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Shtuhin-Rahav R, Olender A, Zlotkin-Rivkin E, Bouman EA, Danieli T, Nir-Keren Y, Weiss AM, Nandi I, Aroeti B. Enteropathogenic E. coli infection co-elicits lysosomal exocytosis and lytic host cell death. mBio 2023; 14:e0197923. [PMID: 38038448 PMCID: PMC10746156 DOI: 10.1128/mbio.01979-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 10/16/2023] [Indexed: 12/02/2023] Open
Abstract
IMPORTANCE Enteropathogenic Escherichia coli (EPEC) infection is a significant cause of gastroenteritis, mainly in children. Therefore, studying the mechanisms of EPEC infection is an important research theme. EPEC modulates its host cell life by injecting via a type III secretion machinery cell death modulating effector proteins. For instance, while EspF and Map promote mitochondrial cell death, EspZ antagonizes cell death. We show that these effectors also control lysosomal exocytosis, i.e., the trafficking of lysosomes to the host cell plasma membrane. Interestingly, the capacity of these effectors to induce or protect against cell death correlates completely with their ability to induce LE, suggesting that the two processes are interconnected. Modulating host cell death is critical for establishing bacterial attachment to the host and subsequent dissemination. Therefore, exploring the modes of LE involvement in host cell death is crucial for elucidating the mechanisms underlying EPEC infection and disease.
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Affiliation(s)
- Raisa Shtuhin-Rahav
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, The Edmond J. Safra Campus–Givat Ram, Jerusalem, Israel
- Department of Cell and Developmental Biology, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, The Edmond J. Safra Campus–Givat Ram, Jerusalem, Israel
| | - Aaron Olender
- Department of Cell and Developmental Biology, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, The Edmond J. Safra Campus–Givat Ram, Jerusalem, Israel
- The Alexander Grass Center for Bioengineering, The Hebrew University of Jerusalem, The Edmond J. Safra Campus–Givat Ram, Jerusalem, Israel
| | - Efrat Zlotkin-Rivkin
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, The Edmond J. Safra Campus–Givat Ram, Jerusalem, Israel
- Department of Cell and Developmental Biology, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, The Edmond J. Safra Campus–Givat Ram, Jerusalem, Israel
| | - Etan Amse Bouman
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, The Edmond J. Safra Campus–Givat Ram, Jerusalem, Israel
- Department of Cell and Developmental Biology, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, The Edmond J. Safra Campus–Givat Ram, Jerusalem, Israel
| | - Tsafi Danieli
- The Protein Production Facility, Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, The Edmond J. Safra Campus–Givat Ram, Jerusalem, Israel
| | - Yael Nir-Keren
- The Protein Production Facility, Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, The Edmond J. Safra Campus–Givat Ram, Jerusalem, Israel
| | - Aryeh M. Weiss
- Faculty of Engineering, Bar Ilan University, Ramat Gan, Israel
| | - Ipsita Nandi
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, The Edmond J. Safra Campus–Givat Ram, Jerusalem, Israel
- Department of Cell and Developmental Biology, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, The Edmond J. Safra Campus–Givat Ram, Jerusalem, Israel
| | - Benjamin Aroeti
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, The Edmond J. Safra Campus–Givat Ram, Jerusalem, Israel
- Department of Cell and Developmental Biology, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, The Edmond J. Safra Campus–Givat Ram, Jerusalem, Israel
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Valigurová A, Kolářová I. Unrevealing the Mystery of Latent Leishmaniasis: What Cells Can Host Leishmania? Pathogens 2023; 12:pathogens12020246. [PMID: 36839518 PMCID: PMC9967396 DOI: 10.3390/pathogens12020246] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Revised: 01/31/2023] [Accepted: 02/01/2023] [Indexed: 02/05/2023] Open
Abstract
Leishmania spp. (Kinetoplastida) are unicellular parasites causing leishmaniases, neglected tropical diseases of medical and veterinary importance. In the vertebrate host, Leishmania parasites multiply intracellularly in professional phagocytes, such as monocytes and macrophages. However, their close relative with intracellular development-Trypanosoma cruzi-can unlock even non-professional phagocytes. Since Leishmania and T. cruzi have similar organelle equipment, is it possible that Leishmania can invade and even proliferate in cells other than the professional phagocytes? Additionally, could these cells play a role in the long-term persistence of Leishmania in the host, even in cured individuals? In this review, we provide (i) an overview of non-canonical Leishmania host cells and (ii) an insight into the strategies that Leishmania may use to enter them. Many studies point to fibroblasts as already established host cells that are important in latent leishmaniasis and disease epidemiology, as they support Leishmania transformation into amastigotes and even their multiplication. To invade them, Leishmania causes damage to their plasma membrane and exploits the subsequent repair mechanism via lysosome-triggered endocytosis. Unrevealing the interactions between Leishmania and its non-canonical host cells may shed light on the persistence of these parasites in vertebrate hosts, a way to control latent leishmaniasis.
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Affiliation(s)
- Andrea Valigurová
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic
- Correspondence: (A.V.); (I.K.)
| | - Iva Kolářová
- Department of Parasitology, Faculty of Science, Charles University, Albertov 6, 128 44 Prague, Czech Republic
- Correspondence: (A.V.); (I.K.)
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3
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Apoptosis, Pyroptosis, and Necroptosis-Oh My! The Many Ways a Cell Can Die. J Mol Biol 2021; 434:167378. [PMID: 34838807 DOI: 10.1016/j.jmb.2021.167378] [Citation(s) in RCA: 122] [Impact Index Per Article: 40.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 11/12/2021] [Accepted: 11/21/2021] [Indexed: 12/12/2022]
Abstract
Cell death is an essential process in all living organisms and occurs through different mechanisms. The three main types of programmed cell death are apoptosis, pyroptosis, and necroptosis, and each of these pathways employs complex molecular and cellular mechanisms. Although there are mechanisms and outcomes specific to each pathway, they share common components and features. In this review, we discuss recent discoveries in these three best understood modes of cell death, highlighting their singularities, and examining the intriguing notion that common players shape different individual pathways in this highly interconnected and coordinated cell death system. Understanding the similarities and differences of these cell death processes is crucial to enable targeted strategies to manipulate these pathways for therapeutic benefit.
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Bertheloot D, Latz E, Franklin BS. Necroptosis, pyroptosis and apoptosis: an intricate game of cell death. Cell Mol Immunol 2021; 18:1106-1121. [PMID: 33785842 PMCID: PMC8008022 DOI: 10.1038/s41423-020-00630-3] [Citation(s) in RCA: 746] [Impact Index Per Article: 248.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 12/15/2020] [Indexed: 02/01/2023] Open
Abstract
Cell death is a fundamental physiological process in all living organisms. Its roles extend from embryonic development, organ maintenance, and aging to the coordination of immune responses and autoimmunity. In recent years, our understanding of the mechanisms orchestrating cellular death and its consequences on immunity and homeostasis has increased substantially. Different modalities of what has become known as 'programmed cell death' have been described, and some key players in these processes have been identified. We have learned more about the intricacies that fine tune the activity of common players and ultimately shape the different types of cell death. These studies have highlighted the complex mechanisms tipping the balance between different cell fates. Here, we summarize the latest discoveries in the three most well understood modalities of cell death, namely, apoptosis, necroptosis, and pyroptosis, highlighting common and unique pathways and their effect on the surrounding cells and the organism as a whole.
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Affiliation(s)
- Damien Bertheloot
- Institute of Innate Immunity, University Hospitals Bonn, University of Bonn, Bonn, NRW, Germany.
| | - Eicke Latz
- Institute of Innate Immunity, University Hospitals Bonn, University of Bonn, Bonn, NRW, Germany
- Department of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, USA
- German Center for Neurodegenerative Diseases, Bonn, NRW, Germany
| | - Bernardo S Franklin
- Institute of Innate Immunity, University Hospitals Bonn, University of Bonn, Bonn, NRW, Germany.
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5
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Trivedi PC, Bartlett JJ, Pulinilkunnil T. Lysosomal Biology and Function: Modern View of Cellular Debris Bin. Cells 2020; 9:cells9051131. [PMID: 32375321 PMCID: PMC7290337 DOI: 10.3390/cells9051131] [Citation(s) in RCA: 107] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 04/27/2020] [Accepted: 04/29/2020] [Indexed: 02/07/2023] Open
Abstract
Lysosomes are the main proteolytic compartments of mammalian cells comprising of a battery of hydrolases. Lysosomes dispose and recycle extracellular or intracellular macromolecules by fusing with endosomes or autophagosomes through specific waste clearance processes such as chaperone-mediated autophagy or microautophagy. The proteolytic end product is transported out of lysosomes via transporters or vesicular membrane trafficking. Recent studies have demonstrated lysosomes as a signaling node which sense, adapt and respond to changes in substrate metabolism to maintain cellular function. Lysosomal dysfunction not only influence pathways mediating membrane trafficking that culminate in the lysosome but also govern metabolic and signaling processes regulating protein sorting and targeting. In this review, we describe the current knowledge of lysosome in influencing sorting and nutrient signaling. We further present a mechanistic overview of intra-lysosomal processes, along with extra-lysosomal processes, governing lysosomal fusion and fission, exocytosis, positioning and membrane contact site formation. This review compiles existing knowledge in the field of lysosomal biology by describing various lysosomal events necessary to maintain cellular homeostasis facilitating development of therapies maintaining lysosomal function.
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Affiliation(s)
- Purvi C. Trivedi
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4H7, Canada; (P.C.T.); (J.J.B.)
- Dalhousie Medicine New Brunswick, Saint John, NB E2L 4L5, Canada
| | - Jordan J. Bartlett
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4H7, Canada; (P.C.T.); (J.J.B.)
- Dalhousie Medicine New Brunswick, Saint John, NB E2L 4L5, Canada
| | - Thomas Pulinilkunnil
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4H7, Canada; (P.C.T.); (J.J.B.)
