• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2004.10a
• /
• pp.134-134
• /
• 2004

• Journal of Plant Biotechnology
• /
• v.29 no.2
• /
• pp.93-98
• /
• 2002

A VP6 fragments was subcloned with BamHI in the binary pMBP-1 vector under Califlower Mosaic Virus (CaMV) 355 promoter and neomycin phosphotransferase II (npt II) gene. The recombinant binary vector was mobilized into Agrobacterium-tumefaciens LBA4404 by the freeze-thaw method and potato (Solanum tubensum L. cv Desiree) was transformed by modified leaf-disc cocultivation. Shoots were induced on MS medium with 0.01 mg/L NAA, 0.1 mg/L GA$_3$, 2.0 mg/L Zeatin, 100.0 mg/L kanamycin, 500.0 mg/L carbenicillin. In order to identify the copy number of VP6 into potato plant, total genomic DNA was isolated from transgenic potato and analysed by Southern blotting. Genomic DNA and total mRNA analysis demonstrated the incorporation of the foreign gene into the potato genome, as well as their transcription.

• The Plant Pathology Journal
• /
• v.26 no.3
• /
• pp.209-215
• /
• 2010

Plant pathogenic oomycetes, such as Phytophthora spp., are the causal agent of the most devastating plant diseases. During infection, these pathogens accomplish parasitic colonization of plants by modulating host defenses through an array of disease effector proteins. These effectors are classified in two classes based on their target sites in the host plant. Apoplastic effectors are secreted into the plant extracellular space, and cytoplasmic effectors are translocated inside the plant cell, through the haustoria that enter inside living host cell. Recent characterization of some oomycete Avr genes showed that they encode effector protein with general modular structure including N-terminal conserved RXLR-DEER motif. More detailed evidences suggest that these AVR effectors are secreted by the pathogenic oomycetes and then translocated into the host plant cell during infection. Recent findings indicated that one of the P. infestans effector, Avrblb2, specifically induces hypersensitive response (HR) in the presence of Solanum bulbocastanum late blight resistance genes Rpi-blb2. On the other hand, another secreted RXLR protein PexRD8 originated from P. infestans suppressed the HCD triggered by the elicitin INF1. In this review, we described recent progress in characterized RXLR effectors in Phytophthora spp. and their dual functions as modulators of host plant immunity.

• Journal of Plant Biotechnology
• /
• v.36 no.1
• /
• pp.81-86
• /
• 2009

An efficient and reproducible plant regeneration system was established using transverse thin cell layers (tTCLs) in five cultivars of Brassjca juncea L. The effects of medium conditions, explant types (tTCLs of hypcotyl and cotyledonary petiole) on shoot regeneration were examined in this study. The maximum shoot regeneration frequency was obtained in Murashige and Skoog (MS) medium supplemented with 4 mg/L 6-benzylaminopurine (BA) and 0.2 mg/L 1-naphthaleneacetic acid (NAA). The hypocotyls derived tTCL explants had more shoot regeneration frequency (52%) than the cotyledonary petiole derived tTCL explants. Shoot induction was further improved by the addition of silver nitrate ($AgNO_3$) in the regeneration medium. A significant genotypic effect was also observed between the five cultivars; Rai-5 displayed higher capacities to produce shoots than other cultivars. Regenerated shoots were rooted on MS basal medium without PGRs which induced 90% of roots. The plantlets established in greenhouse conditions with 99% survival, flowered normally and set seeds. The regenerated plants were fertile and identical to source plants.

• Journal of Plant Biotechnology
• /
• v.5 no.1
• /
• pp.69-77
• /
• 2003

Brassinosteroids are known to promote cell elongation in a wide range of plant species but their effect on cell division has not been extensively studied. The effect of brassinolide on the kinetics and final division frequencies of regenerating petal protoplasts of Petunia hybrida Vilm v. Comanche was examined. Under optimal auxin and cytokinin conditions, 10-100 nM brassinolide not only reduced the time of first cell division by 4.5 days but also altered the final division frequencies after 10 days of culture. One micromolar brassinolide showed the same acceleration of first cell division but inhibited the final division frequency by approximately 9%. Under sub-optimal auxin conditions, 10-100 nM brassinolide accelerated the first cell division, but no significant increase in the 8-10 days final division frequencies. Isolated protoplasts may provide a useful model system for the investigation of the molecular mechanisms of brassinosteroid action on cell division and proliferation in higher plants.

