• Journal of Plant Biotechnology
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• v.2 no.3
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• pp.143-149
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• 2000

An Efficient in vitro regeneration system and an optimized Agrobacterium mediated transformation protocol are described, based on the use of young seedling cotyledons of Capsicum annuum L. Optimal regeneration efficiency can be obtained by cultivating cotyledon explants on media containing 4 mg/L benzyladenine and 0.1 mg/L indolacetic acid. The effect of antibiotics used to eliminate Agrobacteria, as well as the toxic level of some generally used selection agents (kanamycin, geneticin, hygromycin, phosphinotricin and methotrexate) in regenerating pepper tissues were determined. To enable the comparison of different selection markers in identical vector background, a set of binary vectors containing the marker genes for NPTII, HPT, DHFR and BAR respectively, as well as the CaMV 35S promoter/enhancer-GUS chimaeric gene was constructed and introduced into four different Agrobacterium host strains.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.04a
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• pp.6-9
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• 2005

Plant biotechnology involving genetic modification has been rather controversial. However, the major issues related to safety are being addressed by continued improvements in technology. Some of the related facts will be highlighted to set the tone for a scientific discussion on the possibilities of using the technology for crop improvement. Our main research interest is to understand the molecular regulation of shoot bud regeneration in plant tissue culture, which is essential for crop improvement by biotechnology. We have isolated and characterized some genes that are associated with adventitious shoot regeneration. These include a MADS-box cDNA (PkMADS1) from paulownia kawakamii, which regulates vegetative shoot development and in vitro shoot regeneration from leaf explants. Another gene we have characterized from petunia codesfor a cytokinin binding protein (PETCBP). Preliminary functional analysis of this gene indicated that this also affects adventitious shoot bud initiation. Also, the antisense suppression of this gene in petunia causedexcessive branching. Results from our work and selected other publications will be used to highlight the possibilities of manipulation of such genes to improve crop species.

• Animal cells and systems
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• v.5 no.2
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• pp.91-99
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• 2001

Vertebrates regenerate tissues in three ways: proliferation of cells that maintain some or all of their differentiated structure and function, redifferentiation of mature cells followed by proliferation and redifferentiation into the same cell type or transdetermination to another cell type, and activation of restricted lineage stem cells, which have the ability to transdetermine to different lineages under the appropriate conditions. The behavior of the cells during regeneration is regulated by growth factors and extracellular matrix molecules. Some non-regenerating tissues are now known to harbor stem cells which, though they form scar tissue in vivo, are capable of producing new tissue-specific cells in vitro, suggesting that the injury environment inhibits latent regenerative capacity. Regenerative medicine seeks to restore tissues via transplantation of stem cell derivatives, implantation of bioartificial tissues, or stimulation of regeneration in vivo. These approaches have been partly successful, but several research issues must be addressed before regenerative medicine becomes a clinical reality.

• Horticultural Science & Technology
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• v.17 no.6
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• pp.765-767
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• 1999

Experiments were conducted to find out the optimum cultural conditions for adventitious shoot regeneration from leaf segments of Gypsophila paniculata L. Thidiazuron (TDZ) was remarkably effective for the regeneration of leaf segment in Gypsophila paniculata compared with BA and kinetin. TDZ showed the highest rate of regeneration at $3.0mg{\cdot}L^{-1}$, while kinetin did not affect the regeneration. BA in the medium increased vitrification. Shoot formation efficiency was much higher on $0.3mg{\cdot}L^{-1}$ of IAA-containing media than NAA-containing media. Regeneration of leaf segments was induced with the agar concentrations of 1.0, 1.2 and 1.6%. Dark treatment at the initial stage of the culture increased the rate of regeneration up to 75%. The leaf explants from the 3rd subcultured stock plants after meristem culture, showed the highest adventitious shoot regeneration efficiency.

• Korean Journal of Medicinal Crop Science
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• v.14 no.2
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• pp.92-95
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• 2006

A method for plant regeneration via organogenesis from Pelagonium inquinans leaf disc has been developed. Mature leaf explants were collected from field-grown plants and used for the induction of adventitious shoot regeneration on Murashige and Skoog (MS) medium supplemented with 3% (w/v) sucrose plus plant growth regulators. Maximum shoot organogenesis, with $11.8{\pm}1.5$ shoots (98.6%) per leaf disc, was obtained with $2\;mg/l$ $N^6-benzyladenine$ (BA) and $0.5\;mg/l$ ${\alpha}-naphthyleneacetic$ acid (NAA) in 30 days. For rooting, the in vitro proliferated and elongated shoots were excised into 1.5-2 cm in length microcutting, which were plated individually on an half-strength MS (1/2MS) medium supplemented with 2% (w/v) sucrose plus various concentrations of indole-3-butyric acid (IBA). Shoots rooted with a frequency of 100% following culture on 1/2MS medium containing $0.5\;mg/l$ IBA.

