• Journal of Plant Biology
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• v.38 no.3
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• pp.235-242
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• 1995

Effects of methyl jasmonate (MeJA) on ethylene production in tomato(Lycopersicon esculentum Mill.) hypocotyl segments and fruits were studied. Ethylene production in tomato hypocotyl segments was inhibited by the increasing concentratons of MeJA, and 450 $\mu$M of MeJA showed 50% inhibitory effect. Time course data indicate that this inhibitory effect of MeJA appeared after 3 h of incubation period and continued until 24 h. Inhibition of ethylene producton by MeJA was due to the decrease in 1-aminocyclopropane-1-carboxylic acid(ACC) synthase activity. However, MeJA treatment had no effect on ACC oxidase activity and the accumulaton of ACC oxidase mRNAs. MeJA also inhibited auxin-induced ethylene production by decreasing in ACC synthase activity. In contrast, MeJA stimulated ethylene production in tomato fruits. When 30 $\mu$L/mL MeJA was treated in a gaseous state, ethylene production doubled and this stimulating effect continued until 4 days. To investigate the mechanisms of MeJA on ethylene production, ACC synthase and ACC oxidase activities were examined after MeJA treatment. MeJA increased the activities of both ACC synthase and ACC oxidase, and induced ACC oxidase mRNA accumulation. These data suggest that MeJA plays distinct roles in the ethylene production in different tomato tissues. It is possible that MeJA affects differently the mechanisms of signal transuction leading to the ethylene biosynthesis.

• Journal of Plant Biotechnology
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• v.42 no.3
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• pp.265-270
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• 2015

The roots of Codonopsis lanceolata (Campanulaceae) contain several kinds of triterpenoid saponin with high medicinal values, which have been used in traditional medicines. This study investigates the impacts of methyl jasmonate (MeJA) - adding time on the saponin synthesis and the hairy root growth of C. lanceolata. A significant decrease in major saponin (lancemaside of three kinds) content of hairy roots was observed with MeJA treatments. Contents of lancemaside A, B and E decreased about 15% more than non-treated hairy roots. In contrast, minor saponin (foetidissimoside A and aster saponin Hb) accumulation was about 15% higher than the non-treated hairy roots. These results suggest that MeJA treatment could be used in the production of teriterpene saponins.

• Journal of Plant Biology
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• v.37 no.4
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• pp.445-452
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• 1994

Effects of methyl jasmonate (MeJA) on ethylene production in mungbean (Phaseolus radiatus L.) hypocotyl and leaf segments were studied. Ethylene production in mungbean hypocotyl segments was decreased in proportion to MeJA concentrations and $450\;\mu\textrm{M}$ of MeJA showed 50% inhibitory effect. This inhibitory effect appeared after 3 h of incubation period and continued for 24 h. Inhibition of ethylene production by MeJA was due to the decrease in 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase activity. However, MeJA treatment had no effect on ACC content and ACC synthase activity. MeJA also inhibited auxin-induced ethylene production in hypocotyls. To investigate the mechanisms of the inhibitory effect of MeJA on the auxin-induced ethylene production, ACC synthase and ACC oxidase activity were examined after MeJA treatment. MeJA decreased the ACC content and ACC synthase activity as weD as ACC oxidase activity in the auxin-treated tissue. These results suggest that the inhibition of MeJA on auxin-induced ethylene production is not due to the direct inhibitory effect of MeJA on the ACC synthase, but to the inhibition of the ability of IAA to promote the synthesis of ACC synthase. In contrast, ethylene production from the detached mungbean leaves was stimulated by MeJA. The rate of ethylene production increased approximately 65% over the control after 12 h of incubation period by $4.5\;\mu\textrm{M}$ MeJA. When MeJA was applied to detached leaves along with IAA, the effect of MeJA appeared to be additive. In an effort to elucidate mechanisms of MeJA action on auxin-induced ethylene production in the leaf tissue, enzyme activities of ACC synthase and ACC oxidase were examined. MeJA stimulated ACC oxidase activity but did not affect ACC synthase activity in leaf tissue. Together, these results suggest that MeJA plays different roles in the ethylene production in the different mungbean tissues.issues.

