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Galais M, Pradel B, Vergne I, Robert-Hebmann V, Espert L, Biard-Piechaczyk M. [LAP (LC3-associated phagocytosis): phagocytosis or autophagy?]. Med Sci (Paris) 2019; 35:635-642. [PMID: 31532375 DOI: 10.1051/medsci/2019129] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Phagocytosis and macroautophagy, named here autophagy, are two essential mechanisms of lysosomal degradation of diverse cargos into membrane structures. Both mechanisms are involved in immune regulation and cell survival. However, phagocytosis triggers degradation of extracellular material whereas autophagy engulfs only cytoplasmic elements. Furthermore, activation and maturation of these two processes are different. LAP (LC3-associated phagocytosis) is a form of phagocytosis that uses components of the autophagy pathway. It can eliminate (i) pathogens, (ii) immune complexes, (iii) threatening neighbouring cells, dead or alive, and (iv) cell debris, such as POS (photoreceptor outer segment) and the midbody released at the end of mitosis. Cells have thus optimized their means of elimination of dangerous components by sharing some fundamental elements coming from the two main lysosomal degradation pathways.
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Affiliation(s)
- Mathilde Galais
- Institut de recherche en infectiologie de Montpellier (IRIM), Université de Montpellier, CNRS, 1919, route de Mende, 34293 Montpellier, France
| | - Baptiste Pradel
- Institut de recherche en infectiologie de Montpellier (IRIM), Université de Montpellier, CNRS, 1919, route de Mende, 34293 Montpellier, France
| | - Isabelle Vergne
- Institut de pharmacologie et de biologie structurale (IPBS), Université de Toulouse, CNRS, UPS, 205, route de Narbonne, 31400 Toulouse, France
| | - Véronique Robert-Hebmann
- Institut de recherche en infectiologie de Montpellier (IRIM), Université de Montpellier, CNRS, 1919, route de Mende, 34293 Montpellier, France
| | - Lucile Espert
- Institut de recherche en infectiologie de Montpellier (IRIM), Université de Montpellier, CNRS, 1919, route de Mende, 34293 Montpellier, France
| | - Martine Biard-Piechaczyk
- Institut de recherche en infectiologie de Montpellier (IRIM), Université de Montpellier, CNRS, 1919, route de Mende, 34293 Montpellier, France
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Ganesan S, Roy CR. Host cell depletion of tryptophan by IFNγ-induced Indoleamine 2,3-dioxygenase 1 (IDO1) inhibits lysosomal replication of Coxiella burnetii. PLoS Pathog 2019; 15:e1007955. [PMID: 31461509 PMCID: PMC6736304 DOI: 10.1371/journal.ppat.1007955] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 09/10/2019] [Accepted: 07/01/2019] [Indexed: 12/20/2022] Open
Abstract
Most intracellular pathogens that reside in a vacuole prevent transit of their compartment to lysosomal organelles. Effector mechanisms induced by the pro-inflammatory cytokine Interferon-gamma (IFNγ) can promote the delivery of pathogen-occupied vacuoles to lysosomes for proteolytic degradation and are therefore important for host defense against intracellular pathogens. The bacterial pathogen Coxiella burnetii is unique in that, transport to the lysosome is essential for replication. The bacterium modulates membrane traffic to create a specialized autophagolysosomal compartment called the Coxiella-containing vacuole (CCV). Importantly, IFNγ signaling inhibits intracellular replication of C. burnetii, raising the question of which IFNγ-activated mechanisms restrict replication of a lysosome-adapted pathogen. To address this question, siRNA was used to silence a panel of IFNγ-induced genes in HeLa cells to identify genes required for restriction of C. burnetii intracellular replication. This screen demonstrated that Indoleamine 2,3-dioxygenase 1 (IDO1) contributes to IFNγ-mediated restriction of C. burnetii. IDO1 is an enzyme that catabolizes cellular tryptophan to kynurenine metabolites thereby reducing tryptophan availability in cells. Cells deficient in IDO1 function were more permissive for C. burnetii replication when treated with IFNγ, and supplementing IFNγ-treated cells with tryptophan enhanced intracellular replication. Additionally, ectopic expression of IDO1 in host cells was sufficient to restrict replication of C. burnetii in the absence of IFNγ signaling. Using differentiated THP1 macrophage-like cells it was determined that IFNγ-activation resulted in IDO1 production, and that supplementation of IFNγ-activated THP1 cells with tryptophan enhanced C. burnetii replication. Thus, this study identifies IDO1 production as a key cell-autonomous defense mechanism that limits infection by C. burnetii, which suggests that peptides derived from hydrolysis of proteins in the CCV do not provide an adequate supply of tryptophan for bacterial replication.
