• BMB Reports
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• v.30 no.1
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• pp.55-59
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• 1997

The heat shock response is a universal stress response observed in all organisms and cultured cells. The response is regulated at both the transcriptional and translational level. Heat shocked Drosophila melanogaster Kc cells are used as the system for the study of translational regulation. In this system non-heat shock messages are associated with polysome but are not translated in a heat shocked condition. To figure out the change in the translation machinery. the effects of translation elongation inhibitors were tested on Kc cells. The result showed that the sensitivity of translation to these drugs changed in heat shocked cells. The significant changes were the decreased inhibition of heat shock protein synthesis by cycloheximide, emetine. and puromycin. and the increased inhibition of heat shock protein synthesis by verrucarin A. implying that the translation elongation mechanism in heat shocked cells changed.

• Journal of Microbiology
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• v.33 no.3
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• pp.196-200
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• 1995

In order to express the CDC70 gene of Saccharomyces cerevisiae by heat shock, we have designed heat inducibe hybrid promoters using the Drosophila melanogaster heat shock elements (HSEs). A 220 bp-long upstream fragment of the D. melanogaster hsp70 gene comprised of four HSEs was placed upstream of the putative proximal TATA box of the CDC70 gene. Hybrid promoters containing different fusion joints were tested for their ability to drive the CDC70 gene expression by heat shock. The results showed that the HSEs of D. melanogaster conferred the heat-induced CDC70 gene expression, but the heat inducibility was much lower than that in D. melanogaster.

• The Korean Journal of Ecology
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• v.14 no.1
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• pp.75-85
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• 1991

Changes in the activities of isocitrate dehydrogenase (IDH) and glutamate dehydrogenase (GDH) and changes in free amino acids in the cytoplasm of Saccharomyces cerevisiae have been studied under heat shock condition. Heat shock conditions led to a significant decrease of NAD-IDH and NAD-GDH, It was shown appeared that the meaningful patterns of increase of NADP-IDH and NADP-GDH. It suggested that heat shock in yeast leads to a splitting of the TCA cycle and that glutamate synthesis takes place through the coupling of the NADP-linked isocirate and glutamate dehydrogenase. It was shown that about 14% of total free amino acids of yeast cells was decreased by heat shock. Especially heat shock condition resulted in the marked decreases of serine family amino acids such as serine, glycine and cysteine, and in the considerable increases of the rates of methionine, alanine, glutamin.

• Journal of Life Science
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• v.26 no.12
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• pp.1360-1366
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• 2016

Heat shock proteins (HSPs) are induced in response to various physiological or environmental stressors. However, the transcriptional activation of HSPs is regulated by a family of heat shock factors (HSFs). Fish models provide an ideal system for examining the biochemical and molecular mechanisms of adaptation to various temperatures and water environments. In this study, we examined the pattern differentials of heat shock factor 1 (HSF1) and expression of heat shock protein 70 (HSP70) in response to thermal stress in goldfish and mouse hepatocyte cultures by immune-blot analysis. Goldfish HSF1 (gfHSF1) changed from a monomer to a trimer at $33^{\circ}C$ and showed slightly at $37^{\circ}C$, whereas mouse HSF1 (mHSF1) did so at $42^{\circ}C$. This experiment showed similar results to a previous study, indicating that gfHSF1 and mHSF1 play different temperature in the stress response. We also examined the activation conditions of the purified recombinant proteins in human HSF1 (hmHSF1) and gfHSF1 using CD spectroscopy and immune-blot analysis. The purified recombinant HSF1s were treated from $25^{\circ}C$ to $42^{\circ}C$. Structural changes were observed in hmHSF1 and gfHSF1 according to the heat-treatment conditions. These results revealed that both mammal HSF1 (human and mouse HSF1) and fish HSF1 exhibited temperature-dependent changes; however, their optimal activation temperatures differed.

• Development and Reproduction
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• v.13 no.3
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• pp.199-205
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• 2009

HSP70 has widely been induced in in vivo hyperthermia conditions in various organisms to study gene regulation and recently neuroprotectve roles of the induced gene expression under varying conditions. We investigated different responses among various tissues in zebrafish under heat shock to evaluate whether spatial and temporal expression pattern of zebrafish (z) hsp70 in transcriptional and translational level under heat shock stress in different brain regions. Heat shock groups were given for 1 h at $37^{\circ}C$ after recovery by transferring the treated animals back to $28^{\circ}C$ for 1, 2 and 24 h for recovery, respectively. Control (CTRL) group was kept at $28^{\circ}C$. At the end of treatments, five animals were collected and used for isolation of total RNAs and peptides from the corresponding tissues. Expression of zhsp70 mRNA showed different patterns in recovery periods in the tissues including the brain, eye, intestines, muscles, heart and testis by RT-PCR. Unlike the RT-PCR analysis, Northern blot analysis demonstrated nearly 30-fold increase in zhsp70 at 1 h heat shock, suggesting that RT-PCR may not be appropriate in unmasking regulation of the time-dependent zhsp70 expression. In the experiment involving different brain regions, the cerebellum showed gradual activation at 1 h to R1h and decreases in R2h and R24h, while the medulla oblongata and optic tectum showed gradual increase at R1h and decrease at R24h, indicating that different brain tissues respond specifically to heat shock in inducing zhsp70 and recovering from the heat shock status. Western blot analysis also demonstrated that the intracellular levels of zHSP70 in three different brain regions including the cerebellum, medulla oblongata and optic tectum are differently induced and recovered to normal state. These results clearly demonstrate that different regions of the body and the brain tissues are responding differently to heat shock in the aspects of its level of expression and speed of recovery.

