Blue Light Inhibits Mitosis in Tissue Culture Cells

1998 ◽  
Vol 18 (4) ◽  
pp. 215-224 ◽  
Author(s):  
L. A. Gorgidze ◽  
S. A. Oshemkova ◽  
I. A. Vorobjev
Keyword(s):  
Tissue Culture ◽  
Blue Light ◽  
Uv Light ◽  
Green Light ◽  
Light Wavelength ◽  
Culture Cells ◽  
Anaphase Onset ◽  
Biological Responses ◽  
Embryo Cells ◽  
Cell Adsorption

Irradiation of the mitotic (prophase and prometaphase) tissue culture PK (pig kidney embryo) cells using mercury arc lamp and band-pass filters postponed or inhibited anaphase onset. The biological responses observed after irradiation were: (i) normal cell division, (ii) delay in metaphase and then normal anaphase and incomplete cytokinesis, (iii) exit into interphase without separation of chromosomes, (iv) complete mitotic blockage. Cell sensitivity to the light at wavelengths from 423 and 488 nm was nearly the same; to the near UV light (wavelength 360 nm) it was 5–10 times more; to the green light (wavelength >500 nm) it was at least 10 times less. To elucidate the possible mechanism of the action of blue light we measured cell adsorption and examined cell autofluorescence. Autofluorescence of cytoplasmic granules was exited at wavelengths of 450–490 nm, but not at >500 nm. In mitotic cells fluorescent granules accumulated around the spindle. We suppose blue light irradiation induces formation of the free radicals and/or peroxide, and thus perturb the checkpoint system responsible for anaphase onset.

scholarly journals Localization of Mad2 to Kinetochores Depends on Microtubule Attachment, Not Tension

1998 ◽  
Vol 141 (5) ◽  
pp. 1181-1191 ◽  
Author(s):  
Jennifer C. Waters ◽  
Rey-Huei Chen ◽  
Andrew W. Murray ◽  
E.D. Salmon
Keyword(s):  
Tissue Culture ◽  
Binding Sites ◽  
Culture Cells ◽  
Microtubule Attachment ◽  
Anaphase Onset ◽  
Tissue Culture Cells ◽  
Cell Biol ◽  
Multiple Binding Sites ◽  
Multiple Binding ◽  
Spindle Microtubules

A single unattached kinetochore can delay anaphase onset in mitotic tissue culture cells (Rieder, C.L., A. Schultz, R. Cole, G. Sluder. 1994. J. Cell Biol. 127:1301–1310). Kinetochores in vertebrate cells contain multiple binding sites, and tension is generated at kinetochores after attachment to the plus ends of spindle microtubules. Checkpoint component Mad2 localizes selectively to unattached kinetochores (Chen, R.-H., J.C. Waters, E.D. Salmon, and A.W. Murray. 1996. Science. 274:242–246; Li, Y., and R. Benezra. Science. 274: 246–248) and disappears from kinetochores by late metaphase, when chromosomes are properly attached to the spindle. Here we show that Mad2 is lost from PtK1 cell kinetochores as they accumulate microtubules and re-binds previously attached kinetochores after microtubules are depolymerized with nocodazole. We also show that when kinetochore microtubules in metaphase cells are stabilized with taxol, tension at kinetochores is lost. The phosphoepitope 3f3/2, which has been shown to become dephosphorylated in response to tension at the kinetochore (Nicklas, R.B., S.C. Ward, and G.J. Gorbsky. 1995. J. Cell Biol. 130:929–939), is phosphorylated on all 22 kinetochores after tension is reduced with taxol. In contrast, Mad2 only localized to an average of 2.6 out of the 22 kinetochores in taxol-treated PtK1 cells. Therefore, loss of tension at kinetochores occupied by microtubules is insufficient to induce Mad2 to accumulate on kinetochores, whereas unattached kinetochores consistently bind Mad2. We also found that microinjecting antibodies against Mad2 caused cells arrested with taxol to exit mitosis after ∼12 min, while uninjected cells remained in mitosis for at least 6 h, demonstrating that Mad2 is necessary for maintenance of the taxol-induced mitotic arrest. We conclude that kinetochore microtubule attachment stops the Mad2 interactions at kinetochores which are important for inhibiting anaphase onset.

scholarly journals Neurite regrowth stimulation by a red-light spot focused on the neuronal cell soma following blue light-induced retraction

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Yu-Chiu Kao ◽  
Yu-Cing Liao ◽  
Pei-Lin Cheng ◽  
Chau-Hwang Lee
Keyword(s):  
Blue Light ◽  
Power Level ◽  
Red Light ◽  
Green Light ◽  
Neuronal Cell ◽  
Neurite Growth ◽  
Biological Tissues ◽  
Light Spot ◽  
Light Illumination ◽  
Light Wavelength

