• The Korean Journal of Zoology
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• v.31 no.3
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• pp.157-164
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• 1988

SCK tumor cells were exposed to heat shock or several sulihydryl-reacting agents such as iodoacetamide(IAA), zinc chloride(Zn), and 2-mercaptoethanol(ME). Stress proteins induced by these agents were examined and the relationship between the induction of stress proteins and the production of abnormal proteins was discussed. Based on the present experiments, two classes of intracellular pathways for the induction of stress proteins were defined; one dependent on and the other independent of protein synthesis. The presence of cycloheximide during the induction period blocked the formation of stress proteins in the cells exposed to Zn or ME, but not in those exposed to heat shock or IAA.Therefore, stress protein seems to be induced either by denaturation of pre-existing mature proteins (e.g., heat shock or IAA) or by newly synthesized abnormal proteins(e.g., Zn or ME). In conclusion, it is ilkely that the production of abnormal proteins by stresses triggers stress protein induction. In addition, it was found that the cells exposed to IISP and GRP inducers simultaneously responded to more strong stress among several stresses encountered.

• The Korean Journal of Zoology
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• v.28 no.2
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• pp.108-119
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• 1985

Aimed at elucidating the modulation of stress protein gene expression, the effect of environmental stress and pH on the induction of stress protein synthesis has been analyzed using SDS-polyacrylamide gel electrophoresis. Although the general patterns of protein synthesis in MEF and SCK cells are different, stress protein patterns are identical in both cells. Among three stress proteins, the $SP_70$ exhibits an interesting kinetics of induction and decay. The kinetics of $SP_70$ under acidic or normal pH appears to be similar, but the degree of hyperthermia and duration of treatment required for maximum induction are found to be different, being lower temperatures and shorter durations under acidic pH compared to those under normal pH. Inducation of stress protein and the accumulation of mRNA coding for stress proteins are blocked with actinomycin D, indicating the new RNA transcription is required for stress blocked with actinomycin D, indicating that new RNA transcription is required for stress protein induction. Treatment of cycloheximide during the after hyperthermia indicates that no specific protein is required for the induction of stress protein synthesis. Based on our preliminary data, we postulate that induction of stress protein synthesis in MEF and SCK cells is regulated primarily at the level of transcription and that $SP_70$ autoregulates its synthesis and levels of this protein are correlated with the stresseed state of a cell.

• Molecules and Cells
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• v.41 no.8
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• pp.705-716
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• 2018

The endoplasmic reticulum (ER) is a critical organelle for protein synthesis, folding and modification, and lipid synthesis and calcium storage. Dysregulation of ER functions leads to the accumulation of misfolded- or unfolded-protein in the ER lumen, and this triggers the unfolded protein response (UPR), which restores ER homeostasis. The UPR is characterized by three distinct downstream signaling pathways that promote cell survival or apoptosis depending on the stressor, the intensity and duration of ER stress, and the cell type. Mammalian cells express the UPR transducers IRE1, PERK, and ATF6, which control transcriptional and translational responses to ER stress. Direct links between ER stress and immune responses are also evident, but the mechanisms by which UPR signaling cascades are coordinated with immunity remain unclear. This review discusses recent investigations of the roles of ER stress in immune responses that lead to differentiation, maturation, and cytokine expression in immune cells. Further understanding of how ER stress contributes to the pathogenesis of immune disorders will facilitate the development of novel therapies that target UPR pathways.

