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Lehne F, Bogdan S. Swip-1 promotes exocytosis of glue granules in the exocrine Drosophila salivary gland. J Cell Sci 2023; 136:286884. [PMID: 36727484 PMCID: PMC10038153 DOI: 10.1242/jcs.260366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 01/27/2023] [Indexed: 02/03/2023] Open
Abstract
Exocytosis is a fundamental cellular process by which cells secrete cargos from their apical membrane into the extracellular lumen. Cargo release proceeds in sequential steps that depend on coordinated assembly and organization of an actin cytoskeletal network. Here, we identified the conserved actin-crosslinking protein Swip-1 as a novel regulator controlling exocytosis of glue granules in the Drosophila salivary gland. Real-time imaging revealed that Swip-1 is simultaneously recruited with F-actin onto secreting granules in proximity to the apical membrane. We observed that Swip-1 is rapidly cleared at the point of secretory vesicle fusion and colocalizes with actomyosin network around the fused vesicles. Loss of Swip-1 function impairs secretory cargo expulsion, resulting in strongly delayed secretion. Thus, our results uncover a novel role of Swip-1 in secretory vesicle compression and expulsion of cargo during regulated exocytosis. Remarkably, this function neither requires Ca2+ binding nor dimerization of Swip-1. Our data rather suggest that Swip-1 regulates actomyosin activity upstream of Rho-GTPase signaling to drive proper vesicle membrane crumpling and expulsion of cargo.
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Affiliation(s)
- Franziska Lehne
- Institute of Physiology and Pathophysiology, Department of Molecular Cell Physiology, Philipps-University Marburg, 35037 Marburg, Germany
| | - Sven Bogdan
- Institute of Physiology and Pathophysiology, Department of Molecular Cell Physiology, Philipps-University Marburg, 35037 Marburg, Germany
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2
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Khalili D, Kunc M, Herbrich S, Müller AM, Theopold U. Chitinase-like proteins promoting tumorigenesis through disruption of cell polarity via enlarged endosomal vesicles. Front Oncol 2023; 13:1170122. [PMID: 37188187 PMCID: PMC10175591 DOI: 10.3389/fonc.2023.1170122] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 04/05/2023] [Indexed: 05/17/2023] Open
Abstract
Introduction Chitinase-like proteins (CLPs) are associated with tissue-remodeling and inflammation but also with several disorders, including fibrosis, atherosclerosis, allergies, and cancer. However, CLP's role in tumors is far from clear. Methods Here, we utilize Drosophila melanogaster and molecular genetics to investigate the function of CLPs (imaginal disc growth factors; Idgf's) in RasV12 dysplastic salivary glands. Results and discussion We find one of the Idgf's members, Idgf3, is transcriptionally induced in a JNK-dependent manner via a positive feedback loop mediated by reactive oxygen species (ROS). Moreover, Idgf3 accumulates in enlarged endosomal vesicles (EnVs) that promote tumor progression by disrupting cytoskeletal organization. The process is mediated via the downstream component, aSpectrin, which localizes to the EnVs. Our data provide new insight into CLP function in tumors and identifies specific targets for tumor control.
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Kamalesh K, Scher N, Biton T, Schejter ED, Shilo BZ, Avinoam O. Exocytosis by vesicle crumpling maintains apical membrane homeostasis during exocrine secretion. Dev Cell 2021; 56:1603-1616.e6. [PMID: 34102104 PMCID: PMC8191493 DOI: 10.1016/j.devcel.2021.05.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 03/17/2021] [Accepted: 05/06/2021] [Indexed: 12/14/2022]
Abstract
Exocrine secretion commonly employs micron-scale vesicles that fuse to a limited apical surface, presenting an extreme challenge for maintaining membrane homeostasis. Using Drosophila melanogaster larval salivary glands, we show that the membranes of fused vesicles undergo actomyosin-mediated folding and retention, which prevents them from incorporating into the apical surface. In addition, the diffusion of proteins and lipids between the fused vesicle and the apical surface is limited. Actomyosin contraction and membrane crumpling are essential for recruiting clathrin-mediated endocytosis to clear the retained vesicular membrane. Finally, we also observe membrane crumpling in secretory vesicles of the mouse exocrine pancreas. We conclude that membrane sequestration by crumpling followed by targeted endocytosis of the vesicular membrane, represents a general mechanism of exocytosis that maintains membrane homeostasis in exocrine tissues that employ large secretory vesicles.
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Affiliation(s)
- Kumari Kamalesh
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel; Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Nadav Scher
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Tom Biton
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel; Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Eyal D Schejter
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Ben-Zion Shilo
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel.
| | - Ori Avinoam
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel.
