• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.3
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• pp.190-195
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• 2020

Cadmium (Cd) toxicity is a serious limitation for agricultural production. In this study, we explored tolerance mechanism associated with Cd toxicity tolerance in alfalfa plants. We used three distinct alfalfa cultivars M. sativa cv. Vernal, M. sativa cv. Zhung Mu, and M. sativa cv. Xing Jiang Daye in this study. Cd showed declined chlorophyll score in Xing Jiang Daye compared with Zhung Mu and Vernal. No significant change observed among the cultivars for root and shoot length. Atomic absorption spectroscopy analysis demonstrated a significant accumulation of Cd, Fe, S and PC in distinct alfalfa cultivars. However, Zhung Mu and Xing Jiang Daye declined Cd accumulation in root, where Fe, S and PC incremented only in Zhung Mu. It suggests that excess Cd in Zhung Mu possibly inhibited in root by the increased accumulation of Fe, S and PC. This was further confirmed by the response of Fe (MsIRT1) and S transporters (MsSULTR1;2 and MsSULTR1;3), and MsPCS1 genes associated with Fe, S and PC availability and translocation in roots and shoots. It suggests that specially the transcript signal inducing the responses to adjust Cd especially in Zhung Mu. This finding provides the essential background for further molecular breeding program for forage crops.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.216-216
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• 2005

• Journal of Life Science
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• v.19 no.12
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• pp.1685-1689
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• 2009

Phytochelatins (PCs) are small polypeptides synthesized by PC synthase (PCS). They are present in various living organisms including plants, fission yeast, and some animals. The presumed function of PCs is the sequestration of cytosolic toxic heavy metals like cadmium (Cd) into the vacuoles via vacuolar membrane localized heavy metal tolerance factor 1 (HMT-1). HMT-1 was first identified in fission yeast (SpHMT-1), and later in Caenorhabdtis (CeHMT-1). Recently, its homolog has also been found in PC-deficient Drosophila (DmHMT-1), and this homolog has been shown to be involved in Cd detoxification, as confirmed by the heterologous expression of DmHMT-1 in fission yeast. Therefore, the dependence of HMT-1 on PC in Cd detoxification should be re-evaluated. I heterologously expressed SpHMT-1 in cytosolic PC-deficient yeast, Saccharomycea cerevisiae, to understand the dependence of HMT-1 on PC. Yeast cells expressing SpHMT-1 showed increased tolerance to Cd compared with control cells. This result indicates that SpHMT-1 is not strictly correlated with PC production on its function. Moreover, yeast cells expressing SpHMT-1 showed increased tolerance to exogenously applied glutathione (GSH) compared with control cells, and the tolerance to Cd was further increased by exogenously applied GSH, while tolerance in control cells was not. These results indicate that the function of SpHMT-1 in Cd detoxification does not depend on PCs only, and suggest that SpHMT-1 may sequester cytosolic GSH-Cd complexes into the vacuole.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.72.2-73
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• 2003

We found a soybean (Glycine max) cultivar 561 that was strongly resistant to a virulent bacterial strain of a Pseudomonas spp. Further identification revealed that the Pseudomonas spp. was a strain of Pseudomonas aeruginosa. Furthermore we identified specific genes involved in the resistance of soybean 561 and analyzed the pattern of gene expression against the Pseudomonas infection using differential-display reverse transcription PCR (DDRT-PCR). More than 126 cDNA fragments representing mRNAs were induced within 48 hours of bacteria inoculation. Among them, 28 cDNA fragments were cloned and sequenced. Twelve differentially displayed clones with open reading frames had unknown functions. Sixteen selected cDNA clones were homologous to known genes in the other organisms. Some of the identified cDNAs were pathogenesis-related genes (PR genes) and PR-like genes. These cDNAs included a putative calmodulin-binding protein, an endo-1,3-1,4-b-D-glucanase, a b-1,3-endoglucanase, a b-1,3-exoglucanase, a phytochelatin synthetase-like gene, a thiol pretense, a cycloartenol synthase, and a putative receptor-like sorineithreonine protein kinase. Among them, we found that four genes were putative pathogenesis-related genes (PR) induced significantly by the p. aeruginosa infection. These included a calmodulin-binding protein gene, a b-1,3-endoglucanase gene, a receptor-like sorine/threonine protein kinase gene, and pS321 (unknown function). These results suggest that the differentially expressed genes may mediate the strong resistance of soybean 561 to Pseudomonas aeruoginosa.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.235-235
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• 2017

