. This bifurcation is linked to extensive hijacking of the secretory pathway and repurposing of the PCV into specialized compartments that resemble organelles in the secretory network. Finally, each pathogen devises specific strategies to counteract host immune responses, such as autophagy, which aim to destroy these aberrant organelles. Collectively, each unique intracellular niche and the pathogens that construct them reflect the outcome of an aggressive and ongoing molecular arms race at the host-pathogen interface. Improving our understanding of these well-adapted pathogens can help us refine our knowledge of conserved cell biological processes.
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16
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NK Cell-Mediated Processing Of Chlamydia psittaci Drives Potent Anti-Bacterial Th1 Immunity. Sci Rep 2019; 9:4799. [PMID: 30886314 PMCID: PMC6423132 DOI: 10.1038/s41598-019-41264-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 03/05/2019] [Indexed: 11/08/2022] Open
Abstract
Natural killer (NK) cells are innate immune cells critically involved in the early immune response against various pathogens including chlamydia. Here, we demonstrate that chlamydia-infected NK cells prevent the intracellular establishment and growth of the bacteria. Upon infection, they display functional maturation characterized by enhanced IFN-γ secretion, CD146 induction, PKCϴ activation, and granule secretion. Eventually, chlamydia are released in a non-infectious, highly immunogenic form driving a potent Th1 immune response. Further, anti-chlamydial antibodies generated during immunization neutralize the infection of epithelial cells. The release of chlamydia from NK cells requires PKCϴ function and active degranulation, while granule-associated granzyme B drives the loss of chlamydial infectivity. Cellular infection and bacterial release can be undergone repeatedly and do not affect NK cell function. Strikingly, NK cells passing through such an infection cycle significantly improve their cytotoxicity. Thus, NK cells not only protect themselves against productive chlamydial infections but also actively trigger potent anti-bacterial responses.
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17
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Fernández-Oliva A, Ortega-González P, Risco C. Targeting host lipid flows: Exploring new antiviral and antibiotic strategies. Cell Microbiol 2019; 21:e12996. [PMID: 30585688 PMCID: PMC7162424 DOI: 10.1111/cmi.12996] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 12/04/2018] [Accepted: 12/17/2018] [Indexed: 12/28/2022]
Abstract
Bacteria and viruses pose serious challenges for humans because they evolve continuously. Despite ongoing efforts, antiviral drugs to treat many of the most troubling viruses have not been approved yet. The recent launch of new antimicrobials is generating hope as more and more pathogens around the world become resistant to available drugs. But extra effort is still needed. One of the current strategies for antiviral and antibiotic drug development is the search for host cellular pathways used by many different pathogens. For example, many viruses and bacteria alter lipid synthesis and transport to build their own organelles inside infected cells. The characterization of these interactions will be fundamental to identify new targets for antiviral and antibiotic drug development. This review discusses how viruses and bacteria subvert cell machineries for lipid synthesis and transport and summarises the most promising compounds that interfere with these pathways.
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Affiliation(s)
| | | | - Cristina Risco
- Cell Structure Lab, National Centre for Biotechnology, CNB-CSIC, Madrid, Spain
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18
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Martinez E, Siadous FA, Bonazzi M. Tiny architects: biogenesis of intracellular replicative niches by bacterial pathogens. FEMS Microbiol Rev 2018; 42:425-447. [PMID: 29596635 DOI: 10.1093/femsre/fuy013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 03/26/2018] [Indexed: 11/13/2022] Open
Abstract
Co-evolution of bacterial pathogens with their hosts led to the emergence of a stunning variety of strategies aiming at the evasion of host defences, colonisation of host cells and tissues and, ultimately, the establishment of a successful infection. Pathogenic bacteria are typically classified as extracellular and intracellular; however, intracellular lifestyle comes in many different flavours: some microbes rapidly escape to the cytosol whereas other microbes remain within vacuolar compartments and harness membrane trafficking pathways to generate their host-derived, pathogen-specific replicative niche. Here we review the current knowledge on a variety of vacuolar lifestyles, the effector proteins used by bacteria as tools to take control of the host cell and the main membrane trafficking signalling pathways targeted by vacuolar pathogens as source of membranes and nutrients. Finally, we will also discuss how host cells have developed countermeasures to sense the biogenesis of the aberrant organelles harbouring bacteria. Understanding the dialogue between bacterial and eukaryotic proteins is the key to unravel the molecular mechanisms of infection and in turn, this may lead to the identification of new targets for the development of new antimicrobials.
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Affiliation(s)
- Eric Martinez
- IRIM, University of Montpellier, CNRS, 34293 Montpellier, France
| | | | - Matteo Bonazzi
- IRIM, University of Montpellier, CNRS, 34293 Montpellier, France
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19
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Fischer A, Rudel T. Safe haven under constant attack-The Chlamydia-containing vacuole. Cell Microbiol 2018; 20:e12940. [PMID: 30101516 DOI: 10.1111/cmi.12940] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Revised: 07/24/2018] [Accepted: 07/31/2018] [Indexed: 11/30/2022]
Abstract
Chlamydia belong to the group of obligate intracellular bacteria that reside in a membrane bound vacuole during the entire intracellular phase of their life cycle. This vacuole called inclusion shields the bacteria from adverse influences in the cytosol of the host cell like the destructive machinery of the cell-autonomous defence system. The inclusion thereby prevents the digestion and eradication in specialised compartments of the intact and viable cell called phagolysosomes or autophagolysosomes. It is becoming more and more evident that keeping the inclusion intact also prevents the onset of cell intrinsic cell death programmes that are activated upon damage of the inclusion and direct the cell to destruct itself and the pathogen inside. Chlamydia secrete numerous proteins into the inclusion membrane to protect and stabilise their unique niche inside the host cell. We will focus in this review on the diverse attack strategies of the host aiming at the destruction of the Chlamydia-containing inclusion and will summarise the current knowledge on the protection mechanisms elaborated by the bacteria to maintain the integrity of their replication niche.
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Affiliation(s)
- Annette Fischer
- Department of Microbiology, University of Würzburg Biocenter, Würzburg, Germany
| | - Thomas Rudel
- Department of Microbiology, University of Würzburg Biocenter, Würzburg, Germany
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20
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Mackern-Oberti JP, Motrich RD, Damiani MT, Saka HA, Quintero CA, Sánchez LR, Moreno-Sosa T, Olivera C, Cuffini C, Rivero VE. Male genital tract immune response against Chlamydia trachomatis infection. Reproduction 2018; 154:R99-R110. [PMID: 28878094 DOI: 10.1530/rep-16-0561] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 07/01/2017] [Accepted: 07/11/2017] [Indexed: 01/01/2023]
Abstract
Chlamydia trachomatis is the most commonly reported agent of sexually transmitted bacterial infections worldwide. This pathogen frequently leads to persistent, long-term, subclinical infections, which in turn may cause severe pathology in susceptible hosts. This is in part due to the strategies that Chlamydia trachomatis uses to survive within epithelial cells and to evade the host immune response, such as subverting intracellular trafficking, interfering signaling pathways and preventing apoptosis. Innate immune receptors such as toll-like receptors expressed on epithelial and immune cells in the genital tract mediate the recognition of chlamydial molecular patterns. After bacterial recognition, a subset of pro-inflammatory cytokines and chemokines are continuously released by epithelial cells. The innate immune response is followed by the initiation of the adaptive response against Chlamydia trachomatis, which in turn may result in T helper 1-mediated protection or in T helper 2-mediated immunopathology. Understanding the molecular mechanisms developed by Chlamydia trachomatis to avoid killing and host immune response would be crucial for designing new therapeutic approaches and developing protective vaccines. In this review, we focus on chlamydial survival strategies and the elicited immune responses in male genital tract infections.