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4
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de la Riva-Carrasco R, Perez-Pandolfo S, Suárez Freire S, Romero NM, Bhujabal Z, Johansen T, Wappner P, Melani M. The immunophilin Zonda controls regulated exocytosis in endocrine and exocrine tissues. Traffic 2021; 22:111-122. [PMID: 33336828 DOI: 10.1111/tra.12777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 12/15/2020] [Accepted: 12/15/2020] [Indexed: 11/30/2022]
Abstract
Exocytosis is a fundamental process in physiology, that ensures communication between cells, organs and even organisms. Hormones, neuropeptides and antibodies, among other cargoes are packed in exocytic vesicles that need to reach and fuse with the plasma membrane to release their content to the extracellular milieu. Hundreds of proteins participate in this process and several others in its regulation. We report here a novel component of the exocytic machinery, the Drosophila transmembrane immunophilin Zonda (Zda), previously found to participate in autophagy. Zda is highly expressed in secretory tissues, and regulates exocytosis in at least three of them: the ring gland, insulin-producing cells and the salivary gland. Using the salivary gland as a model system, we found that Zda is required at final steps of the exocytic process for fusion of secretory granules to the plasma membrane. In a genetic screen we identified the small GTPase RalA as a crucial regulator of secretory granule exocytosis that is required, similarly to Zda, for fusion between the secretory granule and the plasma membrane.
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Affiliation(s)
| | - Sebastián Perez-Pandolfo
- Laboratorio de Genética y Fisiología Molecular, Fundación Instituto Leloir, Buenos Aires, Argentina
| | - Sofía Suárez Freire
- Laboratorio de Genética y Fisiología Molecular, Fundación Instituto Leloir, Buenos Aires, Argentina
| | - Nuria M Romero
- Université Côte d'Azur, INRA, CNRS, Institut Sophia Agrobiotech, Sophia Antipolis, France
| | - Zambarlal Bhujabal
- Molecular Cancer Research Group, Department of Medical Biology, University of Tromsø-The Arctic University of Norway, Tromsø, Norway
| | - Terje Johansen
- Molecular Cancer Research Group, Department of Medical Biology, University of Tromsø-The Arctic University of Norway, Tromsø, Norway
| | - Pablo Wappner
- Laboratorio de Genética y Fisiología Molecular, Fundación Instituto Leloir, Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.,Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Mariana Melani
- Laboratorio de Genética y Fisiología Molecular, Fundación Instituto Leloir, Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
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5
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Loganathan R, Kim JH, Wells MB, Andrew DJ. Secrets of secretion-How studies of the Drosophila salivary gland have informed our understanding of the cellular networks underlying secretory organ form and function. Curr Top Dev Biol 2020; 143:1-36. [PMID: 33820619 DOI: 10.1016/bs.ctdb.2020.09.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Secretory organs are critical for organismal survival. Yet, the transcriptional regulatory mechanisms governing their development and maintenance remain unclear for most model secretory organs. The Drosophila embryonic salivary gland (SG) remedies this deficiency as one of the few organs wherein direct connections from the expression of the early patterning genes to cell specification to organ architecture and functional specialization can be made. Few other models of secretion can be accorded this distinction. Studies from the past three decades have made enormous strides in parsing out the roles of distinct transcription factors (TFs) that direct major steps in furnishing this secretory organ. In the first step of specifying the salivary gland, the activity of the Hox factors Sex combs reduced, Extradenticle, and Homothorax activate expression of fork head (fkh), sage, and CrebA, which code for the major suite of TFs that carry forward the task of organ building and maintenance. Then, in the second key step of building the SG, the program for cell fate maintenance and morphogenesis is deployed. Fkh maintains the secretory cell fate by regulating its own expression and that of sage and CrebA. Fkh and Sage maintain secretory cell viability by actively blocking apoptotic cell death. Fkh, along with two other TFs, Hkb and Rib, also coordinates organ morphogenesis, transforming two plates of precursor cells on the embryo surface into elongated internalized epithelial tubes. Acquisition of functional specialization, the third key step, is mediated by CrebA and Fkh working in concert with Sage and yet another TF, Sens. CrebA directly upregulates expression of all of the components of the secretory machinery as well as other genes (e.g., Xbp1) necessary for managing the physiological stress that inexorably accompanies high secretory load. Secretory cargo specificity is controlled by Sage and Sens in collaboration with Fkh. Investigations have also uncovered roles for various signaling pathways, e.g., Dpp signaling, EGF signaling, GPCR signaling, and cytoskeletal signaling, and their interactions within the gene regulatory networks that specify, build, and specialize the SG. Collectively, studies of the SG have expanded our knowledge of secretory dynamics, cell polarity, and cytoskeletal mechanics in the context of organ development and function. Notably, the embryonic SG has made the singular contribution as a model system that revealed the core function of CrebA in scaling up secretory capacity, thus, serving as the pioneer system in which the conserved roles of the mammalian Creb3/3L-family orthologues were first discovered.
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Affiliation(s)
- Rajprasad Loganathan
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Ji Hoon Kim
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Michael B Wells
- Idaho College of Osteopathic Medicine, Meridian, ID, United States
| | - Deborah J Andrew
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States.
