• Molecules and Cells
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• v.46 no.8
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• pp.513-525
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• 2023

Orange carotenoid protein (OCP) of photosynthetic cyanobacteria binds to ketocarotenoids noncovalently and absorbs excess light to protect the host organism from light-induced oxidative damage. Herein, we found that mutating valine 40 in the α3 helix of Gloeocapsa sp. PCC 7513 (GlOCP1) resulted in blue- or red-shifts of 6-20 nm in the absorption maxima of the lit forms. We analyzed the origins of absorption maxima shifts by integrating X-ray crystallography, homology modeling, molecular dynamics simulations, and hybrid quantum mechanics/molecular mechanics calculations. Our analysis suggested that the single residue mutations alter the polar environment surrounding the bound canthaxanthin, thereby modulating the degree of charge transfer in the photoexcited state of the chromophore. Our integrated investigations reveal the mechanism of color adaptation specific to OCPs and suggest a design principle for color-specific photoswitches.

• Journal of The Korean Society of Grassland and Forage Science
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• v.43 no.1
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• pp.22-27
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• 2023

This experiment was conducted to confirm the possibility of preparing Sorghum×sudangrass hybrid artificial hay using far-infrared rays in Korea. The machine used in this experiment is a drying device based on far-infrared rays, and is designed to control temperature, air flow rate, far-infrared radiation amount, and air flow speed. The Sorghum×sudangrass hybrids harvested in late September were wilted in the field for one day, and a drying test was performed on them. Conditions for drying were performed by selecting a total of 7 conditions, and each condition induced a change in radiation amount in a single condition (42%) and two steps (4 treatments) and three steps (2 treatments). The speed of the air flow in the device was fixed at 60 m/s, and the run time was changed to 30, 60, and 90 minutes. The average dry matter (DM) content was 82.84%. The DM content was 59.94 and 76.91%, respectively, in drying conditions 1 and 3, which were not suitable for hay. In terms of drying rate, it was significantly higher than 80% in the 5, 6 and 7 treatment, and power consumption was slightly high with an average of 5.7 kw/h. As for the feed value according to each drying condition, the crude protein (CP) content increased as the drying time increased, and there was no significant difference between treatments in ADF, NDF, IVDMD and TDN content. In terms of RFV, treatment 1, which is a single condition, was significantly lower than the complex condition. Through the above results, it was determined that the drying conditions 4 and 5 were the most advantageous when considering the drying speed, power consumption, and quality.

• Membrane Journal
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• v.22 no.2
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• pp.95-103
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• 2012

To treat nitrate and non-biodegradable organics effectively in sewage, industrial wastewater and livestock wastewater, the activated sludge process integrated by a membrane separation and a porous electrode- electrolysis was proposed and its efficiency was investigated. The proposed system was consisted of 3 processes; activated sludge, membrane filtration and electrolysis. In the study, the membrane filtration played a role in reducing the load of the electrolysis to operate the proposed process stably. The electrolysis consisted of a porous electrode to increase the efficiency due to the extension of the specific surface area. Additionally, redox reaction in the electrolysis was induced by decomposing influent water as current was applied. As a result, hydrogen free radicals and oxygen radicals as intermediates were produced and they acted as oxidants to play a role in decomposing non-degradable organics. It was environmentally-friendly process because intermediates produced by porous electrode were used to treat waste matters without supplying external reagent. Experimental data showed that the proposed process was more excellent than activated sludge process. SS removal efficiencies of the proposed process, membrane filtration and activated sludge process were about 100%, about 100% and about 90%, respectively. COD removal efficiencies of the proposed system, membrane filtration and activated sludge process were about 92%, about 84% and about 78%, respectively. T-N removal efficiencies of the proposed system, membrane filtration and activated sludge process were about 88%, about 67%, and about 58%, respectively. The SS data showed that SS was efficiently removed in the single of the membrane filtration. The COD/T-N data showed that COD/T-N of membrane hybrid process was treated by removing a little soluble organics and SS, and that COD/T-N of electrolysis hybrid process was treated by oxidize organics with high removal rate.