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Affiliation(s)
- Juan Pablo Mackern-Oberti
- Instituto de Medicina y Biología Experimental de Cuyo. IMBECU-CONICETMendoza, Argentina .,Instituto de Fisiología. Facultad de Ciencias MédicasUniversidad Nacional de Cuyo, Mendoza, Argentina
| | - Rubén Darío Motrich
- Centro de Investigaciones en Bioquímica Clínica e Inmunología CIBICI-CONICETDepartamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Maria Teresa Damiani
- Instituto de Histología y Embriología de Mendoza. IHEM-CONICETFacultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Héctor Alex Saka
- Centro de Investigaciones en Bioquímica Clínica e Inmunología CIBICI-CONICETDepartamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | | | - Leonardo Rodolfo Sánchez
- Centro de Investigaciones en Bioquímica Clínica e Inmunología CIBICI-CONICETDepartamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Tamara Moreno-Sosa
- Instituto de Medicina y Biología Experimental de Cuyo. IMBECU-CONICETMendoza, Argentina
| | - Carolina Olivera
- Centro de Investigaciones en Bioquímica Clínica e Inmunología CIBICI-CONICETDepartamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Cecilia Cuffini
- Instituto de Virología Dr. J. M. VanellaFacultad de Ciencias Médicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Virginia Elena Rivero
- Centro de Investigaciones en Bioquímica Clínica e Inmunología CIBICI-CONICETDepartamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
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21
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Banhart S, Rose L, Aeberhard L, Koch-Edelmann S, Heuer D. Chlamydia trachomatis and its interaction with the cellular retromer. Int J Med Microbiol 2017; 308:197-205. [PMID: 29122514 DOI: 10.1016/j.ijmm.2017.10.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 10/16/2017] [Accepted: 10/24/2017] [Indexed: 11/26/2022] Open
Abstract
Chlamydia trachomatis is an important human pathogen. This obligate intracellular bacterium grows inside the eukaryotic cell in a membrane-bound compartment, the inclusion. Recent global approaches describe the interactions of C. trachomatis with its host cell and indicate the inclusion is an intracellular trafficking hub embedded into the cellular vesicular trafficking pathways recruiting subunits of the retromer protein complex of the host cell. Here we review these recent developments in deciphering Chlamydia-host cell interactions with emphasis on the role of the retromer complex.
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Affiliation(s)
- Sebastian Banhart
- Division "Sexually Transmitted Bacterial Infections" (FG 19), Robert Koch Institute, Berlin, Germany
| | - Laura Rose
- Division "Sexually Transmitted Bacterial Infections" (FG 19), Robert Koch Institute, Berlin, Germany
| | - Lukas Aeberhard
- Division "Sexually Transmitted Bacterial Infections" (FG 19), Robert Koch Institute, Berlin, Germany
| | - Sophia Koch-Edelmann
- Division "Sexually Transmitted Bacterial Infections" (FG 19), Robert Koch Institute, Berlin, Germany
| | - Dagmar Heuer
- Division "Sexually Transmitted Bacterial Infections" (FG 19), Robert Koch Institute, Berlin, Germany.
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22
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Feldkamp ML, Ward DM, Pysher TJ, Chambers CT. Chlamydia trachomatis Is Responsible for Lipid Vacuolation in the Amniotic Epithelium of Fetal Gastroschisis. Birth Defects Res 2017. [PMID: 28635162 DOI: 10.1002/bdr2.1062] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Vacuolated amniotic epithelium with lipid droplets in gastroschisis placentas is an unusual finding. Mass spectrometry of lipid droplets identified triglycerides, ester-linked to an unusual pattern of fatty acids. We hypothesize that these findings result from a Chlamydia trachomatis infection during the periconceptional period. The rising incidence of chlamydia infections has paralleled the increasing prevalence of gastroschisis among women less than 25 years of age. Histologically, young women are at greatest risk for a chlamydia infection due to their immature columnar epithelium, the preferential site for attachment of Chlamydia trachomatis infectious particle (elementary body). METHODS Chlamydia trachomatis survive in an inclusion, relying on its host to acquire essential nutrients, amino acids, and nucleotides for survival and replication. If essential nutrients are not available, the bacteria cannot replicate and may be trafficked to the lysosome for degradation or remain quiescent, within the inclusion, subverting innate immunologic clearance. RESULTS Chlamydiae synthesize several lipids (phosphatidylethanolamine, phosphatidylserine, and phosphoatidylglycerol); however, their lipid content reveal eukaryotic lipids (sphingomyelin, cholesterol, phosphatidylcholine, and phosphatidylinositol), evidence that chlamydiae "hijack" host lipids for expansion and replication. CONCLUSION The abnormal amniotic epithelial findings are supported by experimental evidence of the trafficking of host lipids into the chlamydiae inclusion. If not lethal, what harm will elementary bodies inflict to the developing embryo? Do these women have a greater pro-inflammatory response to an environmental exposure, whether cigarette smoking, change in partner, or a pathogen? Testing the hypothesis that Chlamydia trachomatis is responsible for amniotic epithelium vacuoles will be a critical first step. Birth Defects Research 109:1003-1010, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Marcia L Feldkamp
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah
| | - Diane M Ward
- Division of Microbiology and Immunology, Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah
| | - Theodore J Pysher
- Division of Pediatric Pathology, Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah
| | - Christina T Chambers
- Division of Dysmorphology and Teratology, Department of Pediatrics, University of California San Diego, San Diego, California
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Abstract
Intracellular bacterial pathogens have evolved to exploit the protected niche provided within the boundaries of a eukaryotic host cell. Upon entering a host cell, some bacteria can evade the adaptive immune response of its host and replicate in a relatively nutrient-rich environment devoid of competition from other host flora. Growth within a host cell is not without their hazards, however. Many pathogens enter their hosts through receptor-mediated endocytosis or phagocytosis, two intracellular trafficking pathways that terminate in a highly degradative organelle, the phagolysosome. This usually deadly compartment is maintained at a low pH and contains degradative enzymes and reactive oxygen species, resulting in an environment to which few bacterial species are adapted. Some intracellular pathogens, such as Shigella, Listeria, Francisella, and Rickettsia, escape the phagosome to replicate within the cytosol of the host cell. Bacteria that remain within a vacuole either alter the trafficking of their initial phagosomal compartment or adapt to survive within the harsh environment it will soon become. In this chapter, we focus on the mechanisms by which different vacuolar pathogens either evade lysosomal fusion, as in the case of Mycobacterium and Chlamydia, or allow interaction with lysosomes to varying degrees, such as Brucella and Coxiella, and their specific adaptations to inhabit a replicative niche.
