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Sample records for plastid-targeted heat shock

  1. Heat shock proteins and immunotherapy

    Institute of Scientific and Technical Information of China (English)

    XinZHAO; XueMeiXU; GuoxingSONG

    2005-01-01

    Being one of the most abundant intracellular proteins,heat shock proteins(HSPs) have many housekeeping functions which are crucial for the survival of organisms.In addition,some HSPs are new immunoactive molecules which play important roles in both adaptive and innate immunity.They could activate CD8+ and CD4+ lymphocytes,induce innate immune response including natural killer(NK) cell activation and cytokine secretion,and induce maturation of dendritic cells(DCs).These characteristics have been used for immunotherapy of various types of cancers and infectious disenses.This review focuses on the main HSP families——HSP70 and 90 families.The mechanism of HSPs’ function in eliciting immune response are elucidated and various forms of HSPs used in immunotherapy are discussed in details.At the end of this review,authors summarize clinical trials related to HSPs and evaluate their clinical efficacy.

  2. Heat Shock Proteins and Diabetes.

    Science.gov (United States)

    Zilaee, Marzie; Shirali, Saeed

    2016-12-01

    Diabetes is a chronic disease, and its prevalence continues to rise and can increase the risk for the progression of microvascular (such as nephropathy, retinopathy and neuropathy) and also macrovascular complications. Diabetes is a condition in which the oxidative stress and inflammation rise. Heat shock proteins (HSPs) are a highly conserved family of proteins that are expressed by all cells exposed to environmental stress, and they have diverse functions. In patients with diabetes, the expression and levels of HSPs decrease, but these chaperones can aid in improving some complications of diabetes, such as oxidative stress and inflammation. (The suppression of some HSPs is associated with a generalized increase in tissue inflammation.) In this review, we summarize the current understanding of HSPs in diabetes as well as their complications, and we also highlight their potential role as therapeutic targets in diabetes. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

  3. Effects of Heat Shock on Glucocorticoid Receptor

    Institute of Scientific and Technical Information of China (English)

    宋亮年

    1994-01-01

    The changes of glucocorticoid receptor (GR) during the heat shock response have been studied using a human osteosarcoma cell line (HOS-8603) as the model. The expression of the heat shock protein 70 (hsp70) mRNA in HOS-8603 cells has been enhanced markedly after a heat treatment at 43 ℃ for 30 min. A mild thermal pretreatment (42℃ for 1 h) protects the HOS-8603 cells against a subsequent heat challenge (46℃). This induced thermotolerance is reflected by the increase of cell viability of HOS-8603 cells. The GR binding activity in HOS-8603 cells decreased rapidly after the heat treatment at 43℃; only 42. 61% of controls were detected 60 min after the heat treatment. However, there was no significant change in the dissociation constant value (Kd). These results indicate that the heat shock induce not only the heat shock mRNA expression, but also the rapid reduction in GR binding activity, suggesting that there might be a functional relationship between GR action and the heat shock response.

  4. Shock Heated Dust in Young Supernova Remnants

    Science.gov (United States)

    Braun, R.; Strom, R. G.; van der Laan, H.; Greidanus, H.

    Infrared emission in young supernova remnants is interpreted as coming from shock-heated dust. Using models and data from other wavelength regimes, many physical parameters of the remnants can accurately be derived.

  5. Heat shock factor 1 prevents the reduction in thrashing due to heat shock in Caenorhabditis elegans.

    Science.gov (United States)

    Furuhashi, Tsubasa; Sakamoto, Kazuichi

    2015-07-01

    Heat shock factor 1 (HSF-1) is activated by heat stress and induces the expression of heat shock proteins. However, the role of HSF-1 in thermotolerance remains unclear. We previously reported that heat stress reversibly reduces thrashing movement in Caenorhabditis elegans. In this study, we analyzed the function of HSF-1 on thermotolerance by monitoring thrashing movement. hsf-1 RNAi suppressed the restoration of thrashing reduced by heat stress. In contrast, hsf-1 knockdown cancelled prevention of movement reduction in insulin/IGF-1-like growth factor 1 receptor (daf-2) mutant, but didn't suppress thrashing restoration in daf-2 mutant. In addition, hsf-1 RNAi accelerated the reduction of thrashing in heat-shocked wild-type C. elegans. And, daf-16 KO didn't accelerate the reduction of thrashing by heat stress. Taken together, these results suggest that HSF-1 prevents the reduction of thrashing caused by heat shock.

  6. Biophoton emission induced by heat shock.

    Directory of Open Access Journals (Sweden)

    Katsuhiro Kobayashi

    Full Text Available Ultraweak biophoton emission originates from the generation of reactive oxygen species (ROS that are produced in mitochondria as by-products of cellular respiration. In healthy cells, the concentration of ROS is minimized by a system of biological antioxidants. However, heat shock changes the equilibrium between oxidative stress and antioxidant activity, that is, a rapid rise in temperature induces biophoton emission from ROS. Although the rate and intensity of biophoton emission was observed to increase in response to elevated temperatures, pretreatment at lower high temperatures inhibited photon emission at higher temperatures. Biophoton measurements are useful for observing and evaluating heat shock.

  7. Heating Cooling Flows with Weak Shock Waves

    CERN Document Server

    Mathews, W G; Brighenti, F

    2006-01-01

    The discovery of extended, approximately spherical weak shock waves in the hot intercluster gas in Perseus and Virgo has precipitated the notion that these waves may be the primary heating process that explains why so little gas cools to low temperatures. This type of heating has received additional support from recent gasdynamical models. We show here that outward propagating, dissipating waves deposit most of their energy near the center of the cluster atmosphere. Consequently, if the gas is heated by (intermittent) weak shocks for several Gyrs, the gas within 30-50 kpc is heated to temperatures that far exceed observed values. This heating can be avoided if dissipating shocks are sufficiently infrequent or weak so as not to be the primary source of global heating. Local PV and viscous heating associated with newly formed X-ray cavities are likely to be small, which is consistent with the low gas temperatures generally observed near the centers of groups and clusters where the cavities are located.