AbstractThe interaction of light with biological tissues has been considered for various therapeutic applications. Light-induced neurite growth has the potential to be a clinically useful technique for neuron repair. However, most previous studies used either a large illumination area to accelerate overall neurite growth or employed a light spot to guide a growing neurite. It is not clear if optical stimulation can induce the regrowth of a retracted neurite. In the present work, we used blue light (wavelength: 473 nm) to cause neurite retraction, and we proved that using a red-light (wavelength: 650 nm) spot to illuminate the soma near the junction of the retracted neurite could induce neurite regrowth. As a comparison, we found that green light (wavelength 550 nm) had a 62% probability of inducing neurite regrowth, while red light had a 75% probability of inducing neurite regrowth at the same power level. Furthermore, the neurite regrowth length induced by red light was increased by the pre-treatment with inhibitors of myosin functions. We also observed actin propagation from the soma to the tip of the re-growing neurite following red-light stimulation of the soma. The red light-induced extension and regrowth were abrogated in the calcium-free medium. These results suggest that illumination with a red-light spot on the soma may trigger the regrowth of a neurite after the retraction caused by blue-light illumination.

scholarly journals Efek Panjang Gelombang Terhadap Pertumbuhan Propagul Pada Kultur Jaringan Eucheuma cottonii Doty, 1885 (Rhodophyceae; Solieracea)

2020 ◽  
Vol 23 (3) ◽  
pp. 349-356
Author(s):  
Wilis Ari Setyati ◽  
Rini Pramesti ◽  
Delianis Pringgenies ◽  
Chrisna Adhi Suryono ◽  
Irwani Irwani ◽  
...  
Keyword(s):  
Tissue Culture ◽  
Blue Light ◽  
Specific Growth ◽  
Red Light ◽  
Light Treatment ◽  
Fluorescent Light ◽  
Limiting Factor ◽  
Light Wavelength ◽  
Eucheuma Cottonii ◽  
Branching Index

The problem in cultivating Eucheuma cottonii is the procurement of seeds and techniques currently developed through tissue culture. The limiting factor in this technique is the use of optimal light for the growth of the seaweed. The aims of study was to optimize the wavelength of light on the growth of E cottonii propagules. The research method is laboratory experimental with the treatment of different wavelengths of light: red light wavelength (λ = 633.8 nm), green (λ = 515.8 nm), blue (λ = 455.7 nm), combined light on the lamp LED (λ = 456.6 nm, 515.8 nm and 632.9 nm), and fluorescent light in TL lamps (λ = 407 nm, 443 nm, 557 nm and 592 nm). The results showed that the wavelength had a significant effect (p ≤0.05) on the growth of E cottonii. The best treatment for blue light with absolute, relative and specific growth values of propagule weight of 155 ± 11.910 mg, 419 ± 70.849%, and 5.860 ± 0.501% / day. The absolute, relative and specific growth values for propagule diameter were 701 ± 123.1 mm, 63 ± 12% and 1.73 ± 0.27% / day. The percentage of branching growth and the branching index were 60.85 ± 9.16% and 27.77 ± 1.23. Blue light treatment is optimal radiation in the E. cottonii tissue culture  Permasalahan dalam budidaya Eucheuma cottonii adalah pengadaan bibit dan teknik yang berkembang saat ini melalui kultur jaringan. Faktor pembatas dalam teknik ini adalah penggunaan cahaya yang optimal untuk pertumbuhan rumput laut. Penelitian bertujuan untuk melakukan optimasi panjang gelombang cahaya terhadap pertumbuhan propagul E cottonii. Metode penelitian secara experimental laboratoris dengan perlakuan perbedaan panjang gelombang cahaya : panjang gelombang lampu cahaya merah (λ = 633,8 nm), hijau (λ = 515,8 nm), biru (λ = 455,7 nm), cahaya gabungan pada lampu LED (λ = 456,6 nm, 515,8 nm dan 632,9 nm), dan cahaya flourescent pada lampu TL (λ = 407 nm, 443 nm, 557 nm dan 592 nm). Hasil penelitian menunjukkan bahwa panjang gelombang berpengaruh signifikan (p < 0,05) terhadap pertumbuhan E cottonii. Perlakuan terbaik pada cahaya biru dengan nilai pertumbuhan mutlak, relatif dan spesifik bobot propagul sebesar 155±11,910 mg, 419 ± 70,849 %, dan 5,860 ± 0,501 %/hari. Nilai pertumbuhan mutlak, relatif dan spesifik diameter propagul sebesar 701±123,1 mm, 63±12 % dan 1,73±0,27 %/hari. Persentase pertumbuhan percabangan dan indeks percabangan sebesar 60,85±9,16 % dan  27,77±1,23. Perlakuan sinar biru merupakan penyinaran optimal dalam kultur jaringan E. cottonii.