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Casey CA, Bhat G, Holzapfel MS, Petrosyan A. Study of Ethanol-Induced Golgi Disorganization Reveals the Potential Mechanism of Alcohol-Impaired N-Glycosylation. Alcohol Clin Exp Res 2016; 40:2573-2590. [PMID: 27748959 PMCID: PMC5133184 DOI: 10.1111/acer.13247] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 09/20/2016] [Indexed: 01/18/2023]
Abstract
BACKGROUND It is known that ethanol (EtOH) and its metabolites have a negative effect on protein glycosylation. The fragmentation of the Golgi apparatus induced by alteration of the structure of largest Golgi matrix protein, giantin, is the major consequence of damaging effects of EtOH-metabolism on the Golgi; however, the link between this and abnormal glycosylation remains unknown. Because previously we have shown that Golgi morphology dictates glycosylation, we examined the effect EtOH administration has on function of Golgi residential enzymes involved in N-glycosylation. METHODS HepG2 cells transfected with mouse ADH1 (VA-13 cells) were treated with 35 mM EtOH for 72 hours. Male Wistar rats were pair-fed Lieber-DeCarli diets for 5 to 8 weeks. Characterization of Golgi-associated mannosyl (α-1,3-)-glycoprotein beta-1,2-N-acetylglucosaminyltransferase (MGAT1), α-1,2-mannosidase (Man-I), and α-mannosidase II (Man-II) were performed in VA-13 cells and rat hepatocytes followed by three-dimensional structured illumination microscopy (3D SIM). RESULTS First, we detected that EtOH administration results in the loss of sialylated N-glycans on asialoglycoprotein receptor; however, the high-mannose-type N-glycans are increased. Further analysis by 3D SIM revealed that EtOH treatment despite Golgi disorganization does not change cis-Golgi localization for Man-I, but does induce medial-to-cis relocation of MGAT1 and Man-II. Using different approaches, including electron microscopy, we revealed that EtOH treatment results in dysfunction of ADP-ribosylation factor 1 (Arf1) GTPase followed by a deficiency in COPI vesicles at the Golgi. Silencing beta-COP or expression of GDP-bound mutant Arf1(T31N) mimics the EtOH effect on retaining MGAT1 and Man-II at the cis-Golgi, suggesting that (i) EtOH specifically blocks activation of Arf1, and (ii) EtOH alters the proper localization of Golgi enzymes through impairment of COPI. Importantly, the level of MGAT1 was reduced, because likely MGAT1, contrary to Man-I and Man-II, is giantin sensitive. CONCLUSIONS Thus, we provide the mechanism by which EtOH-induced Golgi remodeling may significantly modify formation of N-glycans.
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Affiliation(s)
- Carol A. Casey
- Department of Internal Medicine, University of Nebraska Medical Center, and the Fred and Pamela Buffett Cancer Center, Omaha, NE, USA
| | - Ganapati Bhat
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, and the Fred and Pamela Buffett Cancer Center, Omaha, NE, USA
| | - Melissa S. Holzapfel
- Department of Pathology and Microbiology, University of Nebraska Medical Center, and the Fred and Pamela Buffett Cancer Center, Omaha, NE, USA
| | - Armen Petrosyan
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, and the Fred and Pamela Buffett Cancer Center, Omaha, NE, USA
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Baumlova A, Gregor J, Boura E. The structural basis for calcium inhibition of lipid kinase PI4K IIalpha and comparison with the apo state. Physiol Res 2016; 65:987-993. [PMID: 27539108 DOI: 10.33549/physiolres.933344] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
PI4K IIalpha is a critical enzyme for the maintenance of Golgi and is also known to function in the synaptic vesicles. The product of its catalytical function, phosphatidylinositol 4-phosphate (PI4P), is an important lipid molecule because it is a hallmark of the Golgi and TGN, is directly recognized by many proteins and also serves as a precursor molecule for synthesis of higher phosphoinositides. Here, we report crystal structures of PI4K IIalpha enzyme in the apo-state and inhibited by calcium. The apo-structure reveals a surprising rigidity of the active site residues important for catalytic activity. The structure of calcium inhibited kinase reveals how calcium locks ATP in the active site.
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Affiliation(s)
- A Baumlova
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague, Czech Republic.
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26
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Abstract
Chlamydia spp. are important causes of human disease for which no effective vaccine exists. These obligate intracellular pathogens replicate in a specialized membrane compartment and use a large arsenal of secreted effectors to survive in the hostile intracellular environment of the host. In this Review, we summarize the progress in decoding the interactions between Chlamydia spp. and their hosts that has been made possible by recent technological advances in chlamydial proteomics and genetics. The field is now poised to decipher the molecular mechanisms that underlie the intimate interactions between Chlamydia spp. and their hosts, which will open up many exciting avenues of research for these medically important pathogens.
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Personnic N, Bärlocher K, Finsel I, Hilbi H. Subversion of Retrograde Trafficking by Translocated Pathogen Effectors. Trends Microbiol 2016; 24:450-462. [PMID: 26924068 DOI: 10.1016/j.tim.2016.02.003] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 01/22/2016] [Accepted: 02/01/2016] [Indexed: 12/22/2022]
Abstract
Intracellular bacterial pathogens subvert the endocytic bactericidal pathway to form specific replication-permissive compartments termed pathogen vacuoles or inclusions. To this end, the pathogens employ type III or type IV secretion systems, which translocate dozens, if not hundreds, of different effector proteins into their host cells, where they manipulate vesicle trafficking and signaling pathways in favor of the intruders. While the distinct cocktail of effectors defines the specific processes by which a pathogen vacuole is formed, the different pathogens commonly target certain vesicle trafficking routes, including the endocytic or secretory pathway. Recently, the retrograde transport pathway from endosomal compartments to the trans-Golgi network emerged as an important route affecting pathogen vacuole formation. Here, we review current insight into the host cell's retrograde trafficking pathway and how vacuolar pathogens of the genera Legionella, Coxiella, Salmonella, Chlamydia, and Simkania employ mechanistically distinct strategies to subvert this pathway, thus promoting intracellular survival and replication.
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Affiliation(s)
- Nicolas Personnic
- Institute of Medical Microbiology, Department of Medicine, University of Zürich, Gloriastrasse 30/32, 8006 Zürich, Switzerland
| | - Kevin Bärlocher
- Institute of Medical Microbiology, Department of Medicine, University of Zürich, Gloriastrasse 30/32, 8006 Zürich, Switzerland
| | - Ivo Finsel
- Max von Pettenkofer Institute, Ludwig-Maximilians University Munich, Pettenkoferstrasse 9a, 80336 Munich, Germany
| | - Hubert Hilbi
- Institute of Medical Microbiology, Department of Medicine, University of Zürich, Gloriastrasse 30/32, 8006 Zürich, Switzerland; Max von Pettenkofer Institute, Ludwig-Maximilians University Munich, Pettenkoferstrasse 9a, 80336 Munich, Germany.
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Quantitative Proteomics of the Infectious and Replicative Forms of Chlamydia trachomatis. PLoS One 2016; 11:e0149011. [PMID: 26871455 PMCID: PMC4752267 DOI: 10.1371/journal.pone.0149011] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 01/26/2016] [Indexed: 12/24/2022] Open
Abstract
The obligate intracellular developmental cycle of Chlamydia trachomatis presents significant challenges in defining its proteome. In this study we have applied quantitative proteomics to both the intracellular reticulate body (RB) and the extracellular elementary body (EB) from C. trachomatis. We used C. trachomatis L2 as a model chlamydial isolate for our study since it has a high infectivity:particle ratio and there is an excellent quality genome sequence. EBs and RBs (>99% pure) were quantified by chromosomal and plasmid copy number using PCR, from which the concentrations of chlamydial proteins per bacterial cell/genome were determined. RBs harvested at 15h post infection (PI) were purified by three successive rounds of gradient centrifugation. This is the earliest possible time to obtain purified RBs, free from host cell components in quantity, within the constraints of the technology. EBs were purified at 48h PI. We then used two-dimensional reverse phase UPLC to fractionate RB or EB peptides before mass spectroscopic analysis, providing absolute amount estimates of chlamydial proteins. The ability to express the data as molecules per cell gave ranking in both abundance and energy requirements for synthesis, allowing meaningful identification of rate-limiting components. The study assigned 562 proteins with high confidence and provided absolute estimates of protein concentration for 489 proteins. Interestingly, the data showed an increase in TTS capacity at 15h PI. Most of the enzymes involved in peptidoglycan biosynthesis were detected along with high levels of muramidase (in EBs) suggesting breakdown of peptidoglycan occurs in the non-dividing form of the microorganism. All the genome-encoded enzymes for glycolysis, pentose phosphate pathway and tricarboxylic acid cycle were identified and quantified; these data supported the observation that the EB is metabolically active. The availability of detailed, accurate quantitative proteomic data will be invaluable for investigations into gene regulation and function.
