• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.248.2-248
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• 1995

No Abstract, See Full Text

• Proceedings of the Korea Crystallographic Association Conference
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• 2002.11a
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• pp.25-25
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• 2002

CodWX, encoded by the cod operon in Bacillus subtilis, is a member of the ATP-dependent protease complex family, and is homologous to the eukaryotic 26S proteasome. It consists of two multimeric complexes: two hexameric ATPase caps of CodX and a protease chamber consisting of CodW dodecamer. Prior structural studies have shown that the N-terminal threonine residue is solely functional as a proteolytic nucleophile in ATP-dependent proteases such as HslV and certain β-type subunits of 20S proteasome, which have a primary sequence similarity of -50% and -20% with CodW respectively. Here we present a 3.0 Å resolution crystal structure of CodW, which is the first N-terminal serine protease among the known proteolytic enzymes. In spite of the same fold and the conserved contacts between subunits with HslV in E. coli and H. influenza, this structure shows the five additional residues extending from conserved Thr1 among the other ATP-dependent pretense and extraordinary basic proteolytic chamber.

• Plant Biotechnology Reports
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• v.3 no.3
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• pp.225-241
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• 2009

We investigated the transcriptional profiles of Japanese indigenous grape cultivar 'Koshu' (Vitis vinifera) leaf and berry skin during ripening. In leaf, 64 genes were abundantly transcribed at the end of $v{\acute{e}}raison$ (14 weeks post-flowering), whereas the expression of 61 genes was upregulated at the end of ripening (20 weeks post-flowering). In berry skin, 67 genes were abundantly transcribed at the end of $v{\acute{e}}raison$, whereas the expression of 86 genes was upregulated at the end of ripening. Gene expression associated with biological processes was activated in both tissues at the end of ripening. The expression of genes associated with photosynthesis, sugar synthesis, anthocyanin synthesis, cinnamic acid synthesis, and amino acid metabolism was observed in leaf and berry skin during ripening, together with the accumulation of sugars, anthocyanins, cinnamic acids, and amino acids. Transcripts of AUX/IAA family proteins that repress the activities of auxin-induced proteins were expressed in berry skin at the end of $v{\acute{e}}raison$. Transcripts of genes related to the ubiquitin-proteasome system that degrades AUX/IAA family proteins were abundantly expressed in berry skin at the end of ripening, suggesting that the expansion of skin cells at $v{\acute{e}}raison$ is suppressed by AUX/IAA family proteins, and that the ubiquitin-proteasome system induces the expansion of skin cells during ripening by degrading AUX/IAA family proteins. These transcriptional profiles, which provide new information on the characteristics of 'Koshu' grapevine during ripening, may explain the unique characteristics of 'Koshu' grape in comparison with those of European grapes used for winemaking, and may contribute to the improvement of 'Koshu' grape quality.

• Journal of Photoscience
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• v.11 no.3
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• pp.121-127
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• 2004

The${\beta}$-glucosidases occur widely in all living organisms and has in general a tendency to form oligomers of varying numbers of subunits or aggregates, although the functional implications of such diverse oligomerization schemes remain unclear. In particular, the assembly mode of the oat ${\beta}$-glucosidase is very unique in that it multimerizes by linear stacking of a hexameric building block to form long fibrillar multimers. Some structural proteins such as actin and tubulin assemble into long fibrils in a helical fashion and several enzymes such as GroEL and Pyrodictium ATPase functional complexes, 20S proteasome of the archaebacterium Thermoplasma acidophilum, and lutamine synthetase fromblue-green algae, assemble into discrete oligomers upto 4 stacked rings to maintain their enzymatic activities. In particular, oat ${\beta}$-glucosidase exists in vivo as a discrete long fibrillar multimer assembly that is a novel structure for enzyme protein. It is assembled by linear stacking of hollow trimeric units. The fibril has a long central tunnel connecting to the outer medium via regularly distributed side fenestrations. The enzyme active sites are located within the central tunnel and multimerization increases enzyme affinity to the substrates and catalytic efficiency of the enzyme. Although it is suggested that oligomerization may contribute to the enzyme stability and catalytic efficiency of ${\beta}$-glycosidases, the functional implications of such diverse oligomerization schemes remain unclear so far.

• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.4
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• pp.287-296
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• 2005

To investigation protein expression pattern in rice leaves exposed to cold stress, the soluble proteins extracted from leaf tissue were fractionated with $15\%$ PEG and separated by two-dimensional polyacrylamide gel electrophoresis (2-DE). Differentially expressed proteins were identified by peptide mass fingerprinting using matrix assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). Eight proteins up-regulated and 10 down-regulated were found in $15\%$ PEG supernatant fraction. In addition, 13 proteins up-regulated and 14 down-regulated were found in $15\%$ PEG pellet fraction. It was identified the differentially expressed proteins in $15\%$ PEG supernatant fraction as pimerase/dehydratase fructokinase, ribose-5-phosphate isomerase (Rpi), chaperonin 21 precursor, probable photosystem II oxygen-envolving complex (PS II OEC) protein 2 precursor and thioredoxin h-type (Trx-h) and those in $15\%$ PEG pellet fraction as OSINBb0059K02.15, hypothetical protein, putative mitogen-activated protein kinase kinase (MAPKK), beta 7 subunit of 205 proteasome, ribulose-1, 5-bisphosphate carboxylase/oxygenase (Rubisco) small subunit. These proteins are involved in metabolism, energy, protein synthesis, disease/defense and signal transduction-related proteins.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.1
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• pp.20-25
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• 2009

