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Heat Shock Protein (heat + shock_protein)
Kinds of Heat Shock Protein Terms modified by Heat Shock Protein Selected AbstractsNEW INSIGHT INTO THE SIGNALLING PATHWAYS OF HEAT STRESS-INDUCED MYOCARDIAL PRECONDITIONING: PROTEIN KINASE C, TRANSLOCATION AND HEAT SHOCK PROTEIN 27 PHOSPHORYLATIONCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 3 2004Claire Arnaud SUMMARY 1.,Heat stress (HS) is known to induce delayed preconditioning against myocardial infarction 24 h later, but the exact signalling pathway of this response remains to be elucidated. In previous studies, we have shown evidence for the implication of protein kinase C (PKC) and p38 mitogen-activated protein kinase (MAPK) in the HS-induced reduction in infarct size. Furthermore, in their phosphorylated state, small heat shock proteins (Hsp27) seem to confer cytoskeletal protection. In the present study, we sought to determine the effect of HS on the subcellular distribution of PKC isoforms and on Hsp27 phosphorylation. 2.,Rats were subjected to either HS (42°C for 15 min; HS group) or sham anaesthesia (sham group) before their hearts were excised. Myocardial tissue extracts obtained 20 min or 24 h after HS were processed for western blot analysis. 3.,In the HS group, PKC, translocated from the cytosolic to the particulate fraction (4426 ± 128 vs 6258 ± 316 arbitrary units; P = 0.002). Chelerythrine (5 mg/kg, i.p.), a PKC inhibitor, abolished this translocation. Western blot analysis of Hsp27 24 h after HS showed a marked increase in protein expression and phosphorylation in the particulate fraction. 4.,In the present study, we have shown that HS induces the translocation of PKC, from the cytosolic to the particulate fraction. Along with our previous observation that PKC is a trigger of HS-induced myocardial preconditioning, the results of the present study suggest an important role of the , isoform of PKC in this cardioprotective mechanism. Furthermore, we have also demonstrated that the cytoprotective protein Hsp27 is phosphorylated following HS. Therefore, we can conclude that PKC and MAPK/Hsp27 are involved in the signalling pathway of HS-induced cardioprotection. [source] Heat Shock Protein in Developing Grains in Relation to Thermotolerance for Grain Growth in WheatJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 1 2010P. Sharma-Natu Abstract Wheat (Triticum aestivum L.) cvs DL 153-2 and HD 2285 (relatively tolerant), HD 2329 and WH 542 (relatively susceptible), were grown under normal (27 November) and late (28 December) sown conditions. In another experiment, these cultivars were grown under normal sowing and at anthesis stage, they were transferred to control (C) and heated (H) open top chambers (OTCs). Under late sowing, wheat cultivars were exposed to a mean maximum temperature of up to 3.6 °C higher than normal sowing and in H-OTCs, mean maximum temperature was 3.2 °C higher than C-OTCs during grain growth period. Heat susceptibility index (S) for grain growth and grain yield was determined at maturity in both the experiments. The level of heat shock protein (HSP 18) in the developing grains was determined in C- and H-OTC grown plants and in normal and late sown plants by Western blot analysis. The moderately high temperature exposure increased the accumulation of HSP 18 in the developing grains. The relatively tolerant cultivars, as also revealed from S, showed a greater increase in HSP 18 compared with susceptible types in response to moderate heat stress. An association of HSP 18 with thermotolerance for grain growth in wheat was indicated. [source] Muscle Endurance in Elderly Nursing Home Residents Is Related to Fatigue Perception, Mobility, and Circulating Tumor Necrosis Factor-Alpha, Interleukin-6, and Heat Shock Protein 70JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 3 2008(See editorial comments by Drs. Hermes Florez, Bruce R. Troen, pp 55 OBJECTIVES: To explore the relationships between muscle endurance and circulating interleukin (IL)-6, tumor necrosis factor alpha (TNF-,), and heat shock protein (Hsp)70 in nursing home residents and to assess how muscle endurance relates to self-perceived fatigue and mobility. DESIGN: Exploratory study. SETTING: Three nursing homes of the Foundation for Psychogeriatrics (Brussels, Belgium). PARTICIPANTS: Seventy-seven residents (53 female and 24 male, mean age 81 ± 8). MEASUREMENTS: Participants were assessed for muscle endurance (fatigue resistance and grip work); perceived fatigue (visual analogue scale for fatigue); fatigue during daily activities (Mobility-Tiredness Scale); effect of fatigue on quality of life (World Health Organization Quality Of Life questionnaire); mobility (Tinetti Test & Elderly Mobility Scale (EMS)); and circulating IL-6, TNF-,, and Hsp70. RESULTS: Residents with better fatigue resistance reported less self-perceived tiredness (P<.05). Similar trends were observed for fatigue during daily activities and for the extent to which fatigue bothered subjects. Higher grip work was associated with less self-perceived fatigue on all fatigue scales (P<.01). Fatigue resistance and grip work were positively related to balance and basic mobility (all P<.01; trend for relationship between fatigue resistance and EMS). Subjects with high IL-6 and Hsp70 showed significantly worse fatigue resistance (P=.007) and muscle work (P=.045) than those with high IL-6 and low Hsp70. In male residents, higher TNF-, was related to worse fatigue resistance and grip work (P<.05). CONCLUSION: Elderly nursing home residents complaining of fatigue