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More KJ, Kaur H, Simpson AGB, Spiegel FW, Dacks JB. Contractile vacuoles: a rapidly expanding (and occasionally diminishing?) understanding. Eur J Protistol 2024; 94:126078. [PMID: 38688044 DOI: 10.1016/j.ejop.2024.126078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 03/18/2024] [Accepted: 03/20/2024] [Indexed: 05/02/2024]
Abstract
Osmoregulation is the homeostatic mechanism essential for the survival of organisms in hypoosmotic and hyperosmotic conditions. In freshwater or soil dwelling protists this is frequently achieved through the action of an osmoregulatory organelle, the contractile vacuole. This endomembrane organelle responds to the osmotic challenges and compensates by collecting and expelling the excess water to maintain the cellular osmolarity. As compared with other endomembrane organelles, this organelle is underappreciated and under-studied. Here we review the reported presence or absence of contractile vacuoles across eukaryotic diversity, as well as the observed variability in the structure, function, and molecular machinery of this organelle. Our findings highlight the challenges and opportunities for constructing cellular and evolutionary models for this intriguing organelle.
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Affiliation(s)
- Kiran J More
- Division of Infectious Diseases, Department of Medicine, and Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada
| | - Harpreet Kaur
- Division of Infectious Diseases, Department of Medicine, and Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada
| | - Alastair G B Simpson
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, NS, Canada; Department of Biology, Dalhousie University, Halifax, NS, Canada
| | - Frederick W Spiegel
- Department of Biological Sciences, University of Arkansas, Fayetteville, AR, 72701, USA
| | - Joel B Dacks
- Division of Infectious Diseases, Department of Medicine, and Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada; Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic; Centre for Life's Origins and Evolution, Department of Genetics, Evolution, & Environment, University College, London, United Kingdom.
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2
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Cheng CY, Hernández J, Turkewitz AP. VPS8D, a CORVET subunit, is required to maintain the contractile vacuole complex in Tetrahymena thermophila. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.07.566071. [PMID: 37986963 PMCID: PMC10659352 DOI: 10.1101/2023.11.07.566071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Contractile vacuole complexes (CVCs) are complex osmoregulatory organelles, with vesicular (bladder) and tubular (spongiome) subcompartments. The mechanisms that underlie their formation and maintenance within the eukaryotic endomembrane network are poorly understood. In the Ciliate Tetrahymena thermophila, six differentiated CORVETs (class C core vacuole/endosome tethering complexes), with Vps8 subunits designated A-F, are likely to direct endosomal trafficking. Vps8Dp localizes to both bladder and spongiome. We show by inducible knockdown that VPS8D is essential to CVC organization and function. VPS8D knockdown increased susceptibility to osmotic shock, tolerated in the wildtype but triggering irreversible lethal swelling in the mutant. The knockdown rapidly triggered contraction of the spongiome and lengthened the period of the bladder contractile cycle. More prolonged knockdown resulted in disassembly of both the spongiome and bladder, and dispersal of proteins associated with those compartments. In stressed cells where the normally singular bladder is replaced by numerous vesicles bearing bladder markers, Vps8Dp concentrated conspicuously at long-lived inter-vesicle contact sites, consistent with tethering activity. Similarly, Vps8Dp in cell-free preparations accumulated at junctions formed after vacuoles came into close contact. Also consistent with roles for Vps8Dp in tethering and/or fusion were the emergence in knockdown cells of multiple vacuole-related structures, replacing the single bladder.
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Affiliation(s)
- Chao-Yin Cheng
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL, USA
| | - Josefina Hernández
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL, USA
| | - Aaron P. Turkewitz
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL, USA
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3
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Jimenez V, Miranda K, Ingrid A. The old and the new about the contractile vacuole of Trypanosoma cruzi. J Eukaryot Microbiol 2022; 69:e12939. [PMID: 35916682 PMCID: PMC11178379 DOI: 10.1111/jeu.12939] [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: 06/27/2022] [Revised: 07/27/2022] [Accepted: 07/27/2022] [Indexed: 11/28/2022]
Abstract
Osmoregulation is a conserved cellular process required for the survival of all organisms. In protists, the need for robust compensatory mechanisms that can maintain cell volume and tonicity within physiological range is even more relevant, as their life cycles are often completed in different environments. Trypanosoma cruzi, the protozoan pathogen responsible for Chagas disease, is transmitted by an insect vector to multiple types of mammalian hosts. The contractile vacuole complex (CVC) is an organelle that senses and compensates osmotic changes in the parasites, ensuring their survival upon ionic and osmotic challenges. Recent work shows that the contractile vacuole is also a key component of the secretory and endocytic pathways, regulating the selective targeting of surface proteins during differentiation. Here we summarize our current knowledge of the mechanisms involved in the osmoregulatory processes that take place in the vacuole, and we explore the new and exciting functions of this organelle in cell trafficking and signaling.
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Affiliation(s)
- Veronica Jimenez
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, California, USA
| | - Kildare Miranda
- Laboratorio de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Centro Nacional de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Augusto Ingrid
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, California, USA
- Laboratorio de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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4
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Plattner H. Ciliate Research. From Myth to Trendsetting Science. J Eukaryot Microbiol 2022; 69:e12926. [PMID: 35608570 DOI: 10.1111/jeu.12926] [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: 02/21/2022] [Revised: 05/18/2022] [Accepted: 05/18/2022] [Indexed: 11/28/2022]
Abstract
This special issue of the Journal of Eukaryotic Microbiology (JEM) summarizes achievements obtained by generations of researchers with ciliates in widely different disciplines. In fact, ciliates range among the first cells seen under the microscope centuries ago. Their beauty made them an object of scientia amabilis and their manifold reactions made them attractive for college experiments and finally challenged causal analyses at the cellular level. Some of this work was honored by a Nobel Prize. Some observations yielded a baseline for additional novel discoveries, occasionally facilitated by specific properties of some ciliates. This also offers some advantage in the exploration of closely related parasites (malaria). Articles contributed here by colleagues from all over the world encompass a broad spectrum of ciliate life, from genetics to evolution, from molecular cell biology to ecology, from intercellular signaling to epigenetics etc. This introductory chapter, largely based on my personal perception, aims at integrating work presented in this special issue of JEM into a broader historical context up to current research.
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Plattner H. Membrane Traffic and Ca 2+ -Signals in Ciliates. J Eukaryot Microbiol 2022; 69:e12895. [PMID: 35156735 DOI: 10.1111/jeu.12895] [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: 12/03/2021] [Revised: 02/01/2022] [Accepted: 02/01/2022] [Indexed: 11/30/2022]
Abstract
A Paramecium cell has as many types of membrane interactions as mammalian cells, as established with monoclonal antibodies by R. Allen and A. Fok. Since then, we have identified key-players, such as SNARE-proteins, Ca2+ -regulating proteins, including Ca2+ -channels, Ca2+ -pumps, Ca2+ -binding proteins of different affinity etc. at the molecular level, probed their function and localized them at the light and electron microscopy level. SNARE-proteins, in conjunction with a synaptotagmin-like Ca2+ -sensor protein, mediate membrane fusion. This interaction is additionally regulated by monomeric GTPases whose spectrum in Tetrahymena and Paramecium has been established by A. Turkewitz. As known from mammalian cells, GTPases are activated on membranes in conjunction with lumenal acidification by an H+ -ATPase. For these complex molecules we found in Paramecium an unsurpassed number of 17 a-subunit paralogs which connect the polymeric head and basis part, V1 and V0. (This multitude may reflect different local functional requirements.) Together with plasmalemmal Ca2+ -influx-channels, locally enriched intracellular InsP3 -type (InsP3 R, mainly in osmoregulatory system) and ryanodine receptor-like Ca2+ -release channels (ryanodine receptor-like proteins, RyR-LP), this complexity mediates Ca2+ signals for most flexible local membrane-to-membrane interactions. As we found, the latter channel types miss a substantial portion of the N-terminal part. Caffeine and 4-chloro-meta-cresol (the agent used to probe mutations of RyRs in man during surgery in malignant insomnia patients) initiate trichocyst exocytosis by activating Ca2+ -release channels type CRC-IV in the peripheral part of alveolar sacs. This is superimposed by Ca2+ -influx, i.e. a mechanism called "store-operated Ca2+ -entry" (SOCE). For the majority of key players, we have mapped paralogs throughout the Paramecium cell, with features in common or at variance in the different organelles participating in vesicle trafficking. Local values of free Ca2+ -concentration, [Ca2+ ]i , and their change, e.g. upon exocytosis stimulation, have been registered by flurochromes and chelator effects. In parallel we have registered release of Ca2+ from alveolar sacs by quenched-flow analysis combined with cryofixation and x-ray microanalysis.
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Rosa N, Shabardina V, Ivanova H, Sebé-Pedrós A, Yule DI, Bultynck G. Tracing the evolutionary history of Ca 2+-signaling modulation by human Bcl-2: Insights from the Capsaspora owczarzaki IP 3 receptor ortholog. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2021; 1868:119121. [PMID: 34400171 DOI: 10.1016/j.bbamcr.2021.119121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 07/14/2021] [Accepted: 08/11/2021] [Indexed: 01/08/2023]
Abstract
Recently, a functional IP3R ortholog (CO.IP3R-A) capable of IP3-induced Ca2+ release has been discovered in Capsaspora owczarzaki, a close unicellular relative to Metazoa. In contrast to mammalian IP3Rs, CO.IP3R-A is not modulated by Ca2+, ATP or PKA. Protein-sequence analysis revealed that CO.IP3R-A contained a putative binding site for anti-apoptotic Bcl-2, although Bcl-2 was not detected in Capsaspora owczarzaki and only appeared in Metazoa. Here, we examined whether human Bcl-2 could form a complex with CO.IP3R-A channels and modulate their Ca2+-flux properties using ectopic expression approaches in a HEK293 cell model in which all three IP3R isoforms were knocked out. We demonstrate that human Bcl-2 via its BH4 domain could functionally interact with CO.IP3R-A, thereby suppressing Ca2+ flux through CO.IP3R-A channels. The BH4 domain of Bcl-2 was sufficient for interaction with CO.IP3R-A channels. Moreover, mutating the Lys17 of Bcl-2's BH4 domain, the residue critical for Bcl-2-dependent modulation of mammalian IP3Rs, abrogated Bcl-2's ability to bind and inhibit CO.IP3R-A channels. Hence, this raises the possibility that a unicellular ancestor of animals already had an IP3R that harbored a Bcl-2-binding site. Bcl-2 proteins may have evolved as controllers of IP3R function by exploiting this pre-existing site, thereby counteracting Ca2+-dependent apoptosis.