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Affiliation(s)
- Sandhya Ganesan
- Department of Microbial Pathogenesis, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Craig R. Roy
- Department of Microbial Pathogenesis, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
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Khandia R, Dadar M, Munjal A, Dhama K, Karthik K, Tiwari R, Yatoo MI, Iqbal HMN, Singh KP, Joshi SK, Chaicumpa W. A Comprehensive Review of Autophagy and Its Various Roles in Infectious, Non-Infectious, and Lifestyle Diseases: Current Knowledge and Prospects for Disease Prevention, Novel Drug Design, and Therapy. Cells 2019; 8:cells8070674. [PMID: 31277291 PMCID: PMC6678135 DOI: 10.3390/cells8070674] [Citation(s) in RCA: 145] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 06/04/2019] [Accepted: 06/04/2019] [Indexed: 02/05/2023] Open
Abstract
Autophagy (self-eating) is a conserved cellular degradation process that plays important roles in maintaining homeostasis and preventing nutritional, metabolic, and infection-mediated stresses. Autophagy dysfunction can have various pathological consequences, including tumor progression, pathogen hyper-virulence, and neurodegeneration. This review describes the mechanisms of autophagy and its associations with other cell death mechanisms, including apoptosis, necrosis, necroptosis, and autosis. Autophagy has both positive and negative roles in infection, cancer, neural development, metabolism, cardiovascular health, immunity, and iron homeostasis. Genetic defects in autophagy can have pathological consequences, such as static childhood encephalopathy with neurodegeneration in adulthood, Crohn's disease, hereditary spastic paraparesis, Danon disease, X-linked myopathy with excessive autophagy, and sporadic inclusion body myositis. Further studies on the process of autophagy in different microbial infections could help to design and develop novel therapeutic strategies against important pathogenic microbes. This review on the progress and prospects of autophagy research describes various activators and suppressors, which could be used to design novel intervention strategies against numerous diseases and develop therapeutic drugs to protect human and animal health.
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Affiliation(s)
- Rekha Khandia
- Department of Genetics, Barkatullah University, Bhopal 462 026, Madhya Pradesh, India
| | - Maryam Dadar
- Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj 31975/148, Iran
| | - Ashok Munjal
- Department of Genetics, Barkatullah University, Bhopal 462 026, Madhya Pradesh, India.
| | - Kuldeep Dhama
- Division of Pathology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243 122, Uttar Pradesh, India.
| | - Kumaragurubaran Karthik
- Central University Laboratory, Tamil Nadu Veterinary and Animal Sciences University, Madhavaram Milk Colony, Chennai, Tamil Nadu 600051, India
| | - Ruchi Tiwari
- Department of Veterinary Microbiology and Immunology, College of Veterinary Sciences, UP Pandit Deen Dayal Upadhayay Pashu Chikitsa Vigyan Vishwavidyalay Evum Go-Anusandhan Sansthan (DUVASU), Mathura, Uttar Pradesh 281 001, India
| | - Mohd Iqbal Yatoo
- Sher-E-Kashmir University of Agricultural Sciences and Technology of Kashmir, Shalimar, Srinagar 190025, Jammu and Kashmir, India
| | - Hafiz M N Iqbal
- Tecnologico de Monterrey, School of Engineering and Sciences, Campus Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, N. L., CP 64849, Mexico
| | - Karam Pal Singh
- Division of Pathology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243 122, Uttar Pradesh, India
| | - Sunil K Joshi
- Department of Pediatrics, Division of Hematology, Oncology and Bone Marrow Transplantation, University of Miami School of Medicine, Miami, FL 33136, USA.
