• The Korean Journal of Zoology
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• v.35 no.2
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• pp.203-210
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• 1992

Hsp70, a 70 kDa protein, is the maior protein expressed when cells are heat-shocked. A cDNA library from mouse ID13 cells was screened with the human hsp70 gene as a probe, and a positive clone was obtained. The positive clone was subcloned into puc19 and the precise restriction was obtained. The CDNA was sequenced by the Sanger's dideoxv termination method. Single open reading frame that codes for a protein of 70 kDa was found. The DNA sequence of the cloned mouse DNA shows great homology (66-90%) with other mouse hsp70 genes and somewhat less homology (50",) with E. coli hsp70 gene (dnak). With the exception of one amino acid, the protein sequence deduced from the CDNA is identical to the mouse that shock cognate protein 70 (hsc70) that is constitutivelv expressed at normal temperature. The result suggests that the cloned CDNA encodes a hsc70 family rather than a heatinducible family.mily.

• The Korean Journal of Zoology
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• v.38 no.4
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• pp.557-564
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• 1995

The 90 kDa-heat shock protein (HSP90) is one of the major ubiquitous heat shock proteins induced by a vadety of ceilular stresses. HSP90 Is constitutively synthesized even under nonstressed condidons and found In association with several regulatory and structural proteins such as protein kinases and steroid hormone receptors. In the present study, to facilitate its biochemical characterization, HSP90 was pudfied from chick muscle by sequential column chromatography steps including DEAE- cellulose, hydroxyapatite, and Sephacryl S-300 gel filtration and monoclonal antillodies specific to HSP90 were produced by the inurine hybridomal technique. We report the production of 4 posItive hybridoma clones, named as A204, C112, C302 and A204, C112, C302. Among these MoAbs, Cl 12 strongly reconnized chick HSP90 in Western blot and native immunoprocipitation. In addition, C112 showed the crossreactivitles against HSP90 from human, rabbit, mouse, fish and chick but not from Drosophila and E. coil.

• Biomedical Science Letters
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• v.12 no.4
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• pp.419-425
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• 2006

Phospholipase $C-{\gamma}1\;(PLC-{\gamma}1)$ is an important signaling molecule for cell proliferation and differentiation. $PLC-{\gamma}1$ contains two pleckstrin homology (PH) domains, which are responsible for protein-protein interaction and protein-lipid interaction. $PLC-{\gamma}1$ also has two Src homology (SH)2 domains and a SH3 domain, which are responsible for protein- protein interaction. To identity proteins that specifically binds to PH domain of $PLC-{\gamma}1$, we prepared and incubated the glutathione S-transferase(GST)-fused PH domains of $PLC-{\gamma}1$ with COS7 cell lysate. We found that 90 kDa protein specifically binds to PH domain of $PLC-{\gamma}1$. By matrix-assisted laser desorption ionization time of flight-mass spectrometry, the 90 kDa protein revealed to be heat shock protein (Hsp) $90{\beta}$. Hsp $90{\beta}$ is a molecular chaperone that stabilizes and facilitates the folding of proteins that are involved in cell signaling, including receptors for steroids hormones and a variety of protein kinases. To know whether Hsp $90{\beta}$ affects on $PLC-{\gamma}1$ activity, we performed $PIP_2$ hydrolyzing activity of $PLC-{\gamma}1$ in the presence of purified Hsp $90{\beta}$ in vitro. Our results show that the Hsp $90{\beta}$ dose-dependently inhibits the enzymatic activity of $PLC-{\gamma}1$ and further suggest that Hsp $90{\beta}$ regulates cell growth and differentiation via regulation of $PLC-{\gamma}1$ activity.

• Journal of Microbiology
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• v.39 no.3
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• pp.162-167
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• 2001

Methylovorus sp. strain SS1 DSM 11726 was found to grow continuously when it was transferred from 30$\^{C}$ to 40$\^{C}$ and 43$\^{C}$. A shift in growth temperature from 30$\^{C}$ to 45$\^{C}$, 47$\^{C}$ and 50$\^{C}$ reduced the viability of the cell population by more than 10$^2$, 10$^3$and 10$\^$5/ folds, respectively, after 1h cultivation. Cells transferred to 47$\^{C}$ and 50$\^{C}$ after preincubation for 15 min at 43$\^{C}$, however, exhibited 10-fold increase in viability. It was found that incubation for 15 min at 40$\^{C}$ of Methylovorus sp. strain SSl grown at 30$\^{C}$ was sufficient to accelerate the synthesis of a specific subset of proteins. The major heat shock proteins had apparent molecular masses of 90, 70, 66, 60, and 58 kDA. The 60 and 58 kDa proteins were found to cross-react with the antiserum raised against GroEL protein. The heat shock response persisted for over 1h. The shock proteins were stable for 90 min in the cell. Exposure of the cells to methanol induced proteins identical to the heat shock proteins. Addition of ethanol induced a unique protein with a molecular mass of about 40 kDa in addition to the heat-induced proteins. The proteins induced in paraquat-treated cells were different from the heat shock proteins, except the 70 and 60 kDa proteins.

• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.269.1-269
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• 1999

No Abstract, See Full Text

• The Korean Journal of Zoology
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• v.39 no.2
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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.