need to be taken seriously, because they show worse muscle endurance, which is related to poorer mobility. Inflammatory processes involving TNF-, and the interaction between IL-6 and Hsp70 are related to poorer muscle endurance in these patients. [source] Molecular and immunological characterization of the C-terminal region of a new Echinococcus granulosus Heat Shock Protein 70PARASITE IMMUNOLOGY, Issue 3 2003E. Ortona SUMMARY By screening an expression library of Echinococcus granulosus with IgE from sera of patients with cystic echinococcosis (CE) and allergic reactions, we isolated the C-terminal region of a new heat shock protein (HSP)70 of E. granulosus. The protein, named Eg2HSP70, has close homology with the C-terminal region of Dermatophagoides farinae and human HSP70. We investigated the humoral and cell-mediated immune responses to this antigen in patients with CE grouped according to the presence of allergic reactions. Immunoblotting detected total IgG, IgG4 and IgE specific to Eg2HSP70 (83% of sera contained IgG, 31% IgG4 and 57% IgE). No significant difference was found in immunoglobulin percentages according to the presence of allergic reactions. Immunoblotting inhibition showed that no IgG or IgE specific to Eg2HSP70 cross-reacted with D. farinae or human HSP70. Eg2HSP70-stimulated PBMC from 26 patients produced significantly greater amounts of TNF-,, IFN-,, and IL-10 than unstimulated cultures in all patients, irrespective of the presence of allergic reactions (P < 0·05). They also produced significantly greater amounts of IL-4 than unstimulated cultures exclusively in patients with allergic reactions (P < 0·05). These findings show that Eg2HSP70 is a new antigenic molecule inducing both B and T cell responses. [source] Heat Shock Protein 70 and Sex Steroid Receptors in the Follicular Structures of Induced Ovarian CystsREPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2009NR Salvetti Contents The purpose of this study was to estimate the expression and relative amounts of estrogen (ER) and progesterone receptors (PR) and their isoforms as well as heat shock protein 70 (HSP70) in ovaries of rats with induced cystic ovarian disease (COD). Primary, secondary, tertiary, atretic and cystic follicles were evaluated by immunohistochemistry and total ovarian proteins were analyzed by Western blot. In the granulosa layer, growing and cystic follicles in the treated group have a higher expression of ER, than growing follicles of control individuals. In the theca interna layer, tertiary follicles presented a significantly higher expression of ER, in the treated group. An increase in total ER, protein was detected in the treated group. Granulosa cells of all growing, atretic and cystic follicles show a lower expression of ER, in animals with COD, and the total protein expression of ER, was lower in this group. The expression of PR was lower in the granulosa cell layer of tertiary and cystic follicles in treated animals, and theca interna layer had less intense immunostaining in this group. Although there were no differences in the expression of PR-B by Western blotting, the expression of PR-A was higher and the expression of PR-C was smaller in the treated group. An intense HSP70 immunostaining was observed in the cells of cystic follicles. By Western blotting, higher protein expression of HSP70 was detected in the ovarian samples of the control group than those of the treated ones. Ovaries of animals with COD exhibited an altered steroid receptor expression and subtype balance as compared with control animals, and an increase in HSP70 immunoexpression. [source] Anti,Heat Shock Protein 70 Antibodies in Meniere's Disease ,THE LARYNGOSCOPE, Issue 9 2000Steven D. Rauch MD Abstract Objectives To determine the prevalence of anti,heat shock protein 70 (anti-HSP70) antibodies in patients with Meniere's disease and healthy subjects and to probe the relationship between antibody status and clinical features of Meniere's disease. Study Design Prospective cohort study of consecutive consenting patients with Meniere's disease. Methods Serum samples were obtained prospectively from 134 patients with Meniere's disease and 124 blood donors. Serial samples were taken at 3-month intervals in 38 of 134 patients with Meniere's disease. Demographic data and clinical characterization of vestibular and auditory status were acquired with each sample. Serum was assayed for anti-HSP70 antibodies by Western blot using bovine renal extract, recombinant bovine HSP70, and recombinant human HSP70 antigens. Results Immunoreactivity against bovine renal extract HSP70 was found in 38% of patients with Meniere's disease, compared with 25% of blood donors (P < .04). Reactivity with recombinant antigens was not significantly different between patients with Meniere's disease and healthy control subjects. Patients with Meniere's disease who reacted with all three antigens were more likely to have simultaneously active hearing and balance symptoms (P = .03). Neither univariate nor multivariate statistical analysis established any other association between serological findings and clinical features of Meniere's disease. Tests performed on serial samples of patients with Meniere's disease also showed no association of positive or negative test results with changes in clinical course. Conclusions Because of the high prevalence of anti-HSP70 antibodies in healthy subjects and the very limited association of anti-HSP70 antibody status with clinical features or course of Meniere's disease, we conclude that, at present, the detection of anti-HSP70 antibodies