• Animal cells and systems
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• v.7 no.4
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• pp.337-343
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• 2003

Methyl jasmonate (MeJA) is a signal molecule in the activation of defense responses in plants. In this study, we isolated 15 MeJA-inducible genes by subtractive hybridization. These genes encode two myrosinase-binding proteins, five lipase-like proteins, a polygalacturonase inhibitor, a putative chlorophyll-associated protein, a terpene synthase, a dehydroascorbate reductase, an ascorbate oxidase, a cysteine protease, an O-methyltransferase, and an epithiospecifier protein. Northern analysis showed that most of the Chinese cabbage genes are barely expressed in healthy leaves, but are strongly induced by MeJA treatment. We also examined whether these MeJA-inducible genes were activated by ethethon, BTH, and Pseudomonas syringae pv. tomato (Pst), a nonhost pathogen of Chinese cabbage. The results showed that none of the MeJA-inducible genes was strongly induced by ethephon or by BTH. The genes encoding lipase-like proteins and a myrosinase-binding protein were weakly induced by Pst. Other MeJA-inducible genes were not activated at all by the pathogen.

• Journal of Plant Biotechnology
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• v.40 no.3
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• pp.178-183
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• 2013

Traditionally, Codonopsis lanceolata root have been used as a source of natural heath food. This study was initiated to investigate the impacts of methyl jasmonate (MeJA) and salicylic acid (SA) on adventitious growth C. lanceolata, the production of secondary metabolites, such as flavonoids, total phenolic compound, antioxidative activity (DPPH). The highest phenolics content was observed in treatment of 20 uM MeJA (74.53 mg/g). The content of total flavonoids followed the similar pattern as that of total phenolics, showing 38.45 mg/g of C. lanceolata treated by 20 uM MeJA. The DPPH scavenging activity was 24.2 ($IC_{50}$) of C. lanceolata treated by 20 uM MeJA. These results provide useful information for enhancing biological properties of cultural roots of C. lanceolata.

• Journal of Plant Biotechnology
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• v.31 no.1
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• pp.79-82
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• 2004

The effect of abscisic acid (ABA) and methyl jasmonate (MeJA) on bulblet formation from the culture of Allium victorialis var. platyphyllum Makino was studied. Shoot clumps were cultured on MS medium containing ABA (0, 0.01∼2.0mg/L) and MeJA (0.01∼5.0mg/L). ABA at low concentrations (0.01mg/L) induced shoot proliferation without bulblet formation. However, bulblet formation started on the medium containing MeJA approximately in 4-6 weeks of culture. Furthermore, 1.0mg/L MeJA resulted in bulblet formation at high frequency (100％) as compare to the control (46.1％). Cortical cells of the bulblets enlarged on medium with MeJA had dense protein-like substance in expanded and round cells when examined under the microscope. The data described here show that formation and enlargement of bulblets from Allium victorialis can be improved by addition of appropriate concentration of MeJA.

• Journal of Life Science
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• v.25 no.1
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• pp.37-43
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• 2015

We have investigated the effects of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), indole-3-acetic acid (IAA) and methyl jasmonate (MeJA) on the development of aerenchyma in the primary root of maize (Zea mays). Because plant hormones affected the longitudinal organization of the primary root, we need an indicator to direct the positions for comparison between control and hormone-treated roots. Therefore, the zones of the maize primary root were categorized as PR25, PR50 and PR75, where each value indicates the relative position between the root tip (PR0) and the base (PR100). Aerenchyma was not observed at PR25 and PR50 and rarely found at PR75 in the cortex of control roots. The aerenchymal area at PR75 increased in the presence of the ethylene precursor ACC or a natural auxin IAA. On the other hand, MeJA differentially acted on non-submerged and submerged roots. Exogenously applied MeJA suppressed the aerenchyma formation in non-submerged roots. When the primary root was submerged, aerenchymal area expanded prominently. The submergence-induced aerenchyma formation was amplified with MeJA. Lateral root primordia have been known to inhibit aerenchymal death of surrounding cells. All the three hormones stimulating aerenchyma formation as described above did not restore the inhibition caused by lateral root primordia, suggesting that the inhibitory step regulated by lateral root primordia can be located after hormonal signaling steps.