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6
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Kokot H, Kokot B, Sebastijanović A, Voss C, Podlipec R, Zawilska P, Berthing T, Ballester-López C, Danielsen PH, Contini C, Ivanov M, Krišelj A, Čotar P, Zhou Q, Ponti J, Zhernovkov V, Schneemilch M, Doumandji Z, Pušnik M, Umek P, Pajk S, Joubert O, Schmid O, Urbančič I, Irmler M, Beckers J, Lobaskin V, Halappanavar S, Quirke N, Lyubartsev AP, Vogel U, Koklič T, Stoeger T, Štrancar J. Prediction of Chronic Inflammation for Inhaled Particles: the Impact of Material Cycling and Quarantining in the Lung Epithelium. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2003913. [PMID: 33073368 DOI: 10.1002/adma.202003913] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 08/22/2020] [Indexed: 06/11/2023]
Abstract
On a daily basis, people are exposed to a multitude of health-hazardous airborne particulate matter with notable deposition in the fragile alveolar region of the lungs. Hence, there is a great need for identification and prediction of material-associated diseases, currently hindered due to the lack of in-depth understanding of causal relationships, in particular between acute exposures and chronic symptoms. By applying advanced microscopies and omics to in vitro and in vivo systems, together with in silico molecular modeling, it is determined herein that the long-lasting response to a single exposure can originate from the interplay between the newly discovered nanomaterial quarantining and nanomaterial cycling between different lung cell types. This new insight finally allows prediction of the spectrum of lung inflammation associated with materials of interest using only in vitro measurements and in silico modeling, potentially relating outcomes to material properties for a large number of materials, and thus boosting safe-by-design-based material development. Because of its profound implications for animal-free predictive toxicology, this work paves the way to a more efficient and hazard-free introduction of numerous new advanced materials into our lives.
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Affiliation(s)
- Hana Kokot
- Department of Condensed Matter Physics, Jožef Stefan Institute, Ljubljana, 1000, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, 1000, Slovenia
| | - Boštjan Kokot
- Department of Condensed Matter Physics, Jožef Stefan Institute, Ljubljana, 1000, Slovenia
- Faculty of Natural Sciences and Mathematics, University of Maribor, Maribor, 2000, Slovenia
| | - Aleksandar Sebastijanović
- Department of Condensed Matter Physics, Jožef Stefan Institute, Ljubljana, 1000, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, 1000, Slovenia
| | - Carola Voss
- Institute of Lung Biology and Disease, Helmholtz Zentrum München, 85764, Neuherberg, Germany
| | - Rok Podlipec
- Department of Condensed Matter Physics, Jožef Stefan Institute, Ljubljana, 1000, Slovenia
- Ion Beam Center, Helmholtz-Zentrum Dresden-Rossendorf e.V., 01328, Dresden, Germany
| | - Patrycja Zawilska
- Department of Condensed Matter Physics, Jožef Stefan Institute, Ljubljana, 1000, Slovenia
| | - Trine Berthing
- National Research Centre for the Working Environment, Copenhagen Ø, 2100, Denmark
| | | | | | - Claudia Contini
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, London, W12 0BZ, UK
| | - Mikhail Ivanov
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, SE-10691, Sweden
| | - Ana Krišelj
- Department of Condensed Matter Physics, Jožef Stefan Institute, Ljubljana, 1000, Slovenia
| | - Petra Čotar
- Department of Condensed Matter Physics, Jožef Stefan Institute, Ljubljana, 1000, Slovenia
- Faculty of Mathematics and Physics, University of Ljubljana, Ljubljana, 1000, Slovenia
| | - Qiaoxia Zhou
- Institute of Lung Biology and Disease, Helmholtz Zentrum München, 85764, Neuherberg, Germany
- Department of Forensic Pathology, Sichuan University, Chengdu, 610065, China
| | - Jessica Ponti
- European Commission, Joint Research Centre (JRC), Ispra, 21027, Italy
| | - Vadim Zhernovkov
- Systems Biology Ireland, School of Medicine, University College Dublin, Belfield, Dublin, 4, Ireland
| | - Matthew Schneemilch
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, London, W12 0BZ, UK
| | - Zahra Doumandji
- Institut Jean Lamour, UMR CNRS 7198, Université de Lorraine, CNRS, IJL, Nancy, F-54000, France
| | - Mojca Pušnik
- Faculty of Pharmacy, University of Ljubljana, Ljubljana, 1000, Slovenia
| | - Polona Umek
- Department of Condensed Matter Physics, Jožef Stefan Institute, Ljubljana, 1000, Slovenia
| | - Stane Pajk
- Department of Condensed Matter Physics, Jožef Stefan Institute, Ljubljana, 1000, Slovenia
- Faculty of Pharmacy, University of Ljubljana, Ljubljana, 1000, Slovenia
| | - Olivier Joubert
- Institut Jean Lamour, UMR CNRS 7198, Université de Lorraine, CNRS, IJL, Nancy, F-54000, France
| | - Otmar Schmid
- Institute of Lung Biology and Disease, Helmholtz Zentrum München, 85764, Neuherberg, Germany
| | - Iztok Urbančič
- Department of Condensed Matter Physics, Jožef Stefan Institute, Ljubljana, 1000, Slovenia
| | - Martin Irmler
- Institute of Experimental Genetics, Helmholtz Zentrum München, 85764, Neuherberg, Germany
| | - Johannes Beckers
- Institute of Experimental Genetics, Helmholtz Zentrum München, 85764, Neuherberg, Germany
- German Center for Diabetes Research (DZD), 85764, Neuherberg, Germany
- Chair of Experimental Genetics, Center of Life and Food Sciences, Weihenstephan, Technische Universität München, 85354, Freising, Germany
| | - Vladimir Lobaskin