by Western blotting offers little clinically useful information in Meniere's disease. [source] Cognate Hsp70 gene is induced during deep larval diapause in the moth Sesamia nonagrioidesINSECT MOLECULAR BIOLOGY, Issue 2 2009T. Gkouvitsas Abstract The complete cDNA sequences of Heat shock cognate protein 70 (SnoHsc70) and Heat shock protein 70 (SnoHsp70) were determined from the corn stalk borer Sesamia nonagrioides (Lef.). They encode 653 amino acids (Hsc70) and 633 amino acids (Hsp70), with calculated molecular masses of 71.5 kDa and 70.2 kDa respectively. SnoHsc70 is constitutively expressed, and SnoHsp70 is heat-inducible in non-diapausing insects. SnoHsp70 is down regulated during diapause, while SnoHsc70 is induced as the larvae enter deep diapause. High temperature stress during diapause has no further effect on transcript levels of SnoHsc70. Our results show that SnoHsc70 may play important roles in assisting protein conformation during specific stages of diapause. [source] Transcriptional upregulation of HSP70-2 by HIF-1 in cancer cells in response to hypoxiaINTERNATIONAL JOURNAL OF CANCER, Issue 2 2009Wen-Jie Huang Abstract Heat shock protein 70-2 (HSP70-2) can be expressed by cancer cells and act as an important regulator of cancer cell growth and survival. Here, we show the molecular mechanisms by which hypoxia regulate HSP70-2 expression in cancer cells. When cells were subjected to hypoxia (1% O2), the expression of HSP70-2 had a significant increase in cancer cells. Such increase was due to the direct binding of hypoxia-inducible factor to hypoxia-responsive elements (HREs) in the HSP70-2 promoter. By luciferase assays, we demonstrated that the HRE1 at position ,446 was essential for transcriptional activation of HSP70-2 promoter under hypoxic conditions. We also demonstrated that HIF-1, binds to the HSP70-2 promoter and the binding is specific, as revealed by HIF binding/competition and chromatin immunoprecipitation assays. Consequently, the upregulation of HSP70-2 enhanced the resistance of tumor cells to hypoxia-induced apoptosis. These findings provide a new insight into how tumor cells overcome hypoxic stress and survive, and also disclose a new regulatory mechanism of HSP70-2 expression in tumor cells. © 2008 Wiley-Liss, Inc. [source] Heat shock protein 27: its potential role in vascular diseaseINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 4 2006Gordon Ferns Summary Heat shock proteins are molecular chaperones that have an ability to protect proteins from damage induced by environmental factors such as free radicals, heat, ischaemia and toxins, allowing denatured proteins to adopt their native configuration. Heat shock protein-27 (Hsp27) is a member of the small Hsp (sHsp) family of proteins, and has a molecular weight of approximately 27 KDa. In addition to its role as a chaperone, it has also been reported to have many additional functions. These include effects on the apoptotic pathway, cell movement and embryogenesis. In this review, we have focused on its possible role in vascular disease. [source] Hepatic effects of an open lung strategy and cardiac output restoration in an experimental lung injuryACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2010M. KREDEL Background: Ventilation with high positive end-expiratory pressure (PEEP) can lead to liver dysfunction. We hypothesized that an open lung concept (OLC) using high PEEP impairs liver function and integrity dependent on the stabilization of cardiac output. Methods: Juvenile female Pietrain pigs instrumented with flow probes around the common hepatic artery and portal vein, pulmonary and hepatic vein catheters underwent a lavage-induced lung injury. Ventilation was continued with a conventional approach (CON) using pre-defined combinations of PEEP and inspiratory oxygen fraction or with an OLC using PEEP set above the lower inflection point of the lung. Volume replacement with colloids was guided to maintain cardiac output in the CON(V+) and OLC(V+) groups or acceptable blood pressure and heart rate in the OLC(V,) group. Indocyanine green plasma disappearance rate (ICG-PDR), blood gases, liver-specific serum enzymes, bilirubin, hyaluronic acid and lactate were tested. Finally, liver tissue was examined for neutrophil accumulation, TUNEL staining, caspase-3 activity and heat shock protein 70 mRNA expression. Results: Hepatic venous oxygen saturation was reduced to 18 ± 16% in the OLC(V,) group, while portal venous blood flow decreased by 45%. ICG-PDR was not reduced and serum enzymes, bilirubin and lactate were not elevated. Liver cell apoptosis was negligible. Liver sinusoids in the OLC(V+) and OLC(V,) groups showed about two- and fourfold more granulocytes than the CON(V+) group. Heat shock protein 70 tended to be higher in the OLC(V,) group. Conclusions: Open lung ventilation elicited neutrophil infiltration, but no liver dysfunction even without the stabilization of cardiac output. [source] Effect of methylglyoxal modification and phosphorylation on the chaperone and anti-apoptotic properties of heat shock protein 27JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 1 2006Tomoko Oya-Ito Abstract Heat shock protein 27 (Hsp27) is a stress-inducible protein in cells that functions as a molecular chaperone and also as an anti-apoptotic protein. Methylglyoxal (MGO) is a reactive dicarbonyl compound produced from cellular glycolytic intermediates that reacts non-enzymatically with proteins to form products such as argpyrimidine. We found considerable amount of Hsp27 in phosphorylated form (pHsp27) in human cataractous