- Dalhousie Medicine New Brunswick, Saint John, NB E2L 4L5, Canada
- Correspondence: ; Tel.: +1-(506)-636-6973
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6
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Cronemberger-Andrade A, Xander P, Soares RP, Pessoa NL, Campos MA, Ellis CC, Grajeda B, Ofir-Birin Y, Almeida IC, Regev-Rudzki N, Torrecilhas AC. Trypanosoma cruzi-Infected Human Macrophages Shed Proinflammatory Extracellular Vesicles That Enhance Host-Cell Invasion via Toll-Like Receptor 2. Front Cell Infect Microbiol 2020; 10:99. [PMID: 32266161 PMCID: PMC7098991 DOI: 10.3389/fcimb.2020.00099] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 02/26/2020] [Indexed: 12/14/2022] Open
Abstract
Extracellular vesicles (EVs) shed by trypomastigote forms of Trypanosoma cruzi have the ability to interact with host tissues, increase invasion, and modulate the host innate response. In this study, EVs shed from T. cruzi or T.cruzi-infected macrophages were investigated as immunomodulatory agents during the initial steps of infection. Initially, by scanning electron microscopy and nanoparticle tracking analysis, we determined that T. cruzi-infected macrophages release higher numbers of EVs (50-300 nm) as compared to non-infected cells. Using Toll-like-receptor 2 (TLR2)-transfected CHO cells, we observed that pre-incubation of these host cells with parasite-derived EVs led to an increase in the percentage of infected cells. In addition, EVs from parasite or T.cruzi-infected macrophages or not were able to elicit translocation of NF-κB by interacting with TLR2, and as a consequence, to alter the EVs the gene expression of proinflammatory cytokines (TNF-α, IL-6, and IL-1β), and STAT-1 and STAT-3 signaling pathways. By proteomic analysis, we observed highly significant changes in the protein composition between non-infected and infected host cell-derived EVs. Thus, we observed the potential of EVs derived from T. cruzi during infection to maintain the inflammatory response in the host.
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Affiliation(s)
| | - Patrícia Xander
- Departamento de Ciências Farmacêuticas, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
| | | | | | | | - Cameron C Ellis
- Border Biomedical Research Center, Department of Biological Sciences, University of Texas at El Paso (UTEP), El Paso, TX, United States
| | - Brian Grajeda
- Border Biomedical Research Center, Department of Biological Sciences, University of Texas at El Paso (UTEP), El Paso, TX, United States
| | - Yifat Ofir-Birin
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Igor Correia Almeida
- Border Biomedical Research Center, Department of Biological Sciences, University of Texas at El Paso (UTEP), El Paso, TX, United States
| | - Neta Regev-Rudzki
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Ana Claudia Torrecilhas
- Departamento de Ciências Farmacêuticas, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
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Mutvei AP, Nagiec MJ, Hamann JC, Kim SG, Vincent CT, Blenis J. Rap1-GTPases control mTORC1 activity by coordinating lysosome organization with amino acid availability. Nat Commun 2020; 11:1416. [PMID: 32184389 PMCID: PMC7078236 DOI: 10.1038/s41467-020-15156-5] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 02/17/2020] [Indexed: 02/08/2023] Open
Abstract
The kinase mTOR complex 1 (mTORC1) promotes cellular growth and is frequently dysregulated in cancers. In response to nutrients, mTORC1 is activated on lysosomes by Rag and Rheb guanosine triphosphatases (GTPases) and drives biosynthetic processes. How limitations in nutrients suppress mTORC1 activity remains poorly understood. We find that when amino acids are limited, the Rap1-GTPases confine lysosomes to the perinuclear region and reduce lysosome abundance, which suppresses mTORC1 signaling. Rap1 activation, which is independent of known amino acid signaling factors, limits the lysosomal surface available for mTORC1 activation. Conversely, Rap1 depletion expands the lysosome population, which markedly increases association between mTORC1 and its lysosome-borne activators, leading to mTORC1 hyperactivity. Taken together, we establish Rap1 as a critical coordinator of the lysosomal system, and propose that aberrant changes in lysosomal surface availability can impact mTORC1 signaling output.
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Affiliation(s)
- Anders P Mutvei
- Weill Cornell Medicine, Sandra and Edward Meyer Cancer Center, Belfer Research Building, 413 E. 69th St., New York, NY, 10021, USA.
- Karolinska Institutet, Department of Microbiology, Tumor and Cell biology, Nobels väg 16, KI Solna Campus Karolinska Institutet, Box 280, SE-171 77, Stockholm, Sweden.
- Department of Immunology, Genetics and Pathology, Uppsala University, Rudbeck Laboratory, 751 85, Uppsala, Sweden.
| | - Michal J Nagiec
- Weill Cornell Medicine, Sandra and Edward Meyer Cancer Center, Belfer Research Building, 413 E. 69th St., New York, NY, 10021, USA
| | - Jens C Hamann
- Weill Cornell Medicine, Sandra and Edward Meyer Cancer Center, Belfer Research Building, 413 E. 69th St., New York, NY, 10021, USA
| | - Sang Gyun Kim
- Weill Cornell Medicine, Sandra and Edward Meyer Cancer Center, Belfer Research Building, 413 E. 69th St., New York, NY, 10021, USA
| | - C Theresa Vincent
- Department of Immunology, Genetics and Pathology, Uppsala University, Rudbeck Laboratory, 751 85, Uppsala, Sweden
- Department of Microbiology, New York University School of Medicine, New York, NY, USA
| | - John Blenis
- Weill Cornell Medicine, Sandra and Edward Meyer Cancer Center, Belfer Research Building, 413 E. 69th St., New York, NY, 10021, USA.
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8
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Tanzer MC, Frauenstein A, Stafford CA, Phulphagar K, Mann M, Meissner F. Quantitative and Dynamic Catalogs of Proteins Released during Apoptotic and Necroptotic Cell Death. Cell Rep 2020; 30:1260-1270.e5. [DOI: 10.1016/j.celrep.2019.12.079] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 11/07/2019] [Accepted: 12/19/2019] [Indexed: 12/16/2022] Open
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9
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Panicker LM, Srikanth MP, Castro-Gomes T, Miller D, Andrews NW, Feldman RA. Gaucher disease iPSC-derived osteoblasts have developmental and lysosomal defects that impair bone matrix deposition. Hum Mol Genet 2019; 27:811-822. [PMID: 29301038 DOI: 10.1093/hmg/ddx442] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 12/27/2017] [Indexed: 01/18/2023] Open
Abstract
Gaucher disease (GD) is caused by bi-allelic mutations in GBA1, the gene that encodes acid β-glucocerebrosidase (GCase). Individuals affected by GD have hematologic, visceral and bone abnormalities, and in severe cases there is also neurodegeneration. To shed light on the mechanisms by which mutant GBA1 causes bone disease, we examined the ability of human induced pluripotent stem cells (iPSC) derived from patients with Types 1, 2 and 3 GD, to differentiate to osteoblasts and carry out bone deposition. Differentiation of GD iPSC to osteoblasts revealed that these cells had developmental defects and lysosomal abnormalities that interfered with bone matrix deposition. Compared with controls, GD iPSC-derived osteoblasts exhibited reduced expression of osteoblast differentiation markers, and bone matrix protein and mineral deposition were defective. Concomitantly, canonical Wnt/β catenin signaling in the mutant osteoblasts was downregulated, whereas pharmacological Wnt activation with the GSK3β inhibitor CHIR99021 rescued GD osteoblast differentiation and bone matrix deposition. Importantly, incubation with recombinant GCase (rGCase) rescued the differentiation and bone-forming ability of GD osteoblasts, demonstrating that the abnormal GD phenotype was caused by GCase deficiency. GD osteoblasts were also defective in their ability to carry out Ca2+-dependent exocytosis, a lysosomal function that is necessary for bone matrix deposition. We conclude that normal GCase enzymatic activity is required for the differentiation and bone-forming activity of osteoblasts. Furthermore, the rescue of bone matrix deposition by pharmacological activation of Wnt/β catenin in GD osteoblasts uncovers a new therapeutic target for the treatment of bone abnormalities in GD.
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Affiliation(s)
- Leelamma M Panicker
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Manasa P Srikanth
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Thiago Castro-Gomes
- Department of Cell Biology and Molecular Genetics, University of Maryland College Park, MD 20742, USA
| | - Diana Miller
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Norma W Andrews
- Department of Cell Biology and Molecular Genetics, University of Maryland College Park, MD 20742, USA
| | - Ricardo A Feldman
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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10
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Tharkeshwar AK, Gevaert K, Annaert W. Organellar Omics-A Reviving Strategy to Untangle the Biomolecular Complexity of the Cell. Proteomics 2017; 18:e1700113. [PMID: 29125683 DOI: 10.1002/pmic.201700113] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Revised: 10/23/2017] [Indexed: 12/18/2022]
Abstract
A eukaryotic cell encompasses many membrane-enclosed organelles, each of these holding several types of biomolecules that exhibit tremendous diversity in terms of their localization and expression. Despite the development of increasingly sensitive analytical tools, the enormous biomolecular complexity that exists within a cell cannot yet be fully resolved as low abundant molecules often remain unrecognized. Moreover, a drawback of whole cell analysis is that it does not provide spatial information and therefore it is not capable of assigning distinct biomolecules to specific compartments or analyzing changes in the composition of these compartments. Reduction of the biomolecular complexity of a sample helps to identify low abundant molecules, but such a reductionist approach requires methods that enable proper isolation and purification of individual cellular organelles. Decades of research have led to the development of a plethora of isolation methods for a broad range of subcellular organelles; yet, in particular, intrinsically dynamic compartments belonging to the endocytic machinery, including the plasma membrane, remain difficult to isolate in a sufficiently pure fraction. In this review, we discuss various methods that are commonly used to isolate subcellular organelles from cells and evaluate their advantages and disadvantages.
