• 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.

• Korean Journal of Poultry Science
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• v.40 no.1
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• pp.31-40
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• 2013

This study was performed to investigate the investigated effects of dietary supplementation of vitamin C and E on the growth performance and stress response in broiler chickens. Stress response was analyzed by the quantity of telomeric DNA, the rate of DNA damage and the expression levels of heat shock proteins (HSPs) and hydroxyl-3-methyl-glutaryl coenzyme A reductase (HMGCR) genes on tissues and blood. The telomere length and telomere shortening rates were analyzed by quantitative fluorescence in situ hybridization on the nuclei of lymphocytes and tissues. The DNA damage rate of lymphocytes was quantified by the comet assay. The expression levels of HSP70, HSP90s and HMGCR genes were measured by quantitative real-time polymerase chain reaction in lymphocytes. In results, there was no significant difference among treatments in body weight, weight gain, feed intake and mortality. The telomere shortening rate of the lymphocytes was significantly lower in the vitamin E supplemented group than the control group. The DNA damage was also decreased supplemented with vitamin C and E, as compared to the control group. The vitamin E supplemented group had a significant positive effect on the expressions of HMGCR, HSP90-${\alpha}$ and HSP90-${\beta}$ in lymphocytes, but had no significance on HSP70, as compared to the control group. We concluded that the dietary supplementation of vitamin E (100 mg/kg feed) had reduced the individual physiological stress response without stunt growth in broiler chickens.

• Journal of Microbiology and Biotechnology
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• v.24 no.7
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• pp.914-920
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• 2014

Triple-negative breast cancer (TNBC) possesses a higher rate of distant recurrence and a poorer prognosis than other breast cancer subtypes. Interestingly, most of the heat shock protein 90 (Hsp90) client proteins are oncoproteins, and some are closely related to unfavorable factors of TNBC patients. 17-Demethoxy-reblastatin (17-DR), a novel non-benzoquinone-type geldanamycin analog, exhibited potent Hsp90 ATPase inhibition activity. In this study, the anticancer effects of 17-DR on TNBC MDA-MB-231 cells were investigated. These results showed that 17-DR inhibited cell proliferation, induced apoptosis, and suppressed cell invasion and migration in the MDA-MB-231 cells. Down-regulation of the key Hsp90-dependent tumor-driving molecules, such as RIP1 and MMP-9, by 17-DR may be related to these effects. Taken together, our results suggest that 17-DR has potential as a therapeutic agent for the treatment of TNBC.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.1
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• pp.94-99
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• 2017

Objective: The aim of this study was to investigate the expression of heat shock protein (HSP) 90, 70, and 60 in chicken muscles and their possible relationship with quality traits of meat. Methods: The breast muscles from one hundred broiler chickens were analyzed for drip loss and other quality parameters, and the levels of heat shock protein (HSP) 90, 70, and 60 were determined by immunoblots. Results: Based on the data, chicken breast muscles were segregated into low (drip loss${\leq}5%$), intermediate (5%${\geq}9.5$) drip loss groups. The expression of HSP90 and HSP60 were significantly lower in the high drip loss group compared to that in the low and intermediate drip loss group (p<0.05), while HSP70 was equivalent in abundance in all groups (p>0.05). Conclusion: Results of this study suggests that higher levels of HSP90 and HSP60 may be advantageous for maintenance of cell function and reduction of water loss, and they could act as potential indicator for better water holding capacity of meat.

• 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.

• BMB Reports
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• v.50 no.5
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• pp.235-236
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• 2017

The circadian clock is an internal system that is synchronized by external stimuli, such as light and temperature, and influences various physiological and developmental processes in living organisms. In the model plant Arabidopsis, transcriptional, translational and post-translational processes are interlocked by feedback loops among morning- and evening-phased genes. In a post-translational loop, plant-specific single-gene encoded GIGANTEA (GI) stabilize the F-box protein ZEITLUPE (ZTL), driving the targeted-proteasomal degradation of TIMING OF CAB EXPRESSION 1 (TOC1) and PSEUDO-RESPONSE REGULATOR 5 (PRR5). Inherent to this, we demonstrate the novel biochemical function of GI as a chaperone and/or co-chaperone of Heat-Shock Protein 90 (HSP90). GI prevents ZTL degradation as a chaperone and facilitates ZTL maturation together with HSP90/HSP70, enhancing ZTL activity in vitro and in planta. GI is known to be involved in a wide range of physiology and development as well as abiotic stress responses in plants, but it could also interact with diverse client proteins to increase protein maturation. Our results provide evidence that GI helps proteostasis of ZTL by acting as a chaperone and a co-chaperone of HSP90 for proper functioning of the Arabidopsis circadian clock.

• Bulletin of the Korean Chemical Society
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• v.34 no.6
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• pp.1917-1920
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• 2013

• Reproductive and Developmental Biology
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• v.35 no.3
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• pp.307-311
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• 2011

