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Guerrier S, Plattner H, Richardson E, Dacks JB, Turkewitz AP. An evolutionary balance: conservation vs innovation in ciliate membrane trafficking. Traffic 2016; 18:18-28. [PMID: 27696651 DOI: 10.1111/tra.12450] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 09/20/2016] [Accepted: 09/20/2016] [Indexed: 12/15/2022]
Abstract
As most of eukaryotic diversity lies in single-celled protists, they represent unique opportunities to ask questions about the balance of conservation and innovation in cell biological features. Among free-living protists the ciliates offer ease of culturing, a rich array of experimental approaches, and versatile molecular tools, particularly in Tetrahymena thermophila and Paramecium tetraurelia. These attributes have been exploited by researchers to analyze a wealth of cellular structures in these large and complex cells. This mini-review focuses on 3 aspects of ciliate membrane dynamics, all linked with endolysosomal trafficking. First is nutrition based on phagocytosis and maturation of food vacuoles. Secondly, we discuss regulated exocytosis from vesicles that have features of both dense core secretory granules but also lysosome-related organelles. The third topic is the targeting, breakdown and resorption of parental nuclei in mating partners. For all 3 phenomena, it is clear that elements of the canonical membrane-trafficking system have been retained and in some cases repurposed. In addition, there is evidence that recently evolved, lineage-specific proteins provide determinants in these pathways.
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Affiliation(s)
| | - Helmut Plattner
- Department of Biology, University of Konstanz, Konstanz, Germany
| | | | - Joel B Dacks
- Department of Cell Biology, University of Alberta, Canada
| | - Aaron P Turkewitz
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois
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2
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Kissmehl R, Sehring IM, Wagner E, Plattner H. Immunolocalization of Actin in Paramecium Cells. J Histochem Cytochem 2016; 52:1543-59. [PMID: 15557210 DOI: 10.1369/jhc.4a6379.2004] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We have selected a conserved immunogenic region from several actin genes of Paramecium, recently cloned in our laboratory, to prepare antibodies for Western blots and immunolocalization. According to cell fractionation analysis, most actin is structure-bound. Immunofluorescence shows signal enriched in the cell cortex, notably around ciliary basal bodies (identified by anti-centrin antibodies), as well as around the oral cavity, at the cytoproct and in association with vacuoles (phagosomes) up to several μm in size. Subtle strands run throughout the cell body. Postembedding immunogold labeling/EM analysis shows that actin in the cell cortex emanates, together with the infraciliary lattice, from basal bodies to around trichocyst tips. Label was also enriched around vacuoles and vesicles of different size including “discoidal” vesicles that serve the formation of new phagosomes. By all methods used, we show actin in cilia. Although none of the structurally well-defined filament systems in Paramecium are exclusively formed by actin, actin does display some ordered, though not very conspicuous, arrays throughout the cell. F-actin may somehow serve vesicle trafficking and as a cytoplasmic scaffold. This is particularly supported by the postembedding/EM labeling analysis we used, which would hardly allow for any large-scale redistribution during preparation.
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Affiliation(s)
- Roland Kissmehl
- Department of Biology, University of Konstanz, PO Box 5560, 78457 Konstanz, Germany
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3
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Blum M, Feistel K, Thumberger T, Schweickert A. The evolution and conservation of left-right patterning mechanisms. Development 2014; 141:1603-13. [PMID: 24715452 DOI: 10.1242/dev.100560] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Morphological asymmetry is a common feature of animal body plans, from shell coiling in snails to organ placement in humans. The signaling protein Nodal is key for determining this laterality. Many vertebrates, including humans, use cilia for breaking symmetry during embryonic development: rotating cilia produce a leftward flow of extracellular fluids that induces the asymmetric expression of Nodal. By contrast, Nodal asymmetry can be induced flow-independently in invertebrates. Here, we ask when and why flow evolved. We propose that flow was present at the base of the deuterostomes and that it is required to maintain organ asymmetry in otherwise perfectly bilaterally symmetrical vertebrates.
