• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.1
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• pp.16-22
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• 2005

cDNA for oxidosqualene cyclase was cloned by a homology-based PCR method and sequenced from Centella asiatica. In a sequences analysis, the putative polypeptide of C. asiatica cycloartenol synthase (CaCYS) deduced from the 2,274 bp nucleotide sequence, consisted of 758 amino acids and had a molecular mass of 86.3 kD. The predicted amino acid sequence exhibited high homology to that of PNX (cycloartenol synthase) from Panax ginseng ($89\%$). Southern blot analysis suggests that CaCYS may be present in one copy of the C. asiatica genome. If methyl jasmonate (MJ) is applied exogenously to plants, not only triterpene saponins are accumulated in tissues, but also it produces effects such as growth inhibition and the promotion of ethylene production. In order to investigate the effect of MJ and thidiazuron (TDZ), a cytokinin that plays a role as an antisenescence agent in several plants, on the level of CaCYS mRNA, we performed northern blot analysis. When MJ is alone treated by adding to culture medium, CaCYS transcripts were inhibited. However, sustained levels of the expression of CaCYS, by adding TDZ to the medium despite MJ treatments, were demonstrated in C. asiatica leaves.

• Plant Biotechnology Reports
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• v.5 no.4
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• pp.367-373
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• 2011

Linum album accumulates anti-tumor podophyllotoxin (PTOX) and its related lignans, which were originally isolated from an endangered species Podophyllum. In the present study, we examined the effects of five fungal extracts on the production of lignans in L. album cell cultures. Fusarium graminearum extract induced the highest increase of PTOX [$143{\mu}g\;g^{-1}$ dry weight (DW) of the L. album cell culture], while Rhizopus stolonifer extract enhanced the accumulation of lariciresinol up to $364{\mu}g\;g^{-1}$ DW, instead of PTOX. Typical elicitors, such as chitin, chitosan, or methyl jasmonate (MeJA), were shown to be less effective in lignan production in L. album cell cultures. These results verified the advantages of fungal extracts to increase lignan production in L. album cell culture, and suggested potential on-demand metabolic engineering of lignan biosynthesis using differential fungal extracts.

• Journal of Plant Biotechnology
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• v.45 no.4
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• pp.340-346
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• 2018

In this study, the effect of elicitors such as yeast extract (YE), methyl jasmonate (MeJA) and salicylic acid (SA) on the accumulation of eurycomanone in Eurycoma longifolia cell cultures were investigated. Suspension cells of E. longifolia was cultured in Murashige and Skoog (MS) medium supplemented with 30 g/L sucrose, 1.25 mg/L naphthaleneacetic acid (NAA) and 1 mg/L kinetin at a shaking speed of 120 rpm. Elicitors were added in the culture at different concentrations and times to stimulate eurycomanone accumulation in the Eurycoma longifolia cells. Eurycomanone content was determined by HPLC with a C18 column, flow rate of 0.8 mL/min, run time of 17.5 min, and a detector wavelength of 254 nm. The stationary phase was silica gel and the mobile phase was acetonitrile: $H_2O$. Non-elicited cells were used as the control. The study showed the effect of different elicitor concentrations, YE at 200 mg/L, MeJA at $20{\mu}M$ and SA at $20{\mu}M$ stimulated high production of eurycomanone. In which, treatment of $20{\mu}M$ MeJA after 4 days of culture resulted in the highest accumulation of this compound (17.36 mg/g dry weight), approximately 10-fold higher than that of untreated cells (1.70 mg/g dry weight).

• Plant Breeding and Biotechnology
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• v.5 no.3
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• pp.204-212
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• 2017

There is a growing preference for using doubled haploids (DHs) in maize breeding programs because they reduce the time required to generate and evaluate new lines to 2 years or less. However, there is an urgent need for efficient techniques that accurately discriminate between haploid and diploid maize kernels. Here, we investigate the effects of several hormones and chemicals on the germination of haploid and diploid maize kernels, including auxin, cytokinin, ethylene, abscisic acid (ABA) biosynthesis inhibitor (fluridone), ABA catabolism inhibitor (diniconazole), methyl jasmonate (MeJA), and NaCl. Ethylene effectively stimulated the germination of both haploid and diploid maize kernels. The ABA biosynthesis inhibitor fluridone, the ABA catabolism inhibitor diniconazole, and MeJA selectively stimulated the germination of haploid maize kernels. By contrast, gibberellin, 1-naphthaleneacetic acid (NAA), kinetin, and NaCl inhibited the germination of both haploid and diploid maize kernels. These results indicate that the germination of haploid maize kernels is selectively stimulated by fluridone and diniconazole, and suggest that ABA-mediated germination of haploid maize kernels differs from that of diploid maize kernels and other plant seeds.