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29
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Toledo A, Benach JL. Hijacking and Use of Host Lipids by Intracellular Pathogens. Microbiol Spectr 2015; 3:10.1128/microbiolspec.VMBF-0001-2014. [PMID: 27337282 PMCID: PMC5790186 DOI: 10.1128/microbiolspec.vmbf-0001-2014] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Indexed: 12/14/2022] Open
Abstract
Intracellular bacteria use a number of strategies to survive, grow, multiply, and disseminate within the host. One of the most striking adaptations that intracellular pathogens have developed is the ability to utilize host lipids and their metabolism. Bacteria such as Anaplasma, Chlamydia, or Mycobacterium can use host lipids for different purposes, such as a means of entry through lipid rafts, building blocks for bacteria membrane formation, energy sources, camouflage to avoid the fusion of phagosomes and lysosomes, and dissemination. One of the most extreme examples of lipid exploitation is Mycobacterium, which not only utilizes the host lipid as a carbon and energy source but is also able to reprogram the host lipid metabolism. Likewise, Chlamydia spp. have also developed numerous mechanisms to reprogram lipids onto their intracellular inclusions. Finally, while the ability to exploit host lipids is important in intracellular bacteria, it is not an exclusive trait. Extracellular pathogens, including Helicobacter, Mycoplasma, and Borrelia, can recruit and metabolize host lipids that are important for their growth and survival.Throughout this chapter we will review how intracellular and extracellular bacterial pathogens utilize host lipids to enter, survive, multiply, and disseminate in the host.
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Affiliation(s)
- Alvaro Toledo
- Department of Molecular Genetics and Microbiology, Stony Brook University, Center for Infectious Diseases at the Center for Molecular Medicine, Stony Brook, NY 11794
| | - Jorge L Benach
- Department of Molecular Genetics and Microbiology, Stony Brook University, Center for Infectious Diseases at the Center for Molecular Medicine, Stony Brook, NY 11794
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Targeting of host organelles by pathogenic bacteria: a sophisticated subversion strategy. Nat Rev Microbiol 2015; 14:5-19. [PMID: 26594043 DOI: 10.1038/nrmicro.2015.1] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Many bacterial pathogens have evolved the ability to subvert and exploit host functions in order to enter and replicate in eukaryotic cells. For example, bacteria have developed specific mechanisms to target eukaryotic organelles such as the nucleus, the mitochondria, the endoplasmic reticulum and the Golgi apparatus. In this Review, we highlight the most recent advances in our understanding of the mechanisms that bacterial pathogens use to target these organelles. We also discuss how these strategies allow bacteria to manipulate host functions and to ultimately enable bacterial infection.
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31
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Boura E, Nencka R. Phosphatidylinositol 4-kinases: Function, structure, and inhibition. Exp Cell Res 2015; 337:136-45. [DOI: 10.1016/j.yexcr.2015.03.028] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 03/12/2015] [Indexed: 02/07/2023]
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Kokes M, Valdivia RH. Differential Translocation of Host Cellular Materials into the Chlamydia trachomatis Inclusion Lumen during Chemical Fixation. PLoS One 2015; 10:e0139153. [PMID: 26426122 PMCID: PMC4591358 DOI: 10.1371/journal.pone.0139153] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 09/08/2015] [Indexed: 11/19/2022] Open
Abstract
Chlamydia trachomatis manipulates host cellular pathways to ensure its proliferation and survival. Translocation of host materials into the pathogenic vacuole (termed 'inclusion') may facilitate nutrient acquisition and various organelles have been observed within the inclusion, including lipid droplets, peroxisomes, multivesicular body components, and membranes of the endoplasmic reticulum (ER). However, few of these processes have been documented in living cells. Here, we survey the localization of a broad panel of subcellular elements and find ER, mitochondria, and inclusion membranes within the inclusion lumen of fixed cells. However, we see little evidence of intraluminal localization of these organelles in live inclusions. Using time-lapse video microscopy we document ER marker translocation into the inclusion lumen during chemical fixation. These intra-inclusion ER elements resist a variety of post-fixation manipulations and are detectable via immunofluorescence microscopy. We speculate that the localization of a subset of organelles may be exaggerated during fixation. Finally, we find similar structures within the pathogenic vacuole of Coxiella burnetti infected cells, suggesting that fixation-induced translocation of cellular materials may occur into the vacuole of a range of intracellular pathogens.
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Affiliation(s)
- Marcela Kokes
- Department of Molecular Genetics and Microbiology and Center for the Genomics of Microbial Systems, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Raphael H. Valdivia
- Department of Molecular Genetics and Microbiology and Center for the Genomics of Microbial Systems, Duke University Medical Center, Durham, North Carolina, United States of America
- * E-mail:
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33
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Klima M, Baumlova A, Chalupska D, Hřebabecký H, Dejmek M, Nencka R, Boura E. The high-resolution crystal structure of phosphatidylinositol 4-kinase IIβ and the crystal structure of phosphatidylinositol 4-kinase IIα containing a nucleoside analogue provide a structural basis for isoform-specific inhibitor design. ACTA ACUST UNITED AC 2015; 71:1555-63. [PMID: 26143926 DOI: 10.1107/s1399004715009505] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 05/18/2015] [Indexed: 11/10/2022]
Abstract
Phosphatidylinositol 4-phosphate (PI4P) is the most abundant monophosphoinositide in eukaryotic cells. Humans have four phosphatidylinositol 4-kinases (PI4Ks) that synthesize PI4P, among which are PI4K IIβ and PI4K IIα. In this study, two crystal structures are presented: the structure of human PI4K IIβ and the structure of PI4K IIα containing a nucleoside analogue. The former, a complex with ATP, is the first high-resolution (1.9 Å) structure of a PI4K. These structures reveal new details such as high conformational heterogeneity of the lateral hydrophobic pocket of the C-lobe and together provide a structural basis for isoform-specific inhibitor design.
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Affiliation(s)
- Martin Klima
- Department of Biochemistry, Institute of Organic Chemistry and Biochemistry, Flemingovo nam. 2, 166 10 Prague, Czech Republic
| | - Adriana Baumlova
- Department of Biochemistry, Institute of Organic Chemistry and Biochemistry, Flemingovo nam. 2, 166 10 Prague, Czech Republic
| | - Dominika Chalupska
- Department of Biochemistry, Institute of Organic Chemistry and Biochemistry, Flemingovo nam. 2, 166 10 Prague, Czech Republic
| | - Hubert Hřebabecký
- Department of Biochemistry, Institute of Organic Chemistry and Biochemistry, Flemingovo nam. 2, 166 10 Prague, Czech Republic
| | - Milan Dejmek
- Department of Biochemistry, Institute of Organic Chemistry and Biochemistry, Flemingovo nam. 2, 166 10 Prague, Czech Republic
| | - Radim Nencka
- Department of Biochemistry, Institute of Organic Chemistry and Biochemistry, Flemingovo nam. 2, 166 10 Prague, Czech Republic
| | - Evzen Boura
- Department of Biochemistry, Institute of Organic Chemistry and Biochemistry, Flemingovo nam. 2, 166 10 Prague, Czech Republic
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34
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The Proteome of the Isolated Chlamydia trachomatis Containing Vacuole Reveals a Complex Trafficking Platform Enriched for Retromer Components. PLoS Pathog 2015; 11:e1004883. [PMID: 26042774 PMCID: PMC4456400 DOI: 10.1371/journal.ppat.1004883] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 04/14/2015] [Indexed: 12/22/2022] Open
Abstract
Chlamydia trachomatis is an important human pathogen that replicates inside the infected host cell in a unique vacuole, the inclusion. The formation of this intracellular bacterial niche is essential for productive Chlamydia infections. Despite its importance for Chlamydia biology, a holistic view on the protein composition of the inclusion, including its membrane, is currently missing. Here we describe the host cell-derived proteome of isolated C. trachomatis inclusions by quantitative proteomics. Computational analysis indicated that the inclusion is a complex intracellular trafficking platform that interacts with host cells’ antero- and retrograde trafficking pathways. Furthermore, the inclusion is highly enriched for sorting nexins of the SNX-BAR retromer, a complex essential for retrograde trafficking. Functional studies showed that in particular, SNX5 controls the C. trachomatis infection and that retrograde trafficking is essential for infectious progeny formation. In summary, these findings suggest that C. trachomatis hijacks retrograde pathways for effective infection. The important human pathogen Chlamydia trachomatis causes 100 million new infections each year world-wide. It replicates inside the infected host cell in a unique vacuole, the inclusion. Currently, the nature, and specifically the protein composition of the inclusion, is poorly defined. Here, we described the host cell-derived inclusion proteome by quantitative proteomics using a newly established method to purify inclusions from infected epithelial cells. We showed that the inclusion is a complex intracellular trafficking platform that is well embedded into the organellar network and interacts with host cells’ antero- and retrograde trafficking pathways. Particularly, SNX1, 2, 5 and 6, components of the retromer, are recruited to the inclusion and seem to control the infection. We found also that retrograde trafficking is essential for Chlamydia progeny formation. Our study provides new insights into how the obligate intracellular bacterium C. trachomatis interacts with the eukaryotic host cell and subverts host cell functions for productive infection.