• Journal of Plant Biotechnology
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• v.45 no.2
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• pp.146-153
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• 2018

Lilium ledebourii Bioss is a wild species of Lilium, which grows naturally in some provinces of Iran. Previous studies on Lilium tissue culture have been linked to direct regeneration and a few studies have been conducted on indirect regeneration, which has been studied under bright conditions. In this study, for the first time in the world, all the stages of indirect regeneration (callus induction, shoot and root induction) have been studied under dark conditions. Callus formation and the regeneration levels of L. Ledebourii Bioss were examined for three replicates in an MS (Murashige and Skoog) medium with different hormonal compositions and by using a factorial experiment in the framework of a completely random plan. For callus initiation, 2,4-D and kinetin hormones were used in five and four levels, respectively, as auxin and cytokinin. Results showed that the highest percentage of the callus was found in $3{\mu}M$ of 2,4-D and $0.5{\mu}M$ of kinetin. In terms of callus wet weight, the highest amount was found in $3{\mu}M$ of 2,4-D and $0.5{\mu}M$ of kinetin. In addition, in terms of diameter, the highest amount was found in $3{\mu}M$ of 2,4-D, and $0.5{\mu}M$ of kinetin. In summary, the 2,4-D hormone had a major impact on the percentage of regeneration increase so that the best response was related to the composition of $3{\mu}M$ of 2,4-D, and $0.1{\mu}M$ of kinetin. This study contended that auxin and cytokinin can induce long shoots and roots through cell elongation in dark condition.

• Molecules and Cells
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• v.41 no.5
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• pp.476-485
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• 2018

Although tectorigenin (TG), a major compound in the rhizome of Belamcanda chinensis, is conventionally used for the treatment of inflammatory diseases, its effects on osteogenesis and osteoclastogenesis have not been reported. The objective of this study was to investigate the effects and possible underlying mechanism of TG on in vitro osteoblastic differentiation and in vivo bone formation, as well as in vitro osteoclast differentiation and in vivo bone resorption. TG promoted the osteogenic differentiation of primary osteoblasts and periodontal ligament cells. Moreover, TG upregulated the expression of the BMP2, BMP4, and Smad-4 genes, and enhanced the expression of Runx2 and Osterix. In vivo studies involving mouse calvarial bone defects with ${\mu}CT$ and histologic analysis revealed that TG significantly increased new bone formation. Furthermore, TG treatment inhibited osteoclast differentiation and the mRNA levels of osteoclast markers. In vivo studies of mice demonstrated that TG caused the marked attenuation of bone resorption. These results collectively demonstrated that TG stimulated osteogenic differentiation in vitro, increased in vivo bone regeneration, inhibited osteoclast differentiation in vitro, and suppressed inflammatory bone loss in vivo. These novel findings suggest that TG may be useful for bone regeneration and treatment of bone diseases.

• Journal of Plant Biotechnology
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• v.34 no.2
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• pp.161-166
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• 2007

In vitro shoot regeneration and multiple shoot induction has been obtained from the stolen node explants in Eremochloa ophiuroides (Munro) Hack. The highest number of shoots ($10.66{\pm}0.21$) was observed from initial explants after one month culture duration on Murashige and Skoog (MS) medium containing 6-benzyladenine (BA: 0.5 mg/l). First generation shoot was excised and sub-cultured on the same fresh media for further multiplication of shoots. An enhanced number of second round shoots ($15.33{\pm}0.21$) was obtained compared to the initial culture media containing BA (0.5 mg/l). The number of shoots/stolon node was higher among all the concentrations of BA than kinetin (KN). In vitro regenerated shoots were successfully rooted in the phytohormone free MS medium. Plantlets generated with roots were transferred to pots containing compound mixture of soil and kept in green house conditions. Acclimatized plants showed 100% survival rate with normal morphology in green house conditions. The present study demonstrates the effect of explant and different plant growth regulators towards in vitro response in E. ophiuroides. Moreover, the study reveals the effect of cytokinin on induction of shoot number per stolen node explant in E. ophiuroides.

• Journal of Periodontal and Implant Science
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• v.26 no.3
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• pp.681-688
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• 1996

Periodontal regeneration requires the migration and proliferation of gingival fibroblasts and periodontal ligament cells. These cellular events are influenced and regulated by growth factors and some drugs. The purpose of this study is to examine the effect of Rhizoma coptidis and Centella asiatica extracts on human gingival fibroblasts. Gingival fibroblasts were primarily cultured from extracted premolar with non-periodontal diseases. Cells were cultured with ${\alpha}-MEM$ at $37^{\circ}C$, 5% $CO_2$, 100% humidity incubator for 2 or 3 days, as a measure of cell proliferation potential, it was examined that the DNA synthesis using $[^3H]-thyrnidine$ incorporation, the cell numbers (with or without dye), and cell viabilities. Rhizoma coptidis is increased the proliferation of gingival fibroblasts at concentration of $10^{-9}g/ml$, but Centella asiatica is decreased the proliferation at all concentrations. This study demonstrated that Rhizoma coptidis is a potential mitogen for human gingival fibroblasts in vitro, and we can expect the usefulness of this drug in periodontal regeneration.

• Korean Journal of Plant Resources
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• v.11 no.1
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• pp.1-8
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• 1998

This study was conducted to establish mass propagation system from the axillary bud culture of chrysanthemum zawadskii H. which was used as material of medicinal plants. Shoot egeneration was better on MS medium with NAA and BA. The optimum concentraions of growth regulator for shoot regeneration differed depending on accessionsof C. Zawadskii. Shoot regeneration in Keungucheolcho was better on MS Medium with NAA 0.01mg/1 and BA 0.1mg/1 while Hyangrobonggucheocho was better with NAA 0.1mg/1and BA 0.3mg/1. Addition of NAA into medium was effective for induction of root from shoots regenerated. Shoot multiplcation was more effective when 10mg/1 spermine was added into medium than when other polyamines were treated ino medium . Randomly and specifically amplified polymorphic DAC banding patterns based on polymerase chain reaction (PCR) analysis were used to assess the genetic variation of plants regenerated from in vitro culture.