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Affiliation(s)
- Martin Blum
- Institute of Zoology, University of Hohenheim, 70593 Stuttgart, Germany
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4
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Plattner H. How to Design a Highly Organized Cell: An Unexpectedly High Number of Widely Diversified SNARE Proteins Positioned at Strategic Sites in the Ciliate, Paramecium tetraurelia. Protist 2010; 161:497-516. [DOI: 10.1016/j.protis.2010.05.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Plattner H. Membrane Trafficking in Protozoa. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2010; 280:79-184. [DOI: 10.1016/s1937-6448(10)80003-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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6
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Ramoino P, Usai C, Maccione S, Beltrame F, Diaspro A, Fato M, Guella G, Dini F. Effect of the bioactive metabolite euplotin C on phagocytosis and fluid-phase endocytosis in the single-celled eukaryote Paramecium. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2007; 85:67-75. [PMID: 17875329 DOI: 10.1016/j.aquatox.2007.08.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2007] [Revised: 08/02/2007] [Accepted: 08/03/2007] [Indexed: 05/17/2023]
Abstract
The effect of euplotin C -- a lipophilic bioactive metabolite produced by the ciliate Euplotes crassus -- on the kinetics of both phagocytosis of latex particles and fluid-phase uptake of dextran, was studied in the single-cell ciliate Paramecium primaurelia. The inhibition of food vacuole formation was concentration- and time-dependent (p<0.001), even if euplotin C did not completely block the phagocytosis. Following a 15 min treatment with a euplotin C (0.5 microg/ml), the latex particle uptake was inhibited up to 25%. Furthermore, the pretreatment of cells with taxol strongly counteracted euplotin C effect. The amount of extracellularly provided dextran, which is internalized exclusively by fluid-phase uptake, was quantified in cells whose phagocytic activity was blocked by trifluoperazine. The amount of the internalized dextran was about 50% of that in controls after 15 min incubation in the presence of euplotin C. Fluorescence confocal images showed that no endosomes were formed on the surface of these cells. The effect of euplotin C on the food vacuole formation and fluid-phase endocytosis is apparently mediated by a modification of microtubule network.
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Affiliation(s)
- Paola Ramoino
- Dipartimento per lo Studio del Territorio e delle sue Risorse (DIP.TE.RIS.), Università di Genova, Corso Europa 26, I-16132, Genova, Italy.
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7
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Sehring IM, Reiner C, Mansfeld J, Plattner H, Kissmehl R. A broad spectrum of actin paralogs inParamecium tetraureliacells display differential localization and function. J Cell Sci 2007; 120:177-90. [PMID: 17164292 DOI: 10.1242/jcs.03313] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
To localize the different actin paralogs found in Paramecium and to disclose functional implications, we used overexpression of GFP-fusion proteins and antibody labeling, as well as gene silencing. Several isoforms are associated with food vacuoles of different stages. GFP-actin either forms a tail at the lee side of the organelle, or it is vesicle bound in a homogenous or in a speckled arrangement, thus reflecting an actin-based mosaic of the phagosome surface appropriate for association and/or dissociation of other vesicles upon travel through the cell. Several paralogs occur in cilia. A set of actins is found in the cell cortex where actin outlines the regular surface pattern. Labeling of defined structures of the oral cavity is due to other types of actin, whereas yet more types are distributed in a pattern suggesting association with the numerous Golgi fields. A substantial fraction of actins is associated with cytoskeletal elements that are known to be composed of other proteins. Silencing of the respective actin genes or gene subfamilies entails inhibitory effects on organelles compatible with localization studies. Knock down of the actin found in the cleavage furrow abolishes cell division, whereas silencing of other actin genes alters vitality, cell shape and swimming behavior.
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Affiliation(s)
- Ivonne M Sehring
- Department of Biology, University of Konstanz, P.O. Box 5560, 78457 Konstanz, Germany.