Cytoplasmic Tubules in Cells Infected with Laryngotracheitis Virus

1969 ◽  
Vol 27 ◽  
pp. 376-377
Author(s):  
A. M. Watrach
Keyword(s):  
Tissue Culture ◽  
Small Proportion ◽  
Chicken Embryo ◽  
Culture Cells ◽  
Tissue Culture Cells ◽  
Morphologic Characteristics ◽  
Infectious Laryngotracheitis ◽  
Laryngotracheitis Virus ◽  
In Cells

During a study of the development of infectious laryngotracheitis (LT) virus in tissue culture cells, unusual tubular formations were found in the cytoplasm of a small proportion of the affected cells. It is the purpose of this report to describe the morphologic characteristics of the tubules and to discuss their possible association with the development of virus.The source and maintenance of the strain of LT virus have been described. Prior to this study, the virus was passed several times in chicken embryo kidney (CEK) tissue culture cells.

A Method for Electron Microscopic Study of Tissue Culture Cell Monolayers Grown in Tubes

1967 ◽  
Vol 25 ◽  
pp. 132-133
Author(s):  
R. Stephens ◽  
G. Schidlovsky ◽  
S. Kuzmic ◽  
P. Gaudreau
Keyword(s):  
Electron Microscopy ◽  
Tissue Culture ◽  
Light Microscopy ◽  
Cell Sheet ◽  
Culture Cell ◽  
Tissue Culture Cell ◽  
Electron Microscopic ◽  
Cell Sheets ◽  
Morphological Alterations ◽  
Culture Cells

The usual method of scraping or trypsinization to detach tissue culture cell sheets from their glass substrate for further pelletization and processing for electron microscopy introduces objectionable morphological alterations. It is also impossible under these conditions to study a particular area or individual cell which have been preselected by light microscopy in the living state.Several schemes which obviate centrifugation and allow the embedding of nondetached tissue culture cells have been proposed. However, they all preserve only a small part of the cell sheet and make use of inverted gelatin capsules which are in this case difficult to handle.We have evolved and used over a period of several years a technique which allows the embedding of a complete cell sheet growing at the inner surface of a tissue culture roller tube. Observation of the same cell by light microscopy in the living and embedded states followed by electron microscopy is performed conveniently.

The Fine Structure of Replicating Simian Adenoviruses in LLC-MK2

1968 ◽  
Vol 26 ◽  
pp. 220-221
Author(s):  
Matias Pardo ◽  
Malcolm Slifkin ◽  
Leonard Merkow ◽  
Marie Sanchez
Keyword(s):  
Tissue Culture ◽  
Post Infection ◽  
Cesium Chloride ◽  
Longitudinal Section ◽  
Tubular Structures ◽  
Virus Particles ◽  
Ultrastructural Studies ◽  
Culture Cells ◽  
Simian Adenovirus ◽  
Infectivity Titer

The simian adenoviruses SV20, SV30 and SA7 have been found to be oncogenic in the Syrian hamster. The growth characteristics and replicative cycle of these viruses in tissue culture therefore appeared appropriate to investigate. Cesium chloride purified simian adenovirus with an infectivity titer of 100 TCID50, was inoculated into monolayers of LLC-MK2 cells. Cells were fixed in osmium tetroxide and embedded for ultrastructural studies at 1, 3, 6, 9, 18, 24, 48, 72, 120 and 192 hours post-infection.At the first hour post-infection, virus particles were adsorbed to the plasmalemma and found within the peripheral cytoplasm of many LLC-MK2 cells (Fig. 1). Although the first detection of infectious virus occurred at 14 hours and infectivity titers did not reach a maximum until 30 hours, intranuclear virus particles were observed by 3 hours in typical adenovirus crystalline array (Fig. 2) by means of electron microscopy. These typical honeycomb arrayed virus particles at 3 hours provided evidence of significant replication in approximately 5 percent of tissue culture cells examined. Simultaneously, a classical nuclear inclusion manifested by peripheral condensation of nuclear chromatin was evident by light microscopy. As early at 6 to 9 hours, unusual intranuclear concentric membranes formed “tubes” which contained linear arranged virus particles (Fig. 3). In transverse or tangential sections, these “tubes” appeared cochlear-like in shape. In longitudinal section, these intranuclear tubular structures contained individual virus particles at various stages of maturation in a linear arranged order. This arrangement resembled “peas in a pod”.

