Entamoeba Histolytica
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CD2 Molecules Redistribute to the Uropod During T Cell Scanning: Implications for Cellular Activation and Immune Surveillance
CD2 molecules redistribute to the uropod during T cell scanning: Implications for cellular activation and immune surveillance Elena V. Tibaldi*†, Ravi Salgia†‡, and Ellis L. Reinherz*†§ *Laboratory of Immunobiology and ‡Division of Adult Oncology, Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, and †Department of Medicine, Harvard Medical School, Boston, MA 02115 Communicated by Stuart F. Schlossman, Dana-Farber Cancer Institute, Boston, MA, April 9, 2002 (received for review February 14, 2002) Dynamic binding between CD2 and CD58 counter-receptors on op- cells, whereas its counter-receptor CD58 is expressed on a posing cells optimizes immune recognition through stabilization of diverse array of nucleated and non-nucleated cells including cell–cell contact and juxtaposition of surface membranes at a distance APCs and stromal cells (reviewed in refs. 11 and 12). CD2 suitable for T cell receptor–ligand interaction. Digitized time-lapse functions in both T cell adhesion and activation processes (13). Ϸ differential interference contrast and immunofluorescence micros- Of note, the weak affinity of the CD2-CD58 interaction (Kd copy on living cells now show that this binding also induces T cell 1 M) is associated with remarkably fast on and off rates that polarization. Moreover, CD2 can facilitate motility of T cells along foster rapid and extensive exchange between CD2 and CD58 antigen-presenting cells via a movement referred to as scanning. Both partners on opposing cell surfaces (14–16). These biophysical activated CD4 and CD8 T cells are able to scan antigen-presenting cells characteristics are reminiscent of the selectin–ligand interactions surfaces in the absence of cognate antigen. -
Unique PKD Like Protein Kinase in Entamoeba Histolytica Regulates Vital Actin Mediated 2 Processes 3 4 Mithu Baidya, Santoshi Nayak, Amit K
bioRxiv preprint doi: https://doi.org/10.1101/677500; this version posted June 20, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 1 Unique PKD like protein kinase in Entamoeba histolytica regulates vital actin mediated 2 processes 3 4 Mithu Baidya, Santoshi Nayak, Amit K. Das, Sudip Kumar Ghosh# 5 6 Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 7 721 302, India. 8 #Address Correspondence to Sudip K. Ghosh, [email protected] 9 Telephone no: (+91) 3222 283768 Fax: (+91) 3222 278707 10 11 12 Abstract 13 Entamoeba histolytica causes widespread amoebiasis in humans. Multiple lines of emerging 14 evidence have identified a repertoire of proteins involved in the process of erythrophagocytosis. 15 However, the early initiation of the erythrophagosome at the site of erythrocyte's attachment is 16 not well understood. Here in our study we have identified and characterized a small Protein kinase 17 D like protein (EhPKDL) in Eh, which nucleates actin polymerization and thus mediates many vital 18 processes in Eh including erythrophagocytosis. Following multiple biochemical and biophysical 19 approaches, we have characterized EhPKDL and have shown that EhPKDL can indeed interact and 20 prime the nucleation of monomeric actin for polymerization. Furthermore, we went on to 21 demonstrate the vitality of the EhPKDL in major actin-mediated processes like capping, motility, 22 and erythrophagocytosis following knockdown of EhPKDL in the cellular context. Our study thus 23 provides novel insights into the early actin nucleation in Eh and thus bridges the gap with our 24 previous understanding of the assembly of erythrophagosomes. -
A Single Class II Myosin Modulates T Cell Motility and Stopping, but Not Synapse Formation
ARTICLES A single class II myosin modulates T cell motility and stopping, but not synapse formation Jordan Jacobelli1, Stephen A Chmura1, Denis B Buxton2, Mark M Davis3 & Matthew F Krummel1 Upon encountering an antigen, motile T cells stop crawling, change morphology and ultimately form an ‘immunological synapse’. Although myosin motors are thought to mediate various aspects of this process, the molecules involved and their exact roles are not defined. Here we show that nonmuscle myosin heavy chain IIA, or MyH9, is the only class II myosin expressed in T cells and is associated with the uropod during crawling. MyH9 function is required for maintenance of the uropod and for T cell motility but is dispensable