  8. [Heat shock proteins and their characteristics].

    Science.gov (United States)

    Dzaman-Serafin, Sylwia; Telatyńska-Mieszek, Bogumiła; Ciechanowski, Kazimierz

    2005-08-01

    The main adaptable response to increased temperature is heat shock response resulting in induction of proteins called heat shock proteins (HSP). They are present in all cells under proper growth conditions and they create 5-10% of the whole protein contents. HSP were divided into five basic groups according to their approximate molecular mass, expressed in kDa and called respectively: HSP 100, HSP 90, HSP 70, HSP 60 and small HSP. Heat shock proteins can act like antigens in many infectious diseases. Immunological response against proteins from HSP 60, HSP 70 and HSP 90 families was observed in diseases caused by bacterial and protozoan pathogens. It is known that ischemia and reperfusion activate HSP genes transcription in heart cells of various experimental animals. Human and Chlamydia pneumoniae HSP 60 were found in patients with stable coronary disease. Hence many researchers connect the increase of ischaemia with the passed infection caused by Chlamydia pneumoniae, which can influence the origin or development of atheromatous plaque in the vascular wall. HSPs play an important role in hyperthermic therapy commonly used together with irradiation. Moreover, works on the possibility of HSP application to delay of disease process in neurodegenerative diseases, such as Parkinson or Alzheimer diseases are conducted. The paper presents characteristics of heat shock proteins, role in the state of health and disease and possibilities of their usage in monitoring and/or treatment of diseases, e.g. cancers.

  9. Heat shock and heat shock protein 70i enhance the oncolytic effect of replicative adenovirus.

    Science.gov (United States)

    Haviv, Y S; Blackwell, J L; Li, H; Wang, M; Lei, X; Curiel, D T

    2001-12-01

    Replication-competent viruses are currently being evaluated for their cancer cell-killing properties. These vectors are designed to induce tumor regression after selective viral propagation within the tumor. However, replication-competent viruses have not resulted heretofore in complete tumor eradication in the clinical setting. Recently, heat shock has been reported to partially alleviate replication restriction on an avian adenovirus (Ad) in a human lung cancer cell line. Therefore, we hypothesized that heat shock and overexpression of heat shock protein (hsp) would support the oncolytic effect of a replication-competent human Ad. To this end, we tested the oncolytic and burst kinetics of a replication-competent Ad after exposure to heat shock or to inducible hsp 70 overexpression by a replication-deficient Ad (Adhsp 70i). Heat-shock resulted in augmentation of Ad burst and oncolysis while decreasing total intracellular Ad DNA. Overexpression of hsp 70i also enhanced Ad-mediated oncolysis but did not decrease intracellular Ad DNA levels. We conclude that heat shock and Adhsp 70i enhance the Ad cell-killing potential via distinct mechanisms. A potential therapeutic implication would be the use of local hyperthermia to augment oncolysis by increasing the burst of replication-competent Ad. The role of hsp in Ad-mediated oncolysis should be additionally explored.

  10. Heterogeneous nuclear ribonucleoprotein K inhibits heat shock-induced transcriptional activity of heat shock factor 1.

    Science.gov (United States)

    Kim, Hee-Jung; Lee, Jae-Jin; Cho, Jin-Hwan; Jeong, Jaeho; Park, A Young; Kang, Wonmo; Lee, Kong-Joo

    2017-08-04

    When cells are exposed to heat shock and various other stresses, heat shock factor 1 (HSF1) is activated, and the heat shock response (HSR) is elicited. To better understand the molecular regulation of the HSR, we used 2D-PAGE-based proteome analysis to screen for heat shock-induced post-translationally modified cellular proteins. Our analysis revealed that two protein spots typically present on 2D-PAGE gels and containing heterogeneous nuclear ribonucleoprotein K (hnRNP K) with trioxidized Cys(132) disappeared after the heat shock treatment and reappeared during recovery, but the total amount of hnRNP K protein remained unchanged. We next tested whether hnRNP K plays a role in HSR by regulating HSF1 and found that hnRNP K inhibits HSF1 activity, resulting in reduced expression of hsp70 and hsp27 mRNAs. hnRNP K also reduced binding affinity of HSF1 to the heat shock element by directly interacting with HSF1 but did not affect HSF1 phosphorylation-dependent activation or nuclear localization. hnRNP K lost its ability to induce these effects when its Cys(132) was substituted with Ser, Asp, or Glu. These findings suggest that hnRNP K inhibits transcriptional activity of HSF1 by inhibiting its binding to heat shock element and that the oxidation status of Cys(132) in hnRNP K is critical for this inhibition. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Impact of heat shock on heat shock proteins expression,biological and commercial traits of Bombyx mori

    Institute of Scientific and Technical Information of China (English)

    VASUDHA B. CHAVADI; APARNA H. S OSALEGOWDA; MANJUNATHA H.B OREGOWDA

    2006-01-01

    We report the thermotolerance of new bivoltine silkworm, Bombyx mori strains NB4D2, KSO1, NP2, CSR2 and CSR4 and differential expression of heat shock proteins at different instars. Different instars of silkworm larva were subjected to heat shock at 35℃,40℃ and 45℃ 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.

  12. Barcoding heat shock proteins to human diseases : looking beyond the heat shock response

    NARCIS (Netherlands)

    Kakkar, Vaishali; Meister-Broekema, Melanie; Minoia, Melania; Carra, Serena; Kampinga, Harm H.

