• BMB Reports
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• v.57 no.2
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• pp.79-85
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• 2024

Pre-harvest sprouting is a critical phenomenon involving germination of seeds in the mother plant before harvest under relative humid conditions and reduced dormancy. In this paper, we generated HDR mutant lines with one region SNP (C/T) and an insertion of 6 bp (GGT/GGTGGCGGC) in OsERF1 genes for pre-harvest sprouting (PHS) resistance using CRISPR/Cas9 and a geminiviral replicon system. The incidence of HDR was 2.6% in transformed calli. T₁ seeds were harvested from 12 HDR-induced calli and named ERF1-hdr line. Molecular stability, key agronomic properties, physiological properties, and biochemical properties of target genes in the ERF1-hdr line were investigated for three years. The ERF1-hdr line showed significantly enhanced seed dormancy and pre-harvest sprouting resistance. qRT-PCR analysis suggested that enhanced ABA signaling resulted in a stronger phenotype of PHS resistance. These results indicate that efficient HDR can be achieved through SNP/InDel replacement using a single and modular configuration applicable to different rice targets and other crops. This work demonstrates the potential to replace all genes with elite alleles within one generation and greatly expands our ability to improve agriculturally important traits.

• Journal of Plant Biology
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• v.35 no.2
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• pp.165-171
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• 1992

In order to study regulation of rbcL gene expression, rbcL gene of chloroplast DNA (Cp DNA) from maize was cloned. Cp DNA was isolated from intact chloroplast and digested with BamHI. BamHI 9 fragment of Cp DNA containing rbcL gene was ligated to pUC19 and transformed into E. coli DH5a. This recombinant plasmid was named pRLYSl. pRLYSl was hybridized with a part of rbcL gene from rice and digested with restriction enzyme BamHI, HindIIl, and PstI. From these results, it was confirmed that pRLYS1 contains intact rbcL gene and orientation of BamHI 9 fragment of Cp DNA in pRLYS1 was determined.rmined.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.2
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• pp.154-159
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• 2006

Interleukin-18 (IL-18), otherwise known as interferon-gamma-inducing factor (IGIF), is one of several well characterized and important cytokines that contribute to host defenses. The complementary DNA (cDNA) of mature human interleukin-18 gene (hIL-18) was fused with the signal peptide of the rice amylase 1A gene (Ramy1A) and introduced into the plant expression vector under the control of a duplicated CaMV 35S promoter. The recombinant plasmid was transformed into tobacco (Nicotiana tabacum L. cv Havana) using the Agrobacterium-mediated transformation method. The integration of the hlL-18 gene into the genome of transgenic tobacco plants was confirmed by polymerase chain reaction (PCR) amplification and its expression was observed in the suspension cells that were derived from the transgenic plant callus by using Northern blot analysis. The hlL-18 protein was detected in the extracts of the transgenic callus and in the medium of the transgenic tobacco suspension culture by using immunoblot analysis. Based upon enzyme-linked immunosorbant assay (ELISA) results, the expression level of the hlL-18 protein approximated $166{\mu}g/L$ in the suspension culture medium. Bioassay results from the induction of $interferon-{\gamma}$ from a KG-1 cell line indicated that the hlL-18 secreted into the suspension culture medium was bioactive.

• International Journal of Automotive Technology
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• v.7 no.6
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• pp.653-658
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• 2006

The enormous increase in the use of fossil energy sources throughout the world has caused severe air pollution and a depletion of energy. Besides, it seems very difficult to comply with the upcoming stringent emission standards in vehicles. In order to develop low emission engines, research on better qualified fuels as alternative fuels to secure high engine performance becomes a more important issue than ever. Since sulfur contained in diesel fuel is transformed in sulfate-laden particulate matters when a catalyst is applied, it is necessary to provide low sulfur fuels before any Pt-based oxidation catalysts are applied. But the excessive reduction of sulfur levels may cause the lubricity of fuel and engine performance to degrade. In this aspect, biodiesel fuel derived from rice bran is applied to compensate viscosity lost in the desulfurization treatment. This research is focused on the performance of an 11,000cc diesel engine and the emission characteristics by the introduction of ULSD(Ultra Low Sulfur Diesel), BD20(Diesel 80%+Biodiesel 20%) and a diesel oxidation catalyst, where BD20 is used to improve the lubricity of fuel in fuel injection systems as fuel additives or alternative fuels.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.3
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• pp.264-272
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• 2011

