scholarly journals THE STRUCTURE OF CELLS DURING TOBACCO MOSAIC VIRUS REPRODUCTION

1965 ◽  
Vol 25 (3) ◽  
pp. 77-97 ◽  
Author(s):  
L. Kolehmainen ◽  
H. Zech ◽  
D. von Wettstein
Keyword(s):  
Endoplasmic Reticulum ◽  
Tobacco Mosaic Virus ◽  
Mosaic Virus ◽  
Electron Scattering ◽  
Osmium Tetroxide ◽  
Crystal Formation ◽  
Mesophyll Cells ◽  
Virus Particles ◽  
Flexible Rods ◽  
Late Stages

The submicroscopic organization of mesophyll cells from tobacco leaves systemically infected with tobacco mosaic virus (TMV) is described. After fixation with glutaraldehyde and osmium tetroxide the arrangement of the TMV particles within the crystalline inclusions is well preserved. Only the ribonucleic acid-containing core of the virus particles is visible in the micrographs. Besides the hexagonal virus crystals, several characteristic types of "inclusion bodies" are definable in the cytoplasm: The so-called fluid crystals seem to correspond to single layers of oriented TMV particles between a network of the endoplasmic reticulum and ribosomes. Unordered groups or well oriented masses of tubes with the diameter of the TMV capsid are found in certain areas of the cytoplasm. A complicated inclusion body is characterized by an extensively branched and folded part of the endoplasmic reticulum, containing in its folds long aggregates of flexible rods. Certain parts of the cytoplasm are filled with large, strongly electron-scattering globules, probably of lipid composition. These various cytoplasmic differentiations and the different forms of presumed virus material are discussed in relation to late stages of TMV reproduction and virus crystal formation.

scholarly journals ASSEMBLY AND AGGREGATION OF TOBACCO MOSAIC VIRUS IN TOMATO LEAFLETS

1964 ◽  
Vol 21 (2) ◽  
pp. 253-264 ◽  
Author(s):  
Thomas A. Shalla
Keyword(s):  
Electron Microscopy ◽  
Tobacco Mosaic Virus ◽  
Mosaic Virus ◽  
Lycopersicum Esculentum ◽  
Rapid Synthesis ◽  
Mesophyll Cells ◽  
Virus Particles ◽  
Particle Aggregates ◽  
Cytological Changes ◽  
Individual Particles

Cells of tomato leaflets (Lycopersicum esculentum Mill.) were studied by phase and electron microscopy at various intervals after inoculation with a common strain of tobacco mosaic virus (TMV). Forty-eight hours after inoculation, prior to the development of assayable virus, individual TMV particles, and also particle aggregates, were observed in the ground cytoplasm of mesophyll cells. The most rapid synthesis of virus occurred between 80 and 300 hours after inoculation. Cytological changes during this time were characterized by an increased number of individual particles in the cytoplasm, growth of some aggregates, distortion and vacuolation of chloroplasts, and formation of filaments in the cytoplasm which were approximately four times the size of TMV. These filaments were interpreted as possible developmental forms of the TMV particle. Vacuoles in chloroplasts commonly contained virus particles. Evidence indicated that TMV was assembled in the ground cytoplasm and, in some cases, subsequently was enveloped by distorted chloroplasts.

scholarly journals RELATION OF TOBACCO MOSAIC VIRUS TO THE HOST CELLS

1967 ◽  
Vol 33 (3) ◽  
pp. 665-678 ◽  
Author(s):  
Katherine Esau ◽  
James Cronshaw
Keyword(s):  
Electron Microscope ◽  
Tobacco Mosaic Virus ◽  
Mosaic Virus ◽  
Host Cells ◽  
Vascular Bundles ◽  
Mesophyll Cells ◽  
Virus Particles ◽  
Nicotiana Tabacum L ◽  
Parenchyma Cells ◽  
Particle Aggregates