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Affiliation(s)
- Nicolas Rosa
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, and Leuven Kanker Instituut, 3000 Leuven, Belgium
| | - Victoria Shabardina
- Institute of Evolutionary Biology, CSIC-Universitat Pompeu Fabra, 08003 Barcelona, Spain
| | - Hristina Ivanova
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, and Leuven Kanker Instituut, 3000 Leuven, Belgium
| | - Arnau Sebé-Pedrós
- Institute of Evolutionary Biology, CSIC-Universitat Pompeu Fabra, 08003 Barcelona, Spain; Centre for Genomic Regulation, Barcelona Institute of Science and Technology, 08003 Barcelona, Spain
| | - David I Yule
- Department of Pharmacology and Physiology, School of Medicine and Dentistry, University of Rochester, Rochester, NY 14642, USA
| | - Geert Bultynck
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, and Leuven Kanker Instituut, 3000 Leuven, Belgium.
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Dave N, Cetiner U, Arroyo D, Fonbuena J, Tiwari M, Barrera P, Lander N, Anishkin A, Sukharev S, Jimenez V. A novel mechanosensitive channel controls osmoregulation, differentiation, and infectivity in Trypanosoma cruzi. eLife 2021; 10:67449. [PMID: 34212856 PMCID: PMC8282336 DOI: 10.7554/elife.67449] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 07/01/2021] [Indexed: 12/19/2022] Open
Abstract
The causative agent of Chagas disease undergoes drastic morphological and biochemical modifications as it passes between hosts and transitions from extracellular to intracellular stages. The osmotic and mechanical aspects of these cellular transformations are not understood. Here we identify and characterize a novel mechanosensitive channel in Trypanosoma cruzi (TcMscS) belonging to the superfamily of small-conductance mechanosensitive channels (MscS). TcMscS is activated by membrane tension and forms a large pore permeable to anions, cations, and small osmolytes. The channel changes its location from the contractile vacuole complex in epimastigotes to the plasma membrane as the parasites develop into intracellular amastigotes. TcMscS knockout parasites show significant fitness defects, including increased cell volume, calcium dysregulation, impaired differentiation, and a dramatic decrease in infectivity. Our work provides mechanistic insights into components supporting pathogen adaptation inside the host, thus opening the exploration of mechanosensation as a prerequisite for protozoan infectivity.
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Affiliation(s)
- Noopur Dave
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, United States
| | - Ugur Cetiner
- Department of Biology, University of Maryland, College Park, United States
| | - Daniel Arroyo
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, United States
| | - Joshua Fonbuena
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, United States
| | - Megna Tiwari
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, United States
| | - Patricia Barrera
- Departmento de Biología, Facultad de Ciencias Exactas y Naturales, Instituto de Histologia y Embriologia IHEM-CONICET, Facultad de Medicina, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Noelia Lander
- Department of Biological Sciences, University of Cincinnati, Cincinnati, United States
| | - Andriy Anishkin
- Department of Biology, University of Maryland, College Park, United States
| | - Sergei Sukharev
- Department of Biology, University of Maryland, College Park, United States
| | - Veronica Jimenez
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, United States
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Pérez-Gordones MC, Ramírez-Iglesias JR, Benaim G, Mendoza M. A store-operated Ca 2+-entry in Trypanosoma equiperdum: Physiological evidences of its presence. Mol Biochem Parasitol 2021; 244:111394. [PMID: 34216677 DOI: 10.1016/j.molbiopara.2021.111394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 06/26/2021] [Accepted: 06/28/2021] [Indexed: 02/06/2023]
Abstract
The Trypanosomatidae family encompasses many unicellular organisms responsible of several tropical diseases that affect humans and animals. Livestock tripanosomosis caused by Trypanosoma brucei brucei (T. brucei), Trypanosoma equiperdum (T. equiperdum) and Trypanosoma evansi (T. evansi), have a significant socio-economic impact and limit animal protein productivity throughout the intertropical zones of the world. Similarly, to all organisms, the maintenance of Ca2+ homeostasis is vital for these parasites, and the mechanism involved in the intracellular Ca2+ regulation have been widely described. However, the evidences related to the mechanisms responsible for the Ca2+ entry are scarce. Even more, to date the presence of a store-operated Ca2+ channel (SOC) has not been reported. Despite the apparent absence of Orai and STIM-like proteins in these parasites, in the present work we demonstrate the presence of a store-operated Ca2+-entry (SOCE) in T. equiperdum, using physiological techniques. This Ca2+-entry is induced by thapsigargin (TG) and 2,5-di-t-butyl-1,4-benzohydroquinone (BHQ), and inhibited by 2-aminoethoxydiphenyl borate (2APB). Additionally, the use of bioinformatics techniques allowed us to identify putative transient receptor potential (TRP) channels, present in members of the Trypanozoon family, which would be possible candidates responsible for the SOCE described in the present work in T. equiperdum.
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Affiliation(s)
- María C Pérez-Gordones
- Instituto de Biología Experimental (IBE), Universidad Central de Venezuela (UCV), Caracas, Venezuela
| | - José R Ramírez-Iglesias
- Group of Neglected and Emerging Diseases, Epidemiology and Biodiversity, Health Sciences Faculty, Universidad Internacional SEK (UISEK), Quito, Ecuador
| | - Gustavo Benaim
- Instituto de Biología Experimental (IBE), Universidad Central de Venezuela (UCV), Caracas, Venezuela; Instituto de Estudios Avanzados (IDEA), Caracas, Venezuela
| | - Marta Mendoza
- Centro de Estudios Biomédicos y Veterinarios, Instituto de Estudios Científicos y Tecnológicos (IDECYT), Universidad Nacional Experimental Simón Rodríguez, Caracas, Venezuela.
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Cestari I. Phosphoinositide signaling and regulation in Trypanosoma brucei: Specialized functions in a protozoan pathogen. PLoS Pathog 2020; 16:e1008167. [PMID: 31895930 PMCID: PMC6939900 DOI: 10.1371/journal.ppat.1008167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Affiliation(s)
- Igor Cestari
- Institute of Parasitology, McGill University, Ste-Anne-de-Bellevue, Québec, Canada
- * E-mail:
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10
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Abstract
In the body, extracellular stimuli produce inositol 1,4,5-trisphosphate (IP3), an intracellular chemical signal that binds to the IP3 receptor (IP3R) to release calcium ions (Ca2+) from the endoplasmic reticulum. In the past 40 years, the wide-ranging functions mediated by IP3R and its genetic defects causing a variety of disorders have been unveiled. Recent cryo-electron microscopy and X-ray crystallography have resolved IP3R structures and begun to integrate with concurrent functional studies, which can explicate IP3-dependent opening of Ca2+-conducting gates placed ∼90 Å away from IP3-binding sites and its regulation by Ca2+. This review highlights recent research progress on the IP3R structure and function. We also propose how protein plasticity within IP3R, which involves allosteric gating and assembly transformations accompanied by rapid and chronic structural changes, would enable it to regulate diverse functions at cellular microdomains in pathophysiological states.
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Affiliation(s)
- Kozo Hamada
- Laboratory of Cell Calcium Signaling, Shanghai Institute for Advanced Immunochemical Studies (SIAIS), ShanghaiTech University, Shanghai, 201210, China; ,
| | - Katsuhiko Mikoshiba
- Laboratory of Cell Calcium Signaling, Shanghai Institute for Advanced Immunochemical Studies (SIAIS), ShanghaiTech University, Shanghai, 201210, China; ,
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Potapenko E, Negrão NW, Huang G, Docampo R. The acidocalcisome inositol-1,4,5-trisphosphate receptor of Trypanosoma brucei is stimulated by luminal polyphosphate hydrolysis products. J Biol Chem 2019; 294:10628-10637. [PMID: 31138655 DOI: 10.1074/jbc.ra119.007906] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 05/27/2019] [Indexed: 12/21/2022] Open
Abstract
Acidocalcisomes are acidic calcium stores rich in polyphosphate (polyP) and are present in trypanosomes and also in a diverse range of other organisms. Ca2+ is released from these organelles through a channel, inositol 1,4,5-trisphosphate receptor (TbIP3R), which is essential for growth and infectivity of the parasite Trypanosoma brucei However, the mechanism by which TbIP3R controls Ca2+ release is unclear. In this work, we expressed TbIP3R in a chicken B lymphocyte cell line in which the genes for all three vertebrate IP3Rs were stably ablated (DT40-3KO). We show that IP3-mediated Ca2+ release depends on Ca2+ but not on ATP concentration and is inhibited by heparin, caffeine, and 2-aminomethoxydiphenyl borate (2-APB). Excised patch clamp recordings from nuclear membranes of DT40 cells expressing only TbIP3R disclosed that luminal inorganic orthophosphate (Pi) or pyrophosphate (PPi), and neutral or alkaline pH can stimulate IP3-generated currents. In contrast, polyP or acidic pH did not induce these currents, and nuclear membranes obtained from cells expressing rat IP3R were unresponsive to polyP or its hydrolysis products. Our results are consistent with the notion that polyP hydrolysis products within acidocalcisomes or alkalinization of their luminal pH activate TbIP3R and Ca2+ release. We conclude that TbIP3R is well-adapted to its role as the major Ca2+ release channel of acidocalcisomes in T. brucei.