lenses. pHsp27 was the major argpyrimidine-modified protein in brunescent cataractous lenses. Modification by MGO enhanced the chaperone function of both pHsp27 and native Hsp27, but the effect on Hsp27 was at least three-times greater than on pHsp27. Phosphorylation of Hsp27 abolished its chaperone function. Transfer of Hsp27 using a cationic lipid inhibited staurosporine (SP)-induced apoptotic cell death by 53% in a human lens epithelial cell line (HLE B-3). MGO-modified Hsp27 had an even greater effect (62% inhibition). SP-induced reactive oxygen species in HLE-B3 cells was significantly lower in cells transferred with MGO-modified Hsp27 when compared to native Hsp27. In vitro incubation experiments showed that MGO-modified Hsp27 reduced the activity of caspase-9, and MGO-modified pHsp27 reduced activities of both caspase-9 and caspase-3. Based on these results, we propose that Hsp27 becomes a better anti-apoptotic protein after modification by MGO, which may be due to multiple mechanisms that include enhancement of chaperone function, reduction in oxidative stress, and inhibition of activity of caspases. Our results suggest that MGO modification and phosphorylation of Hsp27 may have important consequences for lens transparency and cataract development. J. Cell. Biochem. © 2006 Wiley-Liss, Inc. [source] Heat shock protein 27 is involved in neurite extension and branching of dorsal root ganglion neurons in vitroJOURNAL OF NEUROSCIENCE RESEARCH, Issue 4 2006Kristy L. Williams Abstract Alteration of the cytoskeleton in response to growth factors and extracellular matrix proteins is necessary for neurite growth. The cytoskeletal components, such as actin and tubulin, can be modified through interaction with other cellular proteins, including the small heat shock protein Hsp27. Our previous work suggested that Hsp27 influences neurite growth, potentially via its phosphorylation state interactions with actin. To investigate further the role of Hsp27 in neurite outgrowth of adult dorsal root ganglion (DRG) neurons, we have both down-regulated endogenous Hsp27 and expressed exogenous Hsp27. Down-regulation of Hsp27 with Hsp27 siRNA resulted in a decrease of neuritic tree length and complexity. In contrast, expression of exogenous Hsp27 in these neurons resulted in an increase in neuritic tree length and branching. Collectively, these results demonstrate that Hsp27 may play a role in neuritic growth via modulation of the actin cytoskeleton. © 2006 Wiley-Liss, Inc. [source] Morphological and molecular changes in denture-supporting tissues under persistent mechanical stress in ratsJOURNAL OF ORAL REHABILITATION, Issue 12 2008M. TSURUOKA Summary, The purpose of this study was to determine the effects of mechanical compression on the palatal mucosa using an experimental palatal base. The palatal base was either pressed onto (stress group) or not pressed onto (fit group) rat palatal mucosa. Blood flow was measured and the animals were sacrificed 6,72 h later for analysis. The expression of heat shock protein 70 (HSP70), vascular endothelial growth factor (VEGF) and proliferation cell nuclear antigen (PCNA) was characterized by immunohistochemical staining. For morphometric analysis, connective tissues were divided into bone side and epithelial side tissues. The ratio of PCNA-positive cells (PCNA score) was calculated, and the expressions of mRNA encoding HSP70 and VEGF was evaluated. Whereas blood flow in the stress group showed ischaemia, none was found in the fit group. Proliferation cell nuclear antigen scores on the bone side were higher than on the epithelial side in the stress group (P < 0·05). Heat shock protein 70- and VEGF-positive cells were observed under compression conditions, particularly in the periosteum. In the stress group, the expressions of mRNA encoding HSP70 and VEGF were highest at 12 h (P < 0·05). These results suggest that mechanical compression of the palatal plate induces ischaemia, and that cells in the underlying denture-supporting tissue, which includes the periosteum, synthesize HSP70 and VEGF to maintain homeostasis under these conditions. [source] The upregulation of heat shock protein 47 in human gingival fibroblasts stimulated with cyclosporine AJOURNAL OF PERIODONTAL RESEARCH, Issue 3 2010T.-Y. Chang Chang T-Y, Tsai C-H, Chang Y-C. The upregulation of heat shock protein 47 in human gingival fibroblasts stimulated with cyclosporine A. J Periodont Res 2010; 45: 317,322. © 2009 John Wiley & Sons A/S Background and Objective:, Heat shock protein 47 (Hsp47), a collagen-specific molecular chaperone, is involved in the processing and/or secretion of procollagen. Heat shock protein 47 is consistently and dramatically upregulated in a variety of fibrotic diseases. The aim of this study was to compare Hsp47 expression in normal gingival tissues and cyclosporine A-induced gingival overgrowth specimens and further explore the potential mechanisms that may lead to induction of Hsp47 expression. Material and Methods:, Fifteen cyclosporine A-induced gingival overgrowth specimens and five normal gingival tissues were examined by immunohistochemistry. Western blot was used to investigate the effects of cyclosporine A on the expression of Hsp47 in human gingival fibroblasts. In addition, Aggregatibacter actinomycetemcomitans, interleukin-1, (IL-1,) and mitogen-activated protein kinase kinase (MEK) inhibitor U0126 were added to seek the possible regulatory mechanisms of Hsp47 expression. Results:, A significantly higher percentage of cells positively stained for Hsp47 was noted in the cyclosporine A-induced gingival