- School of Physics, University College Dublin, Belfield, Dublin, 4, Ireland
| | - Sabina Halappanavar
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, K1Y 0M1, Canada
| | - Nick Quirke
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, London, W12 0BZ, UK
| | - Alexander P Lyubartsev
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, SE-10691, Sweden
| | - Ulla Vogel
- National Research Centre for the Working Environment, Copenhagen Ø, 2100, Denmark
| | - Tilen Koklič
- Department of Condensed Matter Physics, Jožef Stefan Institute, Ljubljana, 1000, Slovenia
| | - Tobias Stoeger
- Institute of Lung Biology and Disease, Helmholtz Zentrum München, 85764, Neuherberg, Germany
| | - Janez Štrancar
- Department of Condensed Matter Physics, Jožef Stefan Institute, Ljubljana, 1000, Slovenia
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7
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Díaz JM, Dozois CM, Avelar-González FJ, Hernández-Cuellar E, Pokharel P, de Santiago AS, Guerrero-Barrera AL. The Vacuolating Autotransporter Toxin (Vat) of Escherichia coli Causes Cell Cytoskeleton Changes and Produces Non-lysosomal Vacuole Formation in Bladder Epithelial Cells. Front Cell Infect Microbiol 2020; 10:299. [PMID: 32670893 PMCID: PMC7332727 DOI: 10.3389/fcimb.2020.00299] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Accepted: 05/19/2020] [Indexed: 12/13/2022] Open
Abstract
Urinary tract infections (UTIs) affect more than 150 million people, with a cost of over 3.5 billion dollars, each year. Escherichia coli is associated with 70–80% of UTIs. Uropathogenic E. coli (UPEC) has virulence factors including adhesins, siderophores, and toxins that damage host cells. Vacuolating autotransporter toxin (Vat) is a member of serine protease autotransporter proteins of Enterobacteriaceae (SPATEs) present in some uropathogenic E. coli (UPEC) strains. Vat has been identified in 20–36% of UPEC and is present in almost 68% of urosepsis isolates. However, the mechanism of action of Vat on host cells is not well-known. Thus, in this study the effect of Vat in a urothelium model of bladder cells was investigated. Several toxin concentrations were tested for different time periods, resulting in 15–47% of cellular damage as measured by the LDH assay. Vat induced vacuole formation on the urothelium model in a time-dependent manner. Vat treatment showed loss of the intercellular contacts on the bladder cell monolayer, observed by Scanning Electron Microscopy. This was also shown using antibodies against ZO-1 and occludin by immunofluorescence. Additionally, changes in permeability of the epithelial monolayer was demonstrated with a fluorescence-based permeability assay. Cellular damage was also evaluated by the identification of cytoskeletal changes produced by Vat. Thus, after Vat treatment, cells presented F-actin distribution changes and loss of stress fibers in comparison with control cells. Vat also modified tubulin, but it was not found to affect Arp3 distribution. In order to find the nature of the vacuoles generated by Vat, the Lysotracker deep red fluorescent dye for the detection of acidic organelles was used. Cells treated with Vat showed generation of some vacuoles without acidic content. An ex vivo experiment with mouse bladder exposed to Vat demonstrated loss of integrity of the urothelium. In conclusion, Vat induced cellular damage, vacuole formation, and urothelial barrier dysregulation of bladder epithelial cells. Further studies are needed to elucidate the role of these vacuoles induced by Vat and their relationship with the pathogenesis of urinary tract infection.
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Affiliation(s)
- Juan Manuel Díaz
- Departamento de Morfología, Universidad Autónoma de Aguascalientes (UAA), Aguascalientes, Mexico
| | - Charles M Dozois
- Institut National de Recherche Scientifique (INRS)-Centre Armand-Fappier Santé Biotechnologie, Laval, QC, Canada
| | | | | | - Pravil Pokharel
- Institut National de Recherche Scientifique (INRS)-Centre Armand-Fappier Santé Biotechnologie, Laval, QC, Canada
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8
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Lattner J, Leng W, Knust E, Brankatschk M, Flores-Benitez D. Crumbs organizes the transport machinery by regulating apical levels of PI(4,5)P 2 in Drosophila. eLife 2019; 8:e50900. [PMID: 31697234 PMCID: PMC6881148 DOI: 10.7554/elife.50900] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 10/25/2019] [Indexed: 12/12/2022] Open
Abstract
An efficient vectorial intracellular transport machinery depends on a well-established apico-basal polarity and is a prerequisite for the function of secretory epithelia. Despite extensive knowledge on individual trafficking pathways, little is known about the mechanisms coordinating their temporal and spatial regulation. Here, we report that the polarity protein Crumbs is essential for apical plasma membrane phospholipid-homeostasis and efficient apical secretion. Through recruiting βHeavy-Spectrin and MyosinV to the apical membrane, Crumbs maintains the Rab6-, Rab11- and Rab30-dependent trafficking and regulates the lipid phosphatases Pten and Ocrl. Crumbs knock-down results in increased apical levels of PI(4,5)P2 and formation of a novel, Moesin- and PI(4,5)P2-enriched apical membrane sac containing microvilli-like structures. Our results identify Crumbs as an essential hub required to maintain the organization of the apical membrane and the physiological activity of the larval salivary gland.