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Affiliation(s)
| | - Núria W Negrão
- From the Center for Tropical and Emerging Global Diseases and.,Department of Cellular Biology, University of Georgia, Athens, Georgia 30602
| | - Guozhong Huang
- From the Center for Tropical and Emerging Global Diseases and
| | - Roberto Docampo
- From the Center for Tropical and Emerging Global Diseases and .,Department of Cellular Biology, University of Georgia, Athens, Georgia 30602
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12
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The remembrance of the things past: Conserved signalling pathways link protozoa to mammalian nervous system. Cell Calcium 2018; 73:25-39. [DOI: 10.1016/j.ceca.2018.04.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 04/01/2018] [Accepted: 04/01/2018] [Indexed: 12/13/2022]
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13
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Plattner H. Evolutionary Cell Biology of Proteins from Protists to Humans and Plants. J Eukaryot Microbiol 2017; 65:255-289. [PMID: 28719054 DOI: 10.1111/jeu.12449] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 07/04/2017] [Accepted: 07/07/2017] [Indexed: 01/10/2023]
Abstract
During evolution, the cell as a fine-tuned machine had to undergo permanent adjustments to match changes in its environment, while "closed for repair work" was not possible. Evolution from protists (protozoa and unicellular algae) to multicellular organisms may have occurred in basically two lineages, Unikonta and Bikonta, culminating in mammals and angiosperms (flowering plants), respectively. Unicellular models for unikont evolution are myxamoebae (Dictyostelium) and increasingly also choanoflagellates, whereas for bikonts, ciliates are preferred models. Information accumulating from combined molecular database search and experimental verification allows new insights into evolutionary diversification and maintenance of genes/proteins from protozoa on, eventually with orthologs in bacteria. However, proteins have rarely been followed up systematically for maintenance or change of function or intracellular localization, acquirement of new domains, partial deletion (e.g. of subunits), and refunctionalization, etc. These aspects are discussed in this review, envisaging "evolutionary cell biology." Protozoan heritage is found for most important cellular structures and functions up to humans and flowering plants. Examples discussed include refunctionalization of voltage-dependent Ca2+ channels in cilia and replacement by other types during evolution. Altogether components serving Ca2+ signaling are very flexible throughout evolution, calmodulin being a most conservative example, in contrast to calcineurin whose catalytic subunit is lost in plants, whereas both subunits are maintained up to mammals for complex functions (immune defense and learning). Domain structure of R-type SNAREs differs in mono- and bikonta, as do Ca2+ -dependent protein kinases. Unprecedented selective expansion of the subunit a which connects multimeric base piece and head parts (V0, V1) of H+ -ATPase/pump may well reflect the intriguing vesicle trafficking system in ciliates, specifically in Paramecium. One of the most flexible proteins is centrin when its intracellular localization and function throughout evolution is traced. There are many more examples documenting evolutionary flexibility of translation products depending on requirements and potential for implantation within the actual cellular context at different levels of evolution. From estimates of gene and protein numbers per organism, it appears that much of the basic inventory of protozoan precursors could be transmitted to highest eukaryotic levels, with some losses and also with important additional "inventions."
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Affiliation(s)
- Helmut Plattner
- Department of Biology, University of Konstanz, P. O. Box M625, Konstanz, 78457, Germany
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14
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Garcia CRS, Alves E, Pereira PHS, Bartlett PJ, Thomas AP, Mikoshiba K, Plattner H, Sibley LD. InsP3 Signaling in Apicomplexan Parasites. Curr Top Med Chem 2017; 17:2158-2165. [PMID: 28137231 PMCID: PMC5490149 DOI: 10.2174/1568026617666170130121042] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 10/20/2016] [Accepted: 10/30/2016] [Indexed: 11/22/2022]
Abstract
Background:
Phosphoinositides (PIs) and their derivatives are essential cellular components that form the building blocks for cell membranes and regulate numerous cell functions. Specifically, the ability to generate myo-inositol 1,4,5-trisphosphate (InsP3) via phospholipase C (PLC) dependent hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2) to InsP3 and diacylglycerol (DAG) initiates intracellular calcium signaling events representing a fundamental signaling mechanism dependent on PIs. InsP3 produced by PI turnover as a second messenger causes intracellular calcium release, especially from endoplasmic reticulum, by binding to the InsP3 receptor (InsP3R). Various PIs and the enzymes, such as phosphatidylinositol synthase and phosphatidylinositol 4-kinase, necessary for their turnover have been characterized in Apicomplexa, a large phylum of mostly commensal organisms that also includes several clinically relevant parasites. However, InsP3Rs have not been identified in genomes of apicomplexans, despite evidence that these parasites produce InsP3 that mediates intracellular Ca2+ signaling. Conclusion: Evidence to supporting IP3-dependent signaling cascades in apicomplexans suggests that they may harbor a primitive or non-canonical InsP3R. Understanding these pathways may be informative about early branching eukaryotes, where such signaling pathways also diverge from animal systems, thus identifying potential novel and essential targets for therapeutic intervention.
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Affiliation(s)
- Celia R S Garcia
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo. Sao Paulo 05508-090, Brazil
| | - Eduardo Alves
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo. Sao Paulo 05508-000, Brazil
| | - Pedro H S Pereira
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo. Sao Paulo 05508-090, Brazil,Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo. Sao Paulo 05508-000, Brazil
| | - Paula J Bartlett
- New Jersey Medical School, Rutgers, The State University of New Jersey, New Jersey, USA
| | - Andrew P Thomas
- New Jersey Medical School, Rutgers, The State University of New Jersey, New Jersey, USA
| | - Katsuhiko Mikoshiba
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, Wako, Saitama, Japan
| | - Helmut Plattner
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | - L David Sibley
- Department of Molecular Microbiology, Washington University Sch. Med., Saint Louis, USA
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15
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Bickerton P, Sello S, Brownlee C, Pittman JK, Wheeler GL. Spatial and temporal specificity of Ca 2+ signalling in Chlamydomonas reinhardtii in response to osmotic stress. THE NEW PHYTOLOGIST 2016; 212:920-933. [PMID: 27516045 PMCID: PMC5111745 DOI: 10.1111/nph.14128] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 06/25/2016] [Indexed: 05/06/2023]
Abstract
Ca2+ -dependent signalling processes enable plants to perceive and respond to diverse environmental stressors, such as osmotic stress. A clear understanding of the role of spatiotemporal Ca2+ signalling in green algal lineages is necessary in order to understand how the Ca2+ signalling machinery has evolved in land plants. We used single-cell imaging of Ca2+ -responsive fluorescent dyes in the unicellular green alga Chlamydomonas reinhardtii to examine the specificity of spatial and temporal dynamics of Ca2+ elevations in the cytosol and flagella in response to salinity and osmotic stress. We found that salt stress induced a single Ca2+ elevation that was modulated by the strength of the stimulus and originated in the apex of the cell, spreading as a fast Ca2+ wave. By contrast, hypo-osmotic stress induced a series of repetitive Ca2+ elevations in the cytosol that were spatially uniform. Hypo-osmotic stimuli also induced Ca2+ elevations in the flagella that occurred independently from those in the cytosol. Our results indicate that the requirement for Ca2+ signalling in response to osmotic stress is conserved between land plants and green algae, but the distinct spatial and temporal dynamics of osmotic Ca2+ elevations in C. reinhardtii suggest important mechanistic differences between the two lineages.
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Affiliation(s)
- Peter Bickerton
- Marine Biological AssociationCitadel HillPlymouthPL1 2PBUK
- Faculty of Life SciencesUniversity of ManchesterOxford RoadManchesterM13 9PTUK
| | - Simone Sello
- Marine Biological AssociationCitadel HillPlymouthPL1 2PBUK
- Department of BiologyUniversity of PadovaVia U. Bassi 58/B35131PadovaItaly
| | - Colin Brownlee
- Marine Biological AssociationCitadel HillPlymouthPL1 2PBUK
- School of Ocean and Earth ScienceUniversity of SouthamptonSouthamptonSO14 3ZHUK
| | - Jon K. Pittman
- Faculty of Life SciencesUniversity of ManchesterOxford RoadManchesterM13 9PTUK
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16
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Lander N, Chiurillo MA, Storey M, Vercesi AE, Docampo R. CRISPR/Cas9-mediated endogenous C-terminal Tagging of Trypanosoma cruzi Genes Reveals the Acidocalcisome Localization of the Inositol 1,4,5-Trisphosphate Receptor. J Biol Chem 2016; 291:25505-25515. [PMID: 27793988 DOI: 10.1074/jbc.m116.749655] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 09/29/2016] [Indexed: 11/06/2022] Open
Abstract
Methods for genetic manipulation of Trypanosoma cruzi, the etiologic agent of Chagas disease, have been highly inefficient, and no endogenous tagging of genes has been reported to date. We report here the use of the CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 (CRISPR-associated gene 9) system for endogenously tagging genes in this parasite. The utility of the method was established by tagging genes encoding proteins of known localization such as TcFCaBP (flagellar calcium binding protein) and TcVP1 (vacuolar proton pyrophosphatase), and two proteins of undefined or disputed localization, the TcMCU (mitochondrial calcium uniporter) and TcIP3R (inositol 1,4,5-trisphosphate receptor). We confirmed the flagellar and acidocalcisome localization of TcFCaBP and TcVP1 by co-localization with antibodies to the flagellum and acidocalcisomes, respectively. As expected, TcMCU was co-localized with the voltage-dependent anion channel to the mitochondria. However, in contrast to previous reports and our own results using overexpressed TcIP3R, endogenously tagged TcIP3R showed co-localization with antibodies against VP1 to acidocalcisomes. These results are also in agreement with our previous reports on the localization of this channel to acidocalcisomes of Trypanosoma brucei and suggest that caution should be exercised when overexpression of tagged genes is done to localize proteins in T. cruzi.
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Affiliation(s)
- Noelia Lander
- From the Departamento de Patologia Clínica, Faculdade de Ciências Médicas, Universidade Estadual de Campinas, Campinas, São Paulo 13083, Brazil and
| | - Miguel A Chiurillo
- From the Departamento de Patologia Clínica, Faculdade de Ciências Médicas, Universidade Estadual de Campinas, Campinas, São Paulo 13083, Brazil and
| | - Melissa Storey
- the Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia 30602
| | - Anibal E Vercesi
- From the Departamento de Patologia Clínica, Faculdade de Ciências Médicas, Universidade Estadual de Campinas, Campinas, São Paulo 13083, Brazil and
| | - Roberto Docampo
- From the Departamento de Patologia Clínica, Faculdade de Ciências Médicas, Universidade Estadual de Campinas, Campinas, São Paulo 13083, Brazil and .,the Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia 30602
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17
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Staudt E, Ramasamy P, Plattner H, Simon M. Differential subcellular distribution of four phospholipase C isoforms and secretion of GPI-PLC activity. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:3157-3168. [PMID: 27693913 DOI: 10.1016/j.bbamem.2016.09.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 09/04/2016] [Accepted: 09/27/2016] [Indexed: 12/11/2022]
Abstract
Phospholipase C (PLC) is an important enzyme of signal transduction pathways by generation of second messengers from membrane lipids. PLCs are also indicated to cleave glycosylphosphatidylinositol (GPI)-anchors of surface proteins thus releasing these into the environment. However, it remains unknown whether this enzymatic activity on the surface is due to distinct PLC isoforms in higher eukaryotes. Ciliates have, in contrast to other unicellular eukaryotes, multiple PLC isoforms as mammals do. Thus, Paramecium represents a perfect model to study subcellular distribution and potential surface activity of PLC isoforms. We have identified distinct subcellular localizations of four PLC isoforms indicating functional specialization. The association with different calcium release channels (CRCs) argues for distinct subcellular functions. They may serve as PI-PLCs in microdomains for local second messenger responses rather than free floating IP3. In addition, all isoforms can be found on the cell surface and they are found together with GPI-cleaved surface proteins in salt/ethanol washes of cells. We can moreover show them in medium supernatants of living cells where they have access to GPI-anchored surface proteins. Among the isoforms we cannot assign GPI-PLC activity to specific PLC isoforms; rather each PLC is potentially responsible for the release of GPI-anchored proteins from the surface.
