• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.186-186
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• 2005

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.224.2-225
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• 2000

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.194.2-194
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• 2003

No Abstract, See Full Text

• The Plant Pathology Journal
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• v.24 no.4
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• pp.375-383
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• 2008

It is well known that NtMEK2, a tobacco MAPK kinase, is the upstream kinase of both salicylic acid-induced protein kinase and wound-induced protein kinase. In addition, expression of $NtMEK2^{DD}$, a constitutively active mutant of NtMEK2, is known to induce multiple defense responses in tobacco. In this study, transgenic rice plants that contained an active or inactive mutant of NtMEK2 under the control of a steroid inducible promoter were generated and used to determine if a similar MAPK cascade is involved in disease resistance in rice. The expression of $NtMEK2^{DD}$ in transgenic rice plants resulted in HR-like cell death. The observed cell death was preceded by the activation of endogenous rice 48-kDa MBP kinase, which is also activated by Xanthomonas oryzae pv. oryzae, the bacterial blight pathogen of rice. In addition, prolonged activation of the MAPK induced the generation of hydrogen peroxide and up-regulated the expression of defense-related genes including the pathogenesis-related genes, peroxidases and glutathione S-transferases. These results demonstrate that NtMEK2 is functionally replaceable with rice MAPK kinase in inducing the activation of the downstream MAPK, which in turn induces multiple defense responses in rice.

• Korean Journal of Plant Tissue Culture
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• v.27 no.6
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• pp.441-445
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• 2000

In order to improve phosphate use efficiency of rice using phosphate transporter (PT), transgenic rice plants containing a tobacco PT gene were developed. Calli from Dongjinbyeo (Oryza sativa L.) were cocultured with A. tumefaciens LBA 4404 harboring PT gene. Multiplied calli were transferred to MS medium supplemented with 50 mg/L hygromycin, 500 mg/L carbenicillin, 2 mg/L kinetin, 0.1 mg/L NAA. After 2 weeks, hygromycin resistant shoots were obtained from the calli on the selection medium. The putative transgenic shoots were transferred to rooting MS medium supplemented with 250 mg/L cabenicillin. Plant regeneration rate from the calli was about 52%. Stable incorporation of the tobacco PT gene into rice genomic DNA was confirmed by PCR and Southern blot analysis.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2002.04b
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• pp.49-58
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• 2002

Oxidative stress derived from reactive oxygen species (ROS) is one of the major damaging factors in plants exposed to environmental stress. In order to develop the platform technology to solve the global food and environmental problems in the 21st century, we focus on the understanding of the antioxidative mechanism in plant cells, the development of oxidative stress-inducible antioxidant genes, and the development of transgenic plants with enhanced tolerance to stress. In this report, we describe our recent results on industrial transgenic plants by the gene manipulation of antioxidant enzymes. Transgenic tobacco plants expressing both superoxide dismutase (SOD) and ascorbate peroxidase (APX) in chloroplasts were developed and were evaluated their protection effects against stresses, suggesting that simultaneous overexpression of both SOD and APX in chloroplasts has synergistic effects to overcome the oxidative stress under unfavorable environments. Transgenic tobacco plants expressing a human dehydroascorbate reductase gene in chloroplasts were showed the protection against the oxidative stress in plants. Transgenic cucumber plants expressing high level of SOD in fruits were successfully generated to use the functional cosmetic purpose as a plant bioreactor. In addition, we developed a strong oxidative stress-inducible peroxidase promoter, SWPA2 from sweetpotato (Ipomoea batatas). We anticipate that SWPA2 promoter will be biotechnologically useful for the development of transgenic plants with enhanced tolerance to environmental stress and particularly transgenic cell lines engineered to produce key pharmaceutical proteins.