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Affiliation(s)
- Johanna Lattner
- Max-Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG)DresdenGermany
| | - Weihua Leng
- Max-Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG)DresdenGermany
| | - Elisabeth Knust
- Max-Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG)DresdenGermany
| | - Marko Brankatschk
- The Biotechnological Center of the TU Dresden (BIOTEC)DresdenGermany
| | - David Flores-Benitez
- Max-Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG)DresdenGermany
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9
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Reynolds HM, Zhang L, Tran DT, Ten Hagen KG. Tango1 coordinates the formation of endoplasmic reticulum/Golgi docking sites to mediate secretory granule formation. J Biol Chem 2019; 294:19498-19510. [PMID: 31690624 DOI: 10.1074/jbc.ra119.011063] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 10/30/2019] [Indexed: 11/06/2022] Open
Abstract
Regulated secretion is a conserved process occurring across diverse cells and tissues. Current models suggest that the conserved cargo receptor Tango1 mediates the packaging of collagen into large coat protein complex II (COPII) vesicles that move from the endoplasmic reticulum (ER) to the Golgi apparatus. However, how Tango1 regulates the formation of COPII carriers and influences the secretion of other cargo remains unknown. Here, through high-resolution imaging of Tango1, COPII, Golgi, and secretory cargo (mucins) in Drosophila larval salivary glands, we found that Tango1 forms ring-like structures that mediate the formation of COPII rings rather than vesicles. These COPII rings act as docking sites for the cis-Golgi. Moreover, we observed nascent secretory mucins emerging from the Golgi side of these Tango1-COPII-Golgi complexes, suggesting that these structures represent functional docking sites/fusion points between the ER exit sites and the Golgi. Loss of Tango1 disrupted the formation of COPII rings, the association of COPII with the cis-Golgi, mucin O-glycosylation, and secretory granule biosynthesis. Additionally, we identified a Tango1 self-association domain that is essential for formation of this structure. Our results provide evidence that Tango1 organizes an interaction site where secretory cargo is efficiently transferred from the ER to Golgi and then to secretory vesicles. These findings may explain how the loss of Tango1 can influence Golgi/ER morphology and affect the secretion of diverse proteins across many tissues.
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Affiliation(s)
- Hayley M Reynolds
- Developmental Glycobiology Section, NIDCR, National Institutes of Health, Bethesda, Maryland 20892-4370
| | - Liping Zhang
- Developmental Glycobiology Section, NIDCR, National Institutes of Health, Bethesda, Maryland 20892-4370
| | - Duy T Tran
- NIDCR Imaging Core, NIDCR, National Institutes of Health, Bethesda, Maryland 20892-4370
| | - Kelly G Ten Hagen
- Developmental Glycobiology Section, NIDCR, National Institutes of Health, Bethesda, Maryland 20892-4370
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10
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Furber KL, Backlund PS, Yergey AL, Coorssen JR. Unbiased Thiol-Labeling and Top-Down Proteomic Analyses Implicate Multiple Proteins in the Late Steps of Regulated Secretion. Proteomes 2019; 7:proteomes7040034. [PMID: 31569819 PMCID: PMC6958363 DOI: 10.3390/proteomes7040034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 09/20/2019] [Accepted: 09/23/2019] [Indexed: 12/12/2022] Open
Abstract
Regulated exocytosis enables temporal and spatial control over the secretion of biologically active compounds; however, the mechanism by which Ca2+ modulates different stages of exocytosis is still poorly understood. For an unbiased, top-down proteomic approach, select thiol- reactive reagents were used to investigate this process in release-ready native secretory vesicles. We previously characterized a biphasic effect of these reagents on Ca2+-triggered exocytosis: low doses potentiated Ca2+ sensitivity, whereas high doses inhibited Ca2+ sensitivity and extent of vesicle fusion. Capitalizing on this novel potentiating effect, we have now identified fluorescent thiol- reactive reagents producing the same effects: Lucifer yellow iodoacetamide, monobromobimane, and dibromobimane. Top-down proteomic analyses of fluorescently labeled proteins from total and cholesterol-enriched vesicle membrane fractions using two-dimensional gel electrophoresis coupled with mass spectrometry identified several candidate targets, some of which have been previously linked to the late steps of regulated exocytosis and some of which are novel. Initial validation studies indicate that Rab proteins are involved in the modulation of Ca2+ sensitivity, and thus the efficiency of membrane fusion, which may, in part, be linked to their previously identified upstream roles in vesicle docking.
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Affiliation(s)
- Kendra L Furber
- Northern Medical Program, University of Northern British Columbia, Prince George, BC V2N 4Z9, Canada.
| | - Peter S Backlund
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Alfred L Yergey
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Jens R Coorssen
- Department of Health Sciences, Faculty of Applied Health Sciences and Department of Biological Sciences, Faculty of Mathematics & Science, Brock University, St. Catharines, ON L2S 3A1, Canada.