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35
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Herweg JA, Hansmeier N, Otto A, Geffken AC, Subbarayal P, Prusty BK, Becher D, Hensel M, Schaible UE, Rudel T, Hilbi H. Purification and proteomics of pathogen-modified vacuoles and membranes. Front Cell Infect Microbiol 2015; 5:48. [PMID: 26082896 PMCID: PMC4451638 DOI: 10.3389/fcimb.2015.00048] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 05/14/2015] [Indexed: 01/08/2023] Open
Abstract
Certain pathogenic bacteria adopt an intracellular lifestyle and proliferate in eukaryotic host cells. The intracellular niche protects the bacteria from cellular and humoral components of the mammalian immune system, and at the same time, allows the bacteria to gain access to otherwise restricted nutrient sources. Yet, intracellular protection and access to nutrients comes with a price, i.e., the bacteria need to overcome cell-autonomous defense mechanisms, such as the bactericidal endocytic pathway. While a few bacteria rupture the early phagosome and escape into the host cytoplasm, most intracellular pathogens form a distinct, degradation-resistant and replication-permissive membranous compartment. Intracellular bacteria that form unique pathogen vacuoles include Legionella, Mycobacterium, Chlamydia, Simkania, and Salmonella species. In order to understand the formation of these pathogen niches on a global scale and in a comprehensive and quantitative manner, an inventory of compartment-associated host factors is required. To this end, the intact pathogen compartments need to be isolated, purified and biochemically characterized. Here, we review recent progress on the isolation and purification of pathogen-modified vacuoles and membranes, as well as their proteomic characterization by mass spectrometry and different validation approaches. These studies provide the basis for further investigations on the specific mechanisms of pathogen-driven compartment formation.
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Affiliation(s)
- Jo-Ana Herweg
- Chair of Microbiology, Biocenter, University of Würzburg Würzburg, Germany
| | - Nicole Hansmeier
- Division of Microbiology, University of Osnabrück Osnabrück, Germany
| | - Andreas Otto
- Institute of Microbiology, Ernst-Moritz-Arndt University Greifswald Greifswald, Germany
| | - Anna C Geffken
- Priority Area Infections, Cellular Microbiology, Research Center Borstel, Leibniz Center for Medicine and Biosciences Borstel, Germany
| | - Prema Subbarayal
- Chair of Microbiology, Biocenter, University of Würzburg Würzburg, Germany
| | - Bhupesh K Prusty
- Chair of Microbiology, Biocenter, University of Würzburg Würzburg, Germany
| | - Dörte Becher
- Institute of Microbiology, Ernst-Moritz-Arndt University Greifswald Greifswald, Germany
| | - Michael Hensel
- Division of Microbiology, University of Osnabrück Osnabrück, Germany
| | - Ulrich E Schaible
- Priority Area Infections, Cellular Microbiology, Research Center Borstel, Leibniz Center for Medicine and Biosciences Borstel, Germany
| | - Thomas Rudel
- Chair of Microbiology, Biocenter, University of Würzburg Würzburg, Germany
| | - Hubert Hilbi
- Department of Medicine, Max von Pettenkofer Institute, Ludwig-Maximilians University Munich Munich, Germany ; Department of Medicine, Institute of Medical Microbiology, University of Zürich Zürich, Switzerland
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The Chlamydia pneumoniae Inclusion Membrane Protein Cpn1027 Interacts with Host Cell Wnt Signaling Pathway Regulator Cytoplasmic Activation/Proliferation-Associated Protein 2 (Caprin2). PLoS One 2015; 10:e0127909. [PMID: 25996495 PMCID: PMC4440618 DOI: 10.1371/journal.pone.0127909] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 04/21/2015] [Indexed: 11/19/2022] Open
Abstract
We previously identified hypothetical protein Cpn1027 as a novel inclusion membrane protein that is unique to Chlamydia pneumoniae. In the current study, using a yeast-two hybrid screen assay, we identified host cell cytoplasmic activation/proliferation-associated protein 2 (Caprin2) as an interacting partner of Cpn1027. The interaction was confirmed and mapped to the C-termini of both Cpn1027 and Caprin2 using co-immunoprecipitation and GST pull-down assays. A RFP-Caprin2 fusion protein was recruited to the chlamydial inclusion and so was the endogenous GSK3β, a critical component of the β-catenin destruction complex in the Wnt signaling pathway. Cpn1027 also co-precipitated GSK3β. Caprin2 is a key regulator of the Wnt signaling pathway by promoting the recruitment of the β-catenin destruction complex to the cytoplasmic membrane in the presence of Wnt signaling while GSK3β is required for priming β-catenin for degradation in the absence of Wnt signaling. The Cpn1027 interactions with Caprin2 and GSK3β may allow C. pneumoniae to actively sequester the β-catenin destruction complex so that β-catenin is maintained even in the absence of extracellular Wnt activation signals. The maintained β-catenin can trans-activate Wnt target genes including Bcl-2, which may contribute to the chlamydial antiapoptotic activity. We found that the C. pneumoniae-infected cells were more resistant to apoptosis induction and the anti-apoptotic activity was dependent on β-catenin. Thus, the current study suggests that the chlamydial inclusion protein Cpn1027 may be able to manipulate host Wnt signaling pathway for enhancing the chlamydial anti-apoptotic activity.
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37
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Kokes M, Dunn JD, Granek JA, Nguyen BD, Barker JR, Valdivia RH, Bastidas RJ. Integrating chemical mutagenesis and whole-genome sequencing as a platform for forward and reverse genetic analysis of Chlamydia. Cell Host Microbe 2015; 17:716-25. [PMID: 25920978 DOI: 10.1016/j.chom.2015.03.014] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 02/11/2015] [Accepted: 03/17/2015] [Indexed: 11/18/2022]
Abstract
Gene inactivation by transposon insertion or allelic exchange is a powerful approach to probe gene function. Unfortunately, many microbes, including Chlamydia, are not amenable to routine molecular genetic manipulations. Here we describe an arrayed library of chemically induced mutants of the genetically intransigent pathogen Chlamydia trachomatis, in which all mutations have been identified by whole-genome sequencing, providing a platform for reverse genetic applications. An analysis of possible loss-of-function mutations in the collection uncovered plasticity in the central metabolic properties of this obligate intracellular pathogen. We also describe the use of the library in a forward genetic screen that identified InaC as a bacterial factor that binds host ARF and 14-3-3 proteins and modulates F-actin assembly and Golgi redistribution around the pathogenic vacuole. This work provides a robust platform for reverse and forward genetic approaches in Chlamydia and should serve as a valuable resource to the community.
