• Journal of the Korean Magnetic Resonance Society
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• v.28 no.2
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• pp.6-9
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• 2024

HscA is a Hsp70-type chaperone protein that plays an essential role to mediate the iron-sulfur (Fe-S) cluster biogenesis mechanism in Escherichia coli. Like other Hsp70 chaperones, HscA is composed of two domains: the nucleotide binding domain (NBD), which can hydrolyze ATP and use its chemical energy to facilitate the Fe-S cluster transfer process, and the substrate binding domain (SBD), which directly interacts with the substrate, IscU, the scaffold protein of an Fe-S cluster. In the present work, we prepared the isolated SBD construct of HscA (HscA(SBD)) and conducted the solution-state nuclear magnetic resonance (NMR) experiments to have its backbone chemical shift assignment information. Due to low spectral quality of HscA(SBD), we obtained all the NMR data from the sample containing the peptide LPPVKIHC, the HscA-interaction motif of IscU, from which the chemical shift assignment could be done successfully. We expect that this information provides an important basis to execute detailed structural characterization of HscA and appreciate its interaction with IscU.

• Korean Journal of Ecology and Environment
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• v.53 no.4
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• pp.324-330
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• 2020

Ozone (O₃) is a general disinfectant to remove micro-pollutants in water treatment system. Previous studies have reported effect of ozone to bacteria and pathogens removal, but its effect to the relatively large organisms has little known. In this study, we investigated potential effects of ozone toxicity to the non-bite midge larvae (Glyptotendipes tokunagai) with accumulate mortality, coloration change and expression of heat shock protein 70 (HSP70). The accumulate mortality rate of G. tokunagai increased in a dose-time dependent manner and the highest mortality rate was observed to 75% at 30 minute of exposure duration with 2.0 ppm of ozone concentration. Exposure to ozone was a factor increasing body color of the larvae. The tendency of HSP70 mRNA expression showed up-regulation in ozone exposure at 20 minute. After that time, the expression of HSP70 in exposed group decreased to a similar level of control group. Our results clearly showed that ozone toxicity affects physical and molecular activity of G. tokunagai, implying the potential hazardous of ozone in the aquatic ecosystem including macroinvertebrates.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4475-4482
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• 2014

Background: Cisplatin, a DNA damaging agent, induces apoptosis through increasing DNA fragmentation. However, identification of intrinsic resistance molecules against Cisplatin is vital to estimate the success of therapy. Bag-1 (Bcl-2-associated anthanogene) is one anti-apoptotic protein involved in drug resistance impacting on therapeutic efficiency. Elevated levels of this protein are related with increase cell proliferation rates, motility and also cancer development. For this reason, we aimed to understand the role of Bag-1 expression in Cisplatin-induced apoptosis in HeLa cervix cancer cells. Cisplatin decreased cell viability in time- and dose-dependent manner in wt and Bag-1L+HeLa cells. Although, $10{\mu}M$ Cisplatin treatment induced cell death within 24h by activating caspases in wt cells, Bag-1L stable transfection protected cells against Cisplatin treatment. To assess the potential protective role of Bag-1, we first checked the expression profile of interacting anti-apoptotic partners of Bag-1. We found that forced Bag-1L expression prevented Cisplatin-induced apoptosis through acting on Mcl-1 expression, which was reduced after Cisplatin treatment in wt HeLa cells. This mechanism was also supported by the regulation of heat shock protein (Hsp) family members, Hsp90 and Hsp40, which were involved in the regulation Bag-1 interactome including several anti-apoptotic Bcl-2 family members and c-Raf.

• Animal cells and systems
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• v.14 no.4
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• pp.267-274
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• 2010

The decrease in sperm quality under heat stress causes a great loss in animal husbandry production. In order to reveal the mechanism underlying the sperm quality decrease caused by heat stress, we first established a mild heat-treated mouse model. Then, the sperm quality was identified. Further, the testicular proteome profile was mapped and compared with the control using 2D electrophoresis and mass spectrometry. Finally, the differential expressed proteins involved in the heat stress response were identified by real-time PCR and Western blotting. The results showed that heat stress caused a significant reduction in mouse sperm quality (P<0.05). Further, 52 protein spots on the 2D gel were found to differ between the heat-shocked tissues and the control. Of these spots, some repair proteins which might provide some explanation for the influence on sperm quality were found. We then focused on Bag-1, Hsp40, Hsp60 and Hsp70, which were found to be differently expressed after heat shock (P<0.05). Further analysis in this heat-shocked model suggests numerous potential mechanisms for heat shock-induced spermatogenic disorders.