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11
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Ebrahim S, Weigert R. Intravital microscopy in mammalian multicellular organisms. Curr Opin Cell Biol 2019; 59:97-103. [PMID: 31125832 PMCID: PMC6726551 DOI: 10.1016/j.ceb.2019.03.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 03/25/2019] [Accepted: 03/29/2019] [Indexed: 12/22/2022]
Abstract
Imaging subcellular processes in live animals is no longer a dream. The development of Intravital Subcellular Microscopy (ISMic) combined with the astounding repertoire of available mouse models makes it possible to investigate processes such as membrane trafficking in mammalian living tissues under native conditions. This has provided the unique opportunity to answer questions that cannot be otherwise addressed in reductionist model systems and to link cell biology to tissue pathophysiology.
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Affiliation(s)
- Seham Ebrahim
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Dr. Rm 2050B, Bethesda, MD, 20892, USA
| | - Roberto Weigert
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Dr. Rm 2050B, Bethesda, MD, 20892, USA.
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12
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Vogt EJ, Tokuhiro K, Guo M, Dale R, Yang G, Shin SW, Movilla MJ, Shroff H, Dean J. Anchoring cortical granules in the cortex ensures trafficking to the plasma membrane for post-fertilization exocytosis. Nat Commun 2019; 10:2271. [PMID: 31118423 PMCID: PMC6531442 DOI: 10.1038/s41467-019-10171-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 04/24/2019] [Indexed: 01/13/2023] Open
Abstract
Following fertilization, cortical granules exocytose ovastacin, a metalloendopeptidase that cleaves ZP2 in the zona pellucida surrounding mouse eggs to prevent additional sperm binding. Using high- and super-resolution imaging with ovastacinmCherry as a fluorescent marker, we characterize cortical granule dynamics at single granule resolution in transgenic mouse eggs. Newly-developed imaging protocols provide an unprecedented view of vesicular dynamics near the plasma membrane in mouse eggs. We discover that cortical granule anchoring in the cortex is dependent on maternal MATER and document that myosin IIA is required for biphasic trafficking to the plasma membrane. We observe local clearance of cortical actin during exocytosis and determine that pharmacologic or genetic disruption of trafficking to the plasma membrane impairs secretion of cortical granules and results in polyspermy. Thus, the regulation of cortical granule dynamics at the cortex-plasma membrane interface is critical for exocytosis and the post-fertilization block to sperm binding that ensures monospermic fertilization.
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Affiliation(s)
- Edgar-John Vogt
- Laboratory of Cellular and Developmental Biology, NIDDK, National Institutes of Health, Bethesda, MD, 20892, USA
- Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Keizo Tokuhiro
- Laboratory of Cellular and Developmental Biology, NIDDK, National Institutes of Health, Bethesda, MD, 20892, USA
- Department of Genome Editing, Institute of Biomedical Science, Kansai Medical University, 2-5-1 Shinmachi, Hirakata, Osaka, 573-1010, Japan
| | - Min Guo
- Section on High Resolution Optical Imaging, NIBIB, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Ryan Dale
- Laboratory of Cellular and Developmental Biology, NIDDK, National Institutes of Health, Bethesda, MD, 20892, USA
- Bioinformatics and Scientific Programming Core, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Guanghui Yang
- Laboratory of Cellular and Developmental Biology, NIDDK, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Seung-Wook Shin
- Laboratory of Cellular and Developmental Biology, NIDDK, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Maria Jimenez Movilla
- Department of Cell Biology and Histology, Medical School, University of Murcia, IMIB, 30100, Murcia, Spain
| | - Hari Shroff
- Section on High Resolution Optical Imaging, NIBIB, National Institutes of Health, Bethesda, MD, 20892, USA
- Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Jurrien Dean
- Laboratory of Cellular and Developmental Biology, NIDDK, National Institutes of Health, Bethesda, MD, 20892, USA.
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13
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Klein O, Sagi-Eisenberg R. Anaphylactic Degranulation of Mast Cells: Focus on Compound Exocytosis. J Immunol Res 2019; 2019:9542656. [PMID: 31011586 PMCID: PMC6442490 DOI: 10.1155/2019/9542656] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Accepted: 12/26/2018] [Indexed: 01/15/2023] Open
Abstract
Anaphylaxis is a notorious type 2 immune response which may result in a systemic response and lead to death. A precondition for the unfolding of the anaphylactic shock is the secretion of inflammatory mediators from mast cells in response to an allergen, mostly through activation of the cells via the IgE-dependent pathway. While mast cells are specialized secretory cells that can secrete through a variety of exocytic modes, the most predominant mode exerted by the mast cell during anaphylaxis is compound exocytosis-a specialized form of regulated exocytosis where secretory granules fuse to one another. Here, we review the modes of regulated exocytosis in the mast cell and focus on compound exocytosis. We review historical landmarks in the research of compound exocytosis in mast cells and the methods available for investigating compound exocytosis. We also review the molecular mechanisms reported to underlie compound exocytosis in mast cells and expand further with reviewing key findings from other cell types. Finally, we discuss the possible reasons for the mast cell to utilize compound exocytosis during anaphylaxis, the conflicting evidence in different mast cell models, and the open questions in the field which remain to be answered.