    There are numerous human diseases that are associated with protein misfolding and the formation of toxic protein aggregates. Activating the heat shock response (HSR) - and thus generally restoring the disturbed protein homeostasis associated with such diseases - has often been suggested as a

  13. Developmental control of the heat shock response in Xenopus.

    OpenAIRE

    Bienz, M

    1984-01-01

    Xenopus cells express two major proteins on heat shock, designated hsp 70 and hsp 30. Several cDNA clones for the corresponding mRNAs were identified and sequenced. Inducibility and abundance of heat shock mRNAs in various cell types and developmental stages was determined by nuclease S1-mapping. The only cells found to contain hsp 70 mRNA without heat shock are the oocytes. The level of this stored hsp 70 mRNA is not increased by heat shock. After fertilization, hsp 70 mRNA becomes undetecta...

  14. Horizontal transfer of a eukaryotic plastid-targeted protein gene to cyanobacteria

    Directory of Open Access Journals (Sweden)

    Keeling Patrick J

    2007-06-01

    Full Text Available Abstract Background Horizontal or lateral transfer of genetic material between distantly related prokaryotes has been shown to play a major role in the evolution of bacterial and archaeal genomes, but exchange of genes between prokaryotes and eukaryotes is not as well understood. In particular, gene flow from eukaryotes to prokaryotes is rarely documented with strong support, which is unusual since prokaryotic genomes appear to readily accept foreign genes. Results Here, we show that abundant marine cyanobacteria in the related genera Synechococcus and Prochlorococcus acquired a key Calvin cycle/glycolytic enzyme from a eukaryote. Two non-homologous forms of fructose bisphosphate aldolase (FBA are characteristic of eukaryotes and prokaryotes respectively. However, a eukaryotic gene has been inserted immediately upstream of the ancestral prokaryotic gene in several strains (ecotypes of Synechococcus and Prochlorococcus. In one lineage this new gene has replaced the ancestral gene altogether. The eukaryotic gene is most closely related to the plastid-targeted FBA from red algae. This eukaryotic-type FBA once replaced the plastid/cyanobacterial type in photosynthetic eukaryotes, hinting at a possible functional advantage in Calvin cycle reactions. The strains that now possess this eukaryotic FBA are scattered across the tree of Synechococcus and Prochlorococcus, perhaps because the gene has been transferred multiple times among cyanobacteria, or more likely because it has been selectively retained only in certain lineages. Conclusion A gene for plastid-targeted FBA has been transferred from red algae to cyanobacteria, where it has inserted itself beside its non-homologous, functional analogue. Its current distribution in Prochlorococcus and Synechococcus is punctate, suggesting a complex history since its introduction to this group.

  15. A phylogenetic mosaic plastid proteome and unusual plastid-targeting signals in the green-colored dinoflagellate Lepidodinium chlorophorum

    Directory of Open Access Journals (Sweden)

    Inagaki Yuji

    2010-06-01

    Full Text Available Abstract Background Plastid replacements through secondary endosymbioses include massive transfer of genes from the endosymbiont to the host nucleus and require a new targeting system to enable transport of the plastid-targeted proteins across 3-4 plastid membranes. The dinoflagellates are the only eukaryotic lineage that has been shown to have undergone several plastid replacement events, and this group is thus highly relevant for studying the processes involved in plastid evolution. In this study, we analyzed the phylogenetic origin and N-terminal extensions of plastid-targeted proteins from Lepidodinium chlorophorum, a member of the only dinoflagellate genus that harbors a green secondary plastid rather than the red algal-derived, peridinin-containing plastid usually found in photosynthetic dinoflagellates. Results We sequenced 4,746 randomly picked clones from a L. chlorophorum cDNA library. 22 of the assembled genes were identified as genes encoding proteins functioning in plastids. Some of these were of green algal origin. This confirms that genes have been transferred from the plastid to the host nucleus of L. chlorophorum and indicates that the plastid is fully integrated as an organelle in the host. Other nuclear-encoded plastid-targeted protein genes, however, are clearly not of green algal origin, but have been derived from a number of different algal groups, including dinoflagellates, streptophytes, heterokonts, and red algae. The characteristics of N-terminal plastid-targeting peptides of all of these genes are substantially different from those found in peridinin-containing dinoflagellates and green algae. Conclusions L. chlorophorum expresses plastid-targeted proteins with a range of different origins, which probably arose through endosymbiotic gene transfer (EGT and horizontal gene transfer (HGT. The N-terminal extension of the genes is different from the extensions found in green alga and other dinoflagellates (peridinin- and

  16. Differential recognition of heat shock elements by members of the heat shock transcription factor family.

    Science.gov (United States)

    Yamamoto, Noritaka; Takemori, Yukiko; Sakurai, Mayumi; Sugiyama, Kazuhisa; Sakurai, Hiroshi

    2009-04-01

    Heat shock transcription factor (HSF), an evolutionarily conserved stress response regulator, forms trimers and binds to heat shock element (HSE), comprising at least three continuous inverted repeats of the sequence 5'-nGAAn-3'. The single HSF of yeast is also able to bind discontinuously arranged nGAAn units. We investigated interactions between three human HSFs and various HSE types in vitro, in yeast cells, and in HeLa cells. Human HSF1, a stress-activated regulator, preferentially bound to continuous HSEs rather than discontinuous HSEs, and heat shock of HeLa cells caused expression of reporter genes containing continuous HSEs. HSF2, whose function is implicated in neuronal specification and spermatogenesis, exhibited a slightly higher binding affinity to discontinuous HSEs than did HSF1. HSF4, a protein required for ocular lens development, efficiently recognized discontinuous HSEs in a trimerization-dependent manner. Among four human gamma-crystallin genes encoding structural proteins of the lens, heat-induced HSF1 preferred HSEs on the gammaA-crystallin and gammaB-crystallin promoters, whereas HSF4 preferred HSE on the gammaC-crystallin promoter. These results suggest that the HSE architecture is an important determinant of which HSF members regulate genes in diverse cellular processes.