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Affiliation(s)
- Arun Kumar Tharkeshwar
- Laboratory for Membrane Trafficking, VIB-Center for Brain and Disease Research, Leuven, Belgium.,Laboratory for Membrane Trafficking, Department of Neurosciences, KU Leuven, Leuven, Belgium.,Department of Cell Biology, Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT, USA
| | - Kris Gevaert
- VIB-UGent Center for Medical Biotechnology, Ghent, Belgium.,Department of Biochemistry, Ghent University, Belgium
| | - Wim Annaert
- Laboratory for Membrane Trafficking, VIB-Center for Brain and Disease Research, Leuven, Belgium.,Laboratory for Membrane Trafficking, Department of Neurosciences, KU Leuven, Leuven, Belgium
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11
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Encarnação M, Espada L, Escrevente C, Mateus D, Ramalho J, Michelet X, Santarino I, Hsu VW, Brenner MB, Barral DC, Vieira OV. A Rab3a-dependent complex essential for lysosome positioning and plasma membrane repair. J Cell Biol 2017; 213:631-40. [PMID: 27325790 PMCID: PMC4915190 DOI: 10.1083/jcb.201511093] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 05/27/2016] [Indexed: 11/22/2022] Open
Abstract
Encarnação et al. show that Rab3a, together with its newly identified effector NMHC IIA, mediates the positioning of peripheral lysosomes in nonsecretory cells, thereby promoting lysosome exocytosis and plasma membrane repair. Lysosome exocytosis plays a major role in resealing plasma membrane (PM) disruptions. This process involves two sequential steps. First, lysosomes are recruited to the periphery of the cell and then fuse with the damaged PM. However, the trafficking molecular machinery involved in lysosome exocytosis and PM repair (PMR) is poorly understood. We performed a systematic screen of the human Rab family to identify Rabs required for lysosome exocytosis and PMR. Rab3a, which partially localizes to peripheral lysosomes, was one of the most robust hits. Silencing of Rab3a or its effector, synaptotagmin-like protein 4a (Slp4-a), leads to the collapse of lysosomes to the perinuclear region and inhibition of PMR. Importantly, we have also identified a new Rab3 effector, nonmuscle myosin heavy chain IIA, as part of the complex formed by Rab3a and Slp4-a that is responsible for lysosome positioning at the cell periphery and lysosome exocytosis.
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Affiliation(s)
- Marisa Encarnação
- Centro de Estudos de Doenças Crónicas, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, 1169-056 Lisboa, Portugal
| | - Lília Espada
- Centro de Estudos de Doenças Crónicas, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, 1169-056 Lisboa, Portugal
| | - Cristina Escrevente
- Centro de Estudos de Doenças Crónicas, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, 1169-056 Lisboa, Portugal
| | - Denisa Mateus
- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
| | - José Ramalho
- Centro de Estudos de Doenças Crónicas, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, 1169-056 Lisboa, Portugal
| | - Xavier Michelet
- Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115
| | - Inês Santarino
- Centro de Estudos de Doenças Crónicas, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, 1169-056 Lisboa, Portugal
| | - Victor W Hsu
- Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115
| | - Michael B Brenner
- Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115
| | - Duarte C Barral
- Centro de Estudos de Doenças Crónicas, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, 1169-056 Lisboa, Portugal
| | - Otília V Vieira
- Centro de Estudos de Doenças Crónicas, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, 1169-056 Lisboa, Portugal
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12
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Cong X, Hubmayr RD, Li C, Zhao X. Plasma membrane wounding and repair in pulmonary diseases. Am J Physiol Lung Cell Mol Physiol 2017; 312:L371-L391. [PMID: 28062486 PMCID: PMC5374305 DOI: 10.1152/ajplung.00486.2016] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 01/05/2017] [Accepted: 01/05/2017] [Indexed: 12/12/2022] Open
Abstract
Various pathophysiological conditions such as surfactant dysfunction, mechanical ventilation, inflammation, pathogen products, environmental exposures, and gastric acid aspiration stress lung cells, and the compromise of plasma membranes occurs as a result. The mechanisms necessary for cells to repair plasma membrane defects have been extensively investigated in the last two decades, and some of these key repair mechanisms are also shown to occur following lung cell injury. Because it was theorized that lung wounding and repair are involved in the pathogenesis of acute respiratory distress syndrome (ARDS) and idiopathic pulmonary fibrosis (IPF), in this review, we summarized the experimental evidence of lung cell injury in these two devastating syndromes and discuss relevant genetic, physical, and biological injury mechanisms, as well as mechanisms used by lung cells for cell survival and membrane repair. Finally, we discuss relevant signaling pathways that may be activated by chronic or repeated lung cell injury as an extension of our cell injury and repair focus in this review. We hope that a holistic view of injurious stimuli relevant for ARDS and IPF could lead to updated experimental models. In addition, parallel discussion of membrane repair mechanisms in lung cells and injury-activated signaling pathways would encourage research to bridge gaps in current knowledge. Indeed, deep understanding of lung cell wounding and repair, and discovery of relevant repair moieties for lung cells, should inspire the development of new therapies that are likely preventive and broadly effective for targeting injurious pulmonary diseases.
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Affiliation(s)
- Xiaofei Cong
- Department of Physiological Sciences, Eastern Virginia Medical School, Norfolk, Virginia
| | - Rolf D Hubmayr
- Emerius, Thoracic Diseases Research Unit, Mayo Clinic, Rochester, Minnesota; and
| | - Changgong Li
- Department of Pediatrics, University of Southern California, Los Angeles, California
| | - Xiaoli Zhao
- Department of Physiological Sciences, Eastern Virginia Medical School, Norfolk, Virginia;
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Boye TL, Nylandsted J. Annexins in plasma membrane repair. Biol Chem 2016; 397:961-9. [DOI: 10.1515/hsz-2016-0171] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 06/14/2016] [Indexed: 01/01/2023]
Abstract
Abstract
Disruption of the plasma membrane poses deadly threat to eukaryotic cells and survival requires a rapid membrane repair system. Recent evidence reveal various plasma membrane repair mechanisms, which are required for cells to cope with membrane lesions including membrane fusion and replacement strategies, remodeling of cortical actin cytoskeleton and vesicle wound patching. Members of the annexin protein family, which are Ca2+-triggered phospholipid-binding proteins emerge as important components of the plasma membrane repair system. Here, we discuss the mechanisms of plasma membrane repair involving annexins spanning from yeast to human cancer cells.
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14
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Upadhyay S, Xu X, Lowry D, Jackson JC, Roberson RW, Lin X. Subcellular Compartmentalization and Trafficking of the Biosynthetic Machinery for Fungal Melanin. Cell Rep 2016; 14:2511-8. [PMID: 26972005 DOI: 10.1016/j.celrep.2016.02.059] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Revised: 01/08/2016] [Accepted: 02/10/2016] [Indexed: 12/22/2022] Open
Abstract
Protection by melanin depends on its subcellular location. Although most filamentous fungi synthesize melanin via a polyketide synthase pathway, where and how melanin biosynthesis occurs and how it is deposited as extracellular granules remain elusive. Using a forward genetic screen in the pathogen Aspergillus fumigatus, we find that mutations in an endosomal sorting nexin abolish melanin cell-wall deposition. We find that all enzymes involved in the early steps of melanin biosynthesis are recruited to endosomes through a non-conventional secretory pathway. In contrast, late melanin enzymes accumulate in the cell wall. Such subcellular compartmentalization of the melanin biosynthetic machinery occurs in both A. fumigatus and A. nidulans. Thus, fungal melanin biosynthesis appears to be initiated in endosomes with exocytosis leading to melanin extracellular deposition, much like the synthesis and trafficking of mammalian melanin in endosomally derived melanosomes.
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Affiliation(s)
- Srijana Upadhyay
- Department of Biology, Texas A&M University, College Station, TX 77843, USA
| | - Xinping Xu
- Department of Biology, Texas A&M University, College Station, TX 77843, USA
| | - David Lowry
- School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA
| | - Jennifer C Jackson
- Department of Biology, Texas A&M University, College Station, TX 77843, USA
| | - Robert W Roberson
- School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA
| | - Xiaorong Lin
- Department of Biology, Texas A&M University, College Station, TX 77843, USA.
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15
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de Morais CGV, Castro Lima AK, Terra R, dos Santos RF, Da-Silva SAG, Dutra PML. The Dialogue of the Host-Parasite Relationship: Leishmania spp. and Trypanosoma cruzi Infection. BIOMED RESEARCH INTERNATIONAL 2015; 2015:324915. [PMID: 26090399 PMCID: PMC4450238 DOI: 10.1155/2015/324915] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 09/01/2014] [Accepted: 09/02/2014] [Indexed: 01/11/2023]
Abstract
The intracellular protozoa Leishmania spp. and Trypanosoma cruzi and the causative agents of Leishmaniasis and Chagas disease, respectively, belong to the Trypanosomatidae family. Together, these two neglected tropical diseases affect approximately 25 million people worldwide. Whether the host can control the infection or develops disease depends on the complex interaction between parasite and host. Parasite surface and secreted molecules are involved in triggering specific signaling pathways essential for parasite entry and intracellular survival. The recognition of the parasite antigens by host immune cells generates a specific immune response. Leishmania spp. and T. cruzi have a multifaceted repertoire of strategies to evade or subvert the immune system by interfering with a range of signal transduction pathways in host cells, which causes the inhibition of the protective response and contributes to their persistence in the host. The current therapeutic strategies in leishmaniasis and trypanosomiasis are very limited. Efficacy is variable, toxicity is high, and the emergence of resistance is increasingly common. In this review, we discuss the molecular basis of the host-parasite interaction of Leishmania and Trypanosoma cruzi infection and their mechanisms of subverting the immune response and how this knowledge can be used as a tool for the development of new drugs.