• Journal of Plant Biotechnology
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• v.29 no.2
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• pp.69-77
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• 2002

Oxidative stress derived from reactive oxygen species (ROS) is one of the major damaging factors in plants exposed to environmental stress. In order to develop the platform technology to solve the global food and environmental problems in the 21st century, we focus on the understanding of the antioxidative mechanism in plant cells, the development of oxidative stress-inducible antioxidant genes, and the development of transgenic plants with enhanced tolerance to stress. In this report, we describe our recent results on industrial transgenic plants by the gene manipulation of antioxidant enzymes. Transgenic tobacco plants expressing both superoxide dismutase (SOD) and ascorbate peroxidase (APX) in chloroplasts were developed and were evaluated their protection effects against stresses, suggesting that simultaneous overexpression of both SOD and APX in chloroplasts has synergistic effects to overcome the oxidative stress under unfavorable environments. Transgenic tobacco plants expressing a human dehydroascorbate reductase gene in chloroplasts were showed the protection against the oxidative stress in plants. Transgenic cucumber plants expressing high level of SOD in fruits were successfully generated to use the functional cosmetic purpose as a plant bioreactor. In addition, we developed a strong oxidative stress-inducible peroxidase promoter, SWPA2 from sweetpotato (lpomoea batatas). We anticipate that SWPA2 promoter will be biotechnologically useful for the development of transgenic plants with enhanced tolerance to environmental stress and particularly transgenic cell lines engineered to produce key pharmaceutical proteins.

• Horticultural Science & Technology
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• v.32 no.1
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• pp.91-99
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• 2014

The objective of this study is to identify cold-tolerance genes in Brassica rapa. In order to acheive this goal, we analyzed a KBGP-24K oligo chip data [BrEMD (B. rapa EST and Microarray Database)] using B. rapa ssp. pekinensis inbred line 'Chiifu' under cold stress condition ($4^{\circ}C$). Among 23,929 unigenes of B. rapa, 417 genes (1.7%) were primarily identified as cold responsive genes that were expressed over 5-fold higher than those of wild type control, and then a gene which has unknown function and has full length sequence was selected. It was named BrCSR (B. rapa Cold Stress Resistance). BrCSR was transformed using expression vector pSL101 to confirm whether BrCSR can enhance cold tolerance in tobacco plants. $T_1$ transgenic tobacco plants expressing BrCSR were selected by PCR and Southern hybridization analyses, and the function of BrCSR was characterized by expression level analysis and phenotype observation under cold stress condition. The expression level of BrCSR in transgenic tobacco plants increased up to about two folds in quantitative real-time RT-PCR assay and this was very similar to Northern blot hybridization analysis. Analysis of phenotypic characteristics clearly elucidated that transgenic tobaccos expressing BrCSR were more cold tolerant than wild type control under $4^{\circ}C$ treatment. Based on these results, we conclude that the over-expression of BrCSR might be closely related to the enhancement of cold tolerance.

• Korean Journal of Plant Tissue Culture
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• v.24 no.3
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• pp.153-160
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• 1997

Cucumber mosaic virus (CMV) leads to a cause of poor crop productivity and quality. To solve this problem, we attempted to develop a virus-resistance tobacco plants by using viral coat protein (CP) gene. Transgenic tobacco plants expressing CMV CP gene were analysed by the resistance upon CMV infection. The virus-resistance was measured in $\textrm{T}_{1}$, generation by the inhibition of plant growth and the expression of the mosaic symptoms infected with CMV. The transgenic lines were divided into four groups: highly resistant, resistant, moderate and susceptible based on their growth and symptom severity. Out of 39 transgenic lines, 16 lines showed significant virus-resistance. And of resistant lines, 2 lines were designated highly resistant based on the facts that they achieved similar plant height to that of non-infected tobacco plants and showed lower disease symptom than that of other lines. The steady state level of CP RNA and coat protein level were measured by northern blot and immunoblot analysis. The CP RNA was highly accumulated in most resistant and moderate lines but barely detected in susceptible lines. The coat protein was detected in most lines regardless of their resistance to CMV. from this result, virus-resistance appeared to correlate more with CP RNA level than the level of coat protein. However, in two highly resistant lines, CP RNA level was unexpectedly low. This unexpected phenomenon need to be further investigated.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.215-216
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• 2001

Mouse monoclonal antibody(mAb) with an antigen specificity for major histocompatibility complex class Il(MHC class II) was produced and secreted from tobacco cell suspension culture by successive sexual crossesu. Expression and secretion of assembled antibody was observed in transgenic tobacco cell suspension culture by wetern blot analysis.