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8
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Abstract
RNA interference can be induced very efficiently by feeding the ciliate Paramecium with bacteria engineered to express double-stranded RNA, opening the possibility of large-scale functional screening in this unicell.
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Ishida M, Allen RD, Fok AK. Phagosome formation in Paramecium: roles of somatic and oral cilia and of solid particles as revealed by video microscopy. J Eukaryot Microbiol 2001; 48:640-6. [PMID: 11831772 DOI: 10.1111/j.1550-7408.2001.tb00203.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The roles of somatic and oral cilia and solid particles during digestive vacuole (DV) formation in Paramecium multimicronucleatum were investigated using video-enhanced and immunofluorescence microscopy. Membrane incorporation into DVs was found to increase linearly with increasing particle concentration. The rate of discoidal vesicle transport to the cytopharynx was not affected by particles, showing that particles are not required for membrane trafficking to the cytopharynx. However, the presence of particles leads to an increased membrane fusion between the cytopharyngeal membrane and the discoidal vesicles. When live cells lost their somatic cilia on the left-ventral side anterior to the oral region due to deciliation, membrane incorporation into newly formed DVs was strongly inhibited. Using video-enhanced microscopy, latex beads were seen to be loaded along the quadrulus on the dorsal surface of the buccal cavity, but few beads were seen next to the dorsal and ventral peniculi. Particle sequestration into a pre-formed nascent digestive vacuole (NDV) was studied in Triton X-100-permeabilized cells whose ciliary beating was reactivated by the addition of Mg-ATP. Both beat frequency and the percentage of cells containing bead-labeled NDV were dependent on the Mg-ATP concentration: the higher the beat frequency, the higher the percentage of cells with a bead-labeled NDV. These results suggest that ciliary beating is probably the only mechanism required for particle accumulation in the NDV, while a coordinated beating of the somatic cilia on the left-ventral side anterior to the oral region as well as the quadrulus moves particles into the NDV. The beating of the peniculi may somehow prevent the backward flow of particles out of the NDV.
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Affiliation(s)
- M Ishida
- Department of Physiology, Mie University School of Medicine, Tsu, Japan
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Zubkov MV, Zöllner E, Jürgens K. Digestion of bacterial macromolecules by a mixotrophic flagellate, Ochromonas sp., compared with that by two heterotrophic flagellates, Spumella pudica and Bodo saltans. Eur J Protistol 2001. [DOI: 10.1078/0932-4739-00815] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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11
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Abstract
Regulated secretion has been traditionally regarded as a specialized process present in only a few cell types. Similarly, the secretory lysosomes of hematopoietic cells have been viewed as 'modified' organelles that acquired the machinery for regulated exocytosis. However, there is evidence that conventional lysosomes can, in many cell types, respond to rises in the intracellular free Ca2+ concentration by fusing with the plasma membrane. These findings profoundly change the current view of lysosomes as a 'final' station of the endocytic pathway and suggest a previously unsuspected active role for this organelle.
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Affiliation(s)
- N W Andrews
- Section of Microbial Pathogenesis, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, CT 06536, USA.
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Allen RD, Fok AK. Membrane trafficking and processing in Paramecium. INTERNATIONAL REVIEW OF CYTOLOGY 2000; 198:277-318. [PMID: 10804465 DOI: 10.1016/s0074-7696(00)98007-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Cellular membranes are made in a cell's biosynthetic pathway and are composed of similar biochemical constituents. Nevertheless, they become differentiated as membrane components are sorted into different membrane-limited compartments. We summarize the morphological and immunological similarities and differences seen in the membranes of the various interacting compartments in the single-celled organism, Paramecium. Besides the biosynthetic pathway, membranes of the regulated secretory pathway, endocytic pathway, and phagocytic pathway are highlighted. Paramecium is a multipolarized cell in the sense that several different pools of membrane-limited compartments are targeted for exocytosis at very specific sites at the cell surface. Thus, the method used by this cell to sort and package its membrane subunits into different compartments, the processes used to transport these compartments to specific locations at the plasma membrane and to other intracellular fusion sites, the processes of membrane retrieval, and the processes of membrane docking and fusion are reviewed. Paramecium has provided an excellent model for studying the complexities of membrane trafficking in one cell using both morphological and immunocytochemical techniques. This cell also promises to be a useful model for studying aspects of the molecular biology of membrane sorting, retrieval, transport, and fusion.