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Affiliation(s)
- Carlos Gustavo Vieira de Morais
- Laboratório de Bioquímica de Protozoários e Imunofisiologia do Exercício, Disciplina de Parasitologia, DMIP, FCM, Universidade do Estado do Rio de Janeiro, Avenida Professor Manuel de Abreu 444, Pavilhão Américo Piquet Carneiro, 5° andar, Vila Isabel, 20550-170 Rio de Janeiro, RJ, Brazil
- Programa de Pós Graduação em Microbiologia/FCM/UERJ, Avenida Professor Manuel de Abreu 444, Pavilhão Américo Piquet Carneiro, 3° andar, Vila Isabel, 20550-170 Rio de Janeiro, RJ, Brazil
| | - Ana Karina Castro Lima
- Laboratório de Bioquímica de Protozoários e Imunofisiologia do Exercício, Disciplina de Parasitologia, DMIP, FCM, Universidade do Estado do Rio de Janeiro, Avenida Professor Manuel de Abreu 444, Pavilhão Américo Piquet Carneiro, 5° andar, Vila Isabel, 20550-170 Rio de Janeiro, RJ, Brazil
| | - Rodrigo Terra
- Laboratório de Bioquímica de Protozoários e Imunofisiologia do Exercício, Disciplina de Parasitologia, DMIP, FCM, Universidade do Estado do Rio de Janeiro, Avenida Professor Manuel de Abreu 444, Pavilhão Américo Piquet Carneiro, 5° andar, Vila Isabel, 20550-170 Rio de Janeiro, RJ, Brazil
- Programa de Pós Graduação em Fisiopatologia Clínica e Experimental/FCM/UERJ, Avenida Professor Manuel de Abreu 444, Pavilhão Américo Piquet Carneiro, 5° andar, Vila Isabel, 20550-170 Rio de Janeiro, RJ, Brazil
| | - Rosiane Freire dos Santos
- Programa de Pós Graduação em Microbiologia/FCM/UERJ, Avenida Professor Manuel de Abreu 444, Pavilhão Américo Piquet Carneiro, 3° andar, Vila Isabel, 20550-170 Rio de Janeiro, RJ, Brazil
- Laboratório de Imunofarmacologia Parasitária, Disciplina de Parasitologia, DMIP, FCM, Universidade do Estado do Rio de Janeiro, Avenida Professor Manuel de Abreu 444, Pavilhão Américo Piquet Carneiro, 5° andar, Vila Isabel, 20550-170 Rio de Janeiro, RJ, Brazil
| | - Silvia Amaral Gonçalves Da-Silva
- Laboratório de Imunofarmacologia Parasitária, Disciplina de Parasitologia, DMIP, FCM, Universidade do Estado do Rio de Janeiro, Avenida Professor Manuel de Abreu 444, Pavilhão Américo Piquet Carneiro, 5° andar, Vila Isabel, 20550-170 Rio de Janeiro, RJ, Brazil
| | - Patrícia Maria Lourenço Dutra
- Laboratório de Bioquímica de Protozoários e Imunofisiologia do Exercício, Disciplina de Parasitologia, DMIP, FCM, Universidade do Estado do Rio de Janeiro, Avenida Professor Manuel de Abreu 444, Pavilhão Américo Piquet Carneiro, 5° andar, Vila Isabel, 20550-170 Rio de Janeiro, RJ, Brazil
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Abstract
Lysosomes were once considered the end point of endocytosis, simply used for macromolecule degradation. They are now recognized to be dynamic organelles, able to fuse with a variety of targets and to be re-formed after fusion events. They are also now known to be the site of nutrient sensing and signaling to the cell nucleus. In addition, lysosomes are secretory organelles, with specialized machinery for regulated secretion of proteins in some cell types. The biogenesis of lysosomes and lysosome-related organelles is discussed, taking into account their dynamic nature and multiple roles.
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17
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Oliveira IA, Freire-de-Lima L, Penha LL, Dias WB, Todeschini AR. Trypanosoma cruzi Trans-sialidase: structural features and biological implications. Subcell Biochem 2014; 74:181-201. [PMID: 24264246 DOI: 10.1007/978-94-007-7305-9_8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Trypanosoma cruzi trans-sialidase (TcTS) has intrigued researchers all over the world since it was shown that T. cruzi incorporates sialic acid through a mechanism independent of sialyltransferases. The enzyme has being involved in a vast myriad of functions in the biology of the parasite and in the pathology of Chagas' disease. At the structural level experiments trapping the intermediate with fluorosugars followed by peptide mapping, X-ray crystallography, molecular modeling and magnetic nuclear resonance have opened up a three-dimensional understanding of the way this enzyme works. Herein we review the multiple biological roles of TcTS and the structural studies that are slowly revealing the secrets underlining an efficient sugar transfer activity rather than simple hydrolysis by TcTS.
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Affiliation(s)
- Isadora A Oliveira
- Laboratório de Glicobiologia Estrutural e Funcional, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho, 373, Centro de Ciências da Saúde-Bloco D-3, 21941-902, Cidade Universitária, Rio de Janeiro, Brazil
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18
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Should I stay or should I go? Trafficking of sub-lytic MAC in the retinal pigment epithelium. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 801:267-74. [PMID: 24664707 DOI: 10.1007/978-1-4614-3209-8_34] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Assembly of sub-lytic C5b-9 membrane attack complexes (MAC) on the plasma membrane of retinal pigment epithelial cells contributes to the pathogenesis of age-related macular degeneration. C5b-9 pores induce calcium influx, which activates signaling pathways that compromise cell function. Mechanisms that limit sub-lytic MAC activity include: cell surface complement regulatory proteins CD46, CD55, and CD59 that inhibit specific steps of MAC formation; elimination of assembled MAC by exocytosis of membrane vesicles or by endocytosis and subsequent lysosomal degradation; and rapid resealing of pores by the exocytosis of lysosomes. Aging in the post-mitotic retinal pigment epithelium is characterized by the accumulation of cellular debris called lipofuscin, which has also been associated with retinal diseases such as age-related macular degeneration. Lipofuscin has been shown to activate complement components both in vitro and in vivo, suggesting that it could contribute complement-mediated dysfunction in the retinal pigment epithelium. Here, we discuss emerging evidence that vesicular trafficking in the retinal pigment epithelium is critical for efficient removal of MAC from the cell surface and for limiting inflammation in the outer retina.
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Castillo C, Villarroel A, Duaso J, Galanti N, Cabrera G, Maya JD, Kemmerling U. Phospholipase C gamma and ERK1/2 Mitogen Activated Kinase Pathways are differentially modulated by Trypanosoma cruzi during tissue invasion in human placenta. Exp Parasitol 2013; 133:12-7. [DOI: 10.1016/j.exppara.2012.10.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Revised: 10/08/2012] [Accepted: 10/19/2012] [Indexed: 02/07/2023]
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20
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Xu J, Toops KA, Diaz F, Carvajal-Gonzalez JM, Gravotta D, Mazzoni F, Schreiner R, Rodriguez-Boulan E, Lakkaraju A. Mechanism of polarized lysosome exocytosis in epithelial cells. J Cell Sci 2012; 125:5937-43. [PMID: 23038769 DOI: 10.1242/jcs.109421] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fusion of lysosomes with the plasma membrane is a calcium-dependent process that is crucial for membrane repair, limiting pathogen entry and clearing cellular debris. In non-polarized cells, lysosome exocytosis facilitates rapid resealing of torn membranes. Here, we investigate the mechanism of lysosome exocytosis in polarized epithelia, the main barrier between the organism and the external environment and the first line of defense against pathogens. We find that in polarized Madin-Darby canine kidney (MDCK) cells, calcium ionophores or pore-forming toxins cause lysosomes to fuse predominantly with the basolateral membrane. This polarized exocytosis is regulated by the actin cytoskeleton, membrane cholesterol and the clathrin adaptor AP-1. Depolymerization of actin, but not microtubules, causes apical lysosome fusion, supporting the hypothesis that cortical actin is a barrier to exocytosis. Overloading lysosomes with cholesterol inhibits exocytosis, suggesting that excess cholesterol paralyzes lysosomal traffic. The clathrin adaptor AP-1 is responsible for accurately targeting syntaxin 4 to the basolateral domain. In cells lacking either the ubiquitous AP-1A or the epithelial-specific AP-1B, syntaxin 4 is non-polar. This causes lysosomes to fuse with both the apical and basolateral membranes. Consistent with these findings, RNAi-mediated depletion of syntaxin 4 inhibits basolateral exocytosis in wild-type MDCK, and both apical and basolateral exocytosis in cells lacking AP-1A or AP-1B. Our results provide fundamental insight into the molecular machinery involved in membrane repair in polarized epithelia and suggest that AP-1 is a crucial regulator of this process.
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Affiliation(s)
- Jin Xu
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA
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21
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Romano PS, Cueto JA, Casassa AF, Vanrell MC, Gottlieb RA, Colombo MI. Molecular and cellular mechanisms involved in the Trypanosoma cruzi/host cell interplay. IUBMB Life 2012; 64:387-96. [PMID: 22454195 DOI: 10.1002/iub.1019] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Accepted: 02/10/2012] [Indexed: 01/12/2023]
Abstract
The protozoan parasite Trypanosoma cruzi has a complex biological cycle that involves vertebrate and invertebrate hosts. In mammals, the infective trypomastigote form of this parasite can invade several cell types by exploiting phagocytic-like or nonphagocytic mechanisms depending on the class of cell involved. Morphological studies showed that when trypomastigotes contact macrophages, they induce the formation of plasma membrane protrusions that differ from the canonical phagocytosis that occurs in the case of noninfective epimastigotes. In contrast, when trypomastigotes infect epithelial or muscle cells, the cell surface is minimally modified, suggesting the induction of a different class of process. Lysosomal-dependent or -independent T. cruzi invasion of host cells are two different models that describe the molecular and cellular events activated during parasite entry into nonphagocytic cells. In this context, we have previously shown that induction of autophagy in host cells before infection favors T. cruzi invasion. Furthermore, we demonstrate that autophagosomes and the autophagosomal protein LC3 are recruited to the T. cruzi entry sites and that the newly formed T. cruzi parasitophorous vacuole has characteristics of an autophagolysosome. This review summarizes the current knowledge of the molecular and cellular mechanisms of T. cruzi invasion in nonphagocytic cells. Based on our findings, we propose a new model in which T. cruzi takes advantage of the upregulation of autophagy during starvation to increase its successful colonization of host cells.
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Affiliation(s)
- Patricia Silvia Romano
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología (IHEM-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Cuyo-CONICET, Mendoza, Argentina.
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22
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Bastow ER, Last K, Golub S, Stow JL, Stanley AC, Fosang AJ. Evidence for lysosomal exocytosis and release of aggrecan-degrading hydrolases from hypertrophic chondrocytes, in vitro and in vivo. Biol Open 2012; 1:318-28. [PMID: 23213422 PMCID: PMC3509456 DOI: 10.1242/bio.2012547] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The abundant proteoglycan, aggrecan, is resorbed from growth plate cartilage during endochondral bone ossification, yet mice with genetically-ablated aggrecan-degrading activity have no defects in bone formation. To account for this apparent anomaly, we propose that lysosomal hydrolases degrade extracellular, hyaluronan-bound aggrecan aggregates in growth plate cartilage, and that lysosomal hydrolases are released from hypertrophic chondrocytes into growth plate cartilage via Ca2+-dependent lysosomal exocytosis. In this study we confirm that hypertrophic chondrocytes release hydrolases via lysosomal exocytosis in vitro and we show in vivo evidence for lysosomal exocytosis in hypertrophic chondrocytes during skeletal development. We show that lysosome-associated membrane protein 1 (LAMP1) is detected at the cell surface following in vitro treatment of epiphyseal chondrocytes with the calcium ionophore, ionomycin. Furthermore, we show that in addition to the lysosomal exocytosis markers, cathepsin D and β-hexosaminidase, ionomycin induces release of aggrecan- and hyaluronan-degrading activity from cultured epiphyseal chondrocytes. We identify VAMP-8 and VAMP7 as v-SNARE proteins with potential roles in lysosomal exocytosis in hypertrophic chondrocytes, based on their colocalisation with LAMP1 at the cell surface in secondary ossification centers in mouse tibiae. We propose that resorbing growth plate cartilage involves release of destructive hydrolases from hypertrophic chondrocytes, via lysosomal exocytosis.