Application of EM to differentiate herpes virus from pox virus in genital specimens

1994 ◽  
Vol 52 ◽  
pp. 262-263
Author(s):  
K. Rekrut ◽  
K. Schleuter
Keyword(s):  
Tissue Culture ◽  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Fresh Tissue ◽  
Culture Cells ◽  
Viral Transport ◽  
Carbon Coated ◽  
Immuno Assay ◽  
Simplex Virus ◽  
Enzyme Immuno Assay

Confirmation of herpes simplex virus (HSV) from genital lesions of obstetrical (OB) patients may affect both the management of the delivery and of the neonate.(l,2) During 1992 and 1993, 4,450 genital specimens from OB patients were submitted in viral transport media for herpes culture. The specimens were inoculated into MRC-5, Vero, and A-549 tissue culture tubes, incubated, and examined daily for 7 days for cytopathic effect (CPE). The original specimens were frozen at −70° C until final reports were issued. Culture tubes with CPE were tested by the Dupont Herpchek enzyme immuno assay (EIA) to confirm the presence of herpes simplex virus (HSV). (3,4) 170 OB patient specimens were positive by culture and confirmed by EIA.There were also 63 cultures exhibiting CPE ressembling HSV which were negative by EIA testing, which failed to pass in fresh tissue culture cells or progress to more enhanced CPE in culture. These original specimens were screened by electron microscopy after direct ultracentrifugation employing the Beckman airfuge with the EM 90 rotor on to formvar carbon-coated 300 mesh copper grids and negatively stained with 2% PTA.

Sulfhydryl bond formation is a prerequisite for proper cycling of centrosomes and chromosomes in mammalian tissue culture cells

1993 ◽  
Vol 51 ◽  
pp. 342-343
Author(s):  
Heide Schatten ◽  
Neidhard Paweletz ◽  
Ron Balczon
Keyword(s):  
Tissue Culture ◽  
Cell Cycle Progression ◽  
Group Formation ◽  
Sulfhydryl Group ◽  
Mammalian Tissue ◽  
Mitotic Chromosomes ◽  
Microtubule Network ◽  
Culture Cells ◽  
Tissue Culture Cells ◽  
Transmission Electron

To study the role of sulfhydryl group formation during cell cycle progression, mammalian tissue culture cells (PTK2) were exposed to 100¼M 2-mercaptoethanol for 2 to 6 h during their exponential phase of growth. The effects of 2-mercaptoethanol on centrosomes, chromosomes, microtubules, membranes and intermediate filaments were analyzed by transmission electron microscopy (TEM) and by immunofluorescence microscopy (IFM) methods using a human autoimmune antibody directed against centrosomes (SPJ), and a mouse monoclonal antibody directed against tubulin (E7). Chromosomes were affected most by this treatment: premature chromosome condensation was detected in interphase nuclei, and the structure in mitotic chromosomes was altered compared to control cells. This would support previous findings in dividing sea urchin cells in which chromosomes are arrested at metaphase while the centrosome splitting cycle continues. It might also support findings that certairt-sulfhydryl-blocking agents block cyclin destruction. The organization of the microtubule network was scattered probably due to a looser organization of centrosomal material at the interphase centers and at the mitotic poles.

UDP-D-glucose 4-epimerase activity of the tissue culture of white poplars (Populus alba L. var. pyramidalis)

1982 ◽  
Vol 47 (5) ◽  
pp. 1530-1536 ◽  
Author(s):  
Ladislav Bilisics ◽  
Štefan Karácsonyi ◽  
Marta Kubačková
Keyword(s):  
Tissue Culture ◽  
Cell Walls ◽  
Enzyme Preparation ◽  
Uridine Diphosphate ◽  
Populus Alba ◽  
Activity Change ◽  
White Poplar ◽  
Culture Cells ◽  
Tissue Culture Cells ◽  
Galactose Content

The presence of UDP-D-glucose 4-epimerase (EC 5.1.3.2) in the culture tissue of white poplar was evidenced. As found, the partially purified enzyme preparation contained UDP-D-glucose glucosyltransferase, UDP-D-galactose galactosyltransferase and non-specific enzymes able to cleave the uridine-diphosphate saccharides into the appropriate hexose monophosphates. The activity change of UDP-D-glucose 4-epimerase in tissue culture cells during the growth was in accord with changes in D-galactose content in cell walls and indicated the possibility to regulate the formation of polysaccharides containing D-galactose at the level of production of UDP-D-galactose in cells.

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