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Affiliation(s)
- R D Allen
- Pacific Biomedical Research Center, Department of Microbiology, University of Hawaii, Manoa, USA
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13
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Baumert U, Vosskühler C, Tiedtke A. Formation and maturation of phagosomes labeled by magnetic micro particles: an ultrastructural study in Tetrahymena thermophila. Eur J Protistol 1998. [DOI: 10.1016/s0932-4739(98)80056-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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14
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GROVER JOHNE, ROPE ALANF, KANESHIRO EDNAS. The Occurrence of Biogenic Calcian Struvite, (Mg, Ca)NH4PO4.6H2O, as Intracellular Crystals in Paramecium. J Eukaryot Microbiol 1997. [DOI: 10.1111/j.1550-7408.1997.tb05679.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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15
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Ramoino P, Beltrame F, Diaspro A, Fato M. Time-variant analysis of organelle and vesicle movement during phagocytosis in Paramecium primaurelia by means of fluorescence confocal laser scanning microscopy. Microsc Res Tech 1996; 35:377-84. [PMID: 8989767 DOI: 10.1002/(sici)1097-0029(19961201)35:5<377::aid-jemt2>3.0.co;2-i] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Vital fluorescent dyes (FITC-albumin, Texas Red-albumin, and acridine orange) were used together with a confocal laser scanning optical microscope (CLSM) to display and analyze formation, movement, and fusion of vesicles during the phagocytosis of Paramecium primaurelia, in the x-y-z-t space. By immobilizing living cells pulsed with a food vacuole marker at successive times after chasing in unlabeled medium, the intracellular movement of food vacuoles from their formation at the cytostome to their egestion at the cytoproct was visualized, and food vacuoles were selected in a specific digestion stage. Small pinocytic vesicles are shown to evaginate from the vacuoles and move in the cytoplasm. These vesicles are transported toward the cytopharynx where they enlarge the membrane of the nascent food vacuoles or fuse with stage II food vacuoles, when the vacuoles of stage II increase their size, changing from an acidic to an alkaline status. A multimodal analysis of confocal fluorescence images and the false-color technique were used to visualize vesicle movement vs. time. Starting from three images of the same cell at succeeding time points, a composite image was generated by associating with each originally acquired image a different color corresponding to each sampling point in time. The composite image shows that vesicles move away from the food vacuole in a scattered manner exhibiting changes in direction.
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Affiliation(s)
- P Ramoino
- Institute of Zoology, University of Genoa, Italy
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16
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Cronkite DL, Lopez R, Walsh J. The effect of hyper-osmotic stress on food vacuole formation in Paramecium tetraurelia and Paramecium calkinsi. Eur J Protistol 1996. [DOI: 10.1016/s0932-4739(96)80070-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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17
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Ramoino P, Beltrame F, Fato M. Image analysis of lysosomal activity during the early clonal life of Paramecium primaurelia. FEMS Microbiol Lett 1995; 125:57-61. [PMID: 7867921 DOI: 10.1111/j.1574-6968.1995.tb07335.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Acid phosphatase activity was measured in individual cells by determining their optical densities through a scanning confocal laser microscope. The naphthol AS-TR (3-hydroxy-2-naphtoic acid 4'-chloro-2'-methylanilide) phosphate-hexazotized para-rosanilin method was used to visualise the acid phosphatase content in the light microscope. Evidence was obtained that the amount of enzyme varied in exponential growth phase cells as the fission age increased. By comparing the acid phosphatase activity with the rate of food vacuole formation, it appeared that the amount of enzyme inside the cells decreased in early clonal life, whereas the rate of food uptake increased. It was assumed that the reduction of acid phosphatase content could lead to a more extended life of vacuoles and to a decreased membrane recycling rate. In turn, the reduced supply of membrane available for food vacuole formation could partly be responsible for the decrease of the food uptake rate observed after the initial increase.