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Affiliation(s)
- Edward R Bastow
- University of Melbourne Department of Paediatrics and Murdoch Childrens Research Institute, Royal Children's Hospital , Flemington Road, Parkville, VIC 3052 , Australia
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23
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Abstract
Phagocytosis is used by macrophages, dendritic cells and neutrophils to capture and destroy pathogens and particulate antigens. Although localized assembly of actin filaments is the driving force for particle internalization, exocytosis of intracellular compartments, and in particular endocytic compartments, has been shown recently to be required for the early steps of phagosome formation. Here we report on the different compartments undergoing exocytosis during phagocytosis, with a special focus on late endosomes. We then compare this process with secretion from lysosomes or lysosome-related organelles in specialized cells. Finally, we discuss how some of the molecular mechanisms responsible for lysosome-related organelle secretion could also be implicated in phagosome formation.
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Affiliation(s)
- Virginie Braun
- Membrane and Cytoskeleton Dynamics group, Institut Curie, CNRS UMR144, 75005 Paris, France
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24
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Caradonna KL, Burleigh BA. Mechanisms of host cell invasion by Trypanosoma cruzi. ADVANCES IN PARASITOLOGY 2011; 76:33-61. [PMID: 21884886 DOI: 10.1016/b978-0-12-385895-5.00002-5] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
One of the more accepted concepts in our understanding of the biology of early Trypanosoma cruzi-host cell interactions is that the mammalian-infective trypomastigote forms of the parasite must transit the host cell lysosomal compartment in order to establish a productive intracellular infection. The acidic environment of the lysosome provides the appropriate conditions for parasite-mediated disruption of the parasitophorous vacuole and release of T. cruzi into the host cell cytosol, where replication of intracellular amastigotes occurs. Recent findings indicate a level of redundancy in the lysosome-targeting process where T. cruzi trypomastigotes exploit different cellular pathways to access host cell lysosomes in non-professional phagocytic cells. In addition, the reversible nature of the host cell penetration process was recently demonstrated when conditions for fusion of the nascent parasite vacuole with the host endosomal-lysosomal system were not met. Thus, the concept of parasite retention as a critical component of the T. cruzi invasion process was introduced. Although it is clear that host cell recognition, attachment and signalling are required to initiate invasion, integration of this knowledge with our understanding of the different routes of parasite entry is largely lacking. In this chapter, we focus on current knowledge of the cellular pathways exploited by T. cruzi trypomastigotes to invade non-professional phagocytic cells and to gain access to the host cell lysosome compartment.
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Affiliation(s)
- Kacey L Caradonna
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston,Massachusetts, USA
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25
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Thimiri Govinda Raj DB, Ghesquière B, Tharkeshwar AK, Coen K, Derua R, Vanderschaeghe D, Rysman E, Bagadi M, Baatsen P, De Strooper B, Waelkens E, Borghs G, Callewaert N, Swinnen J, Gevaert K, Annaert W. A novel strategy for the comprehensive analysis of the biomolecular composition of isolated plasma membranes. Mol Syst Biol 2011; 7:541. [PMID: 22027552 PMCID: PMC3261717 DOI: 10.1038/msb.2011.74] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Accepted: 09/07/2011] [Indexed: 02/07/2023] Open
Abstract
We manufactured a novel type of lipid-coated superparamagnetic nanoparticles that allow for a rapid isolation of plasma membranes (PMs), enabling high-resolution proteomic, glycomic and lipidomic analyses of the cell surface. We used this technology to characterize the effects of presenilin knockout on the PM composition of mouse embryonic fibroblasts. We found that many proteins are selectively downregulated at the cell surface of presenilin knockout cells concomitant with lowered surface levels of cholesterol and certain sphingomyelin species, indicating defects in specific endosomal transport routes to and/or from the cell surface. Snapshots of N-glycoproteomics and cell surface glycan profiling further underscored the power and versatility of this novel methodology. Since PM proteins provide many pathologically relevant biomarkers representing two-thirds of the currently used drug targets, this novel technology has great potential for biomedical and pharmaceutical applications.
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Affiliation(s)
- Deepak B Thimiri Govinda Raj
- Department of Molecular and Developmental Genetics (VIB11), Laboratory for Membrane Trafficking and Center for Human Genetics (KULeuven), Gasthuisberg O&N4, Leuven, Belgium
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26
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Forestier CL, Machu C, Loussert C, Pescher P, Späth GF. Imaging host cell-Leishmania interaction dynamics implicates parasite motility, lysosome recruitment, and host cell wounding in the infection process. Cell Host Microbe 2011; 9:319-30. [PMID: 21501831 DOI: 10.1016/j.chom.2011.03.011] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 10/04/2010] [Accepted: 03/14/2011] [Indexed: 12/25/2022]
Abstract
Leishmania donovani causes human visceral leishmaniasis. The parasite infectious cycle comprises extracellular flagellated promastigotes that proliferate inside the insect vector, and intracellular nonmotile amastigotes that multiply within infected host cells. Using primary macrophages infected with virulent metacyclic promastigotes and high spatiotemporal resolution microscopy, we dissect the dynamics of the early infection process. We find that motile promastigotes enter macrophages in a polarized manner through their flagellar tip and are engulfed into host lysosomal compartments. Persistent intracellular flagellar activity leads to reorientation of the parasite flagellum toward the host cell periphery and results in oscillatory parasite movement. The latter is associated with local lysosomal exocytosis and host cell plasma membrane wounding. These findings implicate lysosome recruitment followed by lysosome exocytosis, consistent with parasite-driven host cell injury, as key cellular events in Leishmania host cell infection. This work highlights the role of promastigote polarity and motility during parasite entry.
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Teixeira ARL, Hecht MM, Guimaro MC, Sousa AO, Nitz N. Pathogenesis of chagas' disease: parasite persistence and autoimmunity. Clin Microbiol Rev 2011; 24:592-630. [PMID: 21734249 PMCID: PMC3131057 DOI: 10.1128/cmr.00063-10] [Citation(s) in RCA: 147] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Acute Trypanosoma cruzi infections can be asymptomatic, but chronically infected individuals can die of Chagas' disease. The transfer of the parasite mitochondrial kinetoplast DNA (kDNA) minicircle to the genome of chagasic patients can explain the pathogenesis of the disease; in cases of Chagas' disease with evident cardiomyopathy, the kDNA minicircles integrate mainly into retrotransposons at several chromosomes, but the minicircles are also detected in coding regions of genes that regulate cell growth, differentiation, and immune responses. An accurate evaluation of the role played by the genotype alterations in the autoimmune rejection of self-tissues in Chagas' disease is achieved with the cross-kingdom chicken model system, which is refractory to T. cruzi infections. The inoculation of T. cruzi into embryonated eggs prior to incubation generates parasite-free chicks, which retain the kDNA minicircle sequence mainly in the macrochromosome coding genes. Crossbreeding transfers the kDNA mutations to the chicken progeny. The kDNA-mutated chickens develop severe cardiomyopathy in adult life and die of heart failure. The phenotyping of the lesions revealed that cytotoxic CD45, CD8(+) γδ, and CD8α(+) T lymphocytes carry out the rejection of the chicken heart. These results suggest that the inflammatory cardiomyopathy of Chagas' disease is a genetically driven autoimmune disease.
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Affiliation(s)
- Antonio R L Teixeira
- Chagas Disease Multidisciplinary Research Laboratory, University of Brasilia, Federal District, Brazil.
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28
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Laulagnier K, Schieber NL, Maritzen T, Haucke V, Parton RG, Gruenberg J. Role of AP1 and Gadkin in the traffic of secretory endo-lysosomes. Mol Biol Cell 2011; 22:2068-82. [PMID: 21525240 PMCID: PMC3113771 DOI: 10.1091/mbc.e11-03-0193] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2011] [Revised: 04/12/2011] [Accepted: 04/19/2011] [Indexed: 11/11/2022] Open
Abstract
Whereas lysosome-related organelles (LRO) of specialized cells display both exocytic and endocytic features, lysosomes in nonspecialized cells can also acquire the property to fuse with the plasma membrane upon an acute rise in cytosolic calcium. Here, we characterize this unconventional secretory pathway in fibroblast-like cells, by monitoring the appearance of Lamp1 on the plasma membrane and the release of lysosomal enzymes into the medium. After sequential ablation of endocytic compartments in living cells, we find that donor membranes primarily derive from a late compartment, but that an early compartment is also involved. Strikingly, this endo-secretory process is not affected by treatments that inhibit endosome dynamics (microtubule depolymerization, cholesterol accumulation, overexpression of Rab7 or its effector Rab-interacting lysosomal protein [RILP], overexpression of Rab5 mutants), but depends on Rab27a, a GTPase involved in LRO secretion, and is controlled by F-actin. Moreover, we find that this unconventional endo-secretory pathway requires the adaptor protein complexes AP1, Gadkin (which recruits AP1 by binding to the γ1 subunit), and AP2, but not AP3. We conclude that a specific fraction of the AP2-derived endocytic pathway is dedicated to secretory purposes under the control of AP1 and Gadkin.