• BMB Reports
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• v.45 no.5
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• pp.317-322
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• 2012

2-deoxy-D-glucose(2DG)-caused endoplasmic reticulum (ER) stress inhibits protein phosphorylation at tyrosine residues. However, the accurate regulatory mechanisms, which determine the inflammatory response of chondrocytes to ER stress via protein tyrosine phosphorylation, have not been systematically evaluated. Thus, in this study, we examined whether protein phosphorylation at tyrosine residues can modulate the expression and glycosylation of COX-2, which is reduced by 2DG-induced ER stress. We observed that protein tyrosine phosphatase (PTP) inhibitors, sodium orthovanadate (SOV), and phenylarsine oxide (PAO) significantly decreased expression of ER stress inducible proteins, glucose-regulated protein 94 (GRP94), and CCAAT/ enhancer-binding-protein- related gene (GADD153), which was induced by 2DG. In addition, we demonstrated that SOV and PAO noticeably restored the expression and glycosylation of COX-2 after treatment with 2DG. These results suggest that protein phosphorylation of tyrosine residues plays an important role in the regulation of expression and glycosylation during 2DG-induced ER stress in rabbit articular chondrocytes.

• BMB Reports
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• v.43 no.2
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• pp.103-109
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• 2010

Modification of proteins by the reversible covalent addition of the small ubiquitin like modifier (SUMO) protein has important consequences affecting target protein stability, sub-cellular localization, and protein-protein interactions. SUMOylation involves a cascade of enzymatic reactions, which resembles the process of ubiquitination. In this study, we characterized the SUMOylation system from an important crop plant, rice, and show that it responds to cold, salt and ABA stress conditions on a protein level via the accumulation of SUMOylated proteins. We also characterized the transcriptional regulation of individual SUMOylation cascade components during stress and development. During stress conditions, majority of the SUMO cascade components are transcriptionally down regulated. SUMO conjugate proteins and SUMO cascade component transcripts accumulated differentially in various tissues during plant development with highest levels in reproductive tissues. Taken together, these data suggest a role for SUMOylation in rice development and stress responses.

• Korean Journal of Community Nutrition
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• v.2 no.2
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• pp.169-178
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• 1997

Thin study measured dietary intakes in late pregnancy and psychological stress during the period of gestation and examined the roles of diet and psychological stress in pregnancy weight gain and infant birth weight. Study subjects were 98 pregnant women who delivered infants at 2 general hospitals in Taejon city. Mean weight gain during pregnancy was 14.6$\pm$4.89Kg. Mean infant birth weight was 3.39$\pm$0.62kg in males and 3.28$\pm$0.43Kg in females. Mean energy and protein intake levels were adequate, but mean iron and calcium intakes were only 61.2$\pm$14.9% and 79.1$\pm$18.2$\%$ of RDA, respectively. Fat intake which constitutes 22.0$\pm$4.3$\%$ of total energy intake, and animal protein intake which constitutes 22.0$\pm$4.3$\%$ of total energy intake, and animal protein intake which constitutes 53.7$\%$ of total protein intake were moderately high. Though mean energy, fat, animal protein, and meat protein intakes in the low psychological stress group were higher than those in the middle or high stress group, psychological stress did not significantly affect pregnancy weight gain and infant birth weight. High intakes of nutrients except for dairy protein, iron, and niacin were associated with higher pregnancy weight gain and high intakes of protein and meat protein were associated with higher infant birth weight. It is concluded that dietary intakes during pregnancy has effects on pregnancy weight gain and infant birth weight, and psychological stress has no direct effect on them.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.1
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• pp.13-20
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• 1997

This study was designed to determine the effects of protein sources on the curation of gastric ulceration, protein metabolism, and nitrogen balance in rats with gastric ulcer induce by restraint and water immersion stress. After the rats were fed 10% casein diet for 3 weeks, four groups of the rats were forced in 5$\times$5$\times$15cm plexiglass cage. The restraint and water immersion stress was carried at 20$\pm$2$^{\circ}C$ for 8-hour. The other one group(control group) was not exposed to stress. After stress 4 kinds of different diets containing 20% protein were given for 5 days. The protein sources were casein, whey protein, soy protein, gluten. The control group was fed to 10% casein diet. The results were as follows ; the weights of rats were not different among the diet groups During the experiment period follows ; the weights of rats were not different among the diet groups during the experiment period (for 5 days). The ulcer index of rats fed 10% gluten and soy protein diet was significantly higher than those of casein and whey protein diet groups(p<0.05). The level of serum albumin was not significantly different among diet groups. But hematocrit and the level of $\alpha$-amino-N, BU and UUN of plant protein diet groups were higher than animal diet groups, the urinary hydroxyproline of soy protein group was the highest and the whey protein was the lowest. The digestibility and BV of nitrogen of gluten diet group were significantly higher than those of casein and whey protein diet groups(p<0.05). The animal proteins had more curative effects of ulcer than plant animals. The results of this study provide useful information concerning diet therapy for the patients with gastrointestinal diseases and the field of enteral diet materials.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.1
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• pp.47-53
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• 2018