overgrowth group than in the normal gingival group (p < 0.05). Expression of Hsp47 was observed mainly in the cytoplasm of fibroblasts, endothelial cells, epithelial cells and inflammatory cells. Expression of Hsp47 was significantly higher in cyclosporine A-induced gingival overgrowth specimens with higher levels of inflammatory infiltrates (p < 0.05). Cyclosporine A upregulated Hsp47 expression in human gingival fibroblasts in a dose-dependent manner (p < 0.05). The addition of A. actinomycetemcomitans or interlukin-1, significantly increased Hsp47 expression compared with cyclosporine A alone (p < 0.05). The MEK inhibitor U0126 was found to inhibit cyclosporine A-induced Hsp47 expression (p < 0.05). Conclusion:, Expression of Hsp47 is significantly upregulated in cyclosporine A-induced gingival overgrowth specimens, and Hsp47 expression induced by cyclosporine A in fibroblasts may be mediated by the MEK signal transduction pathway. The expression of Hsp47 could be significantly enhanced by A. actinomycetemcomitans and interlukin-1,. [source] Porphyromonas gingivalis heat shock protein vaccine reduces the alveolar bone loss induced by multiple periodontopathogenic bacteriaJOURNAL OF PERIODONTAL RESEARCH, Issue 1 2006Ju-Youn Lee Objectives:, Heat shock protein (HSP) can be utilized as a vaccine to cross-protect against multiple pathogenic species. The present study was performed to evaluate Porphyromonas gingivalis heat shock protein 60 (HSP60) as a vaccine candidate to inhibit multiple bacteria-induced alveolar bone loss. Material and methods:, Recombinant P. gingivalis HSP60 was produced and purified from P. gingivalis GroEL gene. Rats were immunized with P. gingivalis HSP60, and experimental alveolar bone loss was induced by infection with multiple periodontopathogenic bacteria. Results:, There was a very strong inverse relationship between postimmune anti- P. gingivalis HSP immunoglobulin G (IgG) levels and the amount of alveolar bone loss induced by either P. gingivalis or multiple bacterial infection (p = 0.007). Polymerase chain reaction data indicated that the vaccine successfully eradicated the multiple pathogenic species. Conclusions:, We concluded that P. gingivalis HSP60 could potentially be developed as a vaccine to inhibit periodontal disease induced by multiple pathogenic bacteria. [source] Heat shock protein 47 is a new candidate molecule as anti-fibrotic treatment of Crohn's diseaseALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 8 2010H. Nakase No abstract is available for this article. [source] Heat shock protein 47 is a new candidate molecule as anti-fibrotic treatment of Crohn's disease: authors' replyALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 8 2010H. Szabò No abstract is available for this article. [source] Heat shock protein 101 effects in A. thaliana: genetic variation, fitness and pleiotropy in controlled temperature conditionsMOLECULAR ECOLOGY, Issue 6 2008S. J. TONSOR Abstract The Hsp100/ClpB heat shock protein family is ancient and required for high temperature survival, but natural variation in expression and its phenotypic effects is unexplored in plants. In controlled environment experiments, we examined the effects of variation in the Arabidopsis cytosolic AtHsp101 (hereafter Hsp101). Ten wild-collected ecotypes differed in Hsp101 expression responses across a 22 to 40 °C gradient. Genotypes from low latitudes expressed the least Hsp101. We tested fitness and pleiotropic consequences of varying Hsp101 expression in ,control' vs. mild thermal stress treatments (15/25 °C D/N vs. 15/25° D/N plus 3 h at 35 °C 3 days/week). Comparing wild type and null mutants, wt Columbia (Col) produced ~33% more fruits compared to its Hsp101 homozygous null mutant. There was no difference between Landsberg erecta null mutant NIL (Ler) and wt Ler; wt Ler showed very low Hsp101 expression. In an assay of six genotypes, fecundity was a saturating function of Hsp101 content, in both experimental treatments. Thus, in addition to its essential role in acquired thermal tolerance, Hsp101 provides a substantial fitness benefit under normal growth conditions. Knocking out Hsp101 decreased fruit production, days to germination and days to bolting, total dry mass, and number of inflorescences; it increased transpiration rate and allocation to root mass. Root : total mass ratio decayed exponentially with Hsp101 content. This study shows that Hsp101 expression is evolvable in natural populations. Our results further suggest that Hsp101 is primarily an emergency high-temperature tolerance mechanism, since expression levels are lower in low-latitude populations from warmer climates. Hsp101 expression appears to carry an important trade-off in reduced root growth. This trade-off may select for suppressed expression under chronically high temperatures. [source] Altered mRNA expression patterns in bovine blastocysts after fertilisation in vitro using flow-cytometrically sex-sorted spermMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 8 2007K.M. Morton Abstract Sperm-sexing has been used to produce embryos and offspring of a pre-determined sex in a number of species. However, the fertility of sex-sorted sperm is reduced and the full effects of sperm-sexing remain to be elucidated. The purpose of the present study was to investigate the potential effects of sex-sorted sperm on mRNA expression patterns of developmentally important genes employing in vitro produced bovine embryos. Bovine embryos were produced in vitro with unsorted and sex-sorted sperm and mRNA expression patterns were determined for glucose-3 