It needs to develop high phosphate-available rice that is able to minimize environmental pollution caused by phosphate fertilizer. Then we have transformed 4 rice transporter genes, OsPT(Oryza sativa Phosphate Transporter)1, OsPT4, OsPT7 or OsPT8, to rice (Oryza sativa cv. Dongjin) via Agrobacterium-mediated transformation. We tested adaptation in the P-deficient condition of Dongjin (parental) and each transgenic line in the pot and the field conditions. Definite physiological changes have been observed in OsPTs transgenic lines including culm length, root formation and heading date. Phosphate uptake at harvesting stage was about three times higher in OsPT1-OX (overexpression) and OsPT4-OX than in Dongjin (wt) without P application. There are no variations in total phosphate-content of brown rice of OsPT1-OX in spite of high phosphate uptake. Practically the expression of OsPT1 has contributed to stabilize grain production without P fertilization in rice cultivation than Dongjin.

• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.37-42
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• 2013

Rice is one of the most important cereal crops as a model plant for functional genomics of monocotyledons and usually transformed using Agrobacterium tumefaciens. However, the transformation's process using previous method is still time consuming and uneconomical, low efficiency. In this study, we established a new method by modifying the general Agrobacterium protocol especially in the infection and co-cultivation, Agrobacterium elimination, infected calli's selection steps using liquid media. We directly inoculated Agrobacterium containing a ZjLsL gene under the control of constitutive promoter into the 1- to 3-week-old rice calli derived from mature seeds. After 3 days of co-cultivation, the infected calli were transferred onto liquid media of Agrobacterium elimination and calli's selection for 3 days. The calli were transferred to calli's growth solid media for 14 days and then the calli transferred to shoot induction and root induction media. Putative transformants were initially selected on the medium containing phosphinothricin, and the PAT protein verified by PAT strip test. This method in this study would lead to reduction of substantial labor and time to generate transgenic plants.

• Korean Journal of Weed Science
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• v.18 no.2
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• pp.161-170
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• 1998

Antagonistic mode of action of fenoxaprop-P-ethyl [ethyl(R)2-4-{(6-chloro-2-benzoxazolyloxy) phenoxy}propionate] with bentazon was investigated with respect to absorption, translocation, metabolism, and change in target site response of fenoxaprop-P-ethyl using four-leaf stage of rice(Oryza sativa L.) and barnyardgrass [Echinochloa eras-galli (L.) P. Beauv.]. Shoots of rice and barnyardgrass was more sensitive to fenoxaprop-P-ethyl than the roots. More than 90% of fenoxaprop-P-ethyl was absorbed within 6 hours after treatment and 30% of the absorbed was acropetally and basipetally translocated at 24 hours after treatment. Fenoxaprop-P-ethyl was rapidly transformed to its acid form, fenoxaprop(2-[4-(6-chloro-2-benzoxazolyloxy)phenoxy]propionic acid), which was subsequently metabolized to polar conjugates. However, changes in absorption, translocation, and metabolism of fenoxaprop-P-ethyl by bentazon treatment were not found in both species. Background activity of acetyl-CoA carboxylase(ACCase) in rice and barnyardgrass was 26.5 and 23.2nmol/min/mg, respectively. Concentration required to inhibit fifty percent enzyme activity$(I_{50})$ in vitro was 6.5~7.4${\mu}M$ of fenoxaprop-P-ethyl and more than 500${\mu}M$ of bentazon. There were no significant differences in $I_{50}$ value between two treatments of fenoxaprop-P-ethyl alone and its bentazon mixture. However, bentazon reduced ACCase activity in vivo and inhibited electron transport in chloroplast thylakoid. Based on the results obtained, it is concluded that the antagonistic effect of bentazon occurs due not to direct effect on target site of fenoxaprop-P-ethyl, but to indirect involvement in reducing herbicidal activity of fenoxaprop-P-ethyl through physiological disturbances caused by bentazone at whole chloroplast level.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.3
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• pp.132-141
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• 2012