for synapse formation. Phosphorylation of MyH9 in its multimerization domain by T cell receptor–generated signals indicates that inactivation of this motor may be a key step in the ‘stop’ response during http://www.nature.com/natureimmunology antigen recognition. T lymphocytes circulate through vasculature into peripheral lym- signaling10. Over time, these microclusters coalesce into a charac- phoid tissues, scanning antigen-presenting cells (APCs) for pep- teristic mature synapse, defined by a central core of TCR-CD3 com- tide–major histocompatibility complex (MHC) ligands for their T plexes surrounded by a ring of adhesion molecules11,12. The cell receptors (TCRs). After leaving the vasculature, T cells acquire a MTOC, formerly in the uropod, translocates to the contact site13. polarized morphology and initiate crawling, probably as a result of In this process, the nucleus is displaced away from the nascent chemotactic stimuli, earlier activating stimuli or both1–3. -
Non-Muscle Myosin 2A (NM2A): Structure, Regulation and Function
cells Review Non-Muscle Myosin 2A (NM2A): Structure, Regulation and Function Cláudia Brito 1,2 and Sandra Sousa 1,* 1 Group of Cell Biology of Bacterial Infections, i3S-Instituto de Investigação e Inovação em Saúde, IBMC, Universidade do Porto, 4200-135 Porto, Portugal; [email protected] 2 Programa Doutoral em Biologia Molecular e Celular (MCBiology), Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4099-002 Porto, Portugal * Correspondence: [email protected] Received: 19 May 2020; Accepted: 29 June 2020; Published: 1 July 2020 Abstract: Non-muscle myosin 2A (NM2A) is a motor cytoskeletal enzyme with crucial importance from the early stages of development until adulthood. Due to its capacity to convert chemical energy into force, NM2A powers the contraction of the actomyosin cytoskeleton, required for proper cell division, adhesion and migration, among other cellular functions. Although NM2A has been extensively studied, new findings revealed that a lot remains to be discovered concerning its spatiotemporal regulation in the intracellular environment. In recent years, new functions were attributed to NM2A and its activity was associated to a plethora of illnesses, including neurological disorders and infectious diseases. Here, we provide a concise overview on the current knowledge regarding the structure, the function and the regulation of NM2A. In addition, we recapitulate NM2A-associated diseases and discuss its potential as a therapeutic target. Keywords: non-muscle myosin 2A (NM2A); NM2A activity regulation; NM2A filament assembly; actomyosin cytoskeleton; cell migration; cell adhesion; plasma membrane blebbing 1. Superfamily of Myosins The cell cytoskeleton is an interconnected and dynamic network of filaments essential for intracellular organization and cell shape maintenance. -
Segregation of Leading-Edge and Uropod Components Into Specific Lipid Rafts During T Cell Polarization
Segregation of leading-edge and uropod components into specific lipid rafts during T cell polarization Concepcio´ nGo´ mez-Mouto´ n*, Jose Luis Abad*, Emilia Mira*, Rosa Ana Lacalle*, Eduard Gallardo†, Sonia Jime´ nez-Baranda*, Isabel Illa†, Antonio Bernad*, Santos Man˜ es*‡, and Carlos Marti´nez-A.* *Department of Immunology and Oncology, Centro Nacional de Biotecnologı´a,Consejo Superior de Investigaciones Cientı´ficas,Universidad Auto´noma de Madrid, Cantoblanco, E-28049 Madrid, Spain; and †Laboratorio de Neurologı´aExperimental, Santa Creu i Sant Pau Hospital, 08025 Barcelona, Spain Edited by Kai Simons, Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany, and approved June 11, 2001 (received for review April 2, 2001) Redistribution of specialized molecules in migrating cells develops CCR5, and other raft-associated proteins accumulate preferentially asymmetry between two opposite cell poles, the leading edge and at the leading lamella of migrating cells (4). Modification of the uropod. We show that acquisition of a motile phenotype in T raft-located proteins such that they no longer associate with rafts lymphocytes results in the asymmetric redistribution of ganglioside inhibits their asymmetric redistribution. The functional role of GM3- and GM1-enriched raft domains to the leading edge and to the asymmetric raft redistribution is shown in this article, as membrane uropod, respectively. This segregation to each cell pole parallels the cholesterol depletion impairs cell polarization and chemotaxis. specific redistribution of membrane proteins associated to each raft Cholesterol-depleted cells showed isotropic pseudopodial protru- subfraction. Our data suggest that raft partitioning is a major deter- sion, suggesting that raft redistribution is needed for location- minant for protein redistribution in polarized T cells, as ectopic specific induction of pseudopod protrusion during cell polarization. -