  17. Heat shock proteins: Molecules with assorted functions

    Institute of Scientific and Technical Information of China (English)

    Surajit SARKAR; M. Dhruba SINGH; Renu YADAV; K. P. ARUNKUMAR; Geoffrey W. PITTMAN

    2011-01-01

    Heat shock proteins (Hsps) or molecular chaperones,are highly conserved protein families present in all studied organisms.Following cellular stress,the intracellular concentration of Hsps generally increases several folds.Hsps undergo ATP-driven conformational changes to stabilize unfolded proteins or unfold them for transiocation across membranes or mark them for degradation.They are broadly classified in several families according to their molecular weights and functional properties.Extensive studies during the past few decades suggest that Hsps play a vital role in both normal cellular homeostasis and stress response.Hsps have been reported to interact with numerous substrates and are involved in many biological functions such as cellular communication,immune response,protein transport,apoptosis,cell cycle regulation,gametogenesis and aging.The present review attempts to provide a brief overview of various Hsps and summarizes their involvement in diverse biological activities.

  18. Heat Shock Protein and Innate Immunity

    Institute of Scientific and Technical Information of China (English)

    Min-FuTsan; BaochongGao

    2004-01-01

    In addition to serving as molecular chaperones, heat shock proteins (HSPs) have been implicated in autoimmune diseases, antigen presentation and tumor immunity. Extensive work in the last 10 years has also suggested that HSPs such as Hsp60, Hsp70, Hsp90 and gp96, may be potent activators of the innate immune system capable of inducing the production of pro-inflammatory cytokines by the monocyte-macrophage system, and the activation and maturation of dendritic cells via the Toll-like receptor 2 and 4 signal transduction pathways. However, recent evidence suggests that the reported cytokine effects of HSPs may be a result of the contaminating bacterial cell-wall products. This concise review summarizes the current controversy over the role of HSPs in innate immunity. Cellular & Molecular Immunology.

  19. Heat Shock Protein and Innate Immunity

    Institute of Scientific and Technical Information of China (English)

    Min-Fu Tsan; Baochong Gao

    2004-01-01

    In addition to serving as molecular chaperones, heat shock proteins (HSPs) have been implicated in autoimmune diseases, antigen presentation and tumor immunity. Extensive work in the last 10 years has also suggested that HSPs such as Hsp60, Hsp70, Hsp90 and gp96, may be potent activators of the innate immune system capable of inducing the production of pro-inflammatory cytokines by the monocyte-macrophage system, and the activation and maturation of dendritic cells via the Toll-like receptor 2 and 4 signal transduction pathways. However, recent evidence suggests that the reported cytokine effects of HSPs may be a result of the contaminating bacterial cell-wall products. This concise review summarizes the current controversy over the role of HSPs in innate immunity.

  20. Chromosome Behavior of Heat Shock Induced Triploid in Fenneropenaeus Chinensis

    Institute of Scientific and Technical Information of China (English)

    张晓军; 李富花; 相建海

    2003-01-01

    Triploidy was induced in Chinese shrimp Fenneropenaeus chinensis by 30 + 0.5 ℃ heat shock treatment (initiated at 20 min after fertilization) for 10 min to inhibit the release of PB2 at 18.0℃ . The highest triploid rate obtained was 84.5% in nauplius stage. The effect of heat shock treatment on meiosis and cleavage of eggs was investigated in this work aimed to establish ef ficient procedures for triploid induction and to gain understanding of the mechanism of triploid production. Three pronuclei that could be observed in the treated eggs under fluorescence microscope developed into triploid embryos. Some abnormal chromosome behavior was observed in heat shocked eggs.

  1. Heat shock transcription factors regulate heat induced cell death in a rat histiocytoma

    Indian Academy of Sciences (India)

    Kolla V, P Rasad; Aftab Taiyab; D Jyothi; Usha K Srinivas; Amere S Sreedhar

    2007-04-01

    Heat shock response is associated with the synthesis of heat shock proteins (Hsps) which is strictly regulated by different members of heat shock transcription factors (HSFs). We previously reported that a rat histiocytoma, BC-8 failed to synthesize Hsps when subjected to typical heat shock conditions (42°C, 60 min). The lack of Hsp synthesis in these cells was due to a failure in HSF1 DNA binding activity. In the present study we report that BC-8 tumor cells when subjected to heat shock at higher temperature (43°C, 60 min) or incubation for longer time at 42°C, exhibited necrosis characteristics; however, under mild heat shock (42°C, 30 min) conditions cells showed activation of autophagy. Mild heat shock treatment induced proteolysis of HSF1, and under similar conditions we observed an increase in HSF2 expression followed by its enhanced DNA binding activity. Inhibiting HSF1 proteolysis by reversible proteasome inhibition failed to inhibit heat shock induced autophagy. Compromising HSF2 expression but not HSF1 resulted in the inhibition of autophagy, suggesting HSF2 dependent activation of autophagy. We are reporting for the first time that HSF2 is heat inducible and functions in heat shock induced autophagic cell death in BC-8 tumor cells.

  2. Heat-shock protein 70: molecular supertool?

    Science.gov (United States)

    Aufricht, Christoph

    2005-06-01

    The cellular stress response decreases cellular injury, either via primary induction of cytoresistance or by secondary enhancement of cellular repair mechanisms. The most frequently studied and best understood effectors of the cellular stress response are the heat shock proteins (HSP). HSP are among the oldest tools in the cellular protein machinery, demonstrating extremely high conservation of the genetic code since bacteria. Molecular chaperons, with the HSP-70 being the prototype, cooperate in transport and folding of proteins, preventing aggregation, and even resolubilizing injured proteins. Increasing evidence supports a role for HSP during the recovery from renal ischemia, in particular in cellular salvage from apoptotic cell death and cytoskeletal restoration. Recent studies also report the potential for biomolecular profiling of newborns for the risk of acute renal failure. In peritoneal dialysis novel data suggest the use of HSP expression for biocompatibility testing. More importantly, HSP are prime therapeutic candidates for clinical situations associated with predictable insults, such as organ procurement in transplant medicine and repetitive exposure to hyperosmolar and acidotic peritoneal dialysis fluids. The next challenge will be to define the regulatory pathways of the cellular stress response in these models to introduce novel therapeutic interventions, such as new pharmaceutics enhancing the HSP expression.

