• Fisheries and Aquatic Sciences
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• 제2권1호
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• pp.85-92
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• 1999

We examined the expression patterns of heat shock proteins in primary cultured hepatocytes from flounder (Paralichthys olivaceus) exposed to heat shock. The expression of hsp90, hsp70, hsp40, hsp30, and hsp27 was induced and major polypeptides were hsp70, hsp30 and hsp27. Northern blot analysis showed that expression of hsp70 was inhibited by transcriptional inhibitor actinomycin D, suggesting that expression of hsp70 gene is regulated at the transcriptional level. Prolonged exposure of cells to an elevated incubation temperature $(30^{\circ}C)$ induced the transient synthesis of hsp90, hsp70, hsp40, and hsp30 whereas maintenance of cells at a slightly higher incubation temperature $(32^{\circ}C)$ induced the continuous syntheses of these hsps. When cells were incubated at a higher temperatures $(35^{\circ}C\;or\;37^{\circ}C)$, the synthesis of hsps was almost similar to that of hsps in cells exposed to 32't except for the induction of hsp27 synthesis. These results that temperature and incubation time for optimum expression of each hsp during prolonged heat shock are different.

• 한국동물학회지
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• 제36권3호
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• pp.373-379
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• 1993

초파리에서 정상 발생동안 HSP23의 합성과 생리적 기능이 20-hydroxyecdysone과 어떤 연관을 가지는지를 조사하였다. HSP23 유전자의 발현을 Northern blotting과 Western blotting으로 조사하였고, 20HE의 분비 양상은 radioimmunoassay 법으로 조사하였다. HSP23은 3령기 초기부터 발현이 시작되어 pupariation 시기에 급격한 증가를 보인 후 감소하였다. HSP23과 20HE의 합성을 비교하였을 때, 3령기-초기 pupa 시기에 두 분자가 모두 합성의 최고치를 보이며 유사한 합성 양상을 보였지만 그 외 시기는 일치하지 않았다. 따라서 20HE는 larva에서 pupa로의 변태 시기에 HSP23 유전자의 발현을 조절하며, 또 HSP23을 이용하여 변태과정의 일부를 조절하는 것으로 보인다.

• Journal of Microbiology
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• 제34권1호
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• pp.30-36
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• 1996

We have exmained the re-establishment of HIMRE mediated silencing function on the transcriptional activity of yeast heast shock gene HSP82. To test whether the onset of SIR repression can occur in growing cells in the rpesence of a potent inhibitor of DNA replication, HMRa/HSP82 strains with SIR4- and SIR4S$^{+}$ genetic backgrounds were arrested in S phase by incubation of a culture in 200 mM hydroxyurea for 120 min. It was clear that following a 20 minute heat shock, silencing of the HMRa/HSP82 allele in cells pretreated with hydroxyurea does occur in a SIR4-dependen fashion, even though the kinetics of repression appears to be substantially delayed. We also have tested whether re- establishement of silencing at the HMR/hsp82 locus can occur in G1-arrested cells. Cell cycle arrest at G1 phase was achieved by treatment of early log a cell cultures with .alpha.-factor mating pheromone, which induces G1 arrest. The result suggests that passage through S phase (and therefore DNA replication) is nor required for re-establishing silencer-mediated repression at the HMNRa/HSP82 locus. Finally, to test whether de nono protein synthesis is required for re-establishment of silencer-mediated repression, cells were pretreated with cycloheximide (500 /.mu.g/ml) 120 min. It was apparent that inhibiting protein synthesis delays, but does not prevent, re-establishment of silencer-mediated repression. Altogether, these results indicate that re-establishment of silencer-mediated repression is not dependent on the DNA replication and has no requirement for protein synthesis.s.