The relation of tobacco mosaic virus (TMV) to host cells was studied in leaves of Nicotiana tabacum L. systemically infected with the virus. The typical TMV inclusions, striate or crystalline material and ameboid or X-bodies, which are discernible with the light microscope, and/or particles of virus, which are identifiable with the electron microscope, were observed in epidermal cells, mesophyll cells, parenchyma cells of the vascular bundles, differentiating and mature tracheary elements, and immature and mature sieve elements. Virus particles were observed in the nuclei and the chloroplasts of parenchyma cells as well as in the ground cytoplasm, the vacuole, and between the plasma membrane and the cell wall. The nature of the conformations of the particle aggregates in the chloroplasts was compatible with the concept that some virus particles may be assembled in these organelles. The virus particles in the nuclei appeared to be complete particles. Under the electron microscope the X-body constitutes a membraneless assemblage of endoplasmic reticulum, ribosomes, virus particles, and of virus-related material in the form of wide filaments indistinctly resolvable as bundles of tubules. Some parenchyma cells contained aggregates of discrete tubules in parallel arrangement. These groups of tubules were relatively free from components of host protoplasts.

scholarly journals Structural Transitions of Satellite Tobacco Mosaic Virus Particles

Virology ◽  
2001 ◽  
Vol 284 (2) ◽  
pp. 223-234 ◽  
Author(s):  
Yurii G. Kuznetsov ◽  
Steven B. Larson ◽  
John Day ◽  
Aaron Greenwood ◽  
Alexander McPherson
Keyword(s):  
Tobacco Mosaic Virus ◽  
Mosaic Virus ◽  
Structural Transitions ◽  
Virus Particles ◽  
Satellite Tobacco Mosaic Virus

scholarly journals The 5′ Cap of Tobacco Mosaic Virus (TMV) Is Required for Virion Attachment to the Actin/Endoplasmic Reticulum Network During Early Infection

Traffic ◽  
2009 ◽  
Vol 10 (5) ◽  
pp. 536-551 ◽  
Author(s):  
Nynne Christensen ◽  
Jens Tilsner ◽  
Karen Bell ◽  
Philippe Hammann ◽  
Richard Parton ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Tobacco Mosaic Virus ◽  
Mosaic Virus ◽  
Early Infection

scholarly journals Actin Cytoskeleton Is Involved in Targeting of a Viral Hsp70 Homolog to the Cell Periphery

2005 ◽  
Vol 79 (22) ◽  
pp. 14421-14428 ◽  
Author(s):  
Alexey I. Prokhnevsky ◽  
Valera V. Peremyslov ◽  
Valerian V. Dolja
Keyword(s):  
Actin Cytoskeleton ◽  
Tobacco Mosaic Virus ◽  
Mosaic Virus ◽  
Movement Protein ◽  
Fluorescent Proteins ◽  
Cell Movement ◽  
Plant Viruses ◽  
Cell Periphery ◽  
Virus Particles ◽  
Shock Proteins

ABSTRACT The cell-to-cell movement of plant viruses involves translocation of virus particles or nucleoproteins to and through the plasmodesmata (PDs). As we have shown previously, the movement of the Beet yellows virus requires the concerted action of five viral proteins including a homolog of cellular ∼70-kDa heat shock proteins (Hsp70h). Hsp70h is an integral component of the virus particles and is also found in PDs of the infected cells. Here we investigate subcellular distribution of Hsp70h using transient expression of Hsp70h fused to three spectrally distinct fluorescent proteins. We found that fluorophore-tagged Hsp70h forms motile granules that are associated with actin microfilaments, but not with microtubules. In addition, immobile granules were observed at the cell periphery. A pairwise appearance of these granules at the opposite sides of cell walls and their colocalization with the movement protein of Tobacco mosaic virus indicated an association of Hsp70h with PDs. Treatment with various cytoskeleton-specific drugs revealed that the intact actomyosin motility system is required for trafficking of Hsp70h in cytosol and its targeting to PDs. In contrast, none of the drugs interfered with the PD localization of Tobacco mosaic virus movement protein. Collectively, these findings suggest that Hsp70h is translocated and anchored to PDs in association with the actin cytoskeleton.

