• Journal of Microbiology and Biotechnology
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• v.19 no.9
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• pp.966-971
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• 2009

Peroxidase from Coprinus cinereus (CiP) has attracted attention for its high specific activity and broad substrate spectrum compared with other peroxidases. In this study, the functional expression of this peroxidase was successfully achieved in the methylotrophic yeast Pichia pastoris. The expression level of CiP was increased by varying the microbial hosts and the expression promoters. Since a signal sequence, such as the alpha mating factor of Saccharomyces cerevisiae, was placed preceding the cDNA of the CiP coding gene, expressed recombinant CiP (rCiP) was secreted into the culture broth. The Mut Pichia pastoris host showed a 3-fold higher peroxidase activity, as well as 2-fold higher growth rate, compared with the $Mut^s $ Pichia pastoris host. Furthermore, the AOX1 promoter facilitated a 5-fold higher expression of rCiP than did the GAP promoter.

• Journal of Plant Biotechnology
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• v.4 no.4
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• pp.143-150
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• 2002

A strong oxidative stress-inducible peroxidase promoter (referred to as SWPA2 promoter) was cloned from tell cultures of sweetpotato (Ipomoea batatas) and characterized in transgenic tobacco cultured cells in terms of biotechnological applications. Employing a transient expression assay in tobacco protoplasts, with five different 5'-deletion mutants of the SWPA2 promoter fused to the $\beta$-glucuronidase (GUS) reporter gene, the 1314 bp deletion mutant showed approximately 30 times higher GUS expression than the CaMV 35S promoter. The expression of GUS activity in suspension cultures of transgenic cells derived from transgenic tobacco leaves containing the -1314 bp SWPA2 promoter-GUS fusion was strongly expressed following 15 days of subculture compared to other deletion mutants, suggesting that the 1314 bp SWPA2 promoter will be biotechnologically useful for the development of transgenic cell lines engineered to produce key pharmaceutical proteins. In this respect, we developed transgenic cell lines such as tobacco (Nicotiana tabacum L. BY-2), ginseng (Panax ginseng) and Siberian ginseng (Acanthopanax senticosus) using a SWPA2 promoter to produce a human lactoferrin (hLf) and characterized the hLf production in cultured cells. The hLf production monitored by ELISA analysis in transgenic BY-2 cells was directly increased proportional to cell growth and reached a maximal level (up to 4.3% of total soluble protein) at the stationary phase in suspension cultures. The SWPA2 promoter should result in higher productivity and increased applications of plant cultured cells for the production of high-value recombinant proteins.

• Journal of Microbiology and Biotechnology
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• v.8 no.1
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• pp.92-95
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• 1998

Overproduction of Escherichia coli thiol peroxidase in the periplasmic space was achieved by locating the appropriate gene on a downstream region of the strong T7 promoter. E. coli strain BL21 carrying the recombinant plasmid pSK-TPX was induced by IPTG, lysed, and analyzed by SDS-polyacrylamide gel electrophoresis. A large amount of the overexpressed thiol peroxidase was located in the periplasmic space. A homogeneous thiol peroxidase was obtained from E. coli osmotic shock fluid by simple one-step gel permeation chromatography.

• BMB Reports
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• v.32 no.1
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• pp.51-59
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• 1999

The Korean radish cationic peroxidase (KRCP) promoter, comprising nucleotides -471 to +704 relative to the transcriptional initiation site, was fused to the GUS gene and transformed to tobacco BY-2 cells. We examined how auxin (2,4-dichlorophenoxyacetic acid, 2,4-D), cytokinin (6-benzylaminopurine, BAP), gibberellic acid ($GA_3$), abscisic acid (ABA), methyl jasmonate (MeJA), and phosphatidic acid (PA) affect the GUS expression in the presence or absence of 2,4-D in a modified LS medium. Exogenous 2,4-D or BAP greatly decreased the GUS expression regulated by the KRCP promoter in a modified LS medium containing 0.2 mg/l 2,4-D. $GA_3$ increased the GUS expression and ABA completely reduced the inductive effect of $GA_3$. The GUS expression was also increased dose-dependently by plant defense regulators, MeJA and PA. In contrast to the above results, auxin deprivation from the modified LS medium increased the GUS expression after treatment with exogenous 2,4-D whereas BAP still greatly decreased the GUS expression dose-dependently. $GA_3$ or MeJA slightly decreased the GUS expression. The data suggest that auxin deprivation changes the sensitivity of the suspension cells to exogenous chemicals and that the regulation of the KRCP promoter by 2,4-D, $GA_3$, and MeJA is dependent on auxin, whereas the regulation by BAP is not. This study will be valuable for understanding the function and expression mode of the Korean radish cationic peroxidase in Korean radish.