Climate change impact assessment of cereal crop production in South Korea was performed using land attributes and daily weather data at a farm scale as inputs to crop models. Farmlands in South Korea were grouped into 68 crop-simulation zone units (CZU) based on major mountains and rivers as well as existing land use information. Daily weather data at a 1-km grid spacing under the A1B- and RCP8.5 scenarios were generated stochastically to obtain decadal mean of daily data. These data were registered to the farmland grid cells and spatially averaged to represent climate conditions in each CZU. Monthly climate data for each decade in 2001~2100 were transformed to 30 sets of daily weather data for each CZU by using a stochastic weather generator. Soil data and crop management information for 68 CZU were used as inputs to the CERES-rice, CERE-barley and CROPGRO-soybean models calibrated to represent the genetic features of major domestic cultivars in South Korea. Results from the models suggested that the heading or flowering of rice, winter barley and soybean could be accelerated in the future. The grain-fill period of winter barley could be extended, resulting in much higher yield of winter barley in most CZUs than that of rice. Among the three major cereal grain crops in Korea, rice seems most vulnerable to negative impact of climate change, while little impact of climate change is expected on soybeans. Because a positive effect of climate change is projected for winter barley, policy in agricultural production should pay more attention to facilitate winter barley production as an adaptation strategy for the national food security.

• Korean Journal of Environmental Agriculture
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• v.15 no.2
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• pp.167-178
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• 1996

In order to identify PCP glucose conjugates transformed from PCP in soybean and rice cell suspension cultures, the purified metabolites were acetylated, purified twice by HPLC using a normal and a reversed phase column, and then subjected to fast atom bombardment(FAB) mass spectrometric analysis. As were the conjugates, their acetylated derivatives of the glucose conjugates formed at the early stage(48 hr) of metabolism were separated by HPLC into three fractions. FABMS analysis of each fraction revealed that, at least in two fractions, the locations of the spectral peaks were practically coincident with those deducible from the structures of pentachlorophenyl and tetrachlorophenyl ${\beta}-D-glucopyranosides$. Based on information obtained from mass spectral and chromatographic analysis of not only the water-soluble metabolites but also aglycones and glycone, it is concluded that PCP is primarily metabolized to glucose conjugates, which account for more than 50% recovery of the PCP-conveyed radioactivity from the water soluble metabolites : The conjugates are mainly made up of pentachlorophenyl ${\beta}-D-glucopyranoside$, tetrachlorophenyl ${\beta}-D-glucopyranosides$( probably 2 or more isomers), and 2-hydroxy-3,4,5,6-tetrachlorophenyl ${\beta}-D-glucopyranoside$.

• Journal of the Korean association of regional geographers
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• v.11 no.2
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• pp.278-290
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• 2005

This study deals with the geomorphic, environmental and land use changes by comparative analysis using Landsat TM images of 1988 year and ETM ones of 2002 year, partly together with the new Quick Bird images having 60cm resolution for more detail analysis, focusing on the Oncheon gun(county) in Pyeongnam Province, west coast zone of North Korea. The main analysis methodology is neural network classification, which is more advanced techniques for the classification of land cover and land use, with higher accuracy rate and lower errors. The TM images of 1988 year show, mainly, the on-construction tide embank for the reclamation at Gwangryangman bay and salt farm on the reclaimed tidal flat. But, ETM images of 2002 year present stabilized reclaimed land, salt farm and rice field, recently transformed from salt farm. Especially, new tidal land has been naturally developed on the coastal shallow out of tide embank and salt farm. The results of the study may help to database coastal environmental changes and to support for reasonable and productive land use of North Korea, and to manage and plan unified national land in the near future.