transporter (Glut-3), glucose-6-phosphate dehydrogenase (G6PD), X-inactive specific transcript (X-ist) and Heat shock protein 70.1 (Hsp) using semi-quantitative endpoint reverse transcriptase-PCR in male and female, day-7 and 8 embryos. The relative abundance (RA) of Glut-3 was higher for day-7 male than female embryos, and day-7 embryos derived from unsorted compared with sex-sorted sperm. The RA of G6PD was higher for embryos derived from unsorted than sex-sorted sperm, and for day-8 female compared with male embryos. The RA of Xist was higher for female than male embryos, and for day-7 female embryos derived from unsorted than sex-sorted sperm. Hsp RA was higher for female compared with male embryos, was similar for day-7 and 8 embryos, and unsorted and sex-sorted sperm derived embryos. These results demonstrate differential expression of developmentally important genes between male and female embryos, and embryos derived from unsorted and sex-sorted sperm. Mol. Reprod. Dev. 74: 931,940, 2007. © 2007 Wiley-Liss, Inc. [source] Role of heat shock protein 47 on tubulointerstitium in experimental radiation nephropathyPATHOLOGY INTERNATIONAL, Issue 5-6 2002Diange Liu The molecular mechanisms of fibrosis in radiation nephropathy have received scant attention. Heat shock protein 47 (HSP47), a collagen-binding stress protein, helps in the intracellular processing of procollagen molecules during collagen synthesis. We investigated the role of HSP47 in the progression of radiation nephropathy using experimental radiation nephropathy. Experimental rat groups were as follows: (i) group I, sham operated (n = 12); (ii) group II, single doses of irradiation, either 7, 15 or 25 Gy to left kidney (n = 60); and (iii) group III, a similar irradiation procedure as group II after right nephrectomy (n = 60). The rats were followed up until 9 months after renal exposure to radiation. Renal dysfunction (as determined by serum creatinine and blood urea nitrogen) and hypertension were noted in group III rats, along with inflammatory cell infiltration and interstitial fibrosis (as determined by increased deposition of collagens). Compared to control rat kidneys, an increased expression of HSP47 was noted in kidneys obtained from irradiated rats. By double immunostaining, HSP47-expressing cells were identified as ,-smooth muscle actin-positive myofibroblasts and vimentin-positive tubular epithelial cells. Increased expression of HSP47 was closely associated with increased deposition of collagens in the widened interstitium of irradiated rats. Overexpression of HSP47 by phenotypically altered tubulointerstitial cells might play a role in excessive assembly/synthesis of collagens and could contribute to tubulointerstitial fibrosis in radiation nephropathy. [source] Not all J domains are created equal: Implications for the specificity of Hsp40,Hsp70 interactionsPROTEIN SCIENCE, Issue 7 2005Fritha Hennessy Abstract Heat shock protein 40s (Hsp40s) and heat shock protein 70s (Hsp70s) form chaperone partnerships that are key components of cellular chaperone networks involved in facilitating the correct folding of a broad range of client proteins. While the Hsp40 family of proteins is highly diverse with multiple forms occurring in any particular cell or compartment, all its members are characterized by a J domain that directs their interaction with a partner Hsp70. Specific Hsp40,Hsp70 chaperone partnerships have been identified that are dedicated to the correct folding of distinct subsets of client proteins. The elucidation of the mechanism by which these specific Hsp40,Hsp70 partnerships are formed will greatly enhance our understanding of the way in which chaperone pathways are integrated into finely regulated protein folding networks. From in silico analyses, domain swapping and rational protein engineering experiments, evidence has accumulated that indicates that J domains contain key specificity determinants. This review will critically discuss the current understanding of the structural features of J domains that determine the specificity of interaction between Hsp40 proteins and their partner Hsp70s. We also propose a model in which the J domain is able to integrate specificity and chaperone activity. [source] Sub-lethal heat shock induces plasma membrane translocation of 70-kDa heat shock protein in viable, but not in apoptotic, U-937 leukaemia cellsAPMIS, Issue 3 2010ELENA B. LASUNSKAIA Lasunskaia EB, Fridlianskaia I, Arnholdt AV, Kanashiro M, Guzhova I, Margulis B. Sub-lethal heat shock induces plasma membrane translocation of 70-kDa heat shock protein in viable, but not in apoptotic, U-937 leukaemia cells. APMIS 2010; 118: 179,87. Heat shock protein 70 kDa, Hsp70, is an important intracellular factor that protects cells from stress. Unusual plasma membrane expression of Hsp70, observed in some cancer cells, contributes to the cell's recognition and elimination by the immune system. Induction of apoptosis in cancer cells was demonstrated to increase Hsp70 translocation to the surface membrane, enhancing immunogenic effects through the stimulation of dendritic cells. As hyperthermia is proposed as a method of choice for anti-cancer therapy, we examined whether apoptosis induction by heat shock enhances Hsp70 membrane translocation in U-937 leukaemia cells. Cells were exposed to sub-lethal heat shock, and intracellular and membrane-bound Hsp70 expression was evaluated in apoptotic and viable cell sub-populations, employing flow cytometry and immunofluorescence. Heat shock induced Hsp70 membrane translocation in the viable cells that were