• Journal of Bio-Environment Control
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• v.27 no.1
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• pp.94-101
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• 2018

Mugwort (Artemisia princeps) is a medicinal plant that has a substance called euphatilin, which is effective for cell damage and gastritis recovery. The objectives of this study were to investigate the annual growth characteristics of Artemisia princeps in greenhouse and to increase the eupatiline content by environmental stresses. Growth and eupatilin content of the plants were compared after 6 weeks of seedling and subsequent 8 weeks of greenhouse cultivation. Photosynthesis of mugwort plants did not saturate even at a relatively high light intensity of $1,200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Growth rate of the plants reached its highest at two weeks after transplanting and began to decrease since 8 weeks after transplanting. The plants showed typical characteristics of a perennial herbaceous plant as they were sensitive to seasonal changes. In particular, the plants showed high growth and eupatilin content in spring and summer as vegetative growth periods, but flowering and wintering caused considerable decreases in growth and eupatilin content in fall and winter. Therefore, application of night interruption is essential for year-round cultivationof the plant. Two stresses and a elicitor were treated: drought stresses by stopping irrigation at 5, 6, 7, and 8 days before harvest; salt stresses with nutrient solution concentrations of 2, 4, 6, 8, and $10dS{\cdot}m^{-1}$ by adding sodium chloride at 3 days before harvest; and foliar applications of methyl jasmonates of 12.5, 25, 50, and $100{\mu}M$ at 3 days before harvest. Significant increase in eupatilin content was observed at drought stresses of 7- and 8-days of irrigation stop and foliar application of $25{\mu}M$ methyl jasmonate, while no significant increase observed at salt stresses. From the results, it was confirmed that the environmental treatments can improve the productivity and quality of Artemisia princeps as a phamaceutical raw material.

• BMB Reports
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• v.41 no.2
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• pp.112-118
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• 2008

Camptothecin is an anti-cancer monoterpene indole alkaloid. The gene encoding 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase (designated as CaHDR), the last catalytic enzyme of the MEP pathway for terpenoid biosynthesis, was isolated from camptothecin-producing Camptotheca acuminata. The full-length cDNA of CaHDR was 1686 bp encoding 459 amino acids. Comparison of the cDNA and genomic DNA of CaHDR revealed that there was no intron in genomic CaHDR. Southern blot analysis indicated that CaHDR belonged to a low-copy gene family. RT-PCR analysis revealed that CaHDR expressed constitutively in all tested plant organs with the highest expression level in flowers, and the expression of CaHDR could be induced by 100 ${\mu}M$ methyl-jasmonate (MeJA), but not by 100 mg/L salicylic acid (SA) in the callus of C. acuminata. The complementation of CaHDR in Escherichia coli ispH mutant MG1655 demonstrated its function.

• Journal of Ginseng Research
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• v.37 no.3
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• pp.361-370
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• 2013

A lysine histidine transporter (LHT) cDNA was isolated and characterized from the roots of Panax ginseng, designated PgLHT. The cDNA is 1,865 bp with an open reading frame that codes for a protein with 449 amino acids and a calculated molecular mass of 50.6 kDa with a predicted isoelectric point of 8.87. Hydropathy analysis shows that PgLHT is an integral membrane protein with 9 putative membrane-spanning domains. Multiple sequence alignments show that PgLHT shares a high homology with other plant LHTs. The expression profile of the gene was investigated by real-time quantitative polymerase chain reaction during various chemical treatments. PgLHT was up-regulated in the presence of abscisic acid, salicylic acid, methyl jasmonate, NaCl, and amino acids. To further explore the function of PgLHT gene, full-length cDNA of PgLHT was introduced into P. ginseng by Agrobacterium rhizogenes A4. The overexpression of PgLHT in the hairy roots led to an obviously increase of biomass compared to the controls, and after addition of the amino acids, the overexpressed-PgLHT hairy roots grew more rapidly than untreated controls during early stage of the culture cycle. The results suggested that the PgLHT isolated from ginseng might have role in the environmental stresses and growth response.