Chromium (Cr) toxicity is hazardous to the seed germination, growth, and development of plants. ${\gamma}$-Aminobutyric acid (GABA) is a non-protein amino acid and is involved in stress tolerance in plants. To investigate the effects of GABA in alleviating Cr toxicity, we treated eight-d-old mustard (Brassica juncea L.) seedlings with Cr (0.15 mM and 0.3 mM $K_2CrO_4$, 5 days) alone and in combination with GABA ($125{\mu}M$) in a semi-hydroponic medium. The roots and shoots of the seedlings accumulated Cr in a dose-dependent manner, which led to an increase in oxidative damage [lipid peroxidation; hydrogen peroxide ($H_2O_2$) content; superoxide ($O{_2}^{{\cdot}-}$) generation; lipoxygenase (LOX) activity], MG content, and disrupted antioxidant defense and glyoxalase systems. Chromium stress also reduced growth, leaf relative water content (RWC), and chlorophyll (chl) content but increased phytochelatin (PC) and proline (Pro) content. Furthermore, supplementing the Cr-treated seedlings with GABA reduced Cr uptake and upregulated the non-enzymatic antioxidants (ascorbate, AsA; glutathione, GSH) and the activities of the enzymatic antioxidants including ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione peroxidase (GPX), superoxide dismutase (SOD), catalase (CAT), glyoxalase I (Gly I), and glyoxalase II (Gly II), and finally reduced oxidative damage. Adding GABA also increased leaf RWC and chl content, decreased Pro and PC content, and restored plant growth. These findings shed light on the effect of GABA in improving the physiological mechanisms of mustard seedlings in response to Cr stress.

• The Plant Pathology Journal
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• v.19 no.5
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• pp.239-247
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• 2003

In Korea, a local soybean (Glycine max) genotype 56l. was found to be strongly resistant to a virulent bacterial strain of a Pseudomonas sp. SN239. Specific genes involved in the resistance of the soybean genotype 561 were identified and the pattern of gene expression against the Pseudomonas infection was analyzed using differential-display reverse transcription PCR (DDRT-PCR). More than 126 cDNA fragments representing mRNAs were induced within 48 hours of bacteria inoculation. Among them, 28 cDNA fragments were cloned and sequenced. Twelve differentially displayed clones with open reading frames had unknown functions. Sixteen selected cDNA clones were homologous to known genes of other organisms. Some of the identified cDNAs were pathogenesis-related (PR) genes and PR-like genes. These cDNAs included a putative calmodulin-binding protein; an endo-l,3-1,4-$\bate$-D-glucanase; a $\bate$-1,3-endoglucanase; a $\bate$-1,3-exoglucanase; a phytochelatin synthetase-like gene; a thiol protease; a cycloartenol synthase; and a putative receptor-like serine/threonine protein kinase. Among them, four genes were found to be putative PR genes induced significantly by the Pseudomonas infection. These included a calmodulin-binding protein gene, a $\bate$-1,3-endoglucanase gene, a receptor-like serine/threonine protein kinase gene, and pS321 (unknown function). These results suggest that the differentially expressed genes may mediate the strong resistance of soybean 561 to the strain SN239 of Pseudomonas sp.

• Applied Biological Chemistry
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• v.39 no.6
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• pp.494-500
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• 1996

Uptake of hen metal ions by water dropwort (Oenanthe stolonifera DC.) and its cadmium-binding protein were studied to probe for good method to remove heavy metal contaminants from environments. The plant was cultured in the culture medium (pH 7.0) containing the various concentrations of $Cd^{2+}$, $Cr^{3+}$ or $Pb^{2+}$, for 3 and 7 days. The residual heavy metals deposited in roots linearly increased as the metal ions concentration increased up to 17 ppm for $Cd^{2+}$, 20 ppm for $Cr^{3+}$ and 50 ppm for $Pb^{2+}$. Above these concentrations, the plant growth was inhibited and the uptake rates of the metal ions decreased. The heavy metals absorbed by the plant were mostly deposited in roots. In particular, the residual concentration of lead in roots was about four times higher than those of cadmium and chromium. When cultured in the medium containing 20 ppm of each metal ion, 80% of cadmium, 90% of cromium and 96% of lead were deposited in roots out of the total residual metal ions in the plant. These values correspond to 6.1 mg of cadmium, 5.2 mg of chromium and 23.6 mg of lead per one gram of roots tissue on a dry weight basis. A cadmium-binding protein was partially purified by extraction, gel filtration and DEAE-Cellulose chromatography from water dropworts that was grown in the medium containing 20 ppm $Cd^{2+}$. The purified protein was a single band on SDS- and non-denaturing- polyacrylamide gel electrophoresis. Its molecular mass was estimated to be ca. 5,000 dalton by gel filteration. Analysis of amino acid composition of the protein indicated that it had a typical amino acid composition of heavy metal-binding protein in that it contained 27% of acidic amino acids and 9.9% of cysteine. However, it is likely that the protein is a new plant metal-binding protein, since its amino acid composition is somewhat different from those of phytochelatins that have been known so far.