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Affiliation(s)
- Karine Laulagnier
- Department of Biochemistry, University of Geneva, 1211-Geneva-4, Switzerland
| | - Nicole L. Schieber
- Institute for Molecular Bioscience and Center for Microscopy and Microanalysis, The University of Queensland, Brisbane 4072, Australia
| | - Tanja Maritzen
- Laboratory of Membrane Biochemistry, Freie Universitaet Berlin, 14195 Berlin, Germany
| | - Volker Haucke
- Laboratory of Membrane Biochemistry, Freie Universitaet Berlin, 14195 Berlin, Germany
| | - Robert G. Parton
- Institute for Molecular Bioscience and Center for Microscopy and Microanalysis, The University of Queensland, Brisbane 4072, Australia
| | - Jean Gruenberg
- Department of Biochemistry, University of Geneva, 1211-Geneva-4, Switzerland
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29
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Bhattacharyya T, Brooks J, Yeo M, Carrasco HJ, Lewis MD, Llewellyn MS, Miles MA. Analysis of molecular diversity of the Trypanosoma cruzi trypomastigote small surface antigen reveals novel epitopes, evidence of positive selection and potential implications for lineage-specific serology. Int J Parasitol 2010; 40:921-8. [DOI: 10.1016/j.ijpara.2010.01.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2009] [Revised: 01/08/2010] [Accepted: 01/10/2010] [Indexed: 10/19/2022]
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Inheritance of DNA transferred from American trypanosomes to human hosts. PLoS One 2010; 5:e9181. [PMID: 20169193 PMCID: PMC2820539 DOI: 10.1371/journal.pone.0009181] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Accepted: 01/04/2010] [Indexed: 01/09/2023] Open
Abstract
Interspecies DNA transfer is a major biological process leading to the accumulation of mutations inherited by sexual reproduction among eukaryotes. Lateral DNA transfer events and their inheritance has been challenging to document. In this study we modified a thermal asymmetric interlaced PCR by using additional targeted primers, along with Southern blots, fluorescence techniques, and bioinformatics, to identify lateral DNA transfer events from parasite to host. Instances of naturally occurring human infections by Trypanosoma cruzi are documented, where mitochondrial minicircles integrated mainly into retrotransposable LINE-1 of various chromosomes. The founders of five families show minicircle integrations that were transferred vertically to their progeny. Microhomology end-joining of 6 to 22 AC-rich nucleotide repeats in the minicircles and host DNA mediates foreign DNA integration. Heterogeneous minicircle sequences were distributed randomly among families, with diversity increasing due to subsequent rearrangement of inserted fragments. Mosaic recombination and hitchhiking on retrotransposition events to different loci were more prevalent in germ line as compared to somatic cells. Potential new genes, pseudogenes, and knockouts were identified. A pathway of minicircle integration and maintenance in the host genome is suggested. Thus, infection by T. cruzi has the unexpected consequence of increasing human genetic diversity, and Chagas disease may be a fortuitous share of negative selection. This demonstration of contemporary transfer of eukaryotic DNA to the human genome and its subsequent inheritance by descendants introduces a significant change in the scientific concept of evolutionary biology and medicine.
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Teixeira ARL, Gomes C, Lozzi SP, Hecht MM, Rosa ADC, Monteiro PS, Bussacos AC, Nitz N, McManus C. Environment, interactions between Trypanosoma cruzi and its host, and health. CAD SAUDE PUBLICA 2009; 25 Suppl 1:S32-44. [PMID: 19287864 DOI: 10.1590/s0102-311x2009001300004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2007] [Accepted: 04/09/2008] [Indexed: 12/14/2022] Open
Abstract
An epidemiological chain involving Trypanosoma cruzi is discussed at the environmental level, and in terms of fine molecular interactions in invertebrate and vertebrate hosts dwelling in different ecosystems. This protozoan has a complex, genetically controlled plasticity, which confers adaptation to approximately 40 blood-sucking triatomine species and to over 1,000 mammalian species, fulfilling diverse metabolic requirements in its complex life-cycle. The Tr. cruzi infections are deeply embedded in countless ecotypes, where they are difficult to defeat using the control methods that are currently available. Many more field and laboratory studies are required to obtain data and information that may be used for the control and prevention of Tr. cruzi infections and their various disease manifestations. Emphasis should be placed on those sensitive interactions at cellular and environmental levels that could become selected targets for disease prevention. In the short term, new technologies for social mobilization should be used by people and organizations working for justice and equality through health information and promotion. A mass media directed program could deliver education, information and communication to protect the inhabitants at risk of contracting Tr. cruzi infections.
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Alves MJM, Mortara RA. A century of research: what have we learned about the interaction of Trypanosoma cruzi with host cells? Mem Inst Oswaldo Cruz 2009; 104 Suppl 1:76-88. [DOI: 10.1590/s0074-02762009000900013] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2009] [Accepted: 05/29/2009] [Indexed: 12/31/2022] Open
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Gaspar EB, Mortara RA, Andrade LO, da Silva CV. Lysosomal exocytosis: an important event during invasion of lamp deficient cells by extracellular amastigotes of Trypanosoma cruzi. Biochem Biophys Res Commun 2009; 384:265-9. [PMID: 19406103 DOI: 10.1016/j.bbrc.2009.04.114] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2009] [Accepted: 04/22/2009] [Indexed: 01/02/2023]
Abstract
Trypanosoma cruzi is an obligate intracellular organism in vertebrate hosts. Lysosomes are involved in parasite invasion. LAMP-1 and LAMP-2 are the most abundant glycoproteins of the lysosomal membrane. This study is the first report on the invasion of T. cruzi extracellular amastigotes (EA) in single LAMP-1 or LAMP-2 knockouts, respectively, or in two independent LAMP-1/2 double-knockout cell lines. When compared to their respective wild type clones, the EA show higher infectivity in LAMP-2 knockouts, but no difference was seen in LAMP-1 knockout cells. Similarly, EA invasion rate was higher for one of the double knockout clones but not for the other. Higher lysosomal exocytosis correlated with a higher invasion rate and early lysosomal marker acquisition. These findings suggest that lysosomal exocytosis is important to EA cell invasion. Also, phagolysosome maturation in knockout cell lines differed from previous results revealing that EA enter cells by a mechanism other than receptor-mediated phagocytosis.
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Affiliation(s)
- Emanuelle Baldo Gaspar
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, Rua Botucatu 862, 6 Degrees Andar, São Paulo 04023-062 SP, Brazil
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de Souza W, Sant'Anna C, Cunha-e-Silva NL. Electron microscopy and cytochemistry analysis of the endocytic pathway of pathogenic protozoa. ACTA ACUST UNITED AC 2009; 44:67-124. [PMID: 19410686 DOI: 10.1016/j.proghi.2009.01.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Endocytosis is essential for eukaryotic cell survival and has been well characterized in mammal and yeast cells. Among protozoa it is also important for evading from host immune defenses and to support intense proliferation characteristic of some life cycle stages. Here we focused on the contribution of morphological and cytochemical studies to the understanding of endocytosis in Trichomonas, Giardia, Entamoeba, Plasmodium, and trypanosomatids, mainly Trypanosoma cruzi, and also Trypanosoma brucei and Leishmania.
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Affiliation(s)
- Wanderley de Souza
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Cidade Universitária, Ilha do Fundão, Rio de Janeiro 21941-902, Brazil.
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35
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Zhu GD, Salazar G, Zlatic SA, Fiza B, Doucette MM, Heilman CJ, Levey AI, Faundez V, L'Hernault SW. SPE-39 family proteins interact with the HOPS complex and function in lysosomal delivery. Mol Biol Cell 2009; 20:1223-40. [PMID: 19109425 PMCID: PMC2642739 DOI: 10.1091/mbc.e08-07-0728] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2008] [Revised: 12/02/2008] [Accepted: 12/05/2008] [Indexed: 01/19/2023] Open
Abstract
Yeast and animal homotypic fusion and vacuole protein sorting (HOPS) complexes contain conserved subunits, but HOPS-mediated traffic in animals might require additional proteins. Here, we demonstrate that SPE-39 homologues, which are found only in animals, are present in RAB5-, RAB7-, and RAB11-positive endosomes where they play a conserved role in lysosomal delivery and probably function via their interaction with the core HOPS complex. Although Caenorhabditis elegans spe-39 mutants were initially identified as having abnormal vesicular biogenesis during spermatogenesis, we show that these mutants also have disrupted processing of endocytosed proteins in oocytes and coelomocytes. C. elegans SPE-39 interacts in vitro with both VPS33A and VPS33B, whereas RNA interference of VPS33B causes spe-39-like spermatogenesis defects. The human SPE-39 orthologue C14orf133 also interacts with VPS33 homologues and both coimmunoprecipitates and cosediments with other HOPS subunits. SPE-39 knockdown in cultured human cells altered the morphology of syntaxin 7-, syntaxin 8-, and syntaxin 13-positive endosomes. These effects occurred concomitantly with delayed mannose 6-phosphate receptor-mediated cathepsin D delivery and degradation of internalized epidermal growth factor receptors. Our findings establish that SPE-39 proteins are a previously unrecognized regulator of lysosomal delivery and that C. elegans spermatogenesis is an experimental system useful for identifying conserved regulators of metazoan lysosomal biogenesis.
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Affiliation(s)
| | | | - Stephanie A. Zlatic
- Graduate Program in Biochemistry, Cell, and Developmental Biology
- Cell Biology, and
| | | | | | - Craig J. Heilman
- Department of Neurology
- Center for Neurodegenerative Disease, Emory University, Atlanta, GA 30322
| | - Allan I. Levey
- Department of Neurology
- Center for Neurodegenerative Disease, Emory University, Atlanta, GA 30322
| | - Victor Faundez
- Graduate Program in Biochemistry, Cell, and Developmental Biology
- Cell Biology, and
- Center for Neurodegenerative Disease, Emory University, Atlanta, GA 30322
| | - Steven W. L'Hernault
- Graduate Program in Biochemistry, Cell, and Developmental Biology
- Departments of *Biology and
- Center for Neurodegenerative Disease, Emory University, Atlanta, GA 30322
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36
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Fulton L, Batoux M, Vaddepalli P, Yadav RK, Busch W, Andersen SU, Jeong S, Lohmann JU, Schneitz K. DETORQUEO, QUIRKY, and ZERZAUST represent novel components involved in organ development mediated by the receptor-like kinase STRUBBELIG in Arabidopsis thaliana. PLoS Genet 2009; 5:e1000355. [PMID: 19180193 PMCID: PMC2628281 DOI: 10.1371/journal.pgen.1000355] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2008] [Accepted: 12/23/2008] [Indexed: 12/26/2022] Open
Abstract
Intercellular signaling plays an important role in controlling cellular behavior in apical meristems and developing organs in plants. One prominent example in Arabidopsis is the regulation of floral organ shape, ovule integument morphogenesis, the cell division plane, and root hair patterning by the leucine-rich repeat receptor-like kinase STRUBBELIG (SUB). Interestingly, kinase activity of SUB is not essential for its in vivo function, indicating that SUB may be an atypical or inactive receptor-like kinase. Since little is known about signaling by atypical receptor-like kinases, we used forward genetics to identify genes that potentially function in SUB-dependent processes and found recessive mutations in three genes that result in a sub-like phenotype. Plants with a defect in DETORQEO (DOQ), QUIRKY (QKY), and ZERZAUST (ZET) show corresponding defects in outer integument development, floral organ shape, and stem twisting. The mutants also show sub-like cellular defects in the floral meristem and in root hair patterning. Thus, SUB, DOQ, QKY, and ZET define the STRUBBELIG-LIKE MUTANT (SLM) class of genes. Molecular cloning of QKY identified a putative transmembrane protein carrying four C(2) domains, suggesting that QKY may function in membrane trafficking in a Ca(2+)-dependent fashion. Morphological analysis of single and all pair-wise double-mutant combinations indicated that SLM genes have overlapping, but also distinct, functions in plant organogenesis. This notion was supported by a systematic comparison of whole-genome transcript profiles during floral development, which molecularly defined common and distinct sets of affected processes in slm mutants. Further analysis indicated that many SLM-responsive genes have functions in cell wall biology, hormone signaling, and various stress responses. Taken together, our data suggest that DOQ, QKY, and ZET contribute to SUB-dependent organogenesis and shed light on the mechanisms, which are dependent on signaling through the atypical receptor-like kinase SUB.