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Affiliation(s)
- P Ramoino
- Institute of Zoology, University of Genoa, Italy
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18
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VOSKÜHLER CHRISTIAN, TIEDTKE ARNO. Magnetic Separation of Phagosomes of Defined Age from Tetrahymena thermophila. J Eukaryot Microbiol 1993. [DOI: 10.1111/j.1550-7408.1993.tb06107.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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19
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20
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Choi EY, Kim KJ, Jeon KW. Lysosomal membrane proteins of Amoeba proteus, as studied with monoclonal antibodies. THE JOURNAL OF PROTOZOOLOGY 1992; 39:671-7. [PMID: 1453355 DOI: 10.1111/j.1550-7408.1992.tb04447.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Monoclonal antibodies were prepared against lysosomal membrane proteins of amoebae and used to follow lysosome-phagosome fusion after induced phagocytosis. The specificity of antibodies was checked by indirect immunofluorescence microscopy, immunoelectron microscopy, and localization of the antigen in subcellular fractions. The antibody-recognized proteins started to appear on the membranes of phagolysosomes about 5 min after phagocytosis as detected by indirect immunofluorescence, and the intensity of fluorescence increased for up to 1 h. Results of injection experiments in which purified antibodies had been injected into living cells and probed by indirect fluorescence indicated that the antigens were located on the cytoplasmic side of the lysosomal membranes. Lysosomes fuse with phagosomes on the one hand but not with non-fusible vesicles such as symbiosomes on the other. The results support the view that a membrane component(s) of non-fusible vesicles somehow prevents lysosomes from fusing with them.
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Affiliation(s)
- E Y Choi
- Department of Zoology, University of Tennessee, Knoxville 37996
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21
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Kaneshiro ES, Reuter SF, Quattrone FJ, Morris RE. Sustained food vacuole formation by axenic Paramecium tetraurelia and the inhibition of membrane recycling by Alcian Blue. THE JOURNAL OF PROTOZOOLOGY 1992; 39:713-8. [PMID: 1280684 DOI: 10.1111/j.1550-7408.1992.tb04453.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
It is believed that the uptake mechanism of some nutrients by Paramecium tetraurelia primarily involves transport through the cell surface, whereas the uptake of other compounds appears to be restricted to bulk transport during food vacuole (phagosome) formation. In this study, we established that, in axenically grown cells, food vacuole formation occurred at continuous rates over long periods. This information allows quantitation of the volume of media taken up by bulk transport. India ink and latex beads were shown to be inert food vacuole markers and carmine was found to have an initial stimulatory effect on phagosome formation rates. Cultures grown for 3.5 h or longer with the glycocalyx stain Alcian Blue, contained only three phagosomes/cell, whereas cells cultured with the other markers contained 15 phagosomes/cell. Electron microscopy of fecal material that accumulated at the bottom of Alcian Blue-grown cells demonstrated the presence of membranes, suggesting that the vacuolar membrane was eliminated during defecation. Neither cell lysis nor the formation of autophagous vacuoles was detected in Alcian Blue-grown cells, indicating that the stain was not cytotoxic at the concentrations used. Thus it appeared that the binding of Alcian Blue to the digestive vacuole membrane resulted in a loss of the vacuole membranes from the cell which reduced the amount of membranes retrieved and recycled and hence eventually reduced the rate of phagosome formation. Alcian Blue-treated cultures exhibited decreased rate of growth and final density, which is consistent with a decrease in bulk transport of nutrients resulting from reduced membranes of digestive cycle organelles available in the cell.