• Korean Journal of Agricultural Science
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• v.45 no.3
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• pp.365-378
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• 2018

Anthracnose caused by Colletotrichum gloeosporioides, which is one of the major diseases of red dates, causes severe damages in jujube (Zizyphus jujuba Miller) production in Korea. This study was done to evaluate the inhibition of anthracnose occurrence and pathogen growth by the treatment of environment-friendly materials such as a Bordeaux mixture and loess-sulfur mixture and by defense-response signaling in jujube. The in vitro test of the environment-friendly materials and signaling molecules that were routinely applied did not exhibit any antifungal activities against the pathogen for jujube anthracnose. The Bordeaux mixture and loess-sulfur mixture at a two-fold concentration showed inhibition zones that were 16.0 and 20.3 mm in diameter, respectively. In the pathogen inoculation test with detached jujube tree leaves, while treatment with the environment-friendly materials diluted by half showed no inhibition of lesion development, they did show inhibition of lesion development when they were routinely applied to the leaves. In detached jujube fruits inoculated with the pathogen, better suppressive effects by the treatment of the environment-friendly materials were seen in the fruits at a young stage rather than in the ripening stage. The in vivo test with jujube trees in pots showed that the treatment of salicylic acid (1 mM) resulted in the best suppressive effects against lesion development. The results suggest that it is possible to manage the incidence of anthracnose by the treatment of environment-friendly materials such as the Bordeaux and loess-sulfur mixtures and signaling chemicals such as ethephon, hydrogen peroxide, methyl jasmonate, and salicylic acid in jujube trees and fruits. Consequently, these findings suggest that environment-friendly materials and defense response signaling molecules could be used as suitable candidates for sustainable agrochemicals to manage anthracnose in jujube production.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.78.2-79
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• 2003

Pepper defensin ( CADEFl) clone was isolated from cDNA library constructed from pepper leaves infected with avirulent strain Bv5-4a of Xanthomonu campestris pv. vesicatoria. The deduced amino acid sequence of CADEFl is 82-64％ identical to that of other plant defensins. Putative protein encoded by CADEFl gene consists of 78 amino acids and 8 conserved cysteine residues to form four structure-stabilizing disulfide bridges. Transcription of the CADEF1 gene was earlier and stronger induced by X campestris pv. vesicatoria infection in the incompatible than in the compatible interaction. CADEF1 mRNA was constitutively expressed in stem, root and green fruit of pepper. Transcripts of CADEFl gene drastically accumulated in pepper leaf tissues treated With Salicylic acid (SA), methyl jasmonate (MeJA), abscisic acid (ABA), hydrogen Peroxide (H$_2$O$_2$), benzothiadiazole (BTH) and DL-${\beta}$-amino-n-butyric acid (BABA). In situ hybridization results revealed that CADEF1 mRNA was localized in the phloem areas of vascular bundles in leaf tissues treated with exogenous SA, MeJA and ABA. Strong accumulation of CADEF1 mRNA occurred in pepper leaves in response to wounding, high salinity and drought stress. These results suggest that bacterial pathogen infection, abiotic elicitors and some environmental stresses may play a significant role in signal transduction pathway for CADEF1 gene expression.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.79.2-80
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• 2003

To better understand plant defense responses against pathogen attack, we identified the transcription factor-encoding genes in the hot pepper Capsicum annuum that show altered expression patterns during the hypersensitive response raised by challenge with bacterial pathogens. One of these genes, Ca1244, was characterized further. This gene encodes a plant-specific Type IIIA - zinc finger protein that contains two Cys$_2$His$_2$zinc fingers. Ca1244 expression is rapidly and specifically induced when pepper plants are challenged with bacterial pathogens to which they are resistant. In contrast, challenge with a pathogen to which the plants are susceptible only generates weak Ca1244 expression. Ca1244 expression is also strongly induced in pepper leaves by the exogenous application of ethephon, an ethylene releasing compound. Whereas, salicylic acid and methyl jasmonate had moderate effects. Pepper protoplasts expressing a Ca1244-smGFP fusion protein showed Ca1244 localizes in the nucleus. Transgenic tobacco plants overexpressing Ca1244 driven by the CaMV 355 promoter show increased resistance to challenge with a tobacco-specific bacterial pathogen. These plants also showed constitutive upregulation of the expression of multiple defense-related genes. These observations provide the first evidence that an Type IIIA - zinc finger protein, Ca1244, plays a crucial role in the activation of the pathogen defense response in plants.