• 한국환경보건학회지
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• 제22권4호
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• pp.91-101
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• 1996

Exposure indices are important tools which enable scientists to reliably predict and detect exposures to xenobiotics and resultant cell injury. Since the de novo synthesis of stress proteins can be detected early after exposure to some agents, analysis of toxicant-induced changes in gene expression, i.e. alterations in patterns of protein synthesis, may be useful to develop as biomarkers of exposure and toxicity. The acute and chronic effects of cadmium(Cd, $CdCl_2$ 20 mg/kg) on Wistar male rats were evaluated concerning cadmium contents, tissues enzyme activity, HSP expression. The results of the study were as follows: 1. Less cadmium was absorbed through the digestive tracts, but the ratio of contents in renal to hepatic cadmium was higher at 8 weeks after treatment. 2. ALT(alanine aminotransferase), AST(aspartate aminotransferase), glucose, BUN(blood urea nitrogen), creatinine, the key indices of the clinical changes in hepatic and renal function were significantly changed by the cadmium treatment after 1 week in liver, after 4 weeks in kidney. 3. Enhanced synthesis of 70 KDa relative molecular mass proteins were detected in 2 hours after cadmium exposure, with maximum activity occurring at 8~48 hours. Induction of $HSP_{70}$ was evident at proximal tubules and glomeruli in kidney. Testicular cells produced enough HSP to be detected normally. From the above results, it could be concluded that $HSP_{70}$ induction by the cadmium treatment was a rapid reaction to indicate the exposure of xenobiotics.

• 생명과학회지
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• 제18권3호
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• pp.304-310
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• 2008

고온 단백질 heat shcok protein 70 (HSP70)은 분자샤페론으로써 환경스트레스와 발달단계 동안 단백질을 보호하고 합성하는 다양한 과정에 관여하는 기본적인 단백질이다. 하지만 그 생물학적 기능이 식물에서 아직 정확하게 밝혀지지 않았다. 이에 본 연구에서는 담배에서 고온에 의해 유도된 HSP70인 NtHSP70-1 (AY372069)를 분리하여 그 기능을 연구하였다. NtHSP70-1의 고온 내성 기능을 분석하기 위해 NtHSP70-1이 식물 형질전환용 벡터인 pBKS1-1에 sense 또는 antisense 방향으로 도입되어 형질전환된 식물체와 pBKS1-1만 도입된 형질전환 식물체들을 제조하였다. 형질전환체에 있어서 NtHSP70-1의 발현량은 western blot 분석법을 사용하여 수행하였고 확인된 형질전환체들은 고온 내성 기능분석에 이용되었다. 그 결과 고온 환경에 있어서 NtHSP70-1이 과다발현된 형질전환체들은 그 클로로필의 함량과 생존율이 정상환경 일 때와 유사하였고 반대로 벡터 또는 벡터인 pBKS1-1에 antisense 방향으로 도입되어 형질전환된 식물체들은 클로로필의 파괴로 인한 감소된 생존율을 나타내었다. 고온 처리된 형질전환 식물체에서 클로로필의 함량비교 결과로 NtHSP70-1이 클로로필을 보호함으로써 식물의 고온내성에 기여함을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3345-3349
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• 2013

Hsp90 shows great promise as a therapeutic target due to its potential to disable multiple signaling pathways simultaneously. In this study, we discovered that a natural product, butein moderately inhibited the growth of drug-resistant cancer cells (A2780cis and H1975), and brought about the degradation of oncogenic Hsp90 client proteins. The study demonstrated that butein would be a therapeutic lead to circumvent drug-resistance in cancer chemotherapy. The structure-based screening, synthesis, and biological evaluation of butein are described herein.

• 생명과학회지
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• 제17권12호
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• pp.1760-1765
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• 2007

생명체 내에서 일어나는 거의 모든 반응은 단백질이 촉진하거나 수행한다. 단백질은 세포질과 소포체에서 합성될 때 엄격하게 조절된다. 그러나, 새로이 합성된 모든 단백질이 살아남아서 생명을 유지시키는 기능에 관여하게 되지는 않는다. 가장 알맞은 생리학적 in vitro 실험 조건에서 새로이 합성된 단백질의 약 3분의 1 정도는 합성되자마자 proteasome에 의해 빠르게 분해된다고 보고되었다. 또한, 단백질은 합성이 성공적으로 이루어진 이후에는 3차원 구조를 갖기 위해 접힘(folding)이 이루어져야 하고, subunit들은 assembly 과정을 거쳐야 비로소 성숙된 단백질로서 기능을 하게 된다. 어떤 단백질군은 자연적으로 접힘이 일어나는 반면 어떤 단백질군은 분자 샤페론(molecular chaperones)과 folding enzymes의 도움을 받아야만 접힘이 일어난다. 분자 샤페론은 세포 전역에 분포하고 있으며, 세균에서부터 고등 동식물에 이르기까지 모든 생명체에 존재한다. 이들 중 Hsp70군은 많이 연구된 분자 샤페론으로서 지난 10여년 동안 조절인자들이 새로이 발견되어 작용 mechanism이 보다 자세히 밝혀졌다. 본 총설에서 Hsp70군과 그 조절인자들에 대한 전반적인 서술을 하였으며, 이들의 기능이 분자 샤페론 기능 외에 생체 내에서 중요한 기능들이 새롭게 밝혀지고 있어 이들의 작용 mechanism을 조명함으로 이해를 돕고자 한다.