• YAKHAK HOEJI
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• v.51 no.4
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• pp.264-269
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• 2007

Alzheimer’s disease (AD) is characterized pathologically by the presence of intracellular neurofibrillary tangles and deposition of ${\beta}-amyloid $ (A ${\beta}$) peptides, which are generated by processing of amyloid precursor protein (APP). It is urgent to develop effective therapies for the treatment of AD, since our society rapidly accelerate aging. A${\beta}$ peptides have been believed to be neurotoxic and now are also considered to have effects on the mechanism of memory formation. In this study, effects of radicicol on the metabolism of APP were analyzed. Radicicol inhibited the secretion of A${\beta}$ from the Neuro2a cell line (APPswe cell) expressing APPswe. Beta-site APP cleaving enzyme (BACE) fluorescence resonance energy transfer (FRET) assay revealed that it inhibited BACE activity in a dose dependently manner. Immunoblotting study showed that it inhibited intracellular heat shock protein (HSP)90 and it increased the secretion of HSP90 from the APPswe cells. We suggest that radicicol inhibits APP metabolism and Ap generation by the means of HSP90 inhibitory mechanism and partially BACE inhibitory mechanism. This is the first report that radicicol inhibits the secretion of A${\beta}$ peptides from neuroblastoma cells.

• Journal of Aquaculture
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• v.13 no.2
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• pp.181-186
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• 2000

Relationship between hsp 70 expression and development of thermotolerance in the olive flounder was investigated by exposing the fish to 23 or 26$^{\circ}C$ for 1 h. After selected intervals, they were re-exposed to 31$^{\circ}C$ for a duration of 15 min. Theremotolerance rapidly developed with increasing interval and peaked at 3 h interval. Subsequently, it gradually decayed and disappeared by 24 h interval. The flounder displayed remarkably high levels of hsp 70 mRNA and protein, as compared to control flounder. Hence, the olive flounder acquires thermotolerance, which is positively correlated with the synthesis of hsp 70.

• Bulletin of the Korean Chemical Society
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• v.22 no.5
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• pp.514-518
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• 2001

We have explored the importance of two ATP binding domains of Hsp104 protein in protection of yeast cells from cadmium exposure. In the previous study we have discovered that the presence of two ATP binding sites was essential in providing heat sh ock protection as well as rescuing cells from oxidative stress. In this paper we first report wild type cell with functional hsp104 gene is more resistant to cadmium stress than hsp104-deleted mutant cell, judging from decrease in survival rates as a result of cadmium exposure. In order to demonstrate functional role of two ATP binding sites in cadmium defense, we have transformed both wild type (SP1) and hyperactivated ras mutant (IR2.5) strains with several plasmids differing in the presence of ATP binding sites. When an extra copy of functional hsp104 gene with both ATP binding sites was overexpressed with GPD-promoter, cells showed increased survival rate against cadmium stress than mutants with ATP binding sites changed. The degree of protection in the presence of two ATP binding sites was similarly observed in ira2-deleted hyperactivated ras mutant, which was more sensitive to oxidative stress than wild type cell. We have concluded that the greater sensitivity to cadmium stress in the absence of two ATP binding sites is attributed to the higher concentration of reactive oxygen species (ROS) produced by cadmium exposure based on the fluorescence tests. These findings, taken all together, imply that the mechanism by which cadmium put forth toxic effects may be closely associated with the oxidative stress, which is regulated independently of the Ras-cAMP pathway. Our study provides a better understanding of cadmium defense itself and cross-talks between oxidative stress and metal stress, which can be applied to control human diseases due to similar toxic environments.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.6
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• pp.469-476
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• 2012