  3. Heat shock protein 90: the cancer chaperone

    Indian Academy of Sciences (India)

    Len Neckers

    2007-04-01

    Heat shock protein 90 (Hsp90) is a molecular chaperone required for the stability and function of a number of conditionally activated and/or expressed signalling proteins, as well as multiple mutated, chimeric, and/or over-expressed signalling proteins, that promote cancer cell growth and/or survival. Hsp90 inhibitors are unique in that, although they are directed towards a specific molecular target, they simultaneously inhibit multiple cellular signalling pathways. By inhibiting nodal points in multiple overlapping survival pathways utilized by cancer cells, combination of an Hsp90 inhibitor with standard chemotherapeutic agents may dramatically increase the in vivo efficacy of the standard agent. Hsp90 inhibitors may circumvent the characteristic genetic plasticity that has allowed cancer cells to eventually evade the toxic effects of most molecularly targeted agents. The mechanism-based use of Hsp90 inhibitors, both alone and in combination with other drugs, should be effective toward multiple forms of cancer. Further, because Hsp90 inhibitors also induce Hsf-1-dependent expression of Hsp70, and because certain mutated Hsp90 client proteins are neurotoxic, these drugs display ameliorative properties in several neurodegenerative disease models, suggesting a novel role for Hsp90 inhibitors in treating multiple pathologies involving neurodegeneration.

  4. Heat Shock Proteins, Autoimmunity, and Cancer Treatment

    Directory of Open Access Journals (Sweden)

    Stuart K. Calderwood

    2012-01-01

    Full Text Available Heat shock proteins (HSPs have been linked to the therapy of both cancer and inflammatory diseases, approaches that utilize contrasting immune properties of these proteins. It would appear that HSP family members Hsp60 and Hsp70, whether from external sources or induced locally during inflammation, can be processed by antigen-presenting cells and that HSP-derived epitopes then activate regulatory T cells and suppress inflammatory diseases. These effects also extend to the HSP-rich environments of cancer cells where elevated HSP concentrations may participate in the immunosuppressive tumor milieu. However, HSPs can also be important mediators of tumor immunity. Due to their molecular chaperone properties, some HSPs can bind tumor-specific peptides and deliver them deep into the antigen-processing pathways of antigen-presenting cells (APCs. In this context, HSP-based vaccines can activate tumor-specific immunity, trigger the proliferation and CTL capabilities of cancer-specific CD8+ T cells, and inhibit tumor growth. Further advances in HSP-based anticancer immunotherapy appear to involve improving the properties of the molecular chaperone vaccines by enhancing their antigen-binding properties and combating the immunosuppressive tumor milieu to permit programming of active CTL capable of penetrating the tumor milieu and specifically targeting tumor cells.

  5. Heat-shock proteins in clinical neurology.

    Science.gov (United States)

    Romi, Fredrik; Helgeland, Geir; Gilhus, Nils Erik

    2011-01-01

    Heat-shock proteins (HSPs) are antigen-presenting protein-aggregation-preventing chaperones, induced by cellular stress in eukaryotic cells. In this review, we focus on recent HSP advances in neurological disorders. In myasthenia gravis, patients responding to immunosuppressive therapy have reduced serum HSP-71 antibodies. Generalized and ocular myasthenia gravis patients have elevated serum HSP-70 antibodies, indicating common pathogenic mechanisms. In Guillain-Barré syndrome, HSP-70 antibodies are elevated in serum and cerebrospinal fluid, and serum levels are higher than in myasthenia gravis and multiple sclerosis. In multiple sclerosis, serum HSP-27 antibodies are elevated during relapses providing disease activation marker, while α,β-crystallin expression in brain lesions indicates remission phase initiation. In acute stroke, serum HSP-27 antibodies are elevated irrespective of stroke type and duration. In epilepsy, HSP-27 is induced in patients' astrocytes and cerebral blood vessel walls, and α,β-crystallin is expressed in epileptic foci. In neurodegenerative disorders such as Alzheimer dementia and Parkinson's disease, HSPs are upregulated in brain tissue, and α,β-crystallin modulates superoxide dismutase-1 (SOD-1) tissue accumulation in familial amyotrophic lateral sclerosis. HSPs play an important role in antigen-presentation and tolerance development. Antibody-mediated interference with their function alters immune responses causing neuropathology. The role of HSPs in clinical neurology should be the subject of future investigation.

  6. Heat shock response and autophagy--cooperation and control.

    Science.gov (United States)

    Dokladny, Karol; Myers, Orrin B; Moseley, Pope L

    2015-01-01

    Protein quality control (proteostasis) depends on constant protein degradation and resynthesis, and is essential for proper homeostasis in systems from single cells to whole organisms. Cells possess several mechanisms and processes to maintain proteostasis. At one end of the spectrum, the heat shock proteins modulate protein folding and repair. At the other end, the proteasome and autophagy as well as other lysosome-dependent systems, function in the degradation of dysfunctional proteins. In this review, we examine how these systems interact to maintain proteostasis. Both the direct cellular data on heat shock control over autophagy and the time course of exercise-associated changes in humans support the model that heat shock response and autophagy are tightly linked. Studying the links between exercise stress and molecular control of proteostasis provides evidence that the heat shock response and autophagy coordinate and undergo sequential activation and downregulation, and that this is essential for proper proteostasis in eukaryotic systems.