• BMB Reports
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• v.45 no.3
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• pp.183-188
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• 2012

Participates in actin remodeling through Rac and receptor endocytosis via Rab5. Here, we used yeast two-hybrid system with Eps8 as bait to screen a human brain cDNA library. ITSN2 was identified as the novel binding factor of Eps8. The interaction between ITSN2 and Eps8 was demonstrated by the in vivo co-immunoprecipitation and colocalization assays and the in vitro GST pull-down assays. Furthermore, we mapped the interaction domains to the region between amino acids 260-306 of Eps8 and the coiled-coil domain of ITSN2. In addition, protein stability assays and immunofluorescence analysis showed ITSN2 overexpression induced the degradation of Eps8 proteins, which was markedly alleviated with the lysosome inhibitor NH4Cl treatment. Taken together, our results suggested ITSN2 interacts with Eps8 and stimulates the degradation of Eps8 proteins.

• Journal of Plant Biotechnology
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• v.44 no.1
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• pp.61-68
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• 2017

Gibberellic Acid-Stimulated Arabidopsis (GASA) genes are involved in plant hormone signaling, cell division and elongation, as well as in responses to stress conditions in plants. In this study, we isolated a GASA gene from hybrid poplar (Populus alba ${\times}$ P. glandulosa) and analyzed its physiological phenotype and molecular functions in poplar. PagGASA cDNA encodes a putative protein composed of 95 amino acids containing an N-terminal signal peptide and a conservative cysteine-rich C-terminal domain. Southern blot analysis revealed that one or two copies of the PagGASA are present in the poplar genome. The PagGASA transcripts were highly detected in flowers and roots. Moreover, the expression of PagGASA was induced by growth hormone (gibberellic acid) and stress hormones (abscisic acid, jasmonic acid, and salicylic acid). By using transgenic analysis, we showed that the upregulation of PagGASA in poplar provides high tolerance to drought stress. Therefore, our results suggest that PagGASA plays an important role in drought stress tolerance via stress-related plant hormone signaling in poplar.

• Journal of Plant Biotechnology
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• v.44 no.1
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• pp.27-34
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• 2017

Our aim was to find the effective duration and culture conditions for microspore culture in a genetically variant cabbage (Brassica oleraceae L. var. capitata). We discovered that the '$2{\times}NLN$ medium containing $AgNO_3$ 1 mg/l, sucrose 13%' was most efficient in producing the cabbage embryos. The number of induced embryos was higher in $F_2$ or $F_3$ progeny generation than the $F_1$ hybrid cultivar used as plant materials. Thus, we recommend microspore culturing using progeny plants of failed $F_1$ cultivar. The acquisition ratio of embryos and plants derived from microspore was higher in the early flowering period as compared to the late flowering period. When transplanted in the soil, 71.2% plants developed from the early flowering period, compared to 27.0% from the middle period and 1.8% plants from the late period. Thus, we recommend microspore culture using buds collected during the early flowering period.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.2
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• pp.129-134
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• 2001

Since NNK is one of the most abundant tobacco-specific alkaloids and a strong carcinogenic nitrosamine, it has been used for evaluating a potential of carcinogenicity in the animal models. The present study has attempted to examine the potential of carcinogenicity of NNK in human epithelial cells, from which the cell type the most of cancers including oral cancer and nasal cavity cancer are originated. The cellular model used for the study is a human keratinocyte cell system immortalized by Ad12-SV40 hybrid virus. The cellular system has successfully been used for the carcinogenicity studies because of its limitless life span, epithelial morphology and nontumorigenicity. When cells were treated with a variety of NNK concentrations, levels of saturation density and soft agar colony formation were increased in a dose-dependent fashion. Colonies of large cell aggregates were above 5 at the higher doses. The results indicate that exposure of human cells with NNK induced loss of contact inhibition and increases of anchorage independence and cellular adhesion, which are typical characteristics of the neoplatically transformed cells. When cells were exposed with 100uM NNK for 2hr, mRNA levels of IL-1 and PAI-2 were increased in a dose-dependent manner, but expression of TGF- 1 was not affected. While expression of growth regulatory factors were altered with a short-term exposure, there was no alteration of these factors in the NNK-transformed cells. However, mRNA levels of fibronectin were increased both in the short-term treatment and in the transformation. The results suggest that altered expression of extracellular matrix such as fibronectin following short-term exposure might be fixed in the genome and these altered properties be continuously transfered throughout the cell division. Western blot analysis showed a translocation of PKC- from cytosolic fraction to the particulate fraction, indicating a possible role of NNK in the signal transduction pathway. The present study provided an evidence that NNK in the smoking may be associated with epithelial origin cancer such as oral and nasal cavity cancers. In addition, this study suggested that altered expression of extracellular matrix and PKC may play an important role in the carcinogenic mechanism of NNK.