• Journal of Plant Biotechnology
• /
• v.5 no.1
• /
• pp.63-67
• /
• 2003

Brassinosteroids are known to promote cell elongation in a wide range of plant species but their effect on cell division has not been extensively studied. The effect of brassinolide on the kinetics and final division frequencies of regenerating petal protoplasts of Petunia hybrida Vilm v. Comanche was examined. Under optimal auxin and cytokinin conditions, 10-100 nM brassinolide not only reduced the time of first cell division by 4.5 days but also altered the final division frequencies after 10 days of culture. One micromolar brassinolide showed the same acceleration of first cell division but inhibited the final division frequency by approximately 9%. Under sub-optimal auxin conditions, 10-100 nM brassinolide accelerated the first cell division, but no significant increase in the 8-10 days final division frequencies. Isolated protoplasts may provide a useful model system for the investigation of the molecular mechanisms of brassinosteroid action on cell division and proliferation in higher plants.

• Analytical Science and Technology
• /
• v.35 no.4
• /
• pp.181-188
• /
• 2022

This paper describes a comparative analysis of yeast cell viability at exponential and stationary growth phases using multiple conventional techniques and statistical tools. Overall, cellular responses to various viability assays were asynchronous. Results of optical density measurement and direct cell counting were asynchronous both at exponential and stationary phases. Proliferative capacity measurement using SP-SDS indicated that cells at the end of the stationary phase were proliferative as much as exponentially growing cells. Metabolic activity assays using two different dyes concluded that the inside of cells at stationary phase is slightly less reducing compared to that of exponentially growing cells, implying that the metabolic activity imperceptibly declined as cells were aged. These results will be helpful to understand the details of yeast cell viability at exponential and stationary growth phases.

• Journal of the Korean Wood Science and Technology
• /
• v.46 no.2
• /
• pp.166-177
• /
• 2018

Plant essential oils are defined as fragrant volatile oils extracted from leaves, stems, fruits, flowers, and roots of a plant. Such oils are composed of multiple components and multiple functions. By accumulation of inductive information, various plant essential oils have been studied for using in therapeutic medicine for various diseases. Despite of the apparent advantages of essential oils as a source of therapeutic medicines, plant essential oils have many limitations, including cytotoxic side effects. Therefore, it is necessary to evaluate the toxicity and the mechanisms of cytotoxicity of such oils. In this study, we evaluated the cytotoxicity to human-derived cell lines of 10 plant essential oils provided by National Institute of Forest Science (i.e., Larix kaempferi; Abies holophylla; Zanthoxylum ailanthoides; Pinus parviflora; Tsuga sieboldti; Chamaecyparis pisifera; Cryptomeria japonica; Pinus densiflora; Illicium anisatum; Pinus thunbergii). Cytotoxicity evaluations were accomplished by using CCK-assays and PCR-based cytotoxicity-related marker gene analyses with A549 cell line, and the Detroit551 cell line which are lung and skin cell line. The genes were analyzed included caspase-3 has a role in cell apoptosis, and the other cyclinA, cyclinB, cyclinD, and cyclinE regulated cell cycling for the cell proliferation. By examining the five cytotoxicity-related marker genes by performing real-time PCR and examined the cytostatic gene regulation associated with the various essential oils. The results of this study showed that the degree of cytotoxicity and the cytostatic gene regulation which could give precious information for using the plant essential oil for the clinical usages.

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2003.04a
• /
• pp.116-116
• /
• 2003

• Microbiology and Biotechnology Letters
• /
• v.18 no.4
• /
• pp.327-330
• /
• 1990

The effects of various plant growth regulators, both auxins and cytokinins, on cell growth and berberine production were investigated in cell suspension cultures of Thafictrum rugosum. Indole-%-acetic acid (IAA) was found to be the best for berberine production among five examined plant growth regulators and the optimum concentration of IAA was 1 $\mu \textrm M$. The enhancement compared to control 2, 4-dichlorophenoxyacetic acid (2, 4-D) was more than 60%. Simultaneous addition of cytokinins such as kinetin and 6-benzylamiroyurine (BA) was inhibitory.