able to enhance Hsp70 production upon heating, but not in the cells undergoing apoptosis that continued to express low basal levels of the intracellular protein. Data suggest that the protein translocation was associated with the increasing Hsp70 content rather than the apoptotic process. Apoptosis does not contribute to externalization of Hsp70, at least in the cells with low levels of this protein. [source] Inhibition of heat shock protein 90 sensitizes melanoma cells to thermosensitive ferromagnetic particle-mediated hyperthermia with low Curie temperatureCANCER SCIENCE, Issue 3 2009Aki Ito Heat shock protein (Hsp) 90 is a key regulator of a variety of oncogene products and cell-signaling molecules, and the therapeutic benefit of its inhibition in combination with radiation or chemotherapy has been investigated. In addition, hyperthermia has been used for many years to treat various malignant tumors. We previously described a system in which hyperthermia was induced using thermosensitive ferromagnetic particles (FMP) with a Curie temperature (Tc = 43,C) low enough to mediate automatic temperature control, and demonstrated its antitumor effect in a mouse melanoma model. In the present study, we examined the antitumor effects of combining a Hsp90 inhibitor (geldanamycin; GA) with FMP-mediated hyperthermia. In cultured B16 melanoma cells, GA exerted an antitumor effect by increasing the cells' susceptibility to hyperthermia and reducing expression of Akt. In an in vivo study, melanoma cells were subcutaneously injected into the backs of C57BL/6 mice. FMP were then injected into the resultant tumors, and the mice were divided into four groups: group I, no treatment (control); group II, one hyperthermia treatment; group III, GA alone; and group IV, GA with hyperthermia. When exposed to a magnetic field, the temperature of tissues containing FMP increased and stabilized at the Tc. In group IV, complete regression of tumors was observed in five of nine mice (56%), whereas no tumor regression was seen in groups I,III. Our findings suggest that inhibition of Hsp90 with hyperthermia increases its antitumor effect. Thus, the combination of FMP-mediated, self-regulating hyperthermia with Hsp90 inhibition has important implications for the treatment of cancer. (Cancer Sci 2009; 100: 558,564) [source] Combined in Silico and Experimental Approach for Drug Design: The Binding Mode of Peptidic and Non-Peptidic Inhibitors to Hsp90 N-Terminal DomainCHEMICAL BIOLOGY & DRUG DESIGN, Issue 5 2010Simona Tomaselli Heat shock protein 90 (Hsp90) is a prime target for antitumor therapies. The information obtained by molecular dynamics (MD) simulations is combined with NMR data to provide a cross-validated atomic resolution model of the complementary interactions of heat shock protein 90 with a peptidic (shepherdin) and a non-peptidic (5-aminoimidazole-4-carboxamide-1-,- d -ribofuranoside, AICAR) inhibitor, showing antiproliferative and proapoptotic activity in multiple tumor cell lines. This approach highlights the relevant role of imidazolic moiety in the interaction of both antagonist molecules. In 5-aminoimidazole-4-carboxamide-1-,- d -ribofuranoside bound state, one conformation of those present in solution is selected, where imidazolic, H4 and H5 protons have a key role in defining a non-polar region contacting heat shock protein 90 surface. The dynamic equilibrium between N-type and S-type puckered forms of 5-aminoimidazole-4-carboxamide-1-,- d -ribofuranoside moiety is shown to be functional to inhibitor binding. The first experimental structural data on these inhibitors are presented and discussed as hints for future design of improved molecules. [source] Structural Models and Binding Site Prediction of the C-terminal Domain of Human Hsp90: A New Target for Anticancer DrugsCHEMICAL BIOLOGY & DRUG DESIGN, Issue 5 2008Miriam Sgobba Heat shock protein 90 is a valuable target for anticancer drugs because of its role in the activation and stabilization of multiple oncogenic signalling proteins. While several compounds inhibit heat shock protein 90 by binding the N-terminal domain, recent studies have proved that the C-terminal domain is important for dimerization of the chaperone and contains an additional binding site for inhibitors. Heat shock protein 90 inhibition achieved with molecules binding to the C-terminal domain provides an additional and novel opportunity to design and develop drugs. Therefore, for the first time, we have investigated the structure and the dynamic behaviour of the C-terminal domain of human heat shock protein 90 with and without the small-middle domain, using homology modelling and molecular dynamics simulations. In addition, secondary structure predictions and peptide folding simulations proved useful to investigate a putative additional ,-helix located between H18 and ,20 of the C-terminal domain. Finally, we used the structural information to infer the location of the binding site located in the C-terminal domain by using a number of computational tools. The predicted pocket is formed by two grooves located between helix H18, the loop downstream of H18 and the loop connecting helices H20 and H21 of each monomer of the C-terminal domain, with only two amino acids contributing from each middle domain. [source] Hsp90 as a Target for Drug DevelopmentCHEMMEDCHEM, Issue 12 2006Subhabrata Chaudhury Blocking the chaperones: Heat shock protein,90 (Hsp90) has emerged as a promising target for the treatment of cancer, Alzheimer's and Parkinson's diseases, motor impairments, multiple sclerosis, and other disorders. Progress