Poliovirus metabolism and the cytoskeletal framework: detergent extraction and resinless 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.

Download Full-text

Normal Synaptonemal Complex and Abnormal Recombination Nodules in Two Alleles of the Drosophila Meiotic Mutant mei-W68

Genetics ◽

10.1093/genetics/163.4.1337 ◽

2003 ◽

Vol 163 (4) ◽

pp. 1337-1356 ◽

Cited By ~ 3

Author(s):

Adelaide T C Carpenter

Keyword(s):

Electron Microscopy ◽

Synaptonemal Complex ◽

High Frequency ◽

Serial Section ◽

The Other ◽

Wild Type ◽

Recombination Nodules ◽

Section Electron ◽

Serial Section Electron Microscopy ◽

Section Electron Microscopy

Abstract The meiotic phenotypes of two mutant alleles of the mei-W68 gene, 1 and L1, were studied by genetics and by serial-section electron microscopy. Despite no or reduced exchange, both mutant alleles have normal synaptonemal complex. However, neither has any early recombination nodules; instead, both exhibit high numbers of very long (up to 2 μm) structures here named “noodles.” These are hypothesized to be formed by the unchecked extension of identical but much shorter structures ephemerally seen in wild type, which may be precursors of early recombination nodules. Although the mei-W68L1 allele is identical to the mei-W681 allele in both the absence of early recombination nodules and a high frequency of noodles (i.e., it is amorphic for the noodle phene), it is hypomorphic in its effects on exchange and late recombination nodules. The differential effects of this allele on early and late recombination nodules are consistent with the hypothesis that Drosophila females have two separate recombination pathways—one for simple gene conversion, the other for exchange.

Download Full-text

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.

Download Full-text

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.

Download Full-text

Germanium Incorporation in Silicon Carbide Epitaxial Layers Using Molecular Beam Epitaxy on 4H-SiC Substrates

Materials Science Forum ◽

10.4028/www.scientific.net/msf.963.127 ◽

2019 ◽

Vol 963 ◽

pp. 127-130

Author(s):

Jörg Pezoldt ◽

Charbel Zgheib ◽

Thomas Stauden ◽

Gernot Ecke ◽

Thomas Kups ◽

...

Keyword(s):

Electron Microscopy ◽

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Atomic Layer ◽

Solubility Limit ◽

Solid Solubility Limit ◽

Transmission Electron ◽

Section Electron ◽

Heteroepitaxial Layers ◽

Section Electron Microscopy

Ternary (Si1-xCy)Gex+y solid solutions were grown on Si-face 4H-SiC applying atomic layer molecular beam epitaxy at low temperatures. The grown layers consist of twinned 3C-SiC revealed by cross section electron microscopy. The germanium was incorporated on silicon lattice sites as revealed by atomic location by channeling enhanced microanalysis transmission electron microscopy studies. The Ge concentration of the grown 3C-(Si1-xCy)Gex+y heteroepitaxial layers decreases with increasing growth temperatures, but exceeds the solid solubility limit.

Download Full-text

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.

Download Full-text