• Journal of Plant Biotechnology
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• v.32 no.3
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• pp.225-231
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• 2005

This study was initiated to investigate the impacts of methyl jasmonate (MeJA) on adventitious root growth of Panax ginseng, the production of secondary metabolites, such as ginsenosides and phenolic compounds, and antioxidative activity. Among various concentrations of MeJA, $100\;{\mu}M$ MeJA increased the ginsenosides accumulation to 26.6 mg/g dry wt, about 8 times higher than the control in ginseng adventitious roots (GAR). In addition, $50\;{\mu}M$ MeJA increased the accumulation of phenolic compounds to 0.38 mg/g dry wt, about 3 times higher than control in GAR. This MeJA treatment was more effective in conditioned medium (CM) which obtained in bioreactor after 40 days of culture than in fresh medium (FM). Treatment of $100\;{\mu}M$ MeJA in CM increased the accumulation of ginsenosides (1.7 times) and phenolic compounds (1.2 times) more than in FM, respectively. Consequently, these high accumulation of ginsenosides and phenolic compounds by MeJA led to increase the antioxidative activities expressed to the DPPH scavenging activity (over $78.3\%$). The DPPH scavenging activity in control was $45.5\%$.

• Plant Biotechnology Reports
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• v.5 no.1
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• pp.27-34
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• 2011

Jasmonates control diverse plant developmental processes, such as seed germination, flower, fruit and seed development, senescence and tuberization in potato. To understand the role of methyl jasmonate (MeJA) in potato tuberization, the Arabidopsis JMT gene encoding jasmonic acid carboxyl methyltransferase was constitutively overexpressed in transgenic potato plants. Increases in tuber yield and size as well as in vitro tuberization frequency were observed in transgenic plants. These were correlated with JMT mRNA level-- the higher expression level, the higher the tuber yield and size. The levels of jasmonic acid (JA), MeJA and tuberonic acid (TA) were also higher than those in control plants. Transgenic plants also exhibited higher expression of jasmonate-responsive genes such as those for allene oxide cyclase (AOC) and proteinase inhibitor II (PINII). These results indicate that JMT overexpression induces jasmonate biosynthesis genes and thus JA and TA pools in transgenic potatoes. This results in enhanced tuber yield and size in transgenic potato plants.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2023.04a
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• pp.53-53
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• 2023

Abeliophyllum distichum, one of the Korean endemic plant, is a significant pharmaceutical plant resource. A. distichum with phenylethanoid glycoside can use to regulate the development of cancer, DNA damage with radicals, and the generation of inflammatory mediators. In this study, we investigated whether the biomass, content of phenylethanoid glycoside, and growth rate of callus derived from A. distichum (cultivar Okhwang1, CAD) change in the absence or presence of plant hormones (2,4-Dichlorophenoxyacetic acid; 2, 4-D and 1-Naphthaleneacetic acid; NAA). The results showed that the best biomass, the growth rate of callus, and the contents of phenylethanoid glycoside were cultivated on Murashige and Skoog (MS) growth medium fortified with 1 ppm 2,4-D + 2 ppm NAA after 4 weeks. In a further study, CAD was cultivated on MS growth medium fortified with an elicitor (Methyl Jasmonate, MeJA). The results showed that CAD turned to brown color and fragile form with the elicitor. HPLC-PDA analysis revealed that the contents of phenylethanoid glycoside in the elicitor-treated group were higher than in the elicitor-non-treated group. These results are consistent with the findings of Arano-Varela H et al.,'s study which is that acteoside production can increase after the treatment of MeJA. Therefore, this study can be used to develop an effective and sustainable production of useful substances as an alternative to plant cultivation.