Quick-Freeze, Deep-Etch Electron Microscopy Reveals the Characteristic Architecture of the Fission Yeast Spore

The spore of the fission yeast Schizosaccharomyces pombe is a dormant cell that is resistant to a variety of environmental stresses. The S. pombe spore is coated by a proteinaceous surface layer, termed the Isp3 layer because it comprises mainly Isp3 protein. Although thin-section electron microscopy and scanning electron microscopy have revealed the fundamental structure of the spore, its architecture remains unclear. Here we visualized S. pombe spores by using a quick-freeze replica electron microscopy (QFDE-EM) at nanometer resolution, which revealed novel characteristic structures. QFDE-EM revealed that the Isp3 layer exists as an interwoven fibrillar layer. On the spore cell membrane, many deep invaginations, which are longer than those on the vegetative cell membrane, are aligned in parallel. We also observed that during spore germination, the cell surface changes from a smooth to a dendritic filamentous structure, the latter being characteristic of vegetative cells. These findings provide significant insight into not only the structural composition of the spore, but also the mechanism underlying the stress response of the cell.

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Binding of Tetrahymena dynein to axonemes of Marsilea vestita lacking the outer dynein arm

Journal of Cell Science ◽

10.1242/jcs.73.1.299 ◽

1985 ◽

Vol 73 (1) ◽

pp. 299-310

Author(s):

J.S. Hyams

Keyword(s):

Electron Microscopy ◽

Polyacrylamide Gel Electrophoresis ◽

Valuable Insight ◽

Marsilea Vestita ◽

Thin Section Electron Microscopy ◽

Section Electron ◽

And Function ◽

Relationship Of ◽

The Relationship ◽

Insight Into

Axonemes from the heterosporous water fern Marsilea vestita were fixed in the presence of tannic acid and examined by thin-section electron microscopy. Transverse sections revealed the normal 9+2 configuration except for the absence of the outer of the two dynein arms. Both arms were normally preserved in parallel preparations of Chlamydomonas axonemes. Isolated dynein from the ciliated protozoon Tetrahymena bound to Marsilea axonemes at the site normally occupied by the outer arm. Dynein binding was partially reversed by ATP as judged by both electron microscopy and polyacrylamide gel electrophoresis. This system should provide a valuable insight into the biochemistry and function of the inner dynein arm and the relationship of the two arms to motility in more conventionally equipped axonemes.

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The Infection of Cells by Bullet-Shaped Viruses

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100063779 ◽

1969 ◽

Vol 27 ◽

pp. 372-373

Author(s):

Frederick A. Murphy ◽

Alyne K. Harrison ◽

Sylvia G. Whitfield

Keyword(s):

Electron Microscopy ◽

Physical Properties ◽

Host Cell ◽

Thin Section ◽

Cultured Cells ◽

Cell Infection ◽

Thin Section Electron Microscopy ◽

Section Electron ◽

Section Electron Microscopy

The bullet-shaped viruses are currently classified together on the basis of similarities in virion morphology and physical properties. Biologically and ecologically the member viruses are extremely diverse. In searching for further bases for making comparisons of these agents, the nature of host cell infection, both in vivo and in cultured cells, has been explored by thin-section electron microscopy.

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Effect of taxol on the interaction of tubulin with myosin filaments

Canadian Journal of Biochemistry and Cell Biology ◽

10.1139/o84-112 ◽

1984 ◽

Vol 62 (9) ◽

pp. 878-884 ◽

Cited By ~ 6

Author(s):

Toshihiro Fujii ◽

Tatsuo Suzuki ◽

Akira Hachimori ◽

Michiyo Fujii ◽

Yoshiyuki Kondo ◽

...

Keyword(s):

Electron Microscopy ◽

Skeletal Muscle ◽

Atpase Activity ◽

Cross Section ◽

Molar Ratio ◽

Tubulin Polymerization ◽

Myosin Filaments ◽

Thin Section Electron Microscopy ◽

Section Electron ◽

Section Electron Microscopy

The interaction between polymerized tubulin from porcine brain and myosin from rabbit skeletal muscle was examined. The addition of myosin to the solution of tubulin polymerized by taxol resulted in a remarkable increase in turbidity within a few minutes at 37 °C, and a dense and stable precipitate was formed. The maximal molar ratio of tubulin bound to myosin was calculated to be about 4, while the value was about 2 when 6S tubulin was used. Both podophyllotoxin and colchicine suppressed the taxol-dependent increase of the binding of tubulin to myosin, but only when they were preincubated with tubulin prior to addition of taxol. 6S tubulin inhibited with aetin-activated Mg2+-ATPase activity of myosin, and polymerized tubulin inhibited the Mg-ATPase more than 6S tubulin. Dense precipitates of tubulin and myosin were observed by thin-section electron microscopy. Microtubules were observed to be entangled in myosin filaments and single microtubules were occasionally surrounded by five myosin filaments in a cross section, similar to actin–myosin arrays in muscle. After incubation of tubulin with myosin, taxol was able to induce tubulin polymerization in the same way as it polymerized microtubules in the absence of myosin.