• BMB Reports
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• v.29 no.1
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• pp.52-57
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• 1996

A specific DNA fragment from Korean radish (Raphanus sativus L.) was amplified by performing PCR with oligonucleotide primers which correspond to the highly conserved regions of plant peroxidases. The size of the PCR product was ca. 400 bp, as expected from the known plant peroxidase genes. Comparison of the nucleotide and deduced amino acid sequences of the PCR product to those of other plant peroxidase-encoding genes revealed that the amplified fragment corresponded to the highly conserved region I and III of plant peroxidases. By screening a genomic library of Korean radish using the amplified fragment as a probe, two positive clones, named prxK1 and prxK2, were isolated. Restriction mapping studies indicated that the 5.2 kb Sail fragment of the prxK1 clone and the 4.0 kb EcoRI fragment of the prxK2 clone encode separate isoperoxidase genes. Analyses of the promoter region of the prxK1 clone shows that putative CAAT box, CMT box, and TGA1b binding sequence (5' TGACGT) are present 718 bp upstream from the start codon.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2004.05a
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• pp.59-59
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• 2004

• Molecules and Cells
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• v.39 no.8
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• pp.631-638
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• 2016

Glutathione peroxidase 3 (GPx3), an antioxidant enzyme, acts as a modulator of redox signaling, has immunomodulatory function, and catalyzes the detoxification of reactive oxygen species (ROS). GPx3 has been identified as a tumor suppressor in many cancers. Although hyper-methylation of the GPx3 promoter has been shown to down-regulate its expression, other mechanisms by which GPx3 expression is regulated have not been reported. The aim of this study was to further elucidate the mechanisms of GPx3 regulation. GPx3 gene analysis predicted the presence of ten glucocorticoid response elements (GREs) on the GPx3 gene. This result prompted us to investigate whether GPx3 expression is regulated by the glucocorticoid receptor (GR), which is implicated in tumor response to chemotherapy. The corticosteroid dexamethasone (Dex) was used to examine the possible relationship between GR and GPx3 expression. Dex significantly induced GPx3 expression in H1299, H1650, and H1975 cell lines, which exhibit low levels of GPx3 expression under normal conditions. The results of EMSA and ChIP-PCR suggest that GR binds directly to GRE 6 and 7, both of which are located near the GPx3 promoter. Assessment of GPx3 transcription efficiency using a luciferase reporter system showed that blocking formation of the GR-GRE complexes reduced luciferase activity by 7-8-fold. Suppression of GR expression by siRNA transfection also induced down-regulation of GPx3. These data indicate that GPx3 expression can be regulated independently via epigenetic or GR-mediated mechanisms in lung cancer cells, and suggest that GPx3 could potentiate glucocorticoid (GC)-mediated anti-infla-mmatory signaling in lung cancer cells.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2002.04a
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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 21s1 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 Aquaculture
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• v.10 no.1
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• pp.33-37
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• 1997

construct containing reporter gene(pFV4CAT) regulated by carp $\beta$-actin promoter was microinjected into the one-cell stage egg of mud loach (Misgurnus mizolepis), and was successfully expressed, possibly by the integration into the genome. Both mean hatching success and early survival of the microinjected groups were not significantly different with those of control groups (P>0.05). The incidence of transgene was ranged from 7 to 48% based on the PCR and/or Southern blot analyses with the DNA prepared from fin or blood tissue. The spatial and temporal patterns of expression of the pFV4CAT gene, measured by in situ immunohistochemical analysis peroxidase-conjugated anti-CAT antibody, were variable among the experimental individuals. These results suggest that carp $\beta$-actin promoter is effective to express other transgene in mud loach, such that this promoter can be useful in the generation of valuable transgenic mud loach.

• 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.