| | - Wanpen Chaicumpa
- Center of Research Excellence on Therapeutic Proteins and Antibody Engineering, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
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54
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LC3-associated phagocytosis: host defense and microbial response. Curr Opin Immunol 2019; 60:81-90. [PMID: 31247378 DOI: 10.1016/j.coi.2019.04.012] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 04/16/2019] [Indexed: 12/19/2022]
Abstract
The innate immune system has evolved to recognize diverse microbes and destroy them. At the same time, microbial pathogens undermine immunity to cause disease. Here, we highlight recent advances in understanding an antimicrobial pathway called LC3-associated phagocytosis (LAP), which combines features of autophagy with phagocytosis. Upon phagocytosis, many microbes, including bacteria, fungi, and parasites, are sequestered in an LC3-positive, single-membrane bound compartment, a hallmark of LAP. LAP depends upon NADPH oxidase activity at the incipient phagosome and culminates in lysosomal trafficking and microbial degradation. Most often LAP is an effective host defense, but some pathogens evade LAP or replicate successfully in this microenvironment. Here, we review how LAP targets microbial pathogens and strategies pathogens employ to circumvent LAP.
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Roberts AW, Popov LM, Mitchell G, Ching KL, Licht DJ, Golovkine G, Barton GM, Cox JS. Cas9 + conditionally-immortalized macrophages as a tool for bacterial pathogenesis and beyond. eLife 2019; 8:45957. [PMID: 31204998 PMCID: PMC6579556 DOI: 10.7554/elife.45957] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Accepted: 06/07/2019] [Indexed: 12/22/2022] Open
Abstract
Macrophages play critical roles in immunity, development, tissue repair, and cancer, but studies of their function have been hampered by poorly-differentiated tumor cell lines and genetically-intractable primary cells. Here we report a facile system for genome editing in non-transformed macrophages by differentiating ER-Hoxb8 myeloid progenitors from Cas9-expressing transgenic mice. These conditionally immortalized macrophages (CIMs) retain characteristics of primary macrophages derived from the bone marrow yet allow for easy genetic manipulation and a virtually unlimited supply of cells. We demonstrate the utility of this system for dissection of host genetics during intracellular bacterial infection using two important human pathogens: Listeria monocytogenes and Mycobacterium tuberculosis.
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Affiliation(s)
- Allison W Roberts
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Lauren M Popov
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Gabriel Mitchell
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Krystal L Ching
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Daniel J Licht
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Guillaume Golovkine
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Gregory M Barton
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Jeffery S Cox
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
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56
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Balla KM, Lažetić V, Troemel ER. Natural variation in the roles of C. elegans autophagy components during microsporidia infection. PLoS One 2019; 14:e0216011. [PMID: 31013330 PMCID: PMC6478341 DOI: 10.1371/journal.pone.0216011] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 04/11/2019] [Indexed: 12/14/2022] Open
Abstract
Natural genetic variation can determine the outcome of an infection, and often reflects the co-evolutionary battle between hosts and pathogens. We previously found that a natural variant of the nematode Caenorhabditis elegans from Hawaii (HW) has increased resistance against natural microsporidian pathogens in the Nematocida genus, when compared to the standard laboratory strain of N2. In particular, HW animals can clear infection, while N2 animals cannot. In addition, HW animals have lower levels of initial colonization of Nematocida inside intestinal cells, compared to N2. Here we investigate how this natural variation in resistance relates to autophagy. We found that there is much better targeting of autophagy-related machinery to parasites under conditions where they are cleared. In particular, ubiquitin targeting to Nematocida cells correlates very well with their subsequent clearance in terms of timing, host strain and age, as well as species of Nematocida. Furthermore, clearance correlates with targeting of the LGG-2/LC3 autophagy protein to parasite cells, with HW animals having much more efficient targeting of LGG-2 to parasite cells than N2 animals. Surprisingly, however, we found that LGG-2 is not required to clear infection. Instead, we found that LGG-2/LC3 regulates Nematocida colonization inside intestinal cells. Interestingly, LGG-2/LC3 regulates intracellular colonization only in the HW strain, and not in N2. Altogether these results demonstrate that there is natural genetic variation in an LGG-2-dependent process that regulates microsporidia colonization inside intestinal cells, although not microsporidia clearance.