• Journal of Plant Biotechnology
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• v.44 no.4
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• pp.409-415
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• 2017

The vegetation period of trees might be prolonged by the delay of the leaf senescence in autumn. Thus, we focused on the generation of senescence-delayed transgenic trees to enhance biomass production. The PagMYC2, a gene containing the basic helix-loop-helix domain, was selected as a candidate for a senescence-delayed transgenic tree. The PagMYC2 gene was specifically induced after treatment with phytohormone jasmonic acid, and upregulated by abiotic stresses such as salinity, osmotic pressure and a low temperature. The constitutive overexpression of the PagMYC2 delayed the leaf senescence and inhibited chlorophyll degradation in the transgenic poplars. Leaf senescence analysis was performed in the leaf tissues of the PagMYC2-over-expression transgenic poplars. The transgenic poplars exhibited higher photochemical efficiency than did a wild type plant under a short-day condition (6 hours light/18 hours darkness) or a low temperature condition ($15^{\circ}C$) that was similar to the weather conditions of autumn. These results suggest that the PagMYC2 is a useful genetic resource to improve biomass production, which is able to sustain growth with senescence-delayed leaves for a long time in autumn.

• The Korean Journal of Mycology
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• v.20 no.2
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• pp.118-125
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• 1992

Interspecific fusion products were obtained by protoplast fusion induced by polyethylene glycol, from auxotrophic mutants, Pleurotus cornucopiae and P. florida. The fusants were classified into allodiploidy, stable heterokaryon, and spontaneously segregated heterokaryons. Fruiting body of the clamped or clampless fusants was produced by light-dark cycle on the sawdust medium in glass bottles. Most of these clampless fusants produced mature basidiocarps. The pilei showed various mixed colors resembling the parents. All fruit bodies presented clamp connections except two fusants. When small tissues of stipe from basidiocarps were cultured on a complete medium, mycelial colonies grew more vigorously than that of the original clampless fusants. Five fusants in three crosses were analysed with the distribution of progenies and segregation of genetic characters by random spore analyses. The genetic markers were shown to segregate and recombine in the first generation of monospores isolated from basidiocarps. The analysis indicated the heter-okar-yosis and strong evidence for haploidy of vegetative nuclei, a sexual cycle consisting of nuclear fusion and meiosis. Genotypes of a large number of auxotiophic progenies were not detected. The aberration ratio of segregants indicated the gene interaction resulting from different genome structure between vegetatively incompatible species.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.172-172
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• 2017

Pollen germination and its' viability in bellflower hybrid system are of great importance. The present study was conducted to investigate the several factors underlying the pollen germination of Platycodon grandiflorum and obtain the basic data for effective artificial pollination for the production of sound specifies. The pollens of Platycodon grandiflorum started germination from one hour after planting, and the germination was actively progressed as time dependent manner. For lighting conditions, the germination of pollens under the light was faster by more than twice than that without the light. Furthermore, the germination was better in the high temperature rather than in the low temperature. The germination rate was higher in the $30^{\circ}C$. For the carbon source, the germination rate was better at the concentration of 15% regardless of the kinds. In particular, the highest value was observed with glucose. The germination rate was decreased substantially as the increasing with the higher pH. The dynamic germination of pollens was observed at the pH 5. With respect to the growth regulator, the higher concentration of NAA induced the higher the germination rate. $GA_3$ showed a good germination rate in $0.05mg{\cdot}L^{-1}$. Meanwhile, for kinetin, lower concentration increased the germination rate, unlike NAA. The higher concentrations of boric acid degraded the germination rate, and the addition of boric acid of $10mg{\cdot}L^{-1}$ demonstrated higher germination rate than the addition of other growth regulators. Notably, the addition of asparaginic acid exhibited the similar results in all test sectors regardless of concentration, whereas a little higher result was observed in the high concentration sector. Taken together, the results concluded that the boric acid was considered as one of the essential minerals that played an important role on the germination of pollens.