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Affiliation(s)
- Lynette Fulton
- Entwicklungsbiologie der Pflanzen, Wissenschaftszentrum Weihenstephan, Technische Universität München, Freising, Germany
| | - Martine Batoux
- Entwicklungsbiologie der Pflanzen, Wissenschaftszentrum Weihenstephan, Technische Universität München, Freising, Germany
| | - Prasad Vaddepalli
- Entwicklungsbiologie der Pflanzen, Wissenschaftszentrum Weihenstephan, Technische Universität München, Freising, Germany
| | - Ram Kishor Yadav
- Entwicklungsbiologie der Pflanzen, Wissenschaftszentrum Weihenstephan, Technische Universität München, Freising, Germany
| | - Wolfgang Busch
- Max Planck Institute for Developmental Biology, Department of Molecular Biology, AG Lohmann, Tübingen, Germany
| | - Stig U. Andersen
- Max Planck Institute for Developmental Biology, Department of Molecular Biology, AG Lohmann, Tübingen, Germany
| | - Sangho Jeong
- Section of Cell and Developmental Biology, University of California San Diego, La Jolla, California, United States of America
| | - Jan U. Lohmann
- Max Planck Institute for Developmental Biology, Department of Molecular Biology, AG Lohmann, Tübingen, Germany
- Center for Organismal Studies, University of Heidelberg, Heidelberg, Germany
| | - Kay Schneitz
- Entwicklungsbiologie der Pflanzen, Wissenschaftszentrum Weihenstephan, Technische Universität München, Freising, Germany
- * E-mail:
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37
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Abstract
The cell-invasive, trypomastigote form of Trypanosoma cruzi exhibits a unique relationship with lysosomes in target host cells. In contrast to many intracellular pathogens that are adept at avoiding contact with lysosomes, T. cruzi requires transient residence within this acidic organelle for productive infection. The low pH environment of lysosomes facilitates parasite egress from the vacuole and delivery into the host cytosol, a critical step in the T. cruzi developmental program. Recent studies also suggest that early lysosome fusion with invading or recently internalized parasites is critical for cellular retention of parasites. To ensure targeting to host cell lysosomes, T. cruzi trypomastigotes exploit two distinct modes of invasion that rapidly converge in the cell. In this chapter, we summarize the recent progress and changing views regarding the role of host cell lysosomes in the T. cruzi infection process where our discussion is limited to invasion of nonprofessional phagocytic cells.
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Affiliation(s)
- G Adam Mott
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts 02115, USA
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38
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Eto DS, Gordon HB, Dhakal BK, Jones TA, Mulvey MA. Clathrin, AP-2, and the NPXY-binding subset of alternate endocytic adaptors facilitate FimH-mediated bacterial invasion of host cells. Cell Microbiol 2008; 10:2553-67. [PMID: 18754852 DOI: 10.1111/j.1462-5822.2008.01229.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The FimH adhesin, localized at the distal tips of type 1 pili, binds mannose-containing glycoprotein receptors like alpha3beta1 integrins and stimulates bacterial entry into target host cells. Strains of uropathogenic Escherichia coli (UPEC), the major cause of urinary tract infections, utilize FimH to invade bladder epithelial cells. Here we set out to define the mechanism by which UPEC enters host cells by investigating four of the major entry routes known to be exploited by invasive pathogens: caveolae, clathrin, macropinocytosis and secretory lysosomes. Using pharmacological inhibitors in combination with RNA interference against specific endocytic pathway components, mutant host cell lines and a mouse infection model system, we found that type 1 pili-dependent bacterial invasion of host cells occurs via a cholesterol- and dynamin-dependent phagocytosis-like mechanism. This process did not require caveolae or secretory lysosomes, but was modulated by calcium levels, clathrin, and cooperative input from the primary clathrin adaptor AP-2 and a subset of alternate adaptors comprised of Numb, ARH and Dab2. These alternate clathrin adaptors recognize NPXY motifs, as found within the cytosolic tail of beta1 integrin, suggesting a functional link between the engagement of integrin receptors by FimH and the clathrin-dependent uptake of type 1-piliated bacteria.
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Affiliation(s)
- Danelle S Eto
- Division of Cell Biology and Immunology, Pathology Department, University of Utah, Salt Lake City, UT 84112-0565, USA
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Araújo-Jorge TC, Waghabi MC, Soeiro MDNC, Keramidas M, Bailly S, Feige JJ. Pivotal role for TGF-beta in infectious heart disease: The case of Trypanosoma cruzi infection and consequent Chagasic myocardiopathy. Cytokine Growth Factor Rev 2008; 19:405-13. [PMID: 18938102 DOI: 10.1016/j.cytogfr.2008.08.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
This paper summarizes recent data from the literature suggesting that transforming growth factor-beta (TGF-beta) participates at least in four different processes influencing development of myocardiopathy in Chagas disease, a major parasitic illness caused by Trypanosoma cruzi infection: (a) invasion of cardiac fibroblasts and myocytes; (b) intracellular parasite cycle; (c) regulation of inflammation and immune response; (d) fibrosis and heart remodeling during acute and chronic disease. All these effects point to an important role of TGF-beta in Chagas disease myocardiopathy and suggest that monitoring the circulating levels of this cytokine could be of help in clinical prognosis and management of patients. Moreover, TGF-beta-interfering therapies appear as interesting adjuvant interventions during acute and chronic phases of T. cruzi infection.
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Affiliation(s)
- Tania C Araújo-Jorge
- Laboratório de Biologia Celular, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
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40
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The yeast lysosome-like vacuole: endpoint and crossroads. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2008; 1793:650-63. [PMID: 18786576 DOI: 10.1016/j.bbamcr.2008.08.003] [Citation(s) in RCA: 292] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Revised: 08/01/2008] [Accepted: 08/06/2008] [Indexed: 12/21/2022]
Abstract
Fungal vacuoles are acidic organelles with degradative and storage capabilities that have many similarities to mammalian lysosomes and plant vacuoles. In the past several years, well-developed genetic, genomic, biochemical and cell biological tools in S. cerevisiae have provided fresh insights into vacuolar protein sorting, organelle acidification, ion homeostasis, autophagy, and stress-related functions of the vacuole, and these insights have often found parallels in mammalian lysosomes. This review provides a broad overview of the defining features and functions of S. cerevisiae vacuoles and compares these features to mammalian lysosomes. Recent research challenges the traditional view of vacuoles and lysosomes as simply the terminal compartment of biosynthetic and endocytic pathways (i.e. the "garbage dump" of the cell), and suggests instead that these compartments are unexpectedly dynamic and highly regulated.
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41
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Nabavi N, Urukova Y, Cardelli M, Aubin JE, Harrison RE. Lysosome dispersion in osteoblasts accommodates enhanced collagen production during differentiation. J Biol Chem 2008; 283:19678-90. [PMID: 18463099 DOI: 10.1074/jbc.m802517200] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Lysosomes are essential organelles for intracellular degradation and are generally sequestered near the cell center to receive vesicles with contents targeted for destruction. During ascorbic acid (AA)-induced differentiation of osteogenic cells ( Beck, G. R., Jr., Zerler, B., and Moran, E. (2001) Cell Growth Differ. 12, 61-83 ), we saw a marked increase in total lysosome organelles in osteoblastic cells, in addition to an enhanced endocytic rate. Interestingly, lysosomes were dispersed toward the cell periphery in differentiating osteoblasts. We determined that lysosome dispersion in differentiated osteoblasts required intact microtubules for long range transport and was dependent on kinesin motors but did not involve cytosolic acidification. Impairment of lysosome dispersion markedly reduced AA-induced osteoblast differentiation. Lysosomes were not secreted in differentiated osteoblasts, implicating them instead in intracellular degradation. We assayed the degradative capacity and saw a significant increase in DQ-ovalbumin fluorescence in differentiated osteogenic cells compared with undifferentiated control cells. Osteogenic cells are specialized for type I collagen production, and we noted enhanced secreted and intracellular collagen in AA-differentiated osteoblasts versus control cells. Importantly, osteoblasts displayed procollagen-containing vesicles that were distributed throughout the cytoplasm, a portion of which colocalized with lysosomes. Treatment of cells with 2,2'-dipyridyl to inhibit procollagen trimerization enhanced colocalization of lysosomes with procollagen-containing organelles, implicating dispersed lysosomes in collagen processing in osteogenic cells.
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Affiliation(s)
- Noushin Nabavi
- Department of Cell and Systems Biology, Faculty of Medicine, University of Toronto Scarborough, Toronto, Ontario M1C 1A4 Canada
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42
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Maganto-Garcia E, Punzon C, Terhorst C, Fresno M. Rab5 activation by Toll-like receptor 2 is required for Trypanosoma cruzi internalization and replication in macrophages. Traffic 2008; 9:1299-315. [PMID: 18445119 DOI: 10.1111/j.1600-0854.2008.00760.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Trypanosoma cruzi can infect and replicate in macrophages. During invasion, T. cruzi interacts with different macrophage receptors to induce its own phagocytosis. However, the nature of those receptors and the molecular mechanisms involved are poorly understood. In this study, we demonstrate that T. cruzi metacyclic trypomastigotes but not epimastigotes were able to induce Rab5 activation and binding to the early endosomes in peritoneal macrophages. In this process, active Rab5 colocalized with parasites in the phagosome and with the Rab5A effector molecule early endosomal antigen 1. Phagosome formation and T. cruzi internalization were inhibited in Raw 264.7 macrophages expressing a dominant-negative form of Rab5 [(S34N)Rab5]. Using T. cruzi membrane extracts, we verified that the Rab5 activation depends on the interaction between parasite surface molecules and macrophages surface molecule. In addition, during infection of macrophages, phosphatidylinositol 3-kinase (PI3K) pathway was activated. Assays carried out using a selective PI3K inhibitor (LY294002) showed that the PI3K activation is essential for Rab5 activation by T. cruzi infection and for the entrance and intracellular replication of T. cruzi in macrophages. Moreover, using macrophages from knockout mice, we found that activation of Rab5, fusion of early endosomes and phagocytosis induced by T. cruzi infection involved Toll-like receptor (TLR)2 but were independent of TLR4 receptors.