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Affiliation(s)
- Keir M. Balla
- Division of Biological Sciences, University of California, San Diego, La Jolla, California, United States of America
| | - Vladimir Lažetić
- Division of Biological Sciences, University of California, San Diego, La Jolla, California, United States of America
| | - Emily R. Troemel
- Division of Biological Sciences, University of California, San Diego, La Jolla, California, United States of America
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Abstract
The Gram-positive pathogen Listeria monocytogenes is able to promote its entry into a diverse range of mammalian host cells by triggering plasma membrane remodeling, leading to bacterial engulfment. Upon cell invasion, L. monocytogenes disrupts its internalization vacuole and translocates to the cytoplasm, where bacterial replication takes place. Subsequently, L. monocytogenes uses an actin-based motility system that allows bacterial cytoplasmic movement and cell-to-cell spread. L. monocytogenes therefore subverts host cell receptors, organelles and the cytoskeleton at different infection steps, manipulating diverse cellular functions that include ion transport, membrane trafficking, post-translational modifications, phosphoinositide production, innate immune responses as well as gene expression and DNA stability.
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58
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Abstract
Classically, canonical autophagy has been considered a survival mechanism initiated in response to nutrient insufficiency. We now understand that autophagy functions in multiple scenarios where it is necessary to maintain homeostasis. Recent evidence has established that a variety of non-canonical functions for autophagy proteins are mechanistically and functionally distinct from autophagy. LC3-associated phagocytosis (LAP) is one such novel function for autophagy proteins and is a contributor to immune regulation and inflammatory responses across various cell and tissue types. Characterized by the conjugation of LC3 family proteins to phagosome membranes, LAP uses a portion of the canonical autophagy machinery, following ligation of surface receptors that recognize a variety of cargos including pathogens, dying cells, soluble ligands and protein aggregates. However, instead of affecting canonical autophagy, manipulation of the LAP pathway in vivo alters immune activation and inflammatory responses. In this Cell Science at a Glance article and the accompanying poster, we detail the divergence of this distinctive mechanism from that of canonical autophagy by comparing and contrasting shared and unique components of each pathway.
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Affiliation(s)
- Bradlee L Heckmann
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
- Cancer Biology Program, St. Jude Pediatric Comprehensive Cancer Center, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Douglas R Green
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
- Cancer Biology Program, St. Jude Pediatric Comprehensive Cancer Center, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
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59
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Chen C, Nguyen BN, Mitchell G, Margolis SR, Ma D, Portnoy DA. The Listeriolysin O PEST-like Sequence Co-opts AP-2-Mediated Endocytosis to Prevent Plasma Membrane Damage during Listeria Infection. Cell Host Microbe 2019; 23:786-795.e5. [PMID: 29902442 DOI: 10.1016/j.chom.2018.05.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 04/23/2018] [Accepted: 05/11/2018] [Indexed: 10/14/2022]
Abstract
Listeriolysin O (LLO) is a cholesterol-dependent cytolysin that mediates escape of Listeria monocytogenes from a phagosome, enabling growth of the bacteria in the host cell cytosol. LLO contains a PEST-like sequence that prevents it from killing infected cells, but the mechanism involved is unknown. We found that the LLO PEST-like sequence was necessary to mediate removal of LLO from the interior face of the plasma membrane, where it coalesces into discrete puncta. LLO interacts with Ap2a2, an adaptor protein involved in endocytosis, via its PEST-like sequence, and Ap2a2-dependent endocytosis is required to prevent LLO-induced cytotoxicity. An unrelated PEST-like sequence from a human G protein-coupled receptor (GPCR), which also interacts with Ap2a2, could functionally complement the PEST-like sequence in L. monocytogenes LLO. These data revealed that LLO co-opts the host endocytosis machinery to protect the integrity of the host plasma membrane during L. monocytogenes infection.
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Affiliation(s)
- Chen Chen
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Brittney N Nguyen
- Graduate Group in Microbiology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Gabriel Mitchell
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Shally R Margolis
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Darren Ma
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Daniel A Portnoy
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; School of Public Health, University of California, Berkeley, Berkeley, CA 94720, USA.