  7. Analysis of essential Arabidopsis nuclear genes encoding plastid-targeted proteins.

    Directory of Open Access Journals (Sweden)

    Linda J Savage

    Full Text Available The Chloroplast 2010 Project (http://www.plastid.msu.edu/ identified and phenotypically characterized homozygous mutants in over three thousand genes, the majority of which encode plastid-targeted proteins. Despite extensive screening by the community, no homozygous mutant alleles were available for several hundred genes, suggesting that these might be enriched for genes of essential function. Attempts were made to generate homozygotes in ~1200 of these lines and 521 of the homozygous viable lines obtained were deposited in the Arabidopsis Biological Resource Center (http://abrc.osu.edu/. Lines that did not yield a homozygote in soil were tested as potentially homozygous lethal due to defects either in seed or seedling development. Mutants were characterized at four stages of development: developing seed, mature seed, at germination, and developing seedlings. To distinguish seed development or seed pigment-defective mutants from seedling development mutants, development of seeds was assayed in siliques from heterozygous plants. Segregating seeds from heterozygous parents were sown on supplemented media in an attempt to rescue homozygous seedlings that could not germinate or survive in soil. Growth of segregating seeds in air and air enriched to 0.3% carbon dioxide was compared to discover mutants potentially impaired in photorespiration or otherwise responsive to CO2 supplementation. Chlorophyll fluorescence measurements identified CO2-responsive mutants with altered photosynthetic parameters. Examples of genes with a viable mutant allele and one or more putative homozygous-lethal alleles were documented. RT-PCR of homozygotes for potentially weak alleles revealed that essential genes may remain undiscovered because of the lack of a true null mutant allele. This work revealed 33 genes with two or more lethal alleles and 73 genes whose essentiality was not confirmed with an independent lethal mutation, although in some cases second leaky alleles

  8. Modification of tooth development by heat shock protein 60

    OpenAIRE

    Papp Tamás; Polyák Angéla; Papp Krisztina; Mészár Zoltán (1977-) (állatorvos); Zákány Róza (1963-) (anatómus-, kötőszövetbiológus); Mészár-Katona Éva (1986-) (Ph.D hallgató); Terdik Tünde (1969-) (analitikus); Chang, Hwa Ham; Felszeghy Szabolcs Béla (1972-) (fogorvos, anatómus, kötőszövetbiológus)

    2016-01-01

    Although several heat shock proteins have been investigated in relation to tooth development, no available information is available about the spatial and temporal expression pattern of heat shock protein 60 (Hsp 60). To characterize Hsp 60 expression in the structures of the developing tooth germ, we used Western blotting, immunohistochemistry and in situ hybridization. Hsp 60 was present in high amounts in the inner and outer enamel epithelia, enamel knot (EK) and stratum intermedium (SI). H...

  9. Thermotolerance and Human Performance: Role of Heat Shock Proteins

    Science.gov (United States)

    2009-10-01

    of the significant teratogens in humans, animals, and insects. However, protection from teratogenic effects as is true for various aspects of the...heat shock proteins as molecular chaperones. Annu Rev Cell Biol. 1993;9:601–634 Germain M, Webster W, Edwards M. Hyperthermia as a teratogen ...physical or chemical teratogens are expressed later as enhanced induction of heat shock proteins when embryonic hearts are cultured in

  10. Heat shock response improves heterologous protein secretion in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Hou, Jin; Österlund, Tobias; Liu, Zihe

    2013-01-01

    The yeast Saccharomyces cerevisiae is a widely used platform for the production of heterologous proteins of medical or industrial interest. However, heterologous protein productivity is often low due to limitations of the host strain. Heat shock response (HSR) is an inducible, global, cellular...... stress response, which facilitates the cell recovery from many forms of stress, e.g., heat stress. In S. cerevisiae, HSR is regulated mainly by the transcription factor heat shock factor (Hsf1p) and many of its targets are genes coding for molecular chaperones that promote protein folding and prevent...... the accumulation of mis-folded or aggregated proteins. In this work, we over-expressed a mutant HSF1 gene HSF1-R206S which can constitutively activate HSR, so the heat shock response was induced at different levels, and we studied the impact of HSR on heterologous protein secretion. We found that moderate and high...

  11. Distribution of Mayaro virus RNA in polysomes during heat shock.

    Science.gov (United States)

    Rosas, S L; Herculano, S; Carvalho, M da G

    1997-05-01

    Mayaro virus (alphavirus) infection of Aedes albopictus cells results in inhibition of cell protein synthesis and viral proteins are preferably synthesized. When infected cells are heat shocked, however, there is also an inhibition of viral protein synthesis, and there is preferential synthesis of heat shock proteins. Based on these observations, the distribution of Mayaro viral RNA in polysomes and the association of p34 (capsid protein) with ribosomal fractions of the cells under such conditions have been analyzed. During infection, the viral RNA is mainly observed in light polysomes (60% of total viral RNA in the cell) and also in heavy polysomes (13%). However, when infected cells are heat-shocked, the viral RNA is strongly mobilized from heavy polysomes to the light polysomes fraction and an enrichment in the unbound fraction can be noticed. The amount of p34 associated with the ribosomal fraction was also shown to be decreased in the heat shocked cells. These data lead to the suggestion that two mechanisms could be involved in the inhibition of Mayaro virus protein synthesis in response to heat shock: (1) mobilization of Mayaro virus RNA from heavy to light polysomes; (2) a decrease in the amount of the p34 within the ribosomal fraction.

  12. Mechanical analysis of a heat-shock induced developmental defect

    Science.gov (United States)

    Crews, Sarah M.; McCleery, W. Tyler; Hutson, M. Shane

    2014-03-01

    Embryonic development in Drosophila is a complex process involving coordinated movements of mechanically interacting tissues. Perturbing this system with a transient heat shock can result in a number of developmental defects. In particular, a heat shock applied during the earliest morphogenetic movements of gastrulation can lead to apparent recovery, but then subsequent morphogenetic failure 5-6 hours later during germ band retraction. The process of germ band retraction requires an intact amnioserosa - a single layered extra-embryonic epithelial tissue - and heat shock at gastrulation can induce the later opening of holes in the amnioserosa. These holes are highly correlated with failures of germ band retraction. These holes could be caused by a combination of mechanical weakness in the amnioserosa or local increases in mechanical stress. Here, we assess the role of mechanical stress using confocal imaging to compare cell and tissue morphology in the amnioserosa of normal and heat-shocked embryos and laser hole drilling to map the stress field around the times and locations at which heat-shock induced holes open.