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Affiliation(s)
- Marcela Kokes
- Department of Molecular Genetics and Microbiology and Center for the Genomics of Microbial Systems, Duke University Medical Center, 268 CARL Building, Box 3054, Durham, NC 27710, USA
| | - Joe Dan Dunn
- Department of Molecular Genetics and Microbiology and Center for the Genomics of Microbial Systems, Duke University Medical Center, 268 CARL Building, Box 3054, Durham, NC 27710, USA
| | - Joshua A Granek
- Department of Molecular Genetics and Microbiology and Center for the Genomics of Microbial Systems, Duke University Medical Center, 268 CARL Building, Box 3054, Durham, NC 27710, USA; Department of Biostatistics and Bioinformatics, Duke University Medical Center, 2424 Erwin Road, Suite 1102 Hock Plaza, Box 2721, Durham, NC 27710, USA
| | - Bidong D Nguyen
- Department of Molecular Genetics and Microbiology and Center for the Genomics of Microbial Systems, Duke University Medical Center, 268 CARL Building, Box 3054, Durham, NC 27710, USA
| | - Jeffrey R Barker
- Department of Molecular Genetics and Microbiology and Center for the Genomics of Microbial Systems, Duke University Medical Center, 268 CARL Building, Box 3054, Durham, NC 27710, USA
| | - Raphael H Valdivia
- Department of Molecular Genetics and Microbiology and Center for the Genomics of Microbial Systems, Duke University Medical Center, 268 CARL Building, Box 3054, Durham, NC 27710, USA.
| | - Robert J Bastidas
- Department of Molecular Genetics and Microbiology and Center for the Genomics of Microbial Systems, Duke University Medical Center, 268 CARL Building, Box 3054, Durham, NC 27710, USA.
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38
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Dumoux M, Nans A, Saibil HR, Hayward RD. Making connections: snapshots of chlamydial type III secretion systems in contact with host membranes. Curr Opin Microbiol 2014; 23:1-7. [PMID: 25461566 DOI: 10.1016/j.mib.2014.09.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 09/23/2014] [Accepted: 09/29/2014] [Indexed: 12/17/2022]
Abstract
Chlamydiae are obligate intracellular bacterial pathogens with an unusual biphasic lifecycle, which is underpinned by two bacterial forms of distinct structure and function. Bacterial entry and replication require a type III secretion system (T3SS), a widely conserved nanomachine responsible for the translocation of virulence effectors into host cells. Recent cell biology experiments supported by electron and cryo-electron tomography have provided fresh insights into Chlamydia-host interactions. In this review, we highlight some of the recent advances, particularly the in situ analysis of T3SSs in contact with host membranes during chlamydial entry and intracellular replication, and the role of the host rough endoplasmic reticulum (rER) at the recently described intracellular 'pathogen synapse'.
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Affiliation(s)
- Maud Dumoux
- Institute of Structural and Molecular Biology, University College London & Birkbeck, Malet Street, London WC1E 7HX, UK
| | - Andrea Nans
- Crystallography, Institute of Structural and Molecular Biology, Birkbeck College, University of London, Malet Street, London WC1E 7HX, UK
| | - Helen R Saibil
- Crystallography, Institute of Structural and Molecular Biology, Birkbeck College, University of London, Malet Street, London WC1E 7HX, UK
| | - Richard D Hayward
- Institute of Structural and Molecular Biology, University College London & Birkbeck, Malet Street, London WC1E 7HX, UK.
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39
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Asrat S, de Jesús DA, Hempstead AD, Ramabhadran V, Isberg RR. Bacterial Pathogen Manipulation of Host Membrane Trafficking. Annu Rev Cell Dev Biol 2014; 30:79-109. [DOI: 10.1146/annurev-cellbio-100913-013439] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Seblewongel Asrat
- Howard Hughes Medical Institute,
- Department of Molecular Biology and Microbiology, and
- Graduate Program in Molecular Microbiology, Sackler School of Graduate Biomedical Science, Tufts University School of Medicine, Boston, Massachusetts, 02111; , , , ,
| | - Dennise A. de Jesús
- Department of Molecular Biology and Microbiology, and
- Graduate Program in Molecular Microbiology, Sackler School of Graduate Biomedical Science, Tufts University School of Medicine, Boston, Massachusetts, 02111; , , , ,
| | - Andrew D. Hempstead
- Department of Molecular Biology and Microbiology, and
- Graduate Program in Molecular Microbiology, Sackler School of Graduate Biomedical Science, Tufts University School of Medicine, Boston, Massachusetts, 02111; , , , ,
| | - Vinay Ramabhadran
- Howard Hughes Medical Institute,
- Department of Molecular Biology and Microbiology, and
| | - Ralph R. Isberg
- Howard Hughes Medical Institute,
- Department of Molecular Biology and Microbiology, and
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40
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Septins arrange F-actin-containing fibers on the Chlamydia trachomatis inclusion and are required for normal release of the inclusion by extrusion. mBio 2014; 5:e01802-14. [PMID: 25293760 PMCID: PMC4196233 DOI: 10.1128/mbio.01802-14] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Chlamydia trachomatis is an obligate intracellular human pathogen that grows inside a membranous, cytosolic vacuole termed an inclusion. Septins are a group of 13 GTP-binding proteins that assemble into oligomeric complexes and that can form higher-order filaments. We report here that the septins SEPT2, -9, -11, and probably -7 form fibrillar structures around the chlamydial inclusion. Colocalization studies suggest that these septins combine with F actin into fibers that encase the inclusion. Targeting the expression of individual septins by RNA interference (RNAi) prevented the formation of septin fibers as well as the recruitment of actin to the inclusion. At the end of the developmental cycle of C. trachomatis, newly formed, infectious elementary bodies are released, and this release occurs at least in part through the organized extrusion of intact inclusions. RNAi against SEPT9 or against the combination of SEPT2/7/9 substantially reduced the number of extrusions from a culture of infected HeLa cells. The data suggest that a higher-order structure of four septins is involved in the recruitment or stabilization of the actin coat around the chlamydial inclusion and that this actin recruitment by septins is instrumental for the coordinated egress of C. trachomatis from human cells. The organization of F actin around parasite-containing vacuoles may be a broader response mechanism of mammalian cells to the infection by intracellular, vacuole-dwelling pathogens. Chlamydia trachomatis is a frequent bacterial pathogen throughout the world, causing mostly eye and genital infections. C. trachomatis can develop only inside host cells; it multiplies inside a membranous vacuole in the cytosol, termed an inclusion. The inclusion is covered by cytoskeletal “coats” or “cages,” whose organization and function are poorly understood. We here report that a relatively little-characterized group of proteins, septins, is required to organize actin fibers on the inclusion and probably through actin the release of the inclusion. Septins are a group of GTP-binding proteins that can organize into heteromeric complexes and then into large filaments. Septins have previously been found to be involved in the interaction of the cell with bacteria in the cytosol. Our observation that they also organize a reaction to bacteria living in vacuoles suggests that they have a function in the recognition of foreign compartments by a parasitized human cell.