Changing Patterns of Localization of the Tobacco Mosaic Virus Movement Protein and Replicase to the Endoplasmic Reticulum and Microtubules during Infection

1998 ◽  
Vol 10 (7) ◽  
pp. 1107 ◽  
Author(s):  
Manfred Heinlein ◽  
Hal S. Padgett ◽  
J. Scott Gens ◽  
Barbara G. Pickard ◽  
Steven J. Casper ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Tobacco Mosaic Virus ◽  
Mosaic Virus ◽  
Movement Protein ◽  
Virus Movement ◽  
Changing Patterns

scholarly journals Tobacco mosaic virus and the study of early events in virus infections

1999 ◽  
Vol 354 (1383) ◽  
pp. 603-611 ◽  
Author(s):  
John G. Shaw
Keyword(s):  
Tobacco Mosaic Virus ◽  
Mosaic Virus ◽  
Host Cells ◽  
Progeny Virus ◽  
Virus Infections ◽  
Relevant Research ◽  
Protein Subunits ◽  
Virus Particles ◽  
Initial Interaction ◽  
Positive Strand Rna

In order to establish infections, viruses must be delivered to the cells of potential hosts and must then engage in activities that enable their genomes to be expressed and replicated. With most viruses, the events that precede the onset of production of progeny virus particles are referred to as the early events and, in the case of positive–strand RNA viruses, they include the initial interaction with, and the entry of, host cells and the release (uncoating) of the genome from the virus particles. Though the early events remain one of the more poorly understood areas of plant virology, the virus with which most of the relevant research has been performed is tobacco mosaic virus (TMV). In spite of this effort, there remains much uncertainty about the form or constituent of the virus that actually enters the initially invaded cell in a plant and about the mechanism(s) that trigger the subsequent uncoating (virion disassembly) reactions. A variety of approaches have been used in attempts to determine the fate of TMV particles that are involved in the establishment of an infection and these are briefly described in this review. In some recent work, it has been proposed that the uncoating process involves the bidirectional release of coat protein subunits from the viral RNA and that these activities may be mediated by cotranslational and coreplicational disassembly mechanisms.

scholarly journals Beijerinck's work on tobacco mosaic virus: historical context and legacy

1999 ◽  
Vol 354 (1383) ◽  
pp. 675-685 ◽  
Author(s):  
L. Bos
Keyword(s):  
Molecular Biology ◽  
Tobacco Mosaic Virus ◽  
Mosaic Virus ◽  
Close Association ◽  
Historical Context ◽  
True Nature ◽  
Animal Virus ◽  
Virus Particles ◽  
Contagious Diseases ◽  
History Of

Beijerinck's entirely new concept, launched in 1898, of a filterable contagium vivum fluidum which multiplied in close association with the host's metabolism and was distributed in phloem vessels together with plant nutrients, did not match the then prevailing bacteriological germ theory. At the time, tools and concepts to handle such a new kind of agent (the viruses) were non–existent. Beijerinck's novel idea, therefore, did not revolutionize biological science or immediately alter human understanding of contagious diseases. That is how bacteriological dogma persisted, as voiced by Loeffler and Frosch when showing the filterability of an animal virus (1898), and especially by Ivanovsky who had already in 1892 detected filterability of the agent of tobacco mosaic but kept looking for a microbe and finally (1903) claimed its multiplication in an artificial medium. The dogma was also strongly advocated by Roux in 1903, when writing the first review on viruses, which he named ‘so–called “invisible” microbes’, unwittingly including the agent of bovine pleuropneumonia, only much later proved to be caused by a mycoplasma. In 1904, Baur was the first to advocate strongly the chemical view of viruses. But uncertainty about the true nature of viruses, with their similarities to enzymes and genes, continued until the 1930s when at long last tobacco mosaic virus particles were isolated as an enzyme–like protein (1935), soon to be better characterized as a nucleoprotein (1937). Physicochemical virus studies were a key element in triggering molecular biology which was to provide further means to reveal the true nature of viruses ‘at the threshold of life’. Beijerinck's 1898 vision was not appreciated or verified during his lifetime. But Beijerinck already had a clear notion of the mechanism behind the phenomena he observed. Developments in virology and molecular biology since 1935 indicate how close Beijerinck (and even Mayer, Beijerinck's predecessor in research on tobacco mosaic) had been to the mark. The history of research on tobacco mosaic and the commitments of Mayer, Beijerinck and others demonstrate that progress in science is not only a matter of mere technology but of philosophy as well. Raemaekers' Mayer cartoon, inspired by Beijerinck, artistically represents the crucial question about the reliability of our images of reality, and about the scope of our technological interference with nature.

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