toward the development of both N- and C-terminal inhibitors is described. [source] Heat Shock Protein Expression is Increased in Cardiac and Skeletal Muscles of Fischer 344 Rats After Endurance TrainingEXPERIMENTAL PHYSIOLOGY, Issue 1 2000T. R. Samelman Heat shock proteins (HSPs) are expressed when cells are exposed to various types of stress and they may provide protection against cellular insult. Previous data have shown increases in HSP expression following acute exhaustive exercise in rats (Locke et al. 1990, 1995; Salo et al. 1991) and humans (Liu et al. 1999); however, it is not known if chronic exercise will increase resting levels of HSPs. The purpose of this study was to determine if basal protein levels of HSP 72/73 and HSP 60 are increased in cardiac and skeletal muscle of endurance trained Fischer 344 rats. Heart, soleus (SOL) and lateral gastrocnemius (LG) muscles were removed and hearts were sectioned into left ventricle (LV), right ventricle (RV) and atria (AT). Endurance training improved myocardial citrate synthase activity by 88, 90 and 77% and cytochrome c oxidase activity by 58, 51 and 89% in LV, RV and AT, respectively. LV and RV oxidative enzyme activities were greater when compared to AT for both trained and untrained rats (P < 0.05). HSP 72/73 expression was significantly greater (P < 0.05) in LV, RV and SOL from endurance trained versus from control rats (26, 45 and 67%, respectively). HSP 60 was also increased (P < 0.05) in LV, RV and SOL in trained relative to untrained rats. HSP 72/73 and HSP 60 were unchanged in AT and LG after training. These results indicate that endurance training increases the basal expression of stress proteins and this observation is consistent with the hypothesis that endurance training may activate a protective mechanism to stress. [source] Impact of heat shock on heat shock proteins expression, biological and commercial traits of Bombyx moriINSECT SCIENCE, Issue 4 2006VASUDHA B. CHAVADI Abstract We report the thermotolerance of new bivoltine silkworm, Bombyx mori strains NB4D2, KSO1, NP2, CSR2 and CSR4and differential expression of heat shock proteins at different instars. Different instars of silkworm larva were subjected to heat shock at 35°C, 40°C and 45°C for 2 hours followed by 2 hours recovery. Heat shock proteins were analyzed by SDS-PAGE. The impact of heat shock on commercial traits of cocoons was analyzed by following different strategies in terms of acquired thermotolerance over control. Comparatively NP2 exhibited better survivability than other strains. Resistance to heat shock was increased as larval development proceeds in the order of first instar > second instar > third instar > fourth instar > fifth instar in all silkworm strains. Expression of heat shock proteins varies in different instars. 90 kDa in the first, second and third instars, 84 kDa in the fourth instar and 84, 62, 60, 47 and 33 kDa heat shock proteins in fifth instar was observed in response to heat shock. Relative influence of heat shock on commercial traits that correspond to different stages was significant in all strains. In NB4D2, cocoon and shell weight significantly increased to 17.52% and 19.44% over control respectively. Heat shock proteins as molecular markers for evaluation and evolution of thermotolerant silkworm strains for tropics was discussed. [source] Heat shock protein 27: its potential role in vascular diseaseINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 4 2006Gordon Ferns Summary Heat shock proteins are molecular chaperones that have an ability to protect proteins from damage induced by environmental factors such as free radicals, heat, ischaemia and toxins, allowing denatured proteins to adopt their native configuration. Heat shock protein-27 (Hsp27) is a member of the small Hsp (sHsp) family of proteins, and has a molecular weight of approximately 27 KDa. In addition to its role as a chaperone, it has also been reported to have many additional functions. These include effects on the apoptotic pathway, cell movement and embryogenesis. In this review, we have focused on its possible role in vascular disease. [source] HSP70 interacts with TRAF2 and differentially regulates TNF, signalling in human colon cancer cellsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 3 2010Shengming Dai Abstract Members of tumour necrosis factor (TNF) family usually trigger both survival and apoptotic signals in various cell types. Heat shock proteins (HSPs) are conserved proteins implicated in protection of cells from stress stimuli. However, the mechanisms of HSPs in TNF,-induced signalling pathway have not been fully elucidated. We report here that HSP70 over-expression in human colon cancer cells can inhibit TNF,-induced NF,B activation but promote TNF,-induced activation of c-Jun N-terminal kinase (JNK) through interaction with TNF receptor (TNFR)-associated factor 2 (TRAF2). We provide evidence that HSP70 over-expression can sequester TRAF2 in detergent-soluble fractions possibly through interacting with TRAF2, leading to reduced recruitment of receptor-interacting protein (RIP1) and I,B, kinase (IKK) signalosome to the TNFR1,TRADD complex and inhibited NF,B activation after TNF, stimuli. In addition, we found that HSP70,TRAF2 interaction can promote TNF,-induced JNK activation. Therefore, our study suggests that HSP70 may differentially regulate TNF,-induced activation of NF,B and JNK through interaction with TRAF2, contributing to the pro-apoptotic roles of HSP70 in TNF,-induced apoptosis of human colon cancer cells. [source] | |||||||||||||||||||||||||||||||||||||