• 미생물학회지
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• 제29권1호
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• pp.49-55
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• 1991

The heat shock responses of Campylobacter jejuni were studied by examination of their survival rates and synthesis of heat shocd proteins. When C. jejuni cells were treated at the sublethal temperatures of 48.deg.C for 30 minutes, most of the cells maintained their viabilities and synthesized the heat shock proteins of 90, 73, and 66 kD in molecular weight. By the method of two-dimensional electrophoresis, the heat shock proteins of C. jejuni were identified to be Hsp90, Hsp73, and Hsp66. During the heat shock at 48.deg.C, the heat shock proteins were induced from about 5 minutes after the heat shock treatment. Their synthesis was continued upto 30 minutes, but remarkably retarded after 50 minutes. When C. jejune cells were heat shocked at 51.deg.C for 30 minutes, the survival rates of the cells were decreased by about $10^{3}$ fold and synthesis of heat shock proteins and normal proteins was also generally retarded. The cells exposed to 55.deg.C for 30 minutes died off by more than $10^{5}$ cells and the new protein synthesis was not observed. But when C. jejuni cells were heat-shocked at the sublethal temperature of 48.deg.C for 15 to 20 minutes and then were exposed at the lethal temperature of 55.deg.C for 30 minutes, their viabilities were higher than those exposed at 55.deg.C for 30 minutes without pre-heat shock at 48.deg.C. Therefore, the heat shock proteins synthesized at the sublethal temperature of 48.deg.C in C. jejuni were thought to be responsible for thermotolerance. However, when C. jejuni cells heat-shocked at various ranges of sublethal and lethal temperatures were placed back to the optimum temperature of 42.deg.C, the multiplication patterns of the cells pretreated at different temperatures were not much different each other.

• Bulletin of the Korean Chemical Society
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• 제35권4호
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• pp.1154-1158
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• 2014

Hsp90 is an ubiquitous molecular chaperone protein, which plays an important role in regulating maturation and stabilization of many oncogenic proteins. Due to its potential to simultaneously disable multiple signaling pathways, Hsp90 represents great promise as a therapeutic target of cancer. In this study, we synthesized flavokawain analogues and evaluated their biological activities against drug-resistant cancer cells. The study indicated that compound 1i impaired the growth of gefitinib-resistant non-small cell lung cancer (H1975), down-regulated the expression of Hsp90 client proteins including EGFR, Her2, Met, Akt and Cdk4, and upregulated the expression of Hsp70. The result strongly suggested that compound 1i inhibited the proliferation of cancer cells through Hsp90 inhibition. Overall, compound 1i could serve as a potential lead compound to overcome the drug resistance in cancer chemotherapy.

• 한국동물학회지
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• 제39권2호
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• pp.123-131
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• 1996

In this study, we examined the expression of heat shock proteins (HSPs) in fish cell line CHSE-2lnl and human HeLa cells exposed to heat shock. In fish CHSE-214 cells HSP70 was the major polvpeptide induced by an elevated temperature or an amino acid analog, while in HeLa cells HSP90 as well as HSP70 were prominently enhanced in response to these stresses. Pretreatment of actinomvcin D prior to heat shock completely inhibited the induction of fish HSP70, indicating the transcriptional regulation of fish HSP70 gene expression. In HeLa and CHSE-214 cells either recovering from heat shock or experiencing prolonged heat shock, attenuation in the HSP90 a'nd HSP70 induction occurred but both induction and repression of HSP70 synthesis appear 19 precede those of HSP90. Moreover, attenuation did not occur in the syntheses of 40 kDa and 42 kOto proteins which were only induced in CHSE-214 cells. The enhanced syntheses of these he proteins continued as long as CHSE-214 cells were Siven heat shock. These results suggest that down-regulation of HSP syntheses during prolonged heat shock may be controlled by several different. as vet undefined, mechanisms.