• Applied Biological Chemistry
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• v.35 no.6
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• pp.507-512
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• 1992

A ${\beta}-1,3-glucanase$ of soybean (Glycine max) was isolated, and the effects of benzyladenine(BA) on celluar levels of the enzyme content and activity were studied. The effects of BA on callose content in cell wall and wall regeneration of protoplasts were also studied to show promoting effect of cytokinin in cell wall regeneration and to elucidate action mode of cytokinin. The polypeptide of 21 kD was identified as ${\beta}-1,3-glucanase$, and the cellular content and activity of this polypeptide were decreased by BA treatment. The callose content in cell wall of callus and the wall regeneration of protoplasts were increased by BA treatment. These results indicate that cytokinin promotes cell wall regeneration by inhibition of callose degradation via decreasing ${\beta}-1,3-glucanase$ level in cell.

• Korean Journal of Microbiology
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• v.23 no.3
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• pp.190-196
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• 1985

For frequency improvement of protoplast fusion in Brevibacterium flavum, Brevibacterium lactofermentum lactofermentum and Corynebacterium glutamicum, the effect of plasma expanders on fusion and cell wall regeneration, compatison between direct and two-step selection method, tendency of fusion frequency according to pH of fusion fluid and polyethylene glycol concentration were examined. By addition of 3% polyvinyl pyrrolidone to cell wall regeneration medium, regeneration frequencies were expressed 23 (Brevibacterium lactofermentum), 10.4 (Brevibacterium flavum) and 2.7 (Corynebacterium glutamicum) times higher than those of none polyvinyl pyrrolidone medium respectively.

• Journal of Plant Biology
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• v.31 no.2
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• pp.121-130
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• 1988

In order to clarify effects of phytohormones on the viability and the cell wall regeneration of protoplasts isolated from Nicotiana tobacum L. var. BY4, protoplasts isolated from mesophyll tissue were cultured on the Murashige-Skoog liquid media supplemented with auxin(2, 4-D, NAA, IAA) and/or cytokinin (kinetin, BAP, 2ip). Viability of protopplasts was higher in the culture medium containing auxin and cytokinin, especially in the combination of 2, 4-D and BAP. The effectual cell wall regeneration of protolasts was observed when theprotoplasts were cultrued on the medium supplemented with auxin alone, especially with IAA. Cell wall regernation started from 2-3 days after culture and was not detected at budding regions. When the protoplasts were cultured on the phytohormone-free medium, the viability of protoplasts dramatically decreased 4 days after culture.

• Applied Biological Chemistry
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• v.30 no.4
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• pp.300-304
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• 1987

Effects of benzyladenine (BA) on viability, cell wall regeneration and division of soybean (Glycine max, Var. Acme) protoplasts isolated from suspension cells of cotyledonary callus were investigated. The uptake of BA by the protoplasts was also studied. BA increased protoplast viability, and promoted cell wall regeneration and cell division. The level of BA in protoplasts was increased to a maximum at about 20 hour incubation and 2/3 of the total amount of BA accumulated in protoplast was absorbed within 6 hours.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.4
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• pp.68-76
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• 2006

The minimization of maximum DPF wall temperature and the fast Light-off during regeneration are the targets for the high durability of the DPF system and the high efficiency of regeneration. In order to predict transient thermal response of DPF, one-channel numerical modeling has been adopted. The effect of the ratio of length to diameter(L/D), cell density, the amount of soot loading on temporal thermal response and regeneration characteristics has been numerically investigated under two different running conditions: city driving mode and high speed mode. The results indicate that the maximum wall temperature of DPF increase with increasing 'L/D' in 'High speed mode'. For 'City driving mode', the maximum wall temperature decreases with increasing 'L/D' in the range of $'L/D{\geq}0.6'$. The maximum temperature decreases with increasing cell density because heat conduction and heat capacity are increased. It is also found that the effect of amount of soot loading on light-off time is negligible.

• Journal of Plant Biology
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• v.32 no.4
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• pp.215-226
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• 1989

The effects of Ca2+ on polyamines on callose contents of carrot suspension cultured cells were studied. The regeneration process of the cell wall of carrot protoplast observed through the electron microscope. Treatment of the carrot suspension cultured cells with Ca2+ and polyamines resulted in considerable increase on callose contents at 0.1 mM of Ca2+ and polyamines, particulary spermidine. Poly-L-lysine and poly-L-ornithine increased about 30% and 100% of callose contents than that of the control respectively, whereas verapamil and flunarizine markedly decreased the callose contents. These effects of Ca2+ of free ion rather than as Ca2+-calmodulin complex. During the cultivation of the protoplast, the regeneration of the cell wall was somewhat observed on the 4th day, however, it was inhibited by verapamil. These results suggested that the promotive action of Ca2+ and polyamines were manifested in the callose contents and the regeneraton of the cell wall.