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Affiliation(s)
- Ofir Klein
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ronit Sagi-Eisenberg
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
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14
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Ji S, Samara NL, Revoredo L, Zhang L, Tran DT, Muirhead K, Tabak LA, Ten Hagen KG. A molecular switch orchestrates enzyme specificity and secretory granule morphology. Nat Commun 2018; 9:3508. [PMID: 30158631 PMCID: PMC6115407 DOI: 10.1038/s41467-018-05978-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 08/01/2018] [Indexed: 12/22/2022] Open
Abstract
Regulated secretion is an essential process where molecules destined for export are directed to membranous secretory granules, where they undergo packaging and maturation. Here, we identify a gene (pgant9) that influences the structure and shape of secretory granules within the Drosophila salivary gland. Loss of pgant9, which encodes an O-glycosyltransferase, results in secretory granules with an irregular, shard-like morphology, and altered glycosylation of cargo. Interestingly, pgant9 undergoes a splicing event that acts as a molecular switch to alter the charge of a loop controlling access to the active site of the enzyme. The splice variant with the negatively charged loop glycosylates the positively charged secretory cargo and rescues secretory granule morphology. Our study highlights a mechanism for dictating substrate specificity within the O-glycosyltransferase enzyme family. Moreover, our in vitro and in vivo studies suggest that the glycosylation status of secretory cargo influences the morphology of maturing secretory granules.
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Affiliation(s)
- Suena Ji
- Developmental Glycobiology Section, NIDCR, National Institutes of Health, 30 Convent Drive, Bethesda, MD, 20892-4370, USA
| | - Nadine L Samara
- Section on Biological Chemistry, NIDCR, National Institutes of Health, 30 Convent Drive, Bethesda, MD, 20892-4370, USA
| | - Leslie Revoredo
- Developmental Glycobiology Section, NIDCR, National Institutes of Health, 30 Convent Drive, Bethesda, MD, 20892-4370, USA
| | - Liping Zhang
- Developmental Glycobiology Section, NIDCR, National Institutes of Health, 30 Convent Drive, Bethesda, MD, 20892-4370, USA
| | - Duy T Tran
- Section on Biological Chemistry, NIDCR, National Institutes of Health, 30 Convent Drive, Bethesda, MD, 20892-4370, USA
| | - Kayla Muirhead
- Developmental Glycobiology Section, NIDCR, National Institutes of Health, 30 Convent Drive, Bethesda, MD, 20892-4370, USA
| | - Lawrence A Tabak
- Section on Biological Chemistry, NIDCR, National Institutes of Health, 30 Convent Drive, Bethesda, MD, 20892-4370, USA
| | - Kelly G Ten Hagen
- Developmental Glycobiology Section, NIDCR, National Institutes of Health, 30 Convent Drive, Bethesda, MD, 20892-4370, USA.
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15
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Yokawa S, Suzuki T, Hayashi A, Inouye S, Inoh Y, Furuno T. Video-Rate Bioluminescence Imaging of Degranulation of Mast Cells Attached to the Extracellular Matrix. Front Cell Dev Biol 2018; 6:74. [PMID: 30042943 PMCID: PMC6048188 DOI: 10.3389/fcell.2018.00074] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 06/22/2018] [Indexed: 11/13/2022] Open
Abstract
Degranulation refers to the secretion of inflammatory mediators, such as histamine, serotonin, and proteases, that are stored within the granules of mast cells and that trigger allergic reactions. The amount of these released mediators has been measured biochemically using cell mass. To investigate degranulation in living single cells, fluorescence microscopy has traditionally been used to observe the disappearance of granules and the appearance of these discharged granules within the plasma membrane by membrane fusion and the movement of granules inside the cells. Here, we developed a method of video-rate bioluminescence imaging to directly detect degranulation from a single mast cell by measuring luminescence activity derived from the enzymatic reaction between Gaussia luciferase (GLase) and its substrate coelenterazine. The neuropeptide Y (NPY), which was reported to colocalize with serotonin in the secretory granules, fused to GLase (NPY-GLase) was efficiently expressed in rat basophilic leukemia (RBL-2H3) cells, a mast-cell line, using a preferred human codon-optimized gene. Bioluminescence imaging analysis of RBL-2H3 cells expressing NPY-GLase and adhered on a glass-bottomed dish showed that the luminescence signals from the resting cells were negligible, while the luminescence signals of the secreted NPY-GLase were repeatedly detected after the addition of an antigen. In addition, this imaging method was applicable for observing degranulation in RBL-2H3 cells that adhered to the extracellular matrix (ECM). These results indicated that video-rate bioluminescence imaging using GLase will be a useful tool for detecting degranulation in single mast cells adhered to a variety of ECM proteins.