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Affiliation(s)
- Emanuel Staudt
- Saarland University, Molecular Cell Dynamics, Centre for Human and Molecular Biology, Campus A2 4, 66123 Saarbrücken, Germany; University of Kaiserslautern, Department of Biology, Erwin-Schrödinger Straße, Building Nr. 14, 67663 Kaiserslautern, Germany
| | - Pathmanaban Ramasamy
- Saarland University, Molecular Cell Dynamics, Centre for Human and Molecular Biology, Campus A2 4, 66123 Saarbrücken, Germany
| | - Helmut Plattner
- University of Konstanz, Senior Research Group for Cell Biology and Ultrastructure Research, Department of Biology, 78457 Konstanz, Germany
| | - Martin Simon
- Saarland University, Molecular Cell Dynamics, Centre for Human and Molecular Biology, Campus A2 4, 66123 Saarbrücken, Germany.
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18
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Plattner H. Signalling in ciliates: long- and short-range signals and molecular determinants for cellular dynamics. Biol Rev Camb Philos Soc 2015; 92:60-107. [PMID: 26487631 DOI: 10.1111/brv.12218] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 07/28/2015] [Accepted: 08/21/2015] [Indexed: 12/30/2022]
Abstract
In ciliates, unicellular representatives of the bikont branch of evolution, inter- and intracellular signalling pathways have been analysed mainly in Paramecium tetraurelia, Paramecium multimicronucleatum and Tetrahymena thermophila and in part also in Euplotes raikovi. Electrophysiology of ciliary activity in Paramecium spp. is a most successful example. Established signalling mechanisms include plasmalemmal ion channels, recently established intracellular Ca2+ -release channels, as well as signalling by cyclic nucleotides and Ca2+ . Ca2+ -binding proteins (calmodulin, centrin) and Ca2+ -activated enzymes (kinases, phosphatases) are involved. Many organelles are endowed with specific molecules cooperating in signalling for intracellular transport and targeted delivery. Among them are recently specified soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs), monomeric GTPases, H+ -ATPase/pump, actin, etc. Little specification is available for some key signal transducers including mechanosensitive Ca2+ -channels, exocyst complexes and Ca2+ -sensor proteins for vesicle-vesicle/membrane interactions. The existence of heterotrimeric G-proteins and of G-protein-coupled receptors is still under considerable debate. Serine/threonine kinases dominate by far over tyrosine kinases (some predicted by phosphoproteomic analyses). Besides short-range signalling, long-range signalling also exists, e.g. as firmly installed microtubular transport rails within epigenetically determined patterns, thus facilitating targeted vesicle delivery. By envisaging widely different phenomena of signalling and subcellular dynamics, it will be shown (i) that important pathways of signalling and cellular dynamics are established already in ciliates, (ii) that some mechanisms diverge from higher eukaryotes and (iii) that considerable uncertainties still exist about some essential aspects of signalling.
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Affiliation(s)
- Helmut Plattner
- Department of Biology, University of Konstanz, PO Box M625, 78457, Konstanz, Germany
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19
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Plattner H. Molecular aspects of calcium signalling at the crossroads of unikont and bikont eukaryote evolution – The ciliated protozoan Paramecium in focus. Cell Calcium 2015; 57:174-85. [DOI: 10.1016/j.ceca.2014.12.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 12/01/2014] [Accepted: 12/02/2014] [Indexed: 12/19/2022]
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20
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Plattner H, Verkhratsky A. The ancient roots of calcium signalling evolutionary tree. Cell Calcium 2015; 57:123-32. [DOI: 10.1016/j.ceca.2014.12.004] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 12/05/2014] [Indexed: 12/26/2022]
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21
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Evolution of acidic Ca2+ stores and their resident Ca2+-permeable channels. Cell Calcium 2015; 57:222-30. [DOI: 10.1016/j.ceca.2014.12.005] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 12/05/2014] [Accepted: 12/09/2014] [Indexed: 11/18/2022]
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22
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Kumar U, Saier MH. Comparative Genomic Analysis of Integral Membrane Transport Proteins in Ciliates. J Eukaryot Microbiol 2014; 62:167-87. [DOI: 10.1111/jeu.12156] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 04/23/2014] [Accepted: 04/28/2014] [Indexed: 11/25/2022]
Affiliation(s)
- Ujjwal Kumar
- Division of Biological Sciences; University of California at San Diego; La Jolla California
| | - Milton H. Saier
- Division of Biological Sciences; University of California at San Diego; La Jolla California
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23
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Cai X, Wang X, Patel S, Clapham DE. Insights into the early evolution of animal calcium signaling machinery: a unicellular point of view. Cell Calcium 2014; 57:166-73. [PMID: 25498309 PMCID: PMC4355082 DOI: 10.1016/j.ceca.2014.11.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 11/18/2014] [Accepted: 11/24/2014] [Indexed: 11/15/2022]
Abstract
The basic principles of Ca(2+) regulation emerged early in prokaryotes. Ca(2+) signaling acquired more extensive and varied functions when life evolved into multicellular eukaryotes with intracellular organelles. Animals, fungi and plants display differences in the mechanisms that control cytosolic Ca(2+) concentrations. The aim of this review is to examine recent findings from comparative genomics of Ca(2+) signaling molecules in close unicellular relatives of animals and in common unicellular ancestors of animals and fungi. Also discussed are the evolution and origins of the sperm-specific CatSper channel complex, cation/Ca(2+) exchangers and four-domain voltage-gated Ca(2+) channels. Newly identified evolutionary evidence suggests that the distinct Ca(2+) signaling machineries in animals, plants and fungi likely originated from an ancient Ca(2+) signaling machinery prior to early eukaryotic radiation.
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Affiliation(s)
- Xinjiang Cai
- Division of Endocrinology, Metabolism and Nutrition, Department of Medicine, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08903, USA.
| | - Xiangbing Wang
- Division of Endocrinology, Metabolism and Nutrition, Department of Medicine, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08903, USA
| | - Sandip Patel
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - David E Clapham
- Howard Hughes Medical Institute, Department of Cardiology, Boston Children's Hospital, Boston, MA 02115, USA; Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
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24
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Seo MD, Enomoto M, Ishiyama N, Stathopulos PB, Ikura M. Structural insights into endoplasmic reticulum stored calcium regulation by inositol 1,4,5-trisphosphate and ryanodine receptors. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:1980-91. [PMID: 25461839 DOI: 10.1016/j.bbamcr.2014.11.023] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Revised: 11/17/2014] [Accepted: 11/19/2014] [Indexed: 10/24/2022]
Abstract
The two major calcium (Ca²⁺) release channels on the sarco/endoplasmic reticulum (SR/ER) are inositol 1,4,5-trisphosphate and ryanodine receptors (IP3Rs and RyRs). They play versatile roles in essential cell signaling processes, and abnormalities of these channels are associated with a variety of diseases. Structural information on IP3Rs and RyRs determined using multiple techniques including X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy and cryo-electron microscopy (EM), has significantly advanced our understanding of the mechanisms by which these Ca²⁺ release channels function under normal and pathophysiological circumstances. In this review, structural advances on the understanding of the mechanisms of IP3R and RyR function and dysfunction are summarized. This article is part of a Special Issue entitled: 13th European Symposium on Calcium.
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Affiliation(s)
- Min-Duk Seo
- Department of Molecular Science and Technology, Ajou University, Suwon, Gyeonggi 443-749, Republic of Korea; College of Pharmacy, Ajou University, Suwon, Gyeonggi 443-749, Republic of Korea
| | - Masahiro Enomoto
- Princess Margaret Cancer Centre, University Health Network, University of Toronto, Toronto, ON M5G 1L7, Canada
| | - Noboru Ishiyama
- Princess Margaret Cancer Centre, University Health Network, University of Toronto, Toronto, ON M5G 1L7, Canada
| | - Peter B Stathopulos
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A 5C1, Canada
| | - Mitsuhiko Ikura
- Princess Margaret Cancer Centre, University Health Network, University of Toronto, Toronto, ON M5G 1L7, Canada.
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25
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Leondaritis G, Galanopoulou D. Emerging roles of phosphoinositide-specific phospholipases C in the ciliatesTetrahymenaandParamecium. Commun Integr Biol 2014. [DOI: 10.4161/cib.16295] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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26
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Plattner H. Calcium signalling in the ciliated protozoan model, Paramecium: strict signal localisation by epigenetically controlled positioning of different Ca²⁺-channels. Cell Calcium 2014; 57:203-13. [PMID: 25277862 DOI: 10.1016/j.ceca.2014.09.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 09/01/2014] [Indexed: 11/17/2022]
Abstract
The Paramecium tetraurelia cell is highly organised, with regularly spaced elements pertinent to Ca(2+) signalling under epigenetic control. Vesicles serving as stationary Ca(2+) stores or undergoing trafficking contain Ca(2+)-release channels (PtCRCs) which, according to sequence and domain comparison, are related either to inositol 1,4,5-trisphosphate (InsP3) receptors (IP3R) or to ryanodine receptor-like proteins (RyR-LP) or to both, with intermediate characteristics or deviation from conventional domain structure. Six groups of such PtCRCs have been found. The ryanodine-InsP3-receptor homology (RIH) domain is not always recognisable, in contrast to the channel domain with six trans-membrane domains and the pore between transmembrane domain 5 and 6. Two CRC subtypes tested more closely, PtCRC-II and PtCRC-IV, with and without an InsP3-binding domain, reacted to InsP3 and to caffeine, respectively, and hence represent IP3Rs and RyR-LPs. IP3Rs occur in the contractile vacuole complex where they allow for stochastic constitutive Ca(2+) reflux into the cytosol. RyR-LPs are localised to cortical Ca(2+) stores; they are engaged in dense core-secretory vesicle exocytosis by Ca(2+) release, superimposed by Ca(2+)-influx via non-ciliary Ca(2+)-channels. One or two different types of PtCRCs also occur in other vesicles undergoing trafficking. Since the PtCRCs described combine different features they are considered derivatives of primitive precursors. The highly regular, epigenetically controlled design of a Paramecium cell allows it to make Ca(2+) available very locally, in a most efficient way, along predetermined trafficking pathways, including regulation of exocytosis, endocytosis, phagocytosis and recycling phenomena. The activity of cilia is also regulated by Ca(2+), yet independently from any CRCs, by de- and hyperpolarisation of the cell membrane potential.