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STUDIES OF THE ULTRASTRUCTURE AND RIBOSOMAL ARRANGEMENTS OF THE PLEUROPNEUMONIA-LIKE ORGANISM A5969

The Journal of Cell Biology ◽

10.1083/jcb.25.1.139 ◽

1965 ◽

Vol 25 (1) ◽

pp. 139-150 ◽

Cited By ~ 30

Author(s):

Jack Maniloff ◽

Harold J. Morowitz ◽

Russell J. Barrnett

Keyword(s):

Electron Microscopy ◽

Plasma Membrane ◽

Chemical Analysis ◽

Thin Section ◽

Differential Centrifugation ◽

Thin Section Electron Microscopy ◽

Section Electron ◽

Section Electron Microscopy ◽

Cellular Organelles

Thin-section electron microscopy, together with isolation of cellular organelles by differential centrifugation and chemical analysis, has been used to investigate the ultrastructure of the avian pleuropneumonia-like organism A5969. Each cell (approximate diameter 5500 A) was surrounded by a 150 A plasma membrane. In the center of the cell was an unbounded area, granular in appearance and containing the cell's DNA. The periphery of the cell contained granules of several different sizes and densities. The most dense particles (150 A) corresponded to the 78S ribosomes. These particles exhibited two predominant arrangements: (a) sometimes they showed cubic packing; (b) most arrays, however, were consistent with cylindrical arrangements of approximately 50 particles. Bundles of up to 18 arrays were observed. Structured blebs have been found protruding from the surface of log phase cells.

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Mycoplasma-like organisms as causal agents of potato purple top wilt in Queensland

Australian Journal of Agricultural Research ◽

10.1071/ar9850443 ◽

1985 ◽

Vol 36 (3) ◽

pp. 443 ◽

Cited By ~ 12

Author(s):

RM Harding ◽

DS Teakle

Keyword(s):

Electron Microscopy ◽

Thin Section ◽

Strong Evidence ◽

Tomato Plant ◽

Tomato Plants ◽

Potato Plants ◽

Thin Section Electron Microscopy ◽

Section Electron ◽

Potato Purple Top ◽

Section Electron Microscopy

The eggplant little-leaf agent was graft transmitted to tomato causing big-bud symptoms. Transmission from the big-bud tomato to potato by grafting or the leafhopper Orosius argentatus resulted in the development of purple top wilt symptoms. Thin-section electron microscopy revealed mycoplasma-like organisms present in the phloem sieve elements of a big-bud tomato plant and purple top wilt potato plants infected by grafting or leafhoppers. When tubers from graft-infected potato plants were planted, 73% produced spindly shoots and 44% of these later developed purple top wilt symptoms. When scions from either field-infected or experimentally infected potato plants showing purple top wilt symptoms were grafted onto tomato plants, 24% and 62% respectively developed big-bud symptoms. The results provide strong evidence for the mycoplasmal aetiology of some, if not all, potato purple top wilt in Queensland.

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Ebola Virus Hemorrhagic Fever, Zaire, 1995: an Ultrastructural Study

Microscopy and Microanalysis ◽

10.1017/s1431927600007273 ◽

1997 ◽

Vol 3 (S2) ◽

pp. 77-78

Author(s):

C. S. Goldsmith ◽

P. E. Rollin ◽

X. H. Zhang ◽

C. J. Peters ◽

S. R. Zaki

Keyword(s):

Electron Microscopy ◽

Ebola Virus ◽

Hemorrhagic Fever ◽

Ultrastructural Studies ◽

The Family ◽

Thin Section Electron Microscopy ◽

Section Electron ◽

Autopsy Tissues ◽

Gamma Irradiated ◽

Tissue Specimens

Ebola and Marburg viruses, members of the family Filoviridae, cause a severe and often fatal hemorrhagic fever. In April and May of 1995, an outbreak of Ebola virus hemorrhagic fever occurred in Kikwit, Zaire, and of 318 known cases, approximately 77% died. The ultrastructural pathology associated with filoviruses has been well described in non-human primates. On the other hand, ultrastructural studies on human tissues have been relatively few, and limited for the most part to examination of the liver. We report here our ultrastructural observations of autopsy tissues from the liver, as well as lung, skin, and testes of infected patients by using both thin section electron microscopy (EM) and immunogold labeling electron microscopy (IEM).At the hospital in Kikwit, strict barrier precautions were employed to collect tissue specimens. These were diced into small blocks, placed into fixative, and later transferred to phosphate buffer. Specimens were hand-transported to the CDC in Atlanta, gamma-irradiated, and embedded in either Epon-substitute/Araldite for standard EM, or in LR White for IEM.

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