Heat shock protein 90 (Hsp90) is ATPase-directed molecular chaperon and affects survival of several cells. In our previous study, inhibitory effect of Hsp90 by inducing cell cycle arrest and apoptosis in the pig embryonic and primary cells was reported. However, its role during early bovine embryonic development is not sufficient. In this study, we traced the effects of Hsp90 inhibitor, 17-allylamino-17-demethoxygeldanamycin (17-AAG), on early bovine embryonic development. We also investigated several indicators of developmental potential, including structural integrity, gene expression (apoptosis-related genes), and apoptosis, which are affected by 17-AAG. Bovine embryos were cultured in the CR1-aa medium with or without 17-AAG for 7 days. In result, significant differences in developmental potential were detected between the embryos that were cultured with or without 17-AAG ($33.1{\pm}9.6$ vs $21.7{\pm}8.3%$). The structural integrity of the blastocysts was examined by differential staining. Blastocysts from the dbcAMP-treated group had higher numbers of ICM, TE, and total cells than those from the untreated group. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) showed that the number of containing fragmented DNA at the blastocyst stage increased in the 17-AAG treated group compared with control (11.2 vs 3.9, respectively). Blastocysts that developed in the 17-AAG treated group had low structural integrity and high apoptotic nuclei than those of the untreated control, resulting in decrease the embryonic qualities of preimplantation bovine blastocysts. The mRNA expression of the pro-apoptotic gene (Bax) increased in 17-AAG treated group, whereas expression of the antiapoptotic gene (Bcl-XL) decreased. In conclusion, Hsp90 also appears to play a direct role in bovine early embryo developmental competence including structural integrity of blastocysts. Also, these results indicate that Hsp90 is closely associated with apoptosis-related genes expression in developing bovine embryos.

• Reproductive and Developmental Biology
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• v.35 no.1
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• pp.33-45
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• 2011

Heat shock protein 90 (Hsp90) is ATPase-directed molecular chaperon and affects survival of cancer cell. Inhibitory effect of Hsp90 by inducing cell cycle arrest and apoptosis in the cancer cell was reported. However, its role during oocyte maturation and early embryo development is very insufficient. In this study, we traced the effects of Hsp90 inhibitor, 17-allylamino-17-demethoxygeldanamycin (17-AAG), on meiotic maturation and early embryonic development in pigs. We also investigated several indicators of developmental potential, including structural integrity, gene expression (Hsp90-, cell cycle-, and apoptosis-related genes), and apoptosis, which are affected by 17-AAG. Then, we examined the roles of Hsp90 inhibitor on viability of primary cells in pigs. Porcine oocytes were cultured in the NCSU-23 medium with or without 17-AAG for 44 h. The proportion of GV arrested oocytes was significantly different between the 17-AAG treated and untreated group (78.2 vs 34.8%, p<0.05). After completion of meiotic maturation, the proportion of MII oocytes was lower in the 17-AAG treated group than in the control group (27.9 vs 71.0%, p<0.05). After IVF, the percentage of penetrated oocytes was significantly lower in the 17-AAG treated group (25.2%), resulting in lower normal pronucleus formation (2PN of 14.6%). Therefore, the inhibition of meiotic progression by Hsp90 inhibitor played a critical role in fertilization status. Porcine embryo were cultured in the PZM-3 medium with or without 17-AAG for 6 days. In result, significant differences in developmental potential were detected between the embryos that were cultured with or without 17-AAG. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) showed that the number of containing fragmented DNA at the blastocyst stage increased in the 17-AAG treated group compared with control (7.5 vs 4.4, respectively). Blastocysts that developed in the 17-AAG treated group had low structural integrity and high apoptotic nuclei than those of the untreated control, resulting in decrease the embryonic qualities of preimplantation porcine blastocysts. The mRNA expressions of cell cycle-related genes were down-regulated in the 17-AAG treated group compared with control. Also, the expression of the pro-apoptotic gene Bax increased in 17-AAG treated group, whereas expression of the anti-apoptotic gene Bel-XL decreased. However, the expression of ER stress-related genes did not changed by 17-AAG. Cultured pESF cells were treated with or without 17-AAG and used for MIT assay. The results showed that viability of pESF cells were decreased by treatment of 17-AAG ($2{\mu}M$) for 24 hr. These results indicated that 17-AAG decreased cell proliferation and increased cell death. Expression patterns Hsp90 complex genes (Hsp70 and p23), cell cycle-related genes (cdc2 and cdc25c) and apoptosis-related genes (Bax and Bcl-XL) were significantly changed by using RT-PCR analysis. The spliced form of pXbp-1 product (pXbp-1s) was detected in the tunicamycin (TM) treated cells, but it is not detected in 17-AAG treated cells. In conclusion, Hsp90 appears to play a direct role in porcine early embryo developmental competence including structural integrity of blastocysts. Also, these results indicate that Hsp90 is closely associated with cell cycle- and apoptosis-related genes expression in developing porcine embryos.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.3929-3937
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• 2016

Gastric cancer (GC) is a major health problem worldwide and is one of the ten most commonly diagnosed cancers in Jordan. GC is usually diagnosed at late aggressive stages in which treatment options are limited. Recently, heat shock proteins (HSPs) were found to be overexpressed in a wide range of malignancies have been considered as promising candidate biomarkers for GC. The aim of this study was to investigate pathogenic roles of a panel of cytosolic HSPs including HSP90, HSP70, HSP60 and HSP27 in GC. Immunohistochemistry was used to assess the level of expression of these proteins in archived tumor samples (N=87) representing various pathological characteristics of GC. HSP90, HSP60 and HSP27 were expressed abundantly in gastric tumors. On the other hand, HSP70 was reduced significantly and also found to be associated with Helicobacter pylori infection in tissues collected from GC patients. Furthermore, HSP27 was found to be associated with the level of differentiation. Our findings indicate a role of HSP70 as a potential prognostic biomarker, patients harboring positive HSP70 expression displaying worse disease free survival than those with negative HSP70 expression. Differential expression of HSPs may play crucial roles in the initiation and progression of GC, and could be exploited as future therapeutic targets.