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Affiliation(s)
- Elena Maganto-Garcia
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
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43
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Huynh KK, Kay JG, Stow JL, Grinstein S. Fusion, fission, and secretion during phagocytosis. Physiology (Bethesda) 2008; 22:366-72. [PMID: 18073409 DOI: 10.1152/physiol.00028.2007] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Phagocytosis is essential for the elimination of pathogens and for clearance of apoptotic bodies. The ingestion process entails extensive remodeling of the cellular membranes, particularly when large and/or multiple particles are engulfed. The membrane fusion and fission events that accompany phagocytosis are described. The coordinated sequence of membrane trafficking events required for phagocytosis involves multiple organelles and also serves other cellular functions, such as cytokine secretion.
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Affiliation(s)
- Kassidy K Huynh
- Division of Cell Biology, The Hospital for Sick Children, Toronto, Canada
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44
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Coggins MR, Grabner CP, Almers W, Zenisek D. Stimulated exocytosis of endosomes in goldfish retinal bipolar neurons. J Physiol 2007; 584:853-65. [PMID: 17823206 PMCID: PMC2276998 DOI: 10.1113/jphysiol.2007.140848] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
After exocytosis, synaptic vesicle components are selectively retrieved by clathrin-mediated endocytosis and then re-used in future rounds of transmitter release. Under some conditions, synaptic terminals in addition perform bulk endocytosis of large membranous sacs. Bulk endocytosis is less selective than clathrin-mediated endocytosis and probably internalizes components normally targeted to the plasma membrane. Nonetheless, this process plays a major role in some tonic ribbon-type synapses, which release neurotransmitter for prolonged periods of time. We show here, that large endosomes formed after strong and prolonged stimulation undergo stimulated exocytosis in retinal bipolar neurons. The result suggests how cells might return erroneously internalized components to the plasma membrane, and also demonstrates that synaptic vesicles are not the only neuronal organelle that stains with styryl dyes and undergoes stimulated exocytosis.
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Affiliation(s)
- Michael R Coggins
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA
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45
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Abstract
Endothelial cells are major participants in angiogenic processes accompanying wound repair. The functions of ABH histo-blood group antigens (HBGAs) and lysosome-associated membrane proteins LAMP-1 and LAMP-2 in endothelial cells of granulation tissue are currently unkown. Here we hypothesize that HBGAs and LAMPs enrich the phenotypic characteristics of endothelial cells and might be implicated in the plasticity of granulation tissue. Immunohistochemistry revealed permanent expression of HBGAs in the cytoplasm of endothelial cells of all sprouting capillaries regardless of the organ examined. A modulation in both the localization and the intensity of the signal for LAMPs was observed. Interestingly, LAMP-1 showed a more intensive staining compared to LAMP-2. LAMP-1 was found in the cytoplasm, as well as on plasma membranes of endothelial cells. We present the first comparative immunohistochemical study of the expression of HBGA and LAMPs in endothelial cells of granulation tissue. Novel evidence for modulating LAMP reactivity is reported. Our results suggest that both glycoconjugates might contribute to the process of neoangiogenesis and tissue remodeling in wound healing.
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46
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Teixeira ARL, Nascimento RJ, Sturm NR. Evolution and pathology in chagas disease--a review. Mem Inst Oswaldo Cruz 2007; 101:463-91. [PMID: 17072450 DOI: 10.1590/s0074-02762006000500001] [Citation(s) in RCA: 154] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2006] [Accepted: 06/07/2006] [Indexed: 02/04/2023] Open
Abstract
Trypanosoma cruzi acute infections often go unperceived, but one third of chronically infected individuals die of Chagas disease, showing diverse manifestations affecting the heart, intestines, and nervous systems. A common denominator of pathology in Chagas disease is the minimal rejection unit, whereby parasite-free target host cells are destroyed by immune system mononuclear effectors cells infiltrates. Another key feature stemming from T. cruzi infection is the integration of kDNA minicircles into the vertebrate host genome; horizontal transfer of the parasite DNA can undergo vertical transmission to the progeny of mammals and birds. kDNA integration-induced mutations can enter multiple loci in diverse chromosomes, generating new genes, pseudo genes and knock-outs, and resulting in genomic shuffling and remodeling over time. As a result of the juxtaposition of kDNA insertions with host open reading frames, novel chimeric products may be generated. Germ line transmission of kDNA-mutations determined the appearance of lesions in birds that are indistinguishable from those seen in Chagas disease patients. The production of tissue lesions showing typical minimal rejection units in birds' refractory to T. cruzi infection is consistent with the hypothesis that autoimmunity, likely triggered by integration-induced phenotypic alterations, plays a major role in the pathogenesis of Chagas disease.
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Affiliation(s)
- Antonio R L Teixeira
- Laboratório de Pesquisa Multidisciplinar em Doença de Chagas, Faculdade de Medicina, Universidade de Brasilia, Caixa Postal 04536, 70919-970 Brasilia,-DF, Brasil.
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47
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Bement WM, Yu HYE, Burkel BM, Vaughan EM, Clark AG. Rehabilitation and the single cell. Curr Opin Cell Biol 2007; 19:95-100. [PMID: 17174083 PMCID: PMC4364133 DOI: 10.1016/j.ceb.2006.12.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2006] [Accepted: 12/05/2006] [Indexed: 11/15/2022]
Abstract
Cellular damage triggers rapid resealing of the plasma membrane and repair of the cortical cytoskeleton. Plasma membrane resealing results from calcium-dependent fusion of membranous organelles and the plasma membrane at the site of the damage. Cortical cytoskeletal repair results from local assembly of actin filaments (F-actin), myosin-2 and microtubules into an array that closes around the original wound site. Control of the cytoskeletal response is exerted by local activation of the small GTPases, Rho and Cdc42. Recent work has given insight into both the membrane fusion and cytoskeletal responses to plasma membrane damage and we propose that Rho GTPase activation results at least in part from the events that drive membrane repair.
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Affiliation(s)
- William M Bement
- Department of Zoology, University of Wisconsin-Madison, 1117 West Johnson Street, Madison, WI 53706, USA.
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48
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Coutinho-Silva R, Monteiro da Cruz C, Persechini PM, Ojcius DM. The role of P2 receptors in controlling infections by intracellular pathogens. Purinergic Signal 2007; 3:83-90. [PMID: 18404421 PMCID: PMC2096763 DOI: 10.1007/s11302-006-9039-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2005] [Accepted: 01/13/2006] [Indexed: 01/10/2023] Open
Abstract
A growing number of studies have demonstrated the importance of ATP(e)-signalling via P2 receptors as an important component of the inflammatory response to infection. More recent studies have shown that ATP(e) can also have a direct effect on infection by intracellular pathogens, by modulating membrane trafficking in cells that contain vacuoles that harbour intracellular pathogens, such as mycobacteria and chlamydiae. A conserved mechanism appears to be involved in controlling infection by both of these pathogens, as a role for phospholipase D in inducing fusion between lysosomes and the vacuoles has been demonstrated. Other P2-dependent mechanisms are most likely operative in the cases of pathogens, such as Leishmania, which survive in an acidic phagolysosomal-like compartment. ATP(e) may function as a "danger signal" that alerts the immune system to the presence of intracellular pathogens that damage the host cell, while different intracellular pathogens have evolved enzymes or other mechanisms to inhibit ATP(e)-mediated signalling, which should, thus, be viewed as virulence factors for these pathogens.
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Affiliation(s)
- Robson Coutinho-Silva
- Programa de Imunobiologia, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro (UFRJ), Bloco G do CCS, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, 21941-590, Brazil,
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49
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Mueller P, Pieters J. Modulation of macrophage antimicrobial mechanisms by pathogenic mycobacteria. Immunobiology 2006; 211:549-56. [PMID: 16920493 DOI: 10.1016/j.imbio.2006.06.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2006] [Accepted: 06/06/2006] [Indexed: 01/13/2023]
Abstract
Tuberculosis remained a mysterious disease until Koch was able to demonstrate in the late 1800s that it was caused by a bacterium spread by aerosols, Mycobacterium tuberculosis. Today, tuberculosis still is a major health problem causing approximately 2 million deaths annually with about one third of the world's population being latently infected with M. tuberculosis. The secret of success for M. tuberculosis lies in its ability to persist inside host cells, the macrophages. Whereas macrophages are designed to destroy any incoming microbe, pathogenic mycobacteria have evolved strategies to survive within macrophages by preventing phagosome-lysosome fusion, thereby creating a niche that allows them to persist within an otherwise hostile environment. In this contribution, we discuss recent advances in our understanding of the interplay between the host and this pathogen that lead to survival of mycobacteria within macrophages.
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Affiliation(s)
- Philipp Mueller
- Biozentrum, Klingelbergstrasse 50, University of Basel, CH 4056 Basel, Switzerland
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50
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Charette SJ, Cosson P. Exocytosis of late endosomes does not directly contribute membrane to the formation of phagocytic cups or pseudopods in Dictyostelium. FEBS Lett 2006; 580:4923-8. [PMID: 16920105 DOI: 10.1016/j.febslet.2006.08.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2006] [Revised: 07/19/2006] [Accepted: 08/01/2006] [Indexed: 11/20/2022]
Abstract
Exocytosis of late endocytic compartments in Dictyostelium has mostly been studied by live microscopy. Here we show that this exocytosis is accompanied by a complete fusion of late endosomes with the plasma membrane resulting in the transient formation of membrane microdomains that can be visualized by immunofluorescence in fixed cells. This permitted to demonstrate that fusion of late endocytic compartments with the cell surface does not occur in regions of the plasma membrane engaged in the formation of pseudopods, macropinosomes or phagosomes. Our results propose that exocytosis of late endosomes and actin-driven membrane remodeling are mutually exclusive processes.
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Affiliation(s)
- Steve J Charette
- Université de Genève, Centre Médical Universitaire, Département de physiologie cellulaire et métabolisme, 1 rue Michel Servet, CH-1211 Geneva 4, Switzerland.
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