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Affiliation(s)
- Helmut Plattner
- Department of Biology, University of Konstanz, P.O. Box M625, 78457 Konstanz, Germany.
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27
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Nie Y, Huang F, Dong S, Li L, Gao P, Zhao H, Wang Y, Han S. Identification of inositol 1,4,5-trisphosphate-binding proteins by heparin-agarose affinity purification and LTQORBITRAPMS in Oryza sativa. Proteomics 2014; 14:2335-8. [DOI: 10.1002/pmic.201400042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 05/04/2014] [Accepted: 07/18/2014] [Indexed: 11/09/2022]
Affiliation(s)
- Yanli Nie
- Beijing Key Laboratory of Gene Resource and Molecular Development; Beijing Normal University, College of Life Sciences; Beijing P. R. China
| | - Feifei Huang
- Beijing Key Laboratory of Gene Resource and Molecular Development; Beijing Normal University, College of Life Sciences; Beijing P. R. China
| | - Shujun Dong
- Beijing Key Laboratory of Gene Resource and Molecular Development; Beijing Normal University, College of Life Sciences; Beijing P. R. China
| | - Lin Li
- National Institute of Biological Sciences; Beijing P. R. China
| | - Ping Gao
- Beijing Key Laboratory of Gene Resource and Molecular Development; Beijing Normal University, College of Life Sciences; Beijing P. R. China
| | - Heping Zhao
- Beijing Key Laboratory of Gene Resource and Molecular Development; Beijing Normal University, College of Life Sciences; Beijing P. R. China
| | - Yingdian Wang
- Beijing Key Laboratory of Gene Resource and Molecular Development; Beijing Normal University, College of Life Sciences; Beijing P. R. China
| | - Shengcheng Han
- Beijing Key Laboratory of Gene Resource and Molecular Development; Beijing Normal University, College of Life Sciences; Beijing P. R. China
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28
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Niyogi S, Mucci J, Campetella O, Docampo R. Rab11 regulates trafficking of trans-sialidase to the plasma membrane through the contractile vacuole complex of Trypanosoma cruzi. PLoS Pathog 2014; 10:e1004224. [PMID: 24968013 PMCID: PMC4072791 DOI: 10.1371/journal.ppat.1004224] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 05/19/2014] [Indexed: 01/09/2023] Open
Abstract
Trypanosoma cruzi is the etiologic agent of Chagas disease. Although this is not a free-living organism it has conserved a contractile vacuole complex (CVC) to regulate its osmolarity. This obligate intracellular pathogen is, in addition, dependent on surface proteins to invade its hosts. Here we used a combination of genetic and biochemical approaches to delineate the contribution of the CVC to the traffic of glycosylphosphatidylinositol (GPI)-anchored proteins to the plasma membrane of the parasite and promote host invasion. While T. cruzi Rab11 (GFP-TcRab11) localized to the CVC, a dominant negative (DN) mutant tagged with GFP (GFP-TcRab11DN) localized to the cytosol, and epimastigotes expressing this mutant were less responsive to hyposmotic and hyperosmotic stress. Mutant parasites were still able to differentiate into metacyclic forms and infect host cells. GPI-anchored trans-sialidase (TcTS), mucins of the 60-200 KDa family, and trypomastigote small surface antigen (TcTSSA II) co-localized with GFP-TcRab11 to the CVC during transformation of intracellular amastigotes into trypomastigotes. Mucins of the gp35/50 family also co-localized with the CVC during metacyclogenesis. Parasites expressing GFP-TcRab11DN prevented TcTS, but not other membrane proteins, from reaching the plasma membrane, and were less infective as compared to wild type cells. Incubation of these mutants in the presence of exogenous recombinant active, but not inactive, TcTS, and a sialic acid donor, before infecting host cells, partially rescued infectivity of trypomastigotes. Taking together these results reveal roles of TcRab11 in osmoregulation and trafficking of trans-sialidase to the plasma membrane, the role of trans-sialidase in promoting infection, and a novel unconventional mechanism of GPI-anchored protein secretion.
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Affiliation(s)
- Sayantanee Niyogi
- Department of Cellular Biology and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
| | - Juan Mucci
- Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín/Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Oscar Campetella
- Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín/Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Roberto Docampo
- Department of Cellular Biology and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
- * E-mail:
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29
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Abstract
Ca(2+)-signaling pathways and intracellular Ca(2+) channels are present in protozoa. Ancient origin of inositol 1,4,5-trisphosphate receptors (IP3Rs) and other intracellular channels predates the divergence of animals and fungi as evidenced by their presence in the choanoflagellate Monosiga brevicollis, the closest known relative to metazoans. The first protozoan IP3R cloned, from the ciliate Paramecium, displays strong sequence similarity to the rat type 3 IP3R. This ciliate has a large number of IP3- and ryanodine(Ry)-like receptors in six subfamilies suggesting the evolutionary adaptation to local requirements for an expanding diversification of vesicle trafficking. IP3Rs have also been functionally characterized in trypanosomatids, where they are essential for growth, differentiation, and establishment of infection. The presence of the mitochondrial calcium uniporter (MCU) in a number of protozoa indicates that mitochondrial regulation of Ca(2+) signaling is also an early appearance in evolution, and contributed to the discovery of the molecular nature of this channel in mammalian cells. There is only sequence evidence for the occurrence of two-pore channels (TPCs), transient receptor potential Ca(2+) channels (TRPCs) and intracellular mechanosensitive Ca(2+)-channels in Paramecium and in parasitic protozoa.
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30
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Genome-wide analysis of the phosphoinositide kinome from two ciliates reveals novel evolutionary links for phosphoinositide kinases in eukaryotic cells. PLoS One 2013; 8:e78848. [PMID: 24244373 PMCID: PMC3823935 DOI: 10.1371/journal.pone.0078848] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 09/16/2013] [Indexed: 11/19/2022] Open
Abstract
Background The complexity of phosphoinositide signaling in higher eukaryotes is partly due to expansion of specific families and types of phosphoinositide kinases (PIKs) that can generate all phosphoinositides via multiple routes. This is particularly evident in the PI3Ks and PIPKs, and it is considered an evolutionary trait associated with metazoan diversification. Yet, there are limited comprehensive studies on the PIK repertoire of free living unicellular organisms. Methodology/Principal Findings We undertook a genome-wide analysis of putative PIK genes in two free living ciliated cells, Tetrahymena and Paramecium. The Tetrahymena thermophila and Paramecium tetraurelia genomes were probed with representative kinases from all families and types. Putative homologs were verified by EST, microarray and deep RNA sequencing database searches and further characterized for domain structure, catalytic efficiency, expression patterns and phylogenetic relationships. In total, we identified and characterized 22 genes in the Tetrahymena thermophila genome and 62 highly homologues genes in Paramecium tetraurelia suggesting a tight evolutionary conservation in the ciliate lineage. Comparison to the kinome of fungi reveals a significant expansion of PIK genes in ciliates. Conclusions/Significance Our study highlights four important aspects concerning ciliate and other unicellular PIKs. First, ciliate-specific expansion of PI4KIII-like genes. Second, presence of class I PI3Ks which, at least in Tetrahymena, are associated with a metazoan-type machinery for PIP3 signaling. Third, expansion of divergent PIPK enzymes such as the recently described type IV transmembrane PIPKs. Fourth, presence of possible type II PIPKs and presumably inactive PIKs (hence, pseudo-PIKs) not previously described. Taken together, our results provide a solid framework for future investigation of the roles of PIKs in ciliates and indicate that novel functions and novel regulatory pathways of phosphoinositides may be more widespread than previously thought in unicellular organisms.
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31
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Stathopulos PB, Seo MD, Enomoto M, Amador FJ, Ishiyama N, Ikura M. Themes and variations in ER/SR calcium release channels: structure and function. Physiology (Bethesda) 2013; 27:331-42. [PMID: 23223627 DOI: 10.1152/physiol.00013.2012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Calcium (Ca(2+)) release from reticular stores is a vital regulatory signal in eukaryotes. Recent structural data on large NH(2)-terminal regions of IP(3)Rs and RyRs and their tetrameric arrangement in the full-length context reveal striking mechanistic similarities in Ca(2+) release channel function. A common ancestor found in unicellular genomes underscores the fundamentality of these elements to Ca(2+) release channels.
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Affiliation(s)
- Peter B Stathopulos
- Ontario Cancer Institute and Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
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Plattner H. Calcium regulation in the protozoan model, Paramecium tetraurelia. J Eukaryot Microbiol 2013; 61:95-114. [PMID: 24001309 DOI: 10.1111/jeu.12070] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 06/21/2013] [Accepted: 06/28/2013] [Indexed: 01/24/2023]
Abstract
Early in eukaryotic evolution, the cell has evolved a considerable inventory of proteins engaged in the regulation of intracellular Ca(2+) concentrations, not only to avoid toxic effects but beyond that to exploit the signaling capacity of Ca(2+) by small changes in local concentration. Among protozoa, the ciliate Paramecium may now be one of the best analyzed models. Ciliary activity and exo-/endocytosis are governed by Ca(2+) , the latter by Ca(2+) mobilization from alveolar sacs and a superimposed store-operated Ca(2+) -influx. Paramecium cells possess plasma membrane- and endoplasmic reticulum-resident Ca(2+) -ATPases/pumps (PMCA, SERCA), a variety of Ca(2+) influx channels, including mechanosensitive and voltage-dependent channels in the plasma membrane, furthermore a plethora of Ca(2+) -release channels (CRC) of the inositol 1,4,5-trisphosphate and ryanodine receptor type in different compartments, notably the contractile vacuole complex and the alveolar sacs, as well as in vesicles participating in vesicular trafficking. Additional types of CRC probably also occur but they have not been identified at a molecular level as yet, as is the equivalent of synaptotagmin as a Ca(2+) sensor for exocytosis. Among established targets and sensors of Ca(2+) in Paramecium are calmodulin, calcineurin, as well as Ca(2+) /calmodulin-dependent protein kinases, all with multiple functions. Thus, basic elements of Ca(2+) signaling are available for Paramecium.