Xenotransplantation of pig organs into humans is a potential solution for the shortage of donor organs for transplantation. However, multiple immune barriers preclude its clinical application. In particular, the initial type of rejection in xenotransplantation is an acute cellular rejection by host $CD8^+$ cytotoxic T lymphocyte (CTL) cells that react to donor major histocompatibility complex (MHC) class I. The human cytomegalovirus (HCMV) glycoprotein Unique Short (US) 2 specifically targets MHC class I heavy chains to relocate them from the endoplasmic reticulum (ER) membrane to the cytosol, where they are degraded by the proteasome. In this study we transfected the US2 gene into minipig fetal fibroblasts and established four US2 clonal cell lines. The integration of US2 into transgenic fetal cells was confirmed using PCR and Southern blot assay. The reduction of Swine Leukocyte Antigen (SLA)-I by US2 was also detected using Flow cytometry assay (FACS). The FACS analysis of the US2 clonal cell lines demonstrated a substantial reduction in SLA-I surface expression. The level (44% to 76%) of SLA-I expression in US2 clonal cell lines was decreased relative to the control. In cytotoxicity assay the rate of $CD8^+$ T cell-mediated cytotoxicity was significantly reduced to 23.8${\pm}$15.1% compared to the control (59.8${\pm}$8.4%, p<0.05). In conclusion, US2 can directly protect against $CD8^+$-mediated cell lysis. These results indicate that the expression of US2 in pig cells may provide a new approach to overcome the CTL-mediated immune rejection in xenotransplantation.

• Tuberculosis and Respiratory Diseases
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• v.48 no.2
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• pp.166-179
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• 2000

Background: The main reason for the failure of anti-cancer chemotherapy is the build up of resistance by cancer cells to apoptosis. The activation of NF-${\kappa}B$ in many cancer cell lines is reported to be underlying mechanism behind the build up of resistance of cancer cells to apoptosis. However, this relationship varied depending on the cells used in the experiments. In this study, the role of NF-${\kappa}B$ activation in the TNF-$\alpha$-induced apoptosis in lung cancer cell line was evaluated. Methods: NCI-H157 cells were used in all experiments. Cells were exposed to a high dose of TNF-$\alpha$(20 ng/ml) for 24 or 48 hours with or without blocking NF-${\kappa}B$ activation. TNF-$\alpha$-induced activation of NF-${\kappa}B$ was inhibited either by overexpression of $I{\kappa}B{\alpha}$-super repressor($I{\kappa}B{\alpha}$-SR) or by pre-treatment with proteasome inhibitor. Cell viability and apoptosis were evaluated with MTT assay and Western blot analysis for PARP fragment, respectively. Results: Cell viability of NCI-H157 cells was not affected by TNF-$\alpha$ treatment alone; however, combined treatment with TNF-$\alpha$ and cycloheximide reduced cell viability significantly, indicating that resistance to TNF-$\alpha$ is mediated by the new proteins synthesized after TNF-$\alpha$ stimulation. To evaluate the role of NF-${\kappa}B$ in the transcription of anti-apoptotic proteins. delete NF-${\kappa}B$ activation was inhibited before TNF-$\alpha$ stimulation. as described above. $AD5I{\kappa}B{\alpha}$-SR-transduction inhibited TNF-$\alpha$-induced nuclear translocation of p65. TNF-$\alpha$-induced cell death and apoptosis increased after inhibition of TNF-$\alpha$-induced activation of NF-${\kappa}$ by methods. Conclusion: These results suggest that TNF-$\alpha$-induced activation of NF-${\kappa}B$ may be closely related to the acquisition of the resistance to TNF-$\alpha$-induced apoptosis in lung cancer cells. Therefore. blocking of NF-${\kappa}B$ pathway can be a useful therapeutic modality in the treatment of lung cancer.

• Food Science of Animal Resources
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• v.42 no.2
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• pp.266-279
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• 2022

This study was conducted to evaluate the proteolysis trends and change in meat quality during 10 days of cold storage in duck M. pectoralis major (PM) and M. iliotibialis (IL). Duck IL had a higher pH and greater degree of lightness but lower cooking loss than PM (p<0.05). During the 10-day cold storage, the pH value of PM declined significantly (p<0.05), while the meat quality traits of IL were not affected by cold storage (p>0.05). In PM, the redness increased from day 1 to day 5, while cooking loss was lower on day 10 compared to day 5 (p<0.05). There were no significant differences in the activities of cathepsin B and proteasome 20S during cold storage (p>0.05). The activity of calpains declined gradually during 10 days of storage (p<0.05), and the activity of calpains in PM was higher than that in IL (p<0.05). A total of 5,155 peptides were detected and derived from 34 proteins of duck PM muscle, whereas 4,222 peptides derived from 32 proteins were detected from duck IL muscle. Duck PM muscle was composed only of fast type of muscle fiber, whereas IL muscle was composed of both slow and fast types. The proteins responsible for glycolysis or myofibrillar proteins were closely related to changes in meat color or water-holding capacity during cold storage. These results suggest that changes in meat quality characteristics during cold storage are closely related to protein degradation, which is also related to the distribution of muscle fiber types.