Cross-Talk Between Shigella and Cells of the Adaptive Immunity: the TTS Effector Ipgd Inhibits T Cell Migration
Cross-talk between Shigella and cells of the adaptive immunity: The TTS effector IpgD inhibits T cell migration Dissertation zur Erlangung des naturwissenschaftlichen Doktorgrades der Julius-Maximilians-Universität Würzburg vorgelegt von Christoph Konradt aus Schäßburg Würzburg, 2010 Eingereicht am: ........................................................................... Mitglieder der Promotionskommission: Vorsitzender: ............................................................................... 1. Gutachter: Prof. Dr. Dr. h.c. mult. Jörg Hacker 2. Gutachter: Prof. Dr. Ulrich Dobrindt Tag des Promotionskolloquiums: ................................................... Doktorurkunde ausgehändigt am: .................................................. Erklärung Die vorliegende Arbeit wurde von mir selbständig und nur unter Verwendung der angegebenen Quellen und Hilfsmittel angefertigt. Weiterhin erkläre ich, dass die Dissertation bisher nicht in gleicher oder ähnlicher Form in einem anderen Prüfungsverfahren vorgelegen hat, und ich bisher keine akademischen Grade erworben oder zu erwerben versucht habe. Würzburg, August 2010 Christoph Konradt Acknowledgements First of all I want to thank Prof. Dr. Dr. h. c. mult. Jörg Hacker for accepting the responsibility of supervising my PhD in the distance while the experiments where carried out in France and I also want to thank him for his support through all this time. I want to thank Prof. Dr. Ulrich Dobrindt for his kindness of being my second examiner. A special thanks goes to Prof. Philippe Sansonetti for giving me the opportunity of joining the Unité de Pathogénie Microbienne Moléculaire at the Institut Pasteur, for offering me an exciting PhD topic and for his scientific expertise and support during my thesis. I especially want to thank my supervisor Dr. Armelle Phalipon for her strong guidance during this work. I am grateful for the excellent supervision I received. She was a great support in so many situations in and beside the lab. -
Modulation of Lymphocyte Receptor Mobility by Locally Bound
Proc. Nat. Acad. Sci. USA Vol. 72, No. 4, pp. 1579-1583, April 1975 Modulation of Lymphocyte Receptor Mobility by Locally Bound Concanavalin A (cell membrane/cap formation/lectins/insolubilized concanavalin A) ICHIRO YAHARA AND GERALD M. EDELMAN The Rockefeller University, New York, N.Y. 10021 Contributed by Gerald M. Edelman, February 7, 1975 ABSTRACT Binding of concanavalin A (Con A) to the capping phenomenon raised the possibility that our earlier lymphocyte surface at room temperature leads to restric- observations on restriction of receptor mobility by Con A tion of the mobility of a variety of cell surface receptors in- immobilization of various cluding those for immunoglobulin (Ig), 0, H-2, j02-micro- might be explained by simple globulin, Fc receptors, as well as receptors for other receptors after their cross-linkage by multivalent Con A lectins. Addition of colchicine to the cell suspensions molecules to Con A receptors that are in turn anchored to reverses this effect and allows Con A receptors as well the hypothesized cytoplasmic assembly. as other receptors to form patches and caps. Cap- this we have prepared Con A ping of Con A receptors results in "co-capping" of Ig, In order to test possibility, H-2, 6, Fc receptors, and 62-microglobulin in the ab- bound to platelets and latex beads and have shown that local sence of ligands specific for these receptors. Receptors attachment of these particles to a small fraction of Con A binding Limulus hemagglutinin and wax bean agglutinin, receptor sites on the cell surface inhibits the mobility of Ig as well as those interacting with carbohydrate-specific and other receptors. -
In Migrating Cells, the Golgi Complex and the Position of the Centrosome Depend on Geometrical Constraints of the Substratum