  13. Atypical Particle Heating at a Supercritical Interplanetary Shock

    Science.gov (United States)

    Wilson, Lynn B., III

    2010-01-01

    We present the first observations at an interplanetary shock of large amplitude (> 100 mV/m pk-pk) solitary waves and large amplitude (approx.30 mV/m pk-pk) waves exhibiting characteristics consistent with electron Bernstein waves. The Bernstein-like waves show enhanced power at integer and half-integer harmonics of the cyclotron frequency with a broadened power spectrum at higher frequencies, consistent with the electron cyclotron drift instability. The Bernstein-like waves are obliquely polarized with respect to the magnetic field but parallel to the shock normal direction. Strong particle heating is observed in both the electrons and ions. The observed heating and waveforms are likely due to instabilities driven by the free energy provided by reflected ions at this supercritical interplanetary shock. These results offer new insights into collisionless shock dissipation and wave-particle interactions in the solar wind.

  14. AGN Heating Through Cavities and Shocks

    NARCIS (Netherlands)

    P.E.J. Nulsen; C. Jones; W.R. Forman; L.P. David; B.R. McNamara; D.A. Rafferty; L. Bîrzan; M. Wise

    2007-01-01

    Three comments are made on AGN heating of cooling flows. A simple physical argument is used to show that the enthalpy of a buoyant radio lobe is converted to heat in its wake. Thus, a significant part of ``cavity'' enthalpy is likely to end up as heat. Second, the properties of the repeated weak sho

  15. Heat Shock Proteins in Tendinopathy: Novel Molecular Regulators

    Science.gov (United States)

    Millar, Neal L.; Murrell, George A. C.

    2012-01-01

    Tendon disorders—tendinopathies—are the primary reason for musculoskeletal consultation in primary care and account for up to 30% of rheumatological consultations. Whilst the molecular pathophysiology of tendinopathy remains difficult to interpret the disease process involving repetitive stress, and cellular load provides important mechanistic insight into the area of heat shock proteins which spans many disease processes in the autoimmune community. Heat shock proteins, also called damage-associated molecular patterns (DAMPs), are rapidly released following nonprogrammed cell death, are key effectors of the innate immune system, and critically restore homeostasis by promoting the reconstruction of the effected tissue. Our investigations have highlighted a key role for HSPs in tendion disease which may ultimately affect tissue rescue mechanisms in tendon pathology. This paper aims to provide an overview of the biology of heat shock proteins in soft tissue and how these mediators may be important regulators of inflammatory mediators and matrix regulation in tendinopathy. PMID:23258952

  16. AGN feedback in clusters: shock and sound heating

    CERN Document Server

    Nulsen, P E J

    2013-01-01

    Observations support the view that feedback, in the form of radio outbursts from active nuclei in central galaxies, prevents catastrophic cooling of gas and rapid star formation in many groups and clusters of galaxies. Variations in jet power drive a succession of weak shocks that can heat regions close to the active galactic nuclei (AGN). On larger scales, shocks fade into sound waves. The Braginskii viscosity determines a well-defined sound damping rate in the weakly magnetized intracluster medium (ICM) that can provide sufficient heating on larger scales. It is argued that weak shocks and sound dissipation are the main means by which radio AGN heat the ICM, in which case, the power spectrum of AGN outbursts plays a central role in AGN feedback.

  17. Circuit architecture explains functional similarity of bacterial heat shock responses

    CERN Document Server

    Inoue, Masayo; Trusina, Ala

    2012-01-01

    Heat shock response is a stress response to temperature changes and a consecutive increase in amounts of unfolded proteins. To restore homeostasis, cells upregulate chaperones facilitating protein folding by means of transcription factors (TF). We here investigate two heat shock systems: one characteristic to gram negative bacteria, mediated by transcriptional activator sigma32 in E. coli, and another characteristic to gram positive bacteria, mediated by transcriptional repressor HrcA in L. lactis. We construct simple mathematical model of the two systems focusing on the negative feedbacks, where free chaperons suppress sigma32 activation in the former, while they activate HrcA repression in the latter. We demonstrate that both systems, in spite of the difference at the TF regulation level, are capable of showing very similar heat shock dynamics. We find that differences in regulation impose distinct constrains on chaperone-TF binding affinities: the binding constant of free sigma32 to chaperon DnaK, known to...

  18. Heat Shock Proteins in Tendinopathy: Novel Molecular Regulators

    Directory of Open Access Journals (Sweden)

    Neal L. Millar

    2012-01-01

    Full Text Available Tendon disorders—tendinopathies—are the primary reason for musculoskeletal consultation in primary care and account for up to 30% of rheumatological consultations. Whilst the molecular pathophysiology of tendinopathy remains difficult to interpret the disease process involving repetitive stress, and cellular load provides important mechanistic insight into the area of heat shock proteins which spans many disease processes in the autoimmune community. Heat shock proteins, also called damage-associated molecular patterns (DAMPs, are rapidly released following nonprogrammed cell death, are key effectors of the innate immune system, and critically restore homeostasis by promoting the reconstruction of the effected tissue. Our investigations have highlighted a key role for HSPs in tendion disease which may ultimately affect tissue rescue mechanisms in tendon pathology. This paper aims to provide an overview of the biology of heat shock proteins in soft tissue and how these mediators may be important regulators of inflammatory mediators and matrix regulation in tendinopathy.

  19. ACUPUNCTURE-MOXIBUSTION, HEAT SHOCK PROTEIN 70 AND CYTOPROTECTION

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Heat shock protein 70 (HSP70) is a kind of non-specific cytoprotective protein, and its generation can be induced by acupuncture and moxibustion. In the present paper, the authors review the protective actions of HSP70 on the heart, gastric mucosa, liver, brain tissues, kidney, etc., and the relationship among acupuncture/moxibustion, heat shock protein and the cytoprotective actions. It is worth studying the cytoprotective effect of acupuncture and moxibustion by way of the resultant generation of HSP70 in the organism.