Objective: The objective of this experiment was to investigate the effects of heat stress on milk protein and blood amino acid profile in dairy cows. Methods: Twelve dairy cows with the similar parity, days in milk and milk yield were randomly divided into two groups with six cows raised in summer and others in autumn, respectively. Constant managerial conditions and diets were maintained during the experiment. Measurements and samples for heat stress and no heat stress were obtained according to the physical alterations of the temperature-humidity index. Results: Results showed that heat stress significantly reduced the milk protein content (p<0.05). Heat stress tended to decrease milk yield (p = 0.09). Furthermore, heat stress decreased dry matter intake, the concentration of blood glucose and insulin, and glutathione peroxidase activity, while increased levels of non-esterified fatty acid and malondialdehyde (p<0.05). Additionally, the concentrations of blood Thr involved in immune response were increased under heat stress (p<0.05). The concentration of blood Ala, Glu, Asp, and Gly, associated with gluconeogenesis, were also increased under heat stress (p<0.05). However, the concentration of blood Lys that promotes milk protein synthesis was decreased under heat stress (p<0.05). Conclusion: In conclusion, this study revealed that more amino acids were required for maintenance but not for milk protein synthesis under heat stress, and the decreased availability of amino acids for milk protein synthesis may be attributed to competition of immune response and gluconeogenesis.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.2
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• pp.220-225
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• 2002

To determine the anti-stress effect of KCG(加味天麻鉤藤飮) extract on sprague-dawley rats. we conducted a research about the change of weight, activity, reactivity, c-fos protein, cytotoxicity against PC12 cell line and heal shock protein. 1) KCG extract siginificantly inhibited the decrease of body weight induced by stress, compared with the control group. 2) KCG extract had no siginificant effect in the activity and reactivity of rats between the control and the experimental groups. 3) KCG extract siginificantly restrained c-fos protein manifestation, compared with the control group. 4) KCG extract siginificantly restrained heat shock protein, compared with the control group. These results suggested that KCG might be usefully anti-stress effect.

• BMB Reports
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• v.31 no.2
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• pp.201-208
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• 1998

Amino acid analogs, like other inducers of stress response, induce the synthesis of stress proteins in mammalian cells. In this study, Drosophila Kc cells, in which translation is tightly controlled during stress response, was treated with proline analogs, L-azetidine-2-carboxylic acid (AzC) and 3,4-dehydro-L-proline (dh-P). Kc cells exposed to AzC or dh-P induced the synthesis of several proteins which had the same molecular weights as known heat shock proteins. However, in Kc cells, normal protein synthesis still continued in the presence of amino acids analogs unlike in heat-shocked cells. For the induction of stress response, the incorporation of dh-P into the protein was not essential, but the incorporation of AzC was. The stress protein synthesis was regulated mainly at the transcriptional level by AzC, whereas it was regulated by dh-P at the transcription level and possibly posttranscription level. During recovery, the stress protein synthesis stopped sooner in analog-treated cells than in heat-shocked cells even though the accumulated amount of Hsp70 was much less in proline analogstreated cells. It could be concluded that the proline analogs, AzC and dh-P, induced stress response through a different mechanism from heat shock.