2406 Research Article In migrating cells, the Golgi complex and the position of the centrosome depend on geometrical constraints of the substratum François Pouthas, Philippe Girard, Virginie Lecaudey, Thi Bach Nga Ly, Darren Gilmour, Christian Boulin, Rainer Pepperkok and Emmanuel G. Reynaud* Cell Biology and Cell Biophysics Programme, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany *Author for correspondence (e-mail: [email protected]) Accepted 9 April 2008 Journal of Cell Science 121, 2406-2414 Published by The Company of Biologists 2008 doi:10.1242/jcs.026849 Summary Although cells migrate in a constrained 3D environment in vivo, primordium as an in-vivo model of cells migrating in a in-vitro studies have mainly focused on the analysis of cells constrained environment and observe a similar localization of moving on 2D substrates. Under such conditions, the Golgi both the Golgi and the centrosome in the leading cells. We complex is always located towards the leading edge of the cell, propose that the positioning of the Golgi complex and the suggesting that it is involved in the directional movement. centrosome depends on the geometrical constraints applied to However, several lines of evidence indicate that this location the cell rather than on a precise migratory function in the can vary depending on the cell type, the environment or the leading region. developmental processes. We have used micro contact printing (μCP) to study the migration of cells that have a geometrically constrained shape within a polarized phenotype. Cells migrating Supplementary material available online at on micropatterned lines of fibronectin are polarized and migrate http://jcs.biologists.org/cgi/content/full/121/14/2406/DC1 in the same direction. -
The Prion Protein Inhibits Monocytic Cell Migration by Stimulating Β1 Integrin Adhesion and Uropod Formation Dion D
© 2015. Published by The Company of Biologists Ltd | Journal of Cell Science (2015) 128, 3018-3029 doi:10.1242/jcs.165365 RESEARCH ARTICLE The prion protein inhibits monocytic cell migration by stimulating β1 integrin adhesion and uropod formation Dion D. Richardson1,*, Simon Tol1,*, Eider Valle-Encinas1, Cayetano Pleguezuelos1, Ruben Bierings2, Dirk Geerts3 and Mar Fernandez-Borja1,‡ ABSTRACT PrP is highly expressed in the hematopoietic system, particularly The broad tissue distribution and evolutionary conservation of the in hematopoietic stem cells and in mature mononuclear leukocytes glycosylphosphatidylinositol (GPI)-anchored prion protein (PrP, also (Isaacs et al., 2006). Accordingly, PrP has been reported to have a in vivo known as PRNP) suggests that it plays a role in cellular homeostasis. role in several hematopoietic and immune cell functions , Given that integrin adhesion determines cell behavior, the proposed such as the self-renewal of long-term repopulating hematopoietic role of PrP in cell adhesion might underlie the various in vitro and stem cells (Kent et al., 2009; Zhang et al., 2006), macrophage in vivo effects associated with PrP loss-of-function, including the phagocytosis (de Almeida et al., 2005) and T cell activation immune phenotypes described in PrP−/− mice. Here, we investigated (Ballerini et al., 2006). However, the role of PrP in the innate the role of PrP in the adhesion and (transendothelial) migration of immune response has hardly been explored with the exception of −/− human (pro)monocytes. We found that PrP regulates β1-integrin- one study in which peritonitis was induced in PrP mice with −/− mediated adhesion of monocytes. Additionally, PrP controls the cell zymosan (de Almeida et al., 2005). -
Mir-34/449 Control Apical Actin Network Formation During Multiciliogenesis Through Small Gtpase Pathways
ARTICLE Received 7 Jul 2015 | Accepted 17 Aug 2015 | Published 18 Sep 2015 DOI: 10.1038/ncomms9386 OPEN miR-34/449 control apical actin network formation during multiciliogenesis through small GTPase pathways Benoıˆt Chevalier1,2,*, Anna Adamiok3,*, Olivier Mercey1,2,*, Diego R. Revinski3, Laure-Emmanuelle Zaragosi1,2, Andrea Pasini3, Laurent Kodjabachian3, Pascal Barbry1,2 & Brice Marcet1,2 Vertebrate multiciliated cells (MCCs) contribute to fluid propulsion in several biological processes. We previously showed that microRNAs of the miR-34/449 family trigger MCC differentiation by repressing cell cycle genes and the Notch pathway. Here, using human and Xenopus MCCs, we show that beyond this initial step, miR-34/449 later promote the assembly of an apical actin network, required for proper basal bodies anchoring. Identification of miR-34/449 targets related to small GTPase pathways led us to characterize R-Ras as a key regulator of this process. Protection of RRAS messenger RNA against miR-34/449 binding impairs actin cap formation and multiciliogenesis, despite a still active RhoA. We propose that miR-34/449 also promote relocalization of the actin binding protein Filamin-A, a known RRAS interactor, near basal bodies in MCCs. Our study illustrates the intricate role played by miR-34/449 in coordinating several steps of a complex differentiation programme by regulating distinct signalling pathways. 