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Affiliation(s)
- Helmut Plattner
- Department of Biology, University of Konstanz, P.O. Box 5544, 78457, Konstanz, Germany
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Plattner H. The contractile vacuole complex of protists--new cues to function and biogenesis. Crit Rev Microbiol 2013; 41:218-27. [PMID: 23919298 DOI: 10.3109/1040841x.2013.821650] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The contractile vacuole complex (CVC) of freshwater protists sequesters the excess of water and ions (Ca(2+)) for exocytosis cycles at the pore. Sequestration is based on a chemiosmotic proton gradient produced by a V-type H(+)-ATPase. So far, many pieces of information available have not been combined to a comprehensive view on CVC biogenesis and function. One main function now appears as follows. Ca(2+)-release channels, type inositol 1,4,5-trisphosphate receptors (InsP3R), may serve for fine-tuning of local cytosolic Ca(2+) concentration and mediate numerous membrane-to-membrane interactions within the tubular spongiome meshwork. Such activity is suggested by the occurrence of organelle-specific soluble N-ethylmaleimide sensitive factor attachment protein receptor (SNARE) and Ras-related in brain (Rab) proteins, which may regulate functional requirements. For tubulation, F-Bin-amphiphysin-Rvs (F-BAR) proteins are available. In addition, there is indirect evidence for the occurrence of H(+)/Ca(2+) exchangers (to sequester Ca(2+)) and mechanosensitive Ca(2+)-channels (for signaling the filling sate). The periodic activity of the CVC may be regulated by the mechanosensitive Ca(2+)-channels. Such channels are known to colocalize with and to be functionally supported by stomatins, which were recently detected in the CVC. A Kif18-related kinesin motor protein might control the length of radial arms. Two additional InsP3-related channels and several SNAREs are associated with the pore. De novo organelle biogenesis occurs under epigenetic control during mitotic activity and may involve the assembly of γ-tubulin, centrin, calmodulin and a never in mitosis A-type (NIMA) kinase - components also engaged in mitotic processes.
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Affiliation(s)
- Helmut Plattner
- Department of Biology, University of Konstanz , Konstanz , Germany
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Abstract
Early in evolution, Ca(2+) emerged as the most important second messenger for regulating widely different cellular functions. In eukaryotic cells Ca(2+) signals originate from several sources, i.e. influx from the outside medium, release from internal stores or from both. In mammalian cells, Ca(2+)-release channels represented by inositol 1,4,5-trisphosphate receptors and ryanodine receptors (InsP3R and RyR, respectively) are the most important. In unicellular organisms and plants, these channels are characterised with much less precision. In the ciliated protozoan, Paramecium tetraurelia, 34 molecularly distinct Ca(2+)-release channels that can be grouped in six subfamilies, based on criteria such as domain structure, pore, selectivity filter and activation mechanism have been identified. Some of these channels are genuine InsP3Rs and some are related to RyRs. Others show some--but not all--features that are characteristic for one or the other type of release channel. Localisation and gene silencing experiments revealed widely different--yet distinct--localisation, activation and functional engagement of the different Ca(2+)-release channels. Here, we shall discuss early evolutionary routes of Ca(2+)-release machinery in protozoa and demonstrate that detailed domain analyses and scrutinised functional analyses are instrumental for in-depth evolutionary mapping of Ca(2+)-release channels in unicellular organisms.
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Affiliation(s)
- Helmut Plattner
- Faculty of Biology, University of Konstanz, 78457 Konstanz, Germany.
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Hashimoto M, Enomoto M, Morales J, Kurebayashi N, Sakurai T, Hashimoto T, Nara T, Mikoshiba K. Inositol 1,4,5-trisphosphate receptor regulates replication, differentiation, infectivity and virulence of the parasitic protist Trypanosoma cruzi. Mol Microbiol 2013; 87:1133-50. [PMID: 23320762 DOI: 10.1111/mmi.12155] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/09/2013] [Indexed: 11/26/2022]
Abstract
In animals, inositol 1,4,5-trisphosphate receptors (IP3 Rs) are ion channels that play a pivotal role in many biological processes by mediating Ca(2+) release from the endoplasmic reticulum. Here, we report the identification and characterization of a novel IP3 R in the parasitic protist, Trypanosoma cruzi, the pathogen responsible for Chagas disease. DT40 cells lacking endogenous IP3 R genes expressing T. cruzi IP3 R (TcIP3 R) exhibited IP3 -mediated Ca(2+) release from the ER, and demonstrated receptor binding to IP3 . TcIP3 R was expressed throughout the parasite life cycle but the expression level was much lower in bloodstream trypomastigotes than in intracellular amastigotes or epimastigotes. Disruption of two of the three TcIP3 R gene loci led to the death of the parasite, suggesting that IP3 R is essential for T. cruzi. Parasites expressing reduced or increased levels of TcIP3 R displayed defects in growth, transformation and infectivity, indicating that TcIP3 R is an important regulator of the parasite's life cycle. Furthermore, mice infected with T. cruzi expressing reduced levels of TcIP3 R exhibited a reduction of disease symptoms, indicating that TcIP3 R is an important virulence factor. Combined with the fact that the primary structure of TcIP3 R has low similarity to that of mammalian IP3 Rs, TcIP3 R is a promising drug target for Chagas disease.
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Affiliation(s)
- Muneaki Hashimoto
- Department of Molecular and Cellular Parasitology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
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Acidocalcisomes of Trypanosoma brucei have an inositol 1,4,5-trisphosphate receptor that is required for growth and infectivity. Proc Natl Acad Sci U S A 2013; 110:1887-92. [PMID: 23319604 DOI: 10.1073/pnas.1216955110] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Acidocalcisomes are acidic calcium stores rich in polyphosphate and found in a diverse range of organisms. The mechanism of Ca(2+) release from these organelles was unknown. Here we present evidence that Trypanosoma brucei acidocalcisomes possess an inositol 1,4,5-trisphosphate receptor (TbIP(3)R) for Ca(2+) release. Localization studies in cell lines expressing TbIP(3)R in its endogenous locus fused to an epitope tag revealed its partial colocalization with the vacuolar proton pyrophosphatase, a marker of acidocalcisomes. IP(3) was able to stimulate Ca(2+) release from a chicken B-lymphocyte cell line in which the genes for all three vertebrate IP(3)Rs have been stably ablated (DT40-3KO) and that were stably expressing TbIP(3)R, providing evidence of its function. IP(3) was also able to release Ca(2+) from permeabilized trypanosomes or isolated acidocalcisomes and photolytic release of IP(3) in intact trypanosomes loaded with Fluo-4 elicited a transient Ca(2+) increase in their cytosol. Ablation of TbIP(3)R by RNA interference caused a significant reduction of IP(3)-mediated Ca(2+) release in trypanosomes and resulted in defects in growth in culture and infectivity in mice. Taken together, the data provide evidence of the presence of a functional IP(3)R as a Ca(2+) release channel in acidocalcisomes of trypanosomes and suggest that a Ca(2+) signaling pathway that involves acidocalcisomes is required for growth and establishment of infection.
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Contractile Vacuole Complex—Its Expanding Protein Inventory. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 306:371-416. [DOI: 10.1016/b978-0-12-407694-5.00009-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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New insights into roles of acidocalcisomes and contractile vacuole complex in osmoregulation in protists. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 305:69-113. [PMID: 23890380 DOI: 10.1016/b978-0-12-407695-2.00002-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
While free-living protists are usually subjected to hyposmotic environments, parasitic protists are also in contact with hyperosmotic habitats. Recent work in one of these parasites, Trypanosoma cruzi, has revealed that its contractile vacuole complex, which usually collects and expels excess water as a mechanism of regulatory volume decrease after hyposmotic stress, has also a role in cell shrinking when the cells are submitted to hyperosmotic stress. Trypanosomes also have an acidic calcium store rich in polyphosphate (polyP), named the acidocalcisome, which is involved in their response to osmotic stress. Here, we review newly emerging insights on the role of acidocalcisomes and the contractile vacuole complex in the cellular response to hyposmotic and hyperosmotic stresses. We also review the current state of knowledge on the composition of these organelles and their other roles in calcium homeostasis and protein trafficking.
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Schönemann B, Bledowski A, Sehring IM, Plattner H. A set of SNARE proteins in the contractile vacuole complex of Paramecium regulates cellular calcium tolerance and also contributes to organelle biogenesis. Cell Calcium 2012; 53:204-16. [PMID: 23280185 DOI: 10.1016/j.ceca.2012.11.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 11/15/2012] [Accepted: 11/29/2012] [Indexed: 02/07/2023]
Abstract
The contractile vacuole complex (CVC) of freshwater protists serves the extrusion of water and ions, including Ca(2+). No vesicle trafficking based on SNAREs has been detected so far in any CVC. SNAREs (soluble NSF [N-ethylmaleimide sensitive factor] attachment protein receptors) are required for membrane-to-membrane interaction, i.e. docking and fusion also in Paramecium. We have identified three v-/R- and three t/Q-SNAREs selectively in the CVC. Posttranscriptional silencing of Syb2, Syb6 or Syx2 slows down the pumping cycle; silencing of the latter two also causes vacuole swelling. Increase in extracellular Ca(2+) after Syb2, Syb6 or Syx2 silencing causes further swelling of the contractile vacuole and deceleration of its pulsation. Silencing of Syx14 or Syx15 entails lethality in the Ca(2+) stress test. Thus, the effects of silencing strictly depend on the type of the silenced SNARE and on the concentration of Ca(2+) in the medium. This shows the importance of organelle-resident SNARE functions (which may encompass the vesicular delivery of other organelle-resident proteins) for Ca(2+) tolerance. A similar principle may be applicable also to the CVC in widely different unicellular organisms. In addition, in Paramecium, silencing particularly of Syx6 causes aberrant positioning of the CVC during de novo biogenesis before cytokinesis.