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Affiliation(s)
- Satoru Yokawa
- School of Pharmacy, Aichi Gakuin University, Nagoya, Japan
| | | | - Ayumi Hayashi
- School of Pharmacy, Aichi Gakuin University, Nagoya, Japan
| | - Satoshi Inouye
- Yokohama Research Center, JNC Corporation, Yokohama, Japan
| | - Yoshikazu Inoh
- School of Pharmacy, Aichi Gakuin University, Nagoya, Japan
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16
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Segal D, Zaritsky A, Schejter ED, Shilo BZ. Feedback inhibition of actin on Rho mediates content release from large secretory vesicles. J Cell Biol 2018; 217:1815-1826. [PMID: 29496739 PMCID: PMC5940311 DOI: 10.1083/jcb.201711006] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 12/24/2017] [Accepted: 01/30/2018] [Indexed: 12/02/2022] Open
Abstract
This work identified a cycle of actin assembly and disassembly in large secretory vesicles of Drosophila salivary glands. Actin disassembly is triggered by actin-dependent recruitment of a RhoGAP protein and is essential for the contractility of the vesicle, leading to content release to the lumen. Secretion of adhesive glycoproteins to the lumen of Drosophila melanogaster larval salivary glands is performed by contraction of an actomyosin network assembled around large secretory vesicles, after their fusion to the apical membranes. We have identified a cycle of actin coat nucleation and disassembly that is independent of myosin. Recruitment of active Rho1 to the fused vesicle triggers activation of the formin Diaphanous and actin nucleation. This leads to actin-dependent localization of a RhoGAP protein that locally shuts off Rho1, promoting disassembly of the actin coat. When contraction of vesicles is blocked, the strict temporal order of the recruited elements generates repeated oscillations of actin coat formation and disassembly. Interestingly, different blocks to actin coat disassembly arrested vesicle contraction, indicating that actin turnover is an integral part of the actomyosin contraction cycle. The capacity of F-actin to trigger a negative feedback on its own production may be widely used to coordinate a succession of morphogenetic events or maintain homeostasis.
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Affiliation(s)
- Dagan Segal
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Assaf Zaritsky
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel.,Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX
| | - Eyal D Schejter
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Ben-Zion Shilo
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
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17
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Sparvoli D, Richardson E, Osakada H, Lan X, Iwamoto M, Bowman GR, Kontur C, Bourland WA, Lynn DH, Pritchard JK, Haraguchi T, Dacks JB, Turkewitz AP. Remodeling the Specificity of an Endosomal CORVET Tether Underlies Formation of Regulated Secretory Vesicles in the Ciliate Tetrahymena thermophila. Curr Biol 2018; 28:697-710.e13. [PMID: 29478853 DOI: 10.1016/j.cub.2018.01.047] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 12/09/2017] [Accepted: 01/17/2018] [Indexed: 12/14/2022]
Abstract
In the endocytic pathway of animals, two related complexes, called CORVET (class C core vacuole/endosome transport) and HOPS (homotypic fusion and protein sorting), act as both tethers and fusion factors for early and late endosomes, respectively. Mutations in CORVET or HOPS lead to trafficking defects and contribute to human disease, including immune dysfunction. HOPS and CORVET are conserved throughout eukaryotes, but remarkably, in the ciliate Tetrahymena thermophila, the HOPS-specific subunits are absent, while CORVET-specific subunits have proliferated. VPS8 (vacuolar protein sorting), a CORVET subunit, expanded to 6 paralogs in Tetrahymena. This expansion correlated with loss of HOPS within a ciliate subgroup, including the Oligohymenophorea, which contains Tetrahymena. As uncovered via forward genetics, a single VPS8 paralog in Tetrahymena (VPS8A) is required to synthesize prominent secretory granules called mucocysts. More specifically, Δvps8a cells fail to deliver a subset of cargo proteins to developing mucocysts, instead accumulating that cargo in vesicles also bearing the mucocyst-sorting receptor Sor4p. Surprisingly, although this transport step relies on CORVET, it does not appear to involve early endosomes. Instead, Vps8a associates with the late endosomal/lysosomal marker Rab7, indicating that target specificity switching occurred in CORVET subunits during the evolution of ciliates. Mucocysts belong to a markedly diverse and understudied class of protist secretory organelles called extrusomes. Our results underscore that biogenesis of mucocysts depends on endolysosomal trafficking, revealing parallels with invasive organelles in apicomplexan parasites and suggesting that a wide array of secretory adaptations in protists, like in animals, depend on mechanisms related to lysosome biogenesis.
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Affiliation(s)
- Daniela Sparvoli
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, USA
| | | | - Hiroko Osakada
- Advanced ICT Research Institute, National Institute of Information and Communications Technology (NICT), Kobe 651-2492, Japan
| | - Xun Lan
- Department of Genetics, Stanford University, Stanford, CA 94305, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA
| | - Masaaki Iwamoto
- Advanced ICT Research Institute, National Institute of Information and Communications Technology (NICT), Kobe 651-2492, Japan
| | - Grant R Bowman
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, USA
| | - Cassandra Kontur
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, USA
| | - William A Bourland
- Department of Biological Sciences, Boise State University, Boise, ID 83725-1515, USA
| | - Denis H Lynn
- Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Jonathan K Pritchard
- Department of Genetics, Stanford University, Stanford, CA 94305, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA; Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Tokuko Haraguchi
- Advanced ICT Research Institute, National Institute of Information and Communications Technology (NICT), Kobe 651-2492, Japan; Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan
| | - Joel B Dacks
- Department of Cell Biology, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Aaron P Turkewitz
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, USA.
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