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41
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Kabeiseman EJ, Cichos KH, Moore ER. The eukaryotic signal sequence, YGRL, targets the chlamydial inclusion. Front Cell Infect Microbiol 2014; 4:129. [PMID: 25309881 PMCID: PMC4161167 DOI: 10.3389/fcimb.2014.00129] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 08/28/2014] [Indexed: 11/13/2022] Open
Abstract
Understanding how host proteins are targeted to pathogen-specified organelles, like the chlamydial inclusion, is fundamentally important to understanding the biogenesis of these unique subcellular compartments and how they maintain autonomy within the cell. Syntaxin 6, which localizes to the chlamydial inclusion, contains an YGRL signal sequence. The YGRL functions to return syntaxin 6 to the trans-Golgi from the plasma membrane, and deletion of the YGRL signal sequence from syntaxin 6 also prevents the protein from localizing to the chlamydial inclusion. YGRL is one of three YXXL (YGRL, YQRL, and YKGL) signal sequences which target proteins to the trans-Golgi. We designed various constructs of eukaryotic proteins to test the specificity and propensity of YXXL sequences to target the inclusion. The YGRL signal sequence redirects proteins (e.g., Tgn38, furin, syntaxin 4) that normally do not localize to the chlamydial inclusion. Further, the requirement of the YGRL signal sequence for syntaxin 6 localization to inclusions formed by different species of Chlamydia is conserved. These data indicate that there is an inherent property of the chlamydial inclusion, which allows it to recognize the YGRL signal sequence. To examine whether this "inherent property" was protein or lipid in nature, we asked if deletion of the YGRL signal sequence from syntaxin 6 altered the ability of the protein to interact with proteins or lipids. Deletion or alteration of the YGRL from syntaxin 6 does not appreciably impact syntaxin 6-protein interactions, but does decrease syntaxin 6-lipid interactions. Intriguingly, data also demonstrate that YKGL or YQRL can successfully substitute for YGRL in localization of syntaxin 6 to the chlamydial inclusion. Importantly and for the first time, we are establishing that a eukaryotic signal sequence targets the chlamydial inclusion.
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Affiliation(s)
| | | | - Elizabeth R. Moore
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South DakotaVermillion, SD, USA
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42
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Mueller KE, Wolf K. C. pneumoniae disrupts eNOS trafficking and impairs NO production in human aortic endothelial cells. Cell Microbiol 2014; 17:119-30. [PMID: 25131610 DOI: 10.1111/cmi.12341] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 08/01/2014] [Accepted: 08/05/2014] [Indexed: 11/28/2022]
Abstract
Endothelial nitric oxide synthase (eNOS) generated NO plays a crucial physiological role in the regulation of vascular tone. eNOS is a constitutively expressed synthase whose enzymatic function is regulated by dual acylation, phosphorylation, protein-protein interaction and subcellular localization. In endothelial cells, the enzyme is primarily localized to the Golgi apparatus (GA) and the plasma membrane where it binds to caveolin-1. Upon stimulation, the enzyme is translocated from the plasma membrane to the cytoplasm where it generates NO. When activation of eNOS ceases, the majority of the enzyme is recycled back to the membrane fraction. An inability of eNOS to cycle between the cytosol and the membrane leads to impaired NO production and vascular dysfunction. Chlamydia pneumoniae is a Gram-negative obligate intracellular bacterium that primarily infects epithelial cells of the human respiratory tract, but unlike any other chlamydial species, C. pneumoniae displays tropism toward atherosclerotic tissues. In this study, we demonstrate that C. pneumoniae inclusions colocalize with eNOS, and the microorganism interferes with trafficking of the enzyme from the GA to the plasma membrane in primary human aortic endothelial cells. This mislocation of eNOS results in significant inhibition of NO release by C. pneumoniae-infected cells. Furthermore, we show that the distribution of eNOS in C. pneumoniae-infected cells is altered due to an intimate association of the Golgi complex with chlamydial inclusions rather than by direct interaction of the enzyme with the chlamydial inclusion membrane.
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Affiliation(s)
- Konrad E Mueller
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
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43
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Abstract
The specific interaction of phosphoinositides with proteins is critical for a plethora of cellular processes, including cytoskeleton remodelling, mitogenic signalling, ion channel regulation and membrane traffic. The spatiotemporal restriction of different phosphoinositide species helps to define compartments within the cell, and this is particularly important for membrane trafficking within both the secretory and endocytic pathways. Phosphoinositide homoeostasis is tightly regulated by a large number of inositol kinases and phosphatases, which respectively phosphorylate and dephosphorylate distinct phosphoinositide species. Many of these enzymes have been implicated in regulating membrane trafficking and, accordingly, their dysregulation has been linked to a number of human diseases. In the present review, we focus on the inositol phosphatases, concentrating on their roles in membrane trafficking and the human diseases with which they have been associated.
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Damiani MT, Gambarte Tudela J, Capmany A. Targeting eukaryotic Rab proteins: a smart strategy for chlamydial survival and replication. Cell Microbiol 2014; 16:1329-38. [PMID: 24948448 DOI: 10.1111/cmi.12325] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 06/13/2014] [Accepted: 06/16/2014] [Indexed: 02/04/2023]
Abstract
Chlamydia, an obligate intracellular bacterium which passes its entire lifecycle within a membrane-bound vacuole called the inclusion, has evolved a variety of unique strategies to establish an advantageous intracellular niche for survival. This review highlights the mechanisms by which Chlamydia subverts vesicular transport in host cells, particularly by hijacking the master controllers of eukaryotic trafficking, the Rab proteins. A subset of Rabs and Rab interacting proteins that control the recycling pathway or the biosynthetic route are selectively recruited to the chlamydial inclusion membrane. By interfering with Rab-controlled transport steps, this intracellular pathogen not only prevents its own degradation in the phagocytic pathway, but also creates a favourable intracellular environment for growth and replication. Chlamydia, a highly adapted and successful intracellular pathogen, has several redundant strategies to re-direct vesicles emerging from biosynthetic compartments that carry host molecules essential for bacterial development. Although current knowledge is limited, the latest findings have shed light on the role of Rab proteins in the course of chlamydial infections and could open novel opportunities for anti-chlamydial therapy.
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Affiliation(s)
- María Teresa Damiani
- Laboratory of Phagocytosis and Intracellular Trafficking, IHEM-CONICET, School of Medicine, University of Cuyo, Mendoza, Argentina
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Pirruccello M, Nandez R, Idevall-Hagren O, Alcazar-Roman A, Abriola L, Berwick SA, Lucast L, Morel D, De Camilli P. Identification of inhibitors of inositol 5-phosphatases through multiple screening strategies. ACS Chem Biol 2014; 9:1359-68. [PMID: 24742366 PMCID: PMC4076014 DOI: 10.1021/cb500161z] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
![]()
Phosphoinositides are low abundance
membrane phospholipids that
have key roles in signaling, membrane trafficking, and cytoskeletal
dynamics in all cells. Until recently, strategies for robust and quantitative
development of pharmacological tools for manipulating phosphoinositide
levels have focused selectively on PI(3,4,5)P3 due to the
importance of this lipid in growth factor signaling and cell proliferation.
However, drugs that affect levels of other phosphoinositides have
potential therapeutic applications and will be powerful research tools.
Here, we describe methodology for the high-throughput screening of
small molecule modulators of the inositol 5-phosphatases, which dephosphorylate
PI(4,5)P2 (the precursor for PI(3,4,5)P3) and
PI(3,4,5)P3). We developed three complementary in vitro activity assays, tested hit compounds on a panel
of 5-phosphatases, and monitored efficacy toward various substrates.
Two prominent chemical scaffolds were identified with high nanomolar/low
micromolar activity, with one class showing inhibitory activity toward
all 5-phosphatases tested and the other selective activity toward
OCRL and INPP5B, which are closely related to each other. One highly
soluble OCRL/INPP5B-specific inhibitor shows a direct interaction
with the catalytic domain of INPP5B. The efficacy of this compound
in living cells was validated through its property to enhance actin
nucleation at the cell cortex, a PI(4,5)P2 dependent process,
and to inhibit PI(4,5)P2 dephosphorylation by OCRL (both
overexpressed and endogenous enzyme). The assays and screening strategies
described here are applicable to other phosphoinositide-metabolizing
enzymes, at least several of which have major clinical relevance.