• Korean Journal of Biological Psychiatry
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• v.6 no.2
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• pp.202-208
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• 1999

Schizophrenia has many clinical expressions and probably different etiologic factors. Infections, autoimmune mechanism and related neurodevelopmental abnormalities have been suggested as possible etiologic factors of schizophrenia. It has been reported that immunoreactivity to heat shock proteins, which play a protective role against environmental stresses in a cell, might be related to the pathogenesis of schizophrenia. Therefore, we examined the immunoreactivity to heat shock protein 70kDa and 90kDa(HSP70 and 90) in 91 patients with schizophrenia and 83 normal controls. Ig G antibodies to HSP70 and 90 of sera were quantitated by ELISA. The optical density(OD) was measured by an automated microplate reader at a wavelength of 490nm. The amounts of antibodies to HSPs were expressed as arbitrary units(AU)/ml related to a standard serum. The limit for elevated antibody titers(anti-HSPs positive or negative) was set at two standard deviations added to the mean of the normal controls. Twenty nine(31.9%) of the 91 patients showed anti-HSP70 positive and 19(20.9%) of those showed anti-HSP90 positive. On the other hand, only 1(1.4%) of the normal controls and 4(4.8%) of those showed anti-HSP70 positive and anti-HSP90 positive, respectively. The titers of anti-HSP70 positive were related with BPRS scores, while those of anti-HSP90 positive were not. There were no relationship between antibody titers and clinical variables including age at onset, duration of illness, family history of schizophrenia or number of admission. The titers of anti-HSP70 positive were significantly associated with anti-HSP90 positive. Our results suggest the presence of abnormal immune reactivity involving HSP70 and HSP90 in a subset of patients with schizophrenia.

• Molecules and Cells
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• v.24 no.2
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• pp.210-214
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• 2007

The 90-kDa heat shock protein (HSP90) normally functions as a molecular chaperone participating in folding and stabilizing newly synthesized proteins, and refolding denatured proteins. The HSP90 inhibitor geldanamycin (GA) occupies the ATP/ADP binding pocket of HSP90 so inhibits its chaperone activity and causes subsequent degradation of HSP90 client proteins by proteasomes. Here we show that GA reduces the level of endogenous c-Jun in human embryonic kidney 293 (HEK293) cells in a time and dose dependent manner, and that this decrease can be reversed by transfection of HSP90 plasmids. Transfection of HSP90 plasmids in the absence of GA increases the level of endogenous c-Jun protein, but has no obvious affect on c-Jun mRNA levels. We also showed that HSP90 prolongs the half-life of c-Jun by stabilizing the protein; the proteasome inhibitor N-benzoyloxycarbonyl (Z)-Leu-Leu-leucinal (MG132) blocks the degradation of c-Jun promoted by GA. Transfection of HSP90 plasmids did not obviously alter phosphorylation of c-Jun, and a Jun-2 luciferase activity assay indicated that over-expression of HSP90 elevated the total protein activity of c-Jun in HEK293 cells. All our evidence indicates that HSP90 stabilizes c-Jun protein, and so increases the total activity of c-Jun in HEK293 cells.

• Journal of Life Science
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• v.10 no.5
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• pp.533-541
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• 2000

Compared to mammal including human, many bioreactive genes that regulate various biological events has not been cloned and characterized yet in fishes, especially shark, Scyliorhinus torazame. In orther to isolate genes that regulate physiological processes in cartilaginors fishes, we performed reverse transcription-polymerase chain reaction (RT-PCR) using the RNA of cartilage tissues of Scyliofhinus torazame. The cloned partial genes were 86%, 80%, 73%, 84%, 75%, 79% identical to $\alpha$- actin, 90-kDa heat-shock protein, methyle-neterahydrofolate dehydrogenase-methenyltertrahydrofolate cyclohudrolase-formyltetrahydrofolate synthetase, ubiquitin, glutamine synthetase and connective tissue growth factor genes of human, respectively. They also have similar nucleotide sequence homologues with those of another species. These partial bioreactive genes elucidated in this study may support to studies of phylogenetic analysis based on evolutionary relationships between shark and other species.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.3
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• pp.354-361
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• 2015

Mitochondrial heat shock protein 75 (mtHSP75) is a member of the HSP90 family and plays essential roles in refolding proteins of the mitochondrial matrix. Mitochondria provide energy in the form of ATP and generate reactive oxygen species (ROS). Heat shock proteins (HSPs) are activated in response to stress, and protect cells. In this study, we characterized the mtHSP75 of the big-belly seahorse Hippocampus abdominalis. The protein (BsmtHSP75) is encoded by an open reading frame (ORF) of 2,157 nucleotides, has 719 amino acids (aa), and is of molecular mass 82 kDa. BsmtHSP75 has two functional domains, a histidine kinase-like ATPase (HATPase_c) domain (123-276 aa) and an HSP90 family domain (302-718 aa). BsmtHSP75 was expressed in all tested tissues of healthy seahorses. The ovary contained the highest transcription level, followed (in order) by the blood, brain, and muscle. Pouch tissue showed the lowest expression level. The expression of BsmtHSP75 was significantly (P<0.05) up-regulated on viral or bacterial challenge, suggesting that BsmtHSP75 plays a role in the immune defense against bacterial and viral pathogens.