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Plattner H, Sehring IM, Mohamed IK, Miranda K, De Souza W, Billington R, Genazzani A, Ladenburger EM. Calcium signaling in closely related protozoan groups (Alveolata): non-parasitic ciliates (Paramecium, Tetrahymena) vs. parasitic Apicomplexa (Plasmodium, Toxoplasma). Cell Calcium 2012; 51:351-82. [PMID: 22387010 DOI: 10.1016/j.ceca.2012.01.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 01/10/2012] [Accepted: 01/12/2012] [Indexed: 12/20/2022]
Abstract
The importance of Ca2+-signaling for many subcellular processes is well established in higher eukaryotes, whereas information about protozoa is restricted. Recent genome analyses have stimulated such work also with Alveolates, such as ciliates (Paramecium, Tetrahymena) and their pathogenic close relatives, the Apicomplexa (Plasmodium, Toxoplasma). Here we compare Ca2+ signaling in the two closely related groups. Acidic Ca2+ stores have been characterized in detail in Apicomplexa, but hardly in ciliates. Two-pore channels engaged in Ca2+-release from acidic stores in higher eukaryotes have not been stingently characterized in either group. Both groups are endowed with plasma membrane- and endoplasmic reticulum-type Ca2+-ATPases (PMCA, SERCA), respectively. Only recently was it possible to identify in Paramecium a number of homologs of ryanodine and inositol 1,3,4-trisphosphate receptors (RyR, IP3R) and to localize them to widely different organelles participating in vesicle trafficking. For Apicomplexa, physiological experiments suggest the presence of related channels although their identity remains elusive. In Paramecium, IP3Rs are constitutively active in the contractile vacuole complex; RyR-related channels in alveolar sacs are activated during exocytosis stimulation, whereas in the parasites the homologous structure (inner membrane complex) may no longer function as a Ca2+ store. Scrutinized comparison of the two closely related protozoan phyla may stimulate further work and elucidate adaptation to parasitic life. See also "Conclusions" section.
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Affiliation(s)
- H Plattner
- Department of Biology, University of Konstanz, P.O. Box 5560, 78457 Konstanz, Germany.
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41
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Wloga D, Frankel J. From Molecules to Morphology: Cellular Organization of Tetrahymena thermophila. Methods Cell Biol 2012; 109:83-140. [DOI: 10.1016/b978-0-12-385967-9.00005-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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42
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Ryanodine receptor calcium release channels: an evolutionary perspective. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 740:159-82. [PMID: 22453942 DOI: 10.1007/978-94-007-2888-2_7] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Ryanodine receptors (RyRs), along with the related inositol 1,4,5-trisphosphate receptors (IP(3)Rs), mediate the release of Ca(2+) from intracellular organelles of eukaryotes. As discussed in other chapters, such increases in intracellular Ca(2+) levels act a fundamental second messenger, regulating a diverse array of cellular processes. For over two decades, it has been reported that vertebrates express multiple RYR genes, whereas non-vertebrate multicellular organisms possess a single homologue within their genomes. Recently, the existence of RyR-like channels in unicellular organisms has also been reported. This chapter exploits recent expansions in available genome data to generate an overview of the expression of RyR-like genes in organisms representing a broad range of viral, archaeal, bacterial and eukaryotic taxa. Analyses of the multidomain structures and phylogenetic relationships of these proteins has lead to a model in which, early during eukaryotic evolution, IP(3)R-like ancestral Ca(2+) release channels were converted to RyR proteins via the addition of promiscuous protein domains, possibly via horizontal gene transfer mechanisms.
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Calcium-release channels in paramecium. Genomic expansion, differential positioning and partial transcriptional elimination. PLoS One 2011; 6:e27111. [PMID: 22102876 PMCID: PMC3213138 DOI: 10.1371/journal.pone.0027111] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Accepted: 10/10/2011] [Indexed: 11/20/2022] Open
Abstract
The release of Ca2+ from internal stores is a major source of signal Ca2+ in almost all cell types. The internal Ca2+ pools are activated via two main families of intracellular Ca2+-release channels, the ryanodine and the inositol 1,4,5-trisphosphate (InsP3) receptors. Among multicellular organisms these channel types are ubiquitous, whereas in most unicellular eukaryotes the identification of orthologs is impaired probably due to evolutionary sequence divergence. However, the ciliated protozoan Paramecium allowed us to prognosticate six groups, with a total of 34 genes, encoding proteins with characteristics typical of InsP3 and ryanodine receptors by BLAST search of the Paramecium database. We here report that these Ca2+-release channels may display all or only some of the characteristics of canonical InsP3 and ryanodine receptors. In all cases, prediction methods indicate the presence of six trans-membrane regions in the C-terminal domains, thus corresponding to canonical InsP3 receptors, while a sequence homologous to the InsP3-binding domain is present only in some types. Only two types have been analyzed in detail previously. We now show, by using antibodies and eventually by green fluorescent protein labeling, that the members of all six groups localize to distinct organelles known to participate in vesicle trafficking and, thus, may provide Ca2+ for local membrane-membrane interactions. Whole genome duplication can explain radiation within the six groups. Comparative and evolutionary evaluation suggests derivation from a common ancestor of canonical InsP3 and ryanodine receptors. With one group we could ascertain, to our knowledge for the first time, aberrant splicing in one thoroughly analyzed Paramecium gene. This yields truncated forms and, thus, may indicate a way to pseudogene formation. No comparable analysis is available for any other, free-living or parasitic/pathogenic protozoan.
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Prole DL, Taylor CW. Identification of intracellular and plasma membrane calcium channel homologues in pathogenic parasites. PLoS One 2011; 6:e26218. [PMID: 22022573 PMCID: PMC3194816 DOI: 10.1371/journal.pone.0026218] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Accepted: 09/22/2011] [Indexed: 11/29/2022] Open
Abstract
Ca2+ channels regulate many crucial processes within cells and their abnormal activity can be damaging to cell survival, suggesting that they might represent attractive therapeutic targets in pathogenic organisms. Parasitic diseases such as malaria, leishmaniasis, trypanosomiasis and schistosomiasis are responsible for millions of deaths each year worldwide. The genomes of many pathogenic parasites have recently been sequenced, opening the way for rational design of targeted therapies. We analyzed genomes of pathogenic protozoan parasites as well as the genome of Schistosoma mansoni, and show the existence within them of genes encoding homologues of mammalian intracellular Ca2+ release channels: inositol 1,4,5-trisphosphate receptors (IP3Rs), ryanodine receptors (RyRs), two-pore Ca2+ channels (TPCs) and intracellular transient receptor potential (Trp) channels. The genomes of Trypanosoma, Leishmania and S. mansoni parasites encode IP3R/RyR and Trp channel homologues, and that of S. mansoni additionally encodes a TPC homologue. In contrast, apicomplexan parasites lack genes encoding IP3R/RyR homologues and possess only genes encoding TPC and Trp channel homologues (Toxoplasma gondii) or Trp channel homologues alone. The genomes of parasites also encode homologues of mammalian Ca2+influx channels, including voltage-gated Ca2+ channels and plasma membrane Trp channels. The genome of S. mansoni also encodes Orai Ca2+ channel and STIM Ca2+ sensor homologues, suggesting that store-operated Ca2+ entry may occur in this parasite. Many anti-parasitic agents alter parasite Ca2+ homeostasis and some are known modulators of mammalian Ca2+ channels, suggesting that parasite Ca2+ channel homologues might be the targets of some current anti-parasitic drugs. Differences between human and parasite Ca2+ channels suggest that pathogen-specific targeting of these channels may be an attractive therapeutic prospect.
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Affiliation(s)
- David L Prole
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom.
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45
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Leondaritis G, Galanopoulou D. Emerging roles of phosphoinositide-specific phospholipases C in the ciliates Tetrahymena and Paramecium. Commun Integr Biol 2011; 4:576-8. [PMID: 22046467 DOI: 10.4161/cib.4.5.16295] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Accepted: 05/04/2011] [Indexed: 11/19/2022] Open
Abstract
Phospholipases C (PLCs) that hydrolyze inositol phospholipids regulate vital cellular functions in both eukaryotic and prokaryotic organisms. The PLC superfamily consists of eukaryotic phosphoinositide-specific PLCs (PI-PLCs), bacterial PLCs and trypanosomal PLCs.1 PI-PLCs hydrolyze phosphatidylinositol-4,5-bisphosphate (PtdIns4,5P(2)) to produce inositol-1,4,5-trisphosphate (Ins1,4,5P(3)) and constitute a hallmark feature of eukaryotic cells. In metazoa, this reaction is coupled to receptor signaling via specific PI-PLC isoforms and results in acute increase of cytosolic Ca(2+) levels by Ins1,4,5P(3)-sensitive Ca(2+) channels (IP(3)-receptors, IP3Rs).2 A striking result of many studies so far has been the presence of a single PI-PLC gene in all unicellular eukaryotes investigated, as opposed to expansion of PI-PLC isoforms in metazoa;3 this has suggested that a single housekeeping PI-PLC represents an archetypal and simplified form of PI-PLC signaling.3 Several studies however have noted a unique expansion of PI-PLC/IP3R pathway components in ciliates.4,5 In a recent paper we showed the presence of multiple functional PI-PLC genes in Tetrahymena thermophila and biochemical characterization, pharmacological studies and study of their expression patterns suggested that they are likely to serve distinct non-redundant roles.4 In this report we discuss these studies and how they advance our understanding of PI-PLC functions in ciliates.
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Affiliation(s)
- George Leondaritis
- Department of Pharmacology; Medical School; University of Thessaly; Larissa Greece
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Cai X, Clapham DE. Ancestral Ca2+ signaling machinery in early animal and fungal evolution. Mol Biol Evol 2011; 29:91-100. [PMID: 21680871 PMCID: PMC4037924 DOI: 10.1093/molbev/msr149] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Animals and fungi diverged from a common unicellular ancestor of Opisthokonta, yet they exhibit significant differences in their components of Ca2+ signaling pathways. Many Ca2+ signaling molecules appear to be either animal-specific or fungal-specific, which is generally believed to result from lineage-specific adaptations to distinct physiological requirements. Here, by analyzing the genomic data from several close relatives of animals and fungi, we demonstrate that many components of animal and fungal Ca2+ signaling machineries are present in the apusozoan protist Thecamonas trahens, which belongs to the putative unicellular sister group to Opisthokonta. We also identify the conserved portion of Ca2+ signaling molecules in early evolution of animals and fungi following their divergence. Furthermore, our results reveal the lineage-specific expansion of Ca2+ channels and transporters in the unicellular ancestors of animals and in basal fungi. These findings provide novel insights into the evolution and regulation of Ca2+ signaling critical for animal and fungal biology.