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60
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Roberts MF, Khan HM, Goldstein R, Reuter N, Gershenson A. Search and Subvert: Minimalist Bacterial Phosphatidylinositol-Specific Phospholipase C Enzymes. Chem Rev 2018; 118:8435-8473. [DOI: 10.1021/acs.chemrev.8b00208] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Mary F. Roberts
- Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | | | - Rebecca Goldstein
- Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | | | - Anne Gershenson
- Department of Biochemistry and Molecular Biology, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
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Spatial, Temporal, and Functional Assessment of LC3-Dependent Autophagy in Shigella flexneri Dissemination. Infect Immun 2018; 86:IAI.00134-18. [PMID: 29844234 DOI: 10.1128/iai.00134-18] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 05/22/2018] [Indexed: 12/21/2022] Open
Abstract
Shigella flexneri disseminates within the colonic mucosa by displaying actin-based motility in the cytosol of epithelial cells. Motile bacteria form membrane protrusions that project into adjacent cells and resolve into double-membrane vacuoles (DMVs) from which the bacteria escape, thereby achieving cell-to-cell spread. During dissemination, S. flexneri is targeted by LC3-dependent autophagy, a host cell defense mechanism against intracellular pathogens. The S. flexneri type III secretion system effector protein IcsB was initially proposed to counteract the recruitment of the LC3-dependent autophagy machinery to cytosolic bacteria. However, a recent study proposed that LC3 was recruited to bacteria in DMVs formed during cell-to-cell spread. To resolve the controversy and clarify the role of autophagy in S. flexneri infection, we tracked dissemination using live confocal microscopy and determined the spatial and temporal recruitment of LC3 to bacteria. This approach demonstrated that (i) LC3 was exclusively recruited to wild-type or icsB bacteria located in DMVs and (ii) the icsB mutant was defective in cell-to-cell spread due to failure to escape LC3-positive as well as LC3-negative DMVs. Failure of S. flexneri to escape DMVs correlated with late LC3 recruitment, suggesting that LC3 recruitment is the consequence and not the cause of DMV escape failure. Inhibition of autophagy had no positive impact on the spreading of wild-type or icsB mutant bacteria. Our results unambiguously demonstrate that IcsB is required for DMV escape during cell-to-cell spread, regardless of LC3 recruitment, and do not support the previously proposed notion that autophagy counters S. flexneri dissemination.
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Cheng MI, Chen C, Engström P, Portnoy DA, Mitchell G. Actin-based motility allows Listeria monocytogenes to avoid autophagy in the macrophage cytosol. Cell Microbiol 2018; 20:e12854. [PMID: 29726107 DOI: 10.1111/cmi.12854] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 04/03/2018] [Accepted: 04/23/2018] [Indexed: 12/23/2022]
Abstract
Listeria monocytogenes grows in the host cytosol and uses the surface protein ActA to promote actin polymerisation and mediate actin-based motility. ActA, along with two secreted bacterial phospholipases C, also mediates avoidance from autophagy, a degradative process that targets intracellular microbes. Although it is known that ActA prevents autophagic recognition of L. monocytogenes in epithelial cells by masking the bacterial surface with host factors, the relative roles of actin polymerisation and actin-based motility in autophagy avoidance are unclear in macrophages. Using pharmacological inhibition of actin polymerisation and a collection of actA mutants, we found that actin polymerisation prevented the colocalisation of L. monocytogenes with polyubiquitin, the autophagy receptor p62, and the autophagy protein LC3 during macrophage infection. In addition, the ability of L. monocytogenes to stimulate actin polymerisation promoted autophagy avoidance and growth in macrophages in the absence of phospholipases C. Time-lapse microscopy using green fluorescent protein-LC3 macrophages and a probe for filamentous actin showed that bacteria undergoing actin-based motility moved away from LC3-positive membranes. Collectively, these results suggested that although actin polymerisation protects the bacterial surface from autophagic recognition, actin-based motility allows escape of L. monocytogenes from autophagic membranes in the macrophage cytosol.
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Affiliation(s)
- Mandy I Cheng
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Chen Chen
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Patrik Engström
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Daniel A Portnoy
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.,School of Public Health, University of California, Berkeley, CA, USA
| | - Gabriel Mitchell
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
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