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Affiliation(s)
- E S Kaneshiro
- Department of Biological Sciences, University of Cincinnati, Ohio 45221
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22
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Abstract
The ciliated protists (ciliates) offer a unique opportunity to explore the relationship between chemoreception and cell structure. Ciliates resemble chemosensory neurons in their responses to stimuli and presence of cilia. Ciliates have highly patterned surfaces that should permit precise localization of chemoreceptors in relation to effector organelles. Furthermore, ciliates are easy to grow and to manipulate genetically; they can also be readily studied biochemically and by electrophysiological techniques. This review contains a comparative description of the ultrastructural features of the ciliate cell surface relevant to chemoreception, examines the structural features of putative chemoreceptive cilia, and provides a summary of the electron microscopic information available so far bearing on chemoreceptive aspects of swimming, feeding, excretion, endocytosis, and sexual responses of ciliates. The electron microscopic identification and localization of specific chemoreceptive macromolecules and organelles at the molecular level have not yet been achieved in ciliates. These await the development of specific probes for chemoreceptor and transduction macromolecules. Nevertheless, the electron microscope has provided a wealth of information about the surface features of ciliates where chemoreception is believed to take place. Such morphological information will prove essential to a complete understanding of reception and transduction at the molecular level. In the ciliates, major questions to be answered relate to the apportionment of chemoreceptive functions between the cilia and cell soma, the global distribution of receptors in relation to the anterior-posterior, dorsal-ventral, and left-right axes of the cell, and the relationship of receptors to ultrastructural components of the cell coat, cell membrane, and cytoskeleton.
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Affiliation(s)
- L A Hufnagel
- Department of Microbiology, University of Rhode Island, Kingston 02881
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Raymond CK, Roberts CJ, Moore KE, Howald I, Stevens TH. Biogenesis of the vacuole in Saccharomyces cerevisiae. INTERNATIONAL REVIEW OF CYTOLOGY 1992; 139:59-120. [PMID: 1428679 DOI: 10.1016/s0074-7696(08)61410-2] [Citation(s) in RCA: 89] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- C K Raymond
- Institute of Molecular Biology, University of Oregon, Eugene 97403
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Padh H, Lavasa M, Steck T. Reconstitution of the association of endocytic vacuoles and acidosomes from Dictyostelium. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)98866-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Padh H, Lavasa M, Steck TL. Endosomes are acidified by association with discrete proton-pumping vacuoles in Dictyostelium. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(19)67624-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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26
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Schroeder CC, Fok AK, Allen RD. Vesicle transport along microtubular ribbons and isolation of cytoplasmic dynein from Paramecium. J Biophys Biochem Cytol 1990; 111:2553-62. [PMID: 2148940 PMCID: PMC2116376 DOI: 10.1083/jcb.111.6.2553] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Cytoplasmic microtubule-based motility in Paramecium was investigated using video-enhanced contrast microscopy, the quick-freeze, deep-etch technique, and biochemical isolations. Three distinct vesicle populations were found to be transported unidirectionally along the cytopharyngeal microtubular ribbons. This minus-end-directed movement exhibited unique in vivo features in that the vesicle transport was nonsaltatory, rapid, and predominantly along one side of the microtubular ribbons. To identify candidate motor proteins which may participate in vesicle transport, we prepared cytosolic extracts of Paramecium and used bovine brain microtubules as an affinity matrix. These preparations were found to contain a microtubule-stimulated ATPase which supported microtubule gliding in vitro. This protein was verified as a cytoplasmic dynein based upon its relative molecular mass, sedimentation coefficient of 16S, susceptibility to vanadate photocleavage, elevated CTPase/ATPase ratio, and its typical two-headed dynein morphology. This dynein was directly compared with the axonemal dyneins from Paramecium and found to differ by five criteria: morphology, sedimentation coefficient, CTPase/ATPase ratio, vanadate cleavage patterns, and polypeptide composition. The cytoplasmic dynein is therefore not an axonemal dynein precursor, but rather it represents a candidate for supporting the microtubule-based vesicle transport which proceeds along the microtubular ribbons.
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Affiliation(s)
- C C Schroeder
- Pacific Biomedical Research Center, University of Hawaii, Honolulu 96822
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