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Affiliation(s)
- Xinjiang Cai
- Molecular Pathogenesis Program, The Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, NY, USA.
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Collins SR, Meyer T. Evolutionary origins of STIM1 and STIM2 within ancient Ca2+ signaling systems. Trends Cell Biol 2011; 21:202-11. [PMID: 21288721 PMCID: PMC3175768 DOI: 10.1016/j.tcb.2011.01.002] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2010] [Revised: 12/17/2010] [Accepted: 01/04/2011] [Indexed: 11/26/2022]
Abstract
Human stromal interaction molecule (STIM) proteins are parts of elaborate eukaryotic Ca(2+) signaling systems that include numerous plasma membrane (PM), endoplasmic reticulum (ER), and mitochondrial Ca(2+) transporters, channels and regulators. STIM2 and STIM1 function as Ca(2+) sensors with different sensitivities for ER Ca(2+). They translocate to ER-PM junctions and open PM Orai Ca(2+) influx channels when receptor-mediated Ca(2+) release lowers ER Ca(2+) levels. The resulting increase in cytosolic Ca(2+) leads to the activation of numerous Ca(2+) effector proteins that in turn regulate differentiation, cell contraction, secretion and other cell functions. In this review, we use an evolutionary perspective to survey molecular activation mechanisms in the Ca(2+) signaling system, with a particular focus on regulatory motifs and functions of the two STIM proteins. We discuss the presence and absence of STIM genes in different species, the order of appearance of STIM versus Orai, and the evolutionary addition of new signaling domains to STIM proteins.
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Affiliation(s)
- Sean R Collins
- Department of Chemical and Systems Biology, Stanford University, 318 Campus Drive, Clark Building W2.1, Stanford, CA 94305-5174, USA
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48
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Ulrich PN, Jimenez V, Park M, Martins VP, Atwood J, Moles K, Collins D, Rohloff P, Tarleton R, Moreno SNJ, Orlando R, Docampo R. Identification of contractile vacuole proteins in Trypanosoma cruzi. PLoS One 2011; 6:e18013. [PMID: 21437209 PMCID: PMC3060929 DOI: 10.1371/journal.pone.0018013] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Accepted: 02/22/2011] [Indexed: 11/19/2022] Open
Abstract
Contractile vacuole complexes are critical components of cell volume regulation
and have been shown to have other functional roles in several free-living
protists. However, very little is known about the functions of the contractile
vacuole complex of the parasite Trypanosoma cruzi, the
etiologic agent of Chagas disease, other than a role in osmoregulation.
Identification of the protein composition of these organelles is important for
understanding their physiological roles. We applied a combined proteomic and
bioinfomatic approach to identify proteins localized to the contractile vacuole.
Proteomic analysis of a T. cruzi fraction enriched for
contractile vacuoles and analyzed by one-dimensional gel electrophoresis and
LC-MS/MS resulted in the addition of 109 newly detected proteins to the group of
expressed proteins of epimastigotes. We also identified different peptides that
map to at least 39 members of the dispersed gene family 1 (DGF-1) providing
evidence that many members of this family are simultaneously expressed in
epimastigotes. Of the proteins present in the fraction we selected several
homologues with known localizations in contractile vacuoles of other organisms
and others that we expected to be present in these vacuoles on the basis of
their potential roles. We determined the localization of each by expression as
GFP-fusion proteins or with specific antibodies. Six of these putative proteins
(Rab11, Rab32, AP180, ATPase subunit B, VAMP1, and phosphate transporter)
predominantly localized to the vacuole bladder. TcSNARE2.1, TcSNARE2.2, and
calmodulin localized to the spongiome. Calmodulin was also cytosolic. Our
results demonstrate the utility of combining subcellular fractionation,
proteomic analysis, and bioinformatic approaches for localization of organellar
proteins that are difficult to detect with whole cell methodologies. The CV
localization of the proteins investigated revealed potential novel roles of
these organelles in phosphate metabolism and provided information on the
potential participation of adaptor protein complexes in their biogenesis.
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Affiliation(s)
- Paul N. Ulrich
- Center for Tropical and Emerging Global
Diseases and Department of Cellular Biology, University of Georgia, Athens,
Georgia, United States of America
| | - Veronica Jimenez
- Center for Tropical and Emerging Global
Diseases and Department of Cellular Biology, University of Georgia, Athens,
Georgia, United States of America
| | - Miyoung Park
- Center for Tropical and Emerging Global
Diseases and Department of Cellular Biology, University of Georgia, Athens,
Georgia, United States of America
| | - Vicente P. Martins
- Center for Tropical and Emerging Global
Diseases and Department of Cellular Biology, University of Georgia, Athens,
Georgia, United States of America
| | - James Atwood
- Complex Carbohydrate Research Center,
University of Georgia, Athens, Georgia, United States of America
| | - Kristen Moles
- Center for Tropical and Emerging Global
Diseases and Department of Cellular Biology, University of Georgia, Athens,
Georgia, United States of America
| | - Dalis Collins
- Center for Tropical and Emerging Global
Diseases and Department of Cellular Biology, University of Georgia, Athens,
Georgia, United States of America
| | - Peter Rohloff
- Center for Tropical and Emerging Global
Diseases and Department of Cellular Biology, University of Georgia, Athens,
Georgia, United States of America
| | - Rick Tarleton
- Center for Tropical and Emerging Global
Diseases and Department of Cellular Biology, University of Georgia, Athens,
Georgia, United States of America
| | - Silvia N. J. Moreno
- Center for Tropical and Emerging Global
Diseases and Department of Cellular Biology, University of Georgia, Athens,
Georgia, United States of America
| | - Ron Orlando
- Complex Carbohydrate Research Center,
University of Georgia, Athens, Georgia, United States of America
| | - Roberto Docampo
- Center for Tropical and Emerging Global
Diseases and Department of Cellular Biology, University of Georgia, Athens,
Georgia, United States of America
- * E-mail:
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49
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Biochemical and genetic evidence for the presence of multiple phosphatidylinositol- and phosphatidylinositol 4,5-bisphosphate-specific phospholipases C in Tetrahymena. EUKARYOTIC CELL 2010; 10:412-22. [PMID: 21169416 DOI: 10.1128/ec.00272-10] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Eukaryotic phosphoinositide-specific phospholipases C (PI-PLC) specifically hydrolyze phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P(2)], produce the Ca(2+)-mobilizing agent inositol 1,4,5-trisphosphate, and regulate signaling in multicellular organisms. Bacterial PtdIns-specific PLCs, also present in trypanosomes, hydrolyze PtdIns and glycosyl-PtdIns, and they are considered important virulence factors. All unicellular eukaryotes studied so far contain a single PI-PLC-like gene. In this report, we show that ciliates are an exception, since we provide evidence that Tetrahymena species contain two sets of functional genes coding for both bacterial and eukaryotic PLCs. Biochemical characterization revealed two PLC activities that differ in their phosphoinositide substrate utilization, subcellular localization, secretion to extracellular space, and sensitivity to Ca(2+). One of these activities was identified as a typical membrane-associated PI-PLC activated by low-micromolar Ca(2+), modestly activated by GTPγS in vitro, and inhibited by the compound U73122 [1-(6-{[17β-3-methoxyestra-1,3,5(10)-trien-17-yl]amino}hexyl)-1H-pyrrole-2,5-dione]. Importantly, inhibition of PI-PLC in vivo resulted in rapid upregulation of PtdIns(4,5)P(2) levels, suggesting its functional importance in regulating phosphoinositide turnover in Tetrahymena. By in silico and molecular analysis, we identified two PLC genes that exhibit significant similarity to bacterial but not trypanosomal PLC genes and three eukaryotic PI-PLC genes, one of which is a novel inactive PLC similar to proteins identified only in metazoa. Comparative studies of expression patterns and PI-PLC activities in three T. thermophila strains showed a correlation between expression levels and activity, suggesting that the three eukaryotic PI-PLC genes are functionally nonredundant. Our findings imply the presence of a conserved and elaborate PI-PLC-Ins(1,4,5)P(3)-Ca(2+) regulatory axis in ciliates.
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50
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Verret F, Wheeler G, Taylor AR, Farnham G, Brownlee C. Calcium channels in photosynthetic eukaryotes: implications for evolution of calcium-based signalling. THE NEW PHYTOLOGIST 2010; 187:23-43. [PMID: 20456068 DOI: 10.1111/j.1469-8137.2010.03271.x] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Much of our current knowledge on the mechanisms by which Ca(2+) signals are generated in photosynthetic eukaryotes comes from studies of a relatively small number of model species, particularly green plants and algae, revealing some common features and notable differences between 'plant' and 'animal' systems. Physiological studies from a broad range of algal cell types have revealed the occurrence of animal-like signalling properties, including fast action potentials and fast propagating cytosolic Ca(2+) waves. Genomic studies are beginning to reveal the widespread occurrence of conserved channel types likely to be involved in Ca(2+) signalling. However, certain widespread 'ancient' channel types appear to have been lost by certain groups, such as the embryophytes. More recent channel gene loss is also evident from comparisons of more closely related algal species. The underlying processes that have given rise to the current distributions of Ca(2+) channel types include widespread retention of ancient Ca(2+) channel genes, horizontal gene transfer (including symbiotic gene transfer and acquisition of bacterial genes), gene loss and gene expansion within taxa. The assessment of the roles of Ca(2+) channel genes in diverse physiological, developmental and life history processes represents a major challenge for future studies.
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Affiliation(s)
- Frédéric Verret
- Marine Biological Association of the UK, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| | - Glen Wheeler
- Marine Biological Association of the UK, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
- Plymouth Marine Laboratory, Prospect Place, The Hoe, Plymouth PL1 3DH, UK
| | - Alison R Taylor
- Department of Biology and Marine Biology, University of North Carolina, 601 S. College Road, Wilmington, NC 28403, USA
| | - Garry Farnham
- Plymouth Marine Laboratory, Prospect Place, The Hoe, Plymouth PL1 3DH, UK
| | - Colin Brownlee
- Marine Biological Association of the UK, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
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