• Korean Journal of Animal Reproduction
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• v.24 no.3
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• pp.311-317
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• 2000

This study was carried out to compare the temperature and time of heat shock, and the effect of heat shock on development of embryos after in vitro maturation and fertilization in bovine oocytes. The results obtained were as follows. 1. The optimum temperature and time of heat shock were 41$^{\circ}C$ and 30sec on in vitro development of embryos from 4~8 cell to blastocyst. 2. The rates of cleavage on zygotes produced on in vitro were significantly increased by heat shock after IVM than before IVM(P<0.05). 3. When the oocytes were treated heat shock after IVM and 5 days cultured, developmental rates to blastocyst were increased than other experimental treatments.

• Food Science of Animal Resources
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• v.25 no.3
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• pp.350-356
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• 2005

We examined the enhancement of thermotolerance for storage conferred on Lactobacillus acidophilus 30SC by adaptation to different stresses. The viable cells of Lactobacillus acidophilus 30SC were compared with their viability prior to heating at $45,\;55^{\circ}C\;and\;60^{\circ}C$. Heat-adapted ($45^{\circ}C$ for 15 min) L. acidophilus 30SC in MRS broth exhibited higher survivability at lethal temperature of $55^{\circ}C$ than control. Cellular protein profiles of L. acidophilus 30SC during heat adaptation were examined with SDS-PAGE, and scanning electron microscopy. When L. acidophilus 30SC was heat-adapted at $55^{\circ}C$ for 15min, 5 new protein spots of ca $8\~45\;kDa$ size were observed on 2D SDS-PAGE. It was presumed that new proteins of L. acidophilus 30SC were produced to adapt to the environment of higher growth temperature.

• Journal of fish pathology
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• v.12 no.2
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• pp.89-99
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• 1999

New sixteen heat shock proteins (Hsps) and ten ethanol shock proteins were appeared on the analysis with SDS-PAGE when cultivation temperature for the Vibrio vulnifrcus ATCC 27562 strain was shifted-up to $42^{\circ}C$ from $30^{\circ}C$ for 20 mins and treated with of 6% ethanol for 10 mins, respectively. Even the induction of thermotolerance in V. vulnificus was coincided with the induction of Hsps if the pre-shock was adjusted to thermal temperature. Outer membrane proteins (OMPs) that were purified from the membrane of cells after heat shock showed more immunodominant pattern to the immunized rabbit anti-V. vulnificus O serum in enzyme-linked immunosorbent assay (ELISA). On the western immunoblot analysis it was confirmed that both 62 kDa IMP and 69 kDa OMP in the Hsps and 48 kDa IMP a major OMP in the ethanol shock proteins were reacted with rabbit anti-V. vulnificus O sera. Agglutination titer of the heat shocked V. vulnificus with rabbit anti-V. vulnificus O serum was higher than that of the untreated bacteria.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.6
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• pp.345-349
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• 2004

Heat shock ($43^{\circ}C$ for 60 minutes) is sufficient to induce apoptosis in a wide number of cell lines. In this study, we asked whether DNA strand breaks are responsible for this phenomenon. Using the highly sensitive comet assay for DNA damage detection, we were unable to demonstrate DNA breaks immediately after heat shock in Raji human Iymphoid cells. It showed that DNA breaks were not necessary for hyperthermic apoptosis, since its activity is indicative of DNA lesions. Here, we present a suggestion that a protein(s) is the major target for heat shock apoptosis. We firstly found glycerol, which reportedly stabilizes protein structure, showed a protective effect in Raji cells against hyperthermic apoptosis. In addition, quercetin, which modulates transcription of the heat shock protein family members, enhanced apoptotic death induced by hyperthermia. Furthermore, Raji cells are protected by a pre-mild heat treatment prior to the killing dose of heat shock.

• Journal of Microbiology and Biotechnology
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• v.25 no.8
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• pp.1234-1240
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• 2015

Heat shock RNA 1 (HSR1) is described as a "eukaryotic heat-sensing noncoding RNA" that regulates heat shock response in human and other eukaryotic cells. Highly conserved HSR1 sequences have been identified from humans, hamsters, Drosophila, Caenorhabditis elegans, and Arabidopsis. In a previous study, however, it was suggested that HSR1 had originated from a bacterial genome. HSR1 showed no detectible nucleotide sequence similarity to any eukaryotic sequences but harbored a protein coding region that showed amino-acid sequence similarity to bacterial voltage-gated chloride channel proteins. The bacterial origin of HSR1 was not convincible because the nucleotide sequence similarity was marginal. In this study, we have found that a genomic contig sequence of Comamonas testosteroni strain JL14 contained a sequence virtually identical to that of HSR1, decisively confirming the bacterial origin of HSR1. Thus, HSR1 is an exogenous RNA, which can ectopically trigger heat shock response in eukaryotes. Therefore, it is no longer appropriate to cite HSR1 as a "eukaryotic functional noncoding RNA."