• Applied Microscopy
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• v.13 no.1
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• pp.49-61
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• 1983

Protoplast releasing mechanisms from Trichoderma koningii, fine structures of the released protoplsts, and their regeneration mode were studied by scanning and transmission electron microscopy. Two types of protoplast releasing mechanisms were observed. In one mechanism, cytoplasm emerged through a cell wall pore developed by cell lytic enzymes and formed a spherical protoplast. In the other mechanism, as the cell wall became progressively thinner, the inner cytoplasm partially rounded to form nonspherical bodies which became spherical protoplasts after being released into the enzyme solution. But, these two types of protoplast releasing mechanisms did not seem to be. mutually exclusive but could occur on the same mycelium simultaneously. And it appeared that cytoplasm which did not become a protoplast by the first mechanism could from a protoplast by the second mechanism. The preparations contained two types of protoplasts, released from different sites of the mycelia. Those released from younger mycelia had dense cytoplasm and small vesicles. Those released from the older mycelia had less dense cytoplasm and larger vacuoles. In the case of regeneration, before producing normal mycelia, most of the protoplasts assumed aberrant tube and yeast-like-forms. Normal mycelia were produced at the end of the yeastlike-forms and sometimes in the middle of the aberrant tube.

• Korean Journal of Plant Tissue Culture
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• v.27 no.6
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• pp.429-434
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• 2000

Isolated protoplasts from ginseng (Panax ginseng C. A. Meyer) callus tissue were cultured in modified MS media supplemented with various concentrations of dimethylsulfoxide (DMSO). The cell wall regeneration rate and cell division efficiency of the protoplasts were increased significantly by 1% DMSO treatment. However, there was no difference in the viability of protoplasts between the DMSO treatment and non-treatment. Transmission electron microscopy revealed that the microtubules were oriented in parallel manner to the plasmalemma after 3 days of culture in medium with 1% DMSO. Further, interconnected cellulose microfibrils were observed on the outer surface of the 3-day-cultured protoplasts by scanning electron microscopy These structures shown by electron microscopy were not observed in protoplasts cultured on DMSO-free media. This studies indicates that DMSO supplemented in culture media seemed to stimulate the cell wall regeneration and cell divisions of protoplasts by forming microtubule organizing centers (MTOC).

• Journal of Plant Biotechnology
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• v.39 no.3
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• pp.133-139
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• 2012

The influences of ethylene inhibitors ($AgNO_3$ and silver thiosulfate) and cytokinins (BAP and TDZ) on shoot regeneration from cotyledon and hypocotyl explants of B. napus cv. Youngsan were investigated. The presence of $50{\mu}M$ Silver thiosulfate (STS) in shoot regeneration medium formed shoots at 60-68% after 3-4 weeks of culture, which was enhanced by 2-fold compared to that of Silver nitrate ($AgNO_3$). Moreover, cotyledon explants were more regenerative than hypocotyls; shoots from cotyledon explants began to occur 4-5 days earlier than that of hypocotyl explants. TDZ at a concentration of $8-10{\mu}M$ was effective for shoot regeneration, compared with BAP. Consequently, the optimal shoot regeneration response was observed in medium supplemented with $50{\mu}M\;STS+8{\mu}M\;TDZ$. In transmission electron microscopy (TEM) analysis, higher density of silver nanoparticles was shown to be accumulated widely inside the cell wall and plasmodesmata of regenerating leaf cultured in medium supplemented with $AgNO_3$. By contrast, in the cell cultured in medium with STS, fine-grained deposits were partly observed in the surroundings of the cell wall.

• Journal of Plant Biology
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• v.29 no.4
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• pp.263-284
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• 1986

Effects of putrescine, spermidine and spermine on the activity of D-glucose-6-phosphate cyclohydrolase in the Daucus carota L. protoplast cultured for 4 days and effects of polyamines on the incorporation of D-[u-14C]-glucose treated to protoplasts in culture-medium were investigated. The activity of D-glucose-6-phosphate cyclohydrolase was increased by polyamines and among them spermine was the most effective. Polyamiens increased protein synthesis and this due to the increasing effect of the polyamines on the synthesis of glycoprotein which is one of cell wall components. The synthesis of cell polysaccharides, such sa pectic substances, hemicelluloses and cellulose was increased by polyamines, which stimulated synthesis of pectin substances, and hemicellulose more greatly than that of cellulose, and spermidine was the most effective. In the light of the above results it seems that the polyamines increase cell wall regeneration by the stimulation of enzyme activities which synthesize cell wall components.