1 CNRS, Institut de Pharmacologie Mole´culaire et Cellulaire (IPMC), UMR-7275, 660 route des Lucioles, 06560 Sophia-Antipolis, France. 2 University of Nice-Sophia-Antipolis (UNS), Institut de Pharmacologie Mole´culaire et Cellulaire, 660 route des Lucioles, Valbonne, 06560 Sophia-Antipolis, France. -
Contractility of the Cell Rear Drives Invasion of Breast Tumor Cells in 3D Matrigel
Contractility of the cell rear drives invasion of breast tumor cells in 3D Matrigel Renaud Poinclouxa,b,1, Olivier Collina,c,2, Floria Lizárragaa,b, Maryse Romaoa,d, Marcel Debraye, Matthieu Piela,c, and Philippe Chavriera,b,3 aResearch Center, Institut Curie, F-75248 Paris, France; bMembrane and Cytoskeleton Dynamics, cSystems Cell Biology of Cell Polarity and Cell Division, and dStructure and Membrane Compartments, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, 75248 Paris Cedex 05, France; and eDépartement de Santé Publique et Biostatistique, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris-Descartes, 75006 Paris, France Edited by Joan S. Brugge, Harvard Medical School, Boston, MA, and approved December 21, 2010 (received for review August 18, 2010) Cancer cells use different modes of migration, including integrin- modes of motility in 3D and, hence, are thought to adapt to variable dependent mesenchymal migration of elongated cells along environmental clues (17, 18, 20, 23–25). elements of the 3D matrix as opposed to low-adhesion-, contraction- Several methods have been developed for visualizing and an- based amoeboid motility of rounded cells. We report that MDA- alyzing forces generated by cells during 2D migration. These MB-231 human breast adenocarcinoma cells invade 3D Matrigel studies revealed that propulsive forces that are produced by with a characteristic rounded morphology and with F-actin and myosin II on the F-actin network, which is linked to adhesion myosin-IIa accumulating at the cell rear in a uropod-like structure. sites underneath the protruding lamellipodium, support migra- MDA-MB-231 cells display neither lamellipodia nor bleb extensions tion (26, 27). -
Flotillin Microdomains Interact with the Cortical Cytoskeleton to Control Uropod Formation and Neutrophil Recruitment
JCB: Report Flotillin microdomains interact with the cortical cytoskeleton to control uropod formation and neutrophil recruitment Alexander Ludwig,1 Grant P. Otto,1 Kirsi Riento,1 Emily Hams,2 Padraic G. Fallon,2 and Ben J. Nichols1 1MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, England, UK 2Institute of Molecular Medicine, Trinity College Dublin, Dublin 2, Ireland e studied the function of plasma membrane flotillin microdomains, but the machinery required for microdomains defined by the proteins flotillin 1 sensing chemoattractant functions normally. Flotillin micro W and flotillin 2 in uropod formation and neu- domains specifically associate with myosin IIa, and spec- trophil chemotaxis. Flotillins become concentrated in the trins. Both uropod formation and myosin IIa activity are uropod of neutrophils after exposure to chemoattractants compromised in flotillin 1 knockout neutrophils. We con- such as N-formyl-Met-Leu-Phe (fMLP). Here, we show that clude that the association between flotillin microdomains mice lacking flotillin 1 do not have flotillin microdomains, and cortical cytoskeleton has important functions during and that recruitment of neutrophils toward fMLP in vivo is neutrophil migration, in uropod formation, and in the reduced in these mice. Ex vivo, migration of neutrophils regulation of myosin IIa. through a resistive matrix is reduced in the absence of Introduction Microdomains defined by the proteins flotillin 1 and flotillin 2 with the chemotactic bacterial peptide N-formyl-methionyl-leucyl- (also termed reggie 2 and reggie 1, respectively) are an appar- phenylalanine (fMLP; Rajendran et al., 2009; Rossy et al., ently ubiquitous feature of mammalian cells (Babuke and 2009). The uropod is a plasma membrane protrusion found at Tikkanen, 2007).