2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) is an environmental toxicant with a polyhalogenated aromatic hydrocarbon structure and is one of the most toxic man-made chemicals. Exposure to 2,3,7,8-TCDD induces reproductive toxicity, immunotoxicity, and hepatotoxicity. In this study, we evaluated how 2,3,7,8-TCDD-induced hepatotoxicity affect the expression of heat shock proteins and antioxidant enzymes using the real-time polymerase chain reaction (PCR) in rat. 2,3,7,8-TCDD increased heat shock protein (Hsp27, ${\alpha}$-B-crystallin, Mortalin, Hsp105, and Hsp90s) and antioxidant enzymes (SOD-3, GST and catalase) expression after a 1 day exposure in livers of rats, whereas heat shock protein (${\alpha}$-B-crystallin, Hsp90, and GRP78) and antioxidant enzymes (SOD-1, SOD-3, catalase, GST, and GPXs) expression decreased on day 2 and then slowly recovered back to control levels on day 8. These results suggest that heat shock proteins and antioxidant enzymes were induced as protective mechanisms against 2,3,7,8-TCDD induced hepatotoxicity, and that prolonged exposure depressed their levels, which recovered to control levels due to reduced 2,3,7,8-TCDD induced hepatotoxicity.

• Childhood Kidney Diseases
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• v.18 no.1
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• pp.24-28
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• 2014

Purpose: The purpose of this study was to assess the therapeutic efficacy of methylprednisolone pulse therapy in children with IgA nephropathy and Henoch- Sch$\ddot{o}$nlein Purpura (HSP) nephritis combined with proteinuria. Methods: We retrospectively reviewed the clinical records of 21 patients who were diagnosed with IgA nephropathy and HSP nephritis based on percutaneous renal biopsy. Of the 21 patients, 15 were diagnosed with IgA nephropathy and 6 were diagnosed with HSP nephritis. They had mild to severe proteinuria at the time of diagnosis or during follow-up. Group 1 (n=7) received methylprednisolone pulse therapy three times every couple of months, and Group 2 (n=14) received oral steroid therapy. The follow-up periods for Group 1 and 2 were 14.0 (9-54) months and 26.5 (14-34) months, respectively. There was no significant difference in the follow-up duration between the two groups. Results: The average age at diagnosis and biopsy was lower in Group 1 compared to Group 2, but it was not significantly different. At admission, all patients in both groups had hematuria and 5 patients (71.4%) of Group 1 and 14 patients (100 %) of Group 2 had proteinuria. Before treatment, there was no significant difference of spot urine protein/creatinine ratio between the two groups. During followup, 7 patients of Group 1 (100%) and 10 patients of Group 2 (71.4%) showed complete improvement of proteinuria and the spot urine protein/creatinine ratio in Group 1 was significantly lower than Group 2. Conclusion: In patients with IgA nephropathy and HSP nephritis with proteinuria, methylprednisolone pulse therapy was more effective than oral steroid therapy in the reduction of proteinuria. To investigate the effects on long-term prognosis, large-scale prospective studies are needed.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5779-5785
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• 2015

The present study was designed to investigate cholangiocarcinoma (CCA) antibodies in hamster serum. Hamster CCA cell lines were processed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. A candidate biomarker was confirmed by immunoprecipitation and western blot, and was further analyzed using ELISA and sera from normal control hamsters, hamsters with opisthorchiasis and hamsters with various stages of CCA, as well as from CCA patients and healthy individuals. One candidate marker was identified as $HSP90{\alpha}$, as indicated by a high level of anti-$HSP90{\alpha}$ in hamster CCA sera. It was found that the levels of anti-$HSP90{\alpha}$ were specifically elevated in the sera of hamsters with CCA compared with other groups and progressively increased with the clinical stage. At the cut-off point of 0.4850 on the receiver operating characteristic curve, anti-$HSP90{\alpha}$ could discriminate CCA from healthy control groups with a sensitivity of 76.2%, specificity of 71.4% and total accuracy 75.5%. In the present study, we have shown that anti-$HSP90{\alpha}$ may be a potential useful serum biomarker to discriminate CCA cases from healthy persons.