Most importantly, this study identifies the first OCRL/INPP5B specific
inhibitor and provides a platform for the design of more potent inhibitors
of this family of enzymes.
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Affiliation(s)
- Michelle Pirruccello
- Department
of Cell Biology, Howard Hughes Medical Institute and Program in Cellular
Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven Connecticut 06510, United States
| | - Ramiro Nandez
- Department
of Cell Biology, Howard Hughes Medical Institute and Program in Cellular
Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven Connecticut 06510, United States
| | - Olof Idevall-Hagren
- Department
of Cell Biology, Howard Hughes Medical Institute and Program in Cellular
Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven Connecticut 06510, United States
| | - Abel Alcazar-Roman
- Department
of Cell Biology, Howard Hughes Medical Institute and Program in Cellular
Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven Connecticut 06510, United States
| | - Laura Abriola
- Yale
Center for Molecular Discovery, Yale University, West Haven, Connecticut 06516, United States
| | - Shana Alexandra Berwick
- Department
of Cell Biology, Howard Hughes Medical Institute and Program in Cellular
Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven Connecticut 06510, United States
| | - Louise Lucast
- Department
of Cell Biology, Howard Hughes Medical Institute and Program in Cellular
Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven Connecticut 06510, United States
| | - Dayna Morel
- Department
of Cell Biology, Howard Hughes Medical Institute and Program in Cellular
Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven Connecticut 06510, United States
| | - Pietro De Camilli
- Department
of Cell Biology, Howard Hughes Medical Institute and Program in Cellular
Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven Connecticut 06510, United States
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Mehta ZB, Pietka G, Lowe M. The cellular and physiological functions of the Lowe syndrome protein OCRL1. Traffic 2014; 15:471-87. [PMID: 24499450 PMCID: PMC4278560 DOI: 10.1111/tra.12160] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 02/03/2014] [Accepted: 02/05/2014] [Indexed: 12/17/2022]
Abstract
Phosphoinositide lipids play a key role in cellular physiology, participating in a wide array of cellular processes. Consequently, mutation of phosphoinositide-metabolizing enzymes is responsible for a growing number of diseases in humans. Two related disorders, oculocerebrorenal syndrome of Lowe (OCRL) and Dent-2 disease, are caused by mutation of the inositol 5-phosphatase OCRL1. Here, we review recent advances in our understanding of OCRL1 function. OCRL1 appears to regulate many processes within the cell, most of which depend upon coordination of membrane dynamics with remodeling of the actin cytoskeleton. Recently developed animal models have managed to recapitulate features of Lowe syndrome and Dent-2 disease, and revealed new insights into the underlying mechanisms of these disorders. The continued use of both cell-based approaches and animal models will be key to fully unraveling OCRL1 function, how its loss leads to disease and, importantly, the development of therapeutics to treat patients.
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Affiliation(s)
- Zenobia B Mehta
- Faculty of Life Sciences, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK; Current address: Faculty of Medicine, Imperial College, London, UK
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Silmon de Monerri NC, Kim K. Pathogens hijack the epigenome: a new twist on host-pathogen interactions. THE AMERICAN JOURNAL OF PATHOLOGY 2014; 184:897-911. [PMID: 24525150 DOI: 10.1016/j.ajpath.2013.12.022] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 12/01/2013] [Accepted: 12/05/2013] [Indexed: 02/07/2023]
Abstract
Pathogens have evolved strategies to promote their survival by dramatically modifying the transcriptional profile and protein content of the host cells they infect. Modifications of the host transcriptome and proteome are mediated by pathogen-encoded effector molecules that modulate host cells through a variety of different mechanisms. Recent studies highlight the importance of the host chromatin and other epigenetic regulators as targets of pathogens. Host gene regulatory mechanisms may be targeted through cytoplasmic signaling, directly by pathogen effector proteins, and possibly by pathogen RNA. Although many of these changes are short-lived and persist only during the course of infection, several studies indicate that pathogens are able to induce long-term, heritable changes that are essential to pathogenesis of infectious diseases and persistence of pathogens within their hosts. In this review, we discuss how pathogens modulate the epigenome of host cells, a new and flourishing avenue of host-pathogen interaction studies.
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Affiliation(s)
- Natalie C Silmon de Monerri
- Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York
| | - Kami Kim
- Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York.
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48
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Mehlitz A, Rudel T. Modulation of host signaling and cellular responses by Chlamydia. Cell Commun Signal 2013; 11:90. [PMID: 24267514 PMCID: PMC4222901 DOI: 10.1186/1478-811x-11-90] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 11/19/2013] [Indexed: 01/24/2023] Open
Abstract
Modulation of host cell signaling and cellular functions is key to intracellular survival of pathogenic bacteria. Intracellular growth has several advantages e.g. escape from the humoral immune response and access to a stable nutrient rich environment. Growth in such a preferred niche comes at the price of an ongoing competition between the bacteria and the host as well as other microbes that compete for the very same host resources. This requires specialization and constant evolution of dedicated systems for adhesion, invasion and accommodation. Interestingly, obligate intracellular bacteria of the order Chlamydiales have evolved an impressive degree of control over several important host cell functions. In this review we summarize how Chlamydia controls its host cell with a special focus on signal transduction and cellular modulation.
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Affiliation(s)
- Adrian Mehlitz
- University of Wuerzburg, Biocenter, Department of Microbiology, Am Hubland, D-97074, Wuerzburg, Germany.
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49
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Tan J, Brill JA. Cinderella story: PI4P goes from precursor to key signaling molecule. Crit Rev Biochem Mol Biol 2013; 49:33-58. [PMID: 24219382 DOI: 10.3109/10409238.2013.853024] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Phosphatidylinositol lipids are signaling molecules involved in nearly all aspects of cellular regulation. Production of phosphatidylinositol 4-phosphate (PI4P) has long been recognized as one of the first steps in generating poly-phosphatidylinositol phosphates involved in actin organization, cell migration, and signal transduction. In addition, progress over the last decade has brought to light independent roles for PI4P in membrane trafficking and lipid homeostasis. Here, we describe recent advances that reveal the breadth of processes regulated by PI4P, the spectrum of PI4P effectors, and the mechanisms of spatiotemporal control that coordinate crosstalk between PI4P and cellular signaling pathways.
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Affiliation(s)
- Julie Tan
- Department of Molecular Genetics, University of Toronto , Toronto, Ontario , Canada and
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50
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Abstract
Phosphoinositides (PIs) make up only a small fraction of cellular phospholipids, yet they control almost all aspects of a cell's life and death. These lipids gained tremendous research interest as plasma membrane signaling molecules when discovered in the 1970s and 1980s. Research in the last 15 years has added a wide range of biological processes regulated by PIs, turning these lipids into one of the most universal signaling entities in eukaryotic cells. PIs control organelle biology by regulating vesicular trafficking, but they also modulate lipid distribution and metabolism via their close relationship with lipid transfer proteins. PIs regulate ion channels, pumps, and transporters and control both endocytic and exocytic processes. The nuclear phosphoinositides have grown from being an epiphenomenon to a research area of its own. As expected from such pleiotropic regulators, derangements of phosphoinositide metabolism are responsible for a number of human diseases ranging from rare genetic disorders to the most common ones such as cancer, obesity, and diabetes. Moreover, it is increasingly evident that a number of infectious agents hijack the PI regulatory systems of host cells for their intracellular movements, replication, and assembly. As a result, PI converting enzymes began to be noticed by pharmaceutical companies as potential therapeutic targets. This review is an attempt to give an overview of this enormous research field focusing on major developments in diverse areas of basic science linked to cellular physiology and disease.
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Affiliation(s)
- Tamas Balla
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA.
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