  20. Heat shock factors: integrators of cell stress, development and lifespan.

    Science.gov (United States)

    Akerfelt, Malin; Morimoto, Richard I; Sistonen, Lea

    2010-08-01

    Heat shock factors (HSFs) are essential for all organisms to survive exposures to acute stress. They are best known as inducible transcriptional regulators of genes encoding molecular chaperones and other stress proteins. Four members of the HSF family are also important for normal development and lifespan-enhancing pathways, and the repertoire of HSF targets has thus expanded well beyond the heat shock genes. These unexpected observations have uncovered complex layers of post-translational regulation of HSFs that integrate the metabolic state of the cell with stress biology, and in doing so control fundamental aspects of the health of the proteome and ageing.

  1. Variation of the ratio of specific heats across a detached bow shock

    Science.gov (United States)

    Chao, J. K.; Wiskerchen, M. J.

    1974-01-01

    Equations are derived which allow the ratio of specific heats behind the earth's bow shock to be evaluated if several pre-shock parameters (the specific-heat ratio, the Alfvenic Mach number, the sonic Mach number, and the angle between the shock normal at the stagnation point and the magnetic field) and the density jump across the shock are known. Numerical examples show that the dependence of the post-shock ratio on the pre-shock ratio is weak.

  2. Heat Shock Protein (HSP) Drug Discovery and Development: Targeting Heat Shock Proteins in Disease

    Science.gov (United States)

    Shrestha, Liza; Bolaender, Alexander; Patel, Hardik J.; Taldone, Tony

    2016-01-01

    Heat shock proteins (HSPs) present as a double edged sword. While they play an important role in maintaining protein homeostasis in a normal cell, cancer cells have evolved to co-opt HSP function to promote their own survival. As a result, HSPs such as HSP90 have attracted a great deal of interest as a potential anticancer target. These efforts have resulted in over 20 distinct compounds entering clinical evaluation for the treatment of cancer. However, despite the potent anticancer activity demonstrated in preclinical models, to date no HSP90 inhibitor has obtained regulatory approval. In this review we discuss the unique challenges faced in targeting HSPs that have likely contributed to their lack of progress in the clinic and suggest ways to overcome these so that the enormous potential of these compounds to benefit patients can finally be realized. We also provide a guideline for the future development of HSP-targeted agents based on the many lessons learned during the last two decades in developing HSP90 inhibitors. PMID:27072696

  3. Phylogeny of nuclear-encoded plastid-targeted GAPDH gene supports separate origins for the peridinin- and the fucoxanthin derivative-containing plastids of dinoflagellates.

    Science.gov (United States)

    Takishita, Kiyotaka; Ishida, Ken-Ichiro; Maruyama, Tadashi

    2004-12-01

    Although most photosynthetic dinoflagellates have plastids with peridinin, the three dinoflagellate genera Karenia, Karlodinium, and Takayama possess anomalously pigmented plastids that contain fucoxanthin and its derivatives (19'-hexanoyloxy-fucoxanthin and 19'-butanoyloxy-fucoxanthin) instead of the peridinin. This pigment composition is similar to that of haptophytes. All peridinin-containing dinoflagellates investigated so far have at least two types of glyceraldehyde-3-phosphate dehydrogenase (GAPDH): cytosolic and plastid-targeted forms. In the present study, we cloned and sequenced genes encoding cytosolic and plastid-targeted GAPDH proteins from three species of the fucoxanthin derivative-containing dinoflagellates. Based on the molecular phylogeny, the plastid-targeted GAPDH genes of the fucoxanthin derivative-containing dinoflagellates were closely related to those of haptophyte algae rather than to the peridinin-containing dinoflagellates, while one of several cytosolic versions from the peridinin- and the fucoxanthin derivative-containing dinoflagellates are closely related to each other. Considering a previously reported theory that the plastid-targeted GAPDH from the peridinin-containing dinoflagellates originated by a gene duplication of the cytosolic form before the splitting of the dinoflagellate lineage, it is highly likely that the plastid-targeted GAPDH gene of the peridinin-containing dinoflagellates is original in this algal group and that in the fucoxanthin-containing dinoflagellates, the original plastid-targeted GAPDH was replaced by that of a haptophyte endosymbiont during a tertiary endosymbiosis. The present results strongly support the hypothesis that the plastids of the peridinin- and the fucoxanthin derivative-containing dinoflagellates are of separate origin.

  4. The small heat shock proteins family : The long forgotten chaperones

    NARCIS (Netherlands)

    Garrido, C.; Paul, C.; Seigneuric, R.; Kampinga, H. H.

    2012-01-01

    Small heat shock proteins are a rather heterogeneous family of ATP-independent chaperones, some of which have been proven to block protein aggregation and help the cells to survive stressful conditions. Although much less studied than high molecular weight HSPs like HSP70/HSPA or HSP90/HSPC, their i

  5. Guidelines for the nomenclature of the human heat shock proteins

    NARCIS (Netherlands)

    Kampinga, Harm H.; Hageman, Jurre; Vos, Michel J.; Kubota, Hiroshi; Tanguay, Robert M.; Bruford, Elspeth A.; Cheetham, Michael E.; Chen, B.; Hightower, Lawrence E.

    The expanding number of members in the various human heat shock protein (HSP) families and the inconsistencies in their nomenclature have often led to confusion. Here, we propose new guidelines for the nomenclature of the human HSP families, HSPH (HSP110), HSPC (HSP90), HSPA (HSP70), DNAJ (HSP40),

  6. Small heat shock proteins, protein degradation and protein aggregation diseases

    NARCIS (Netherlands)

    Vos, Michel J.; Zijlstra, Marianne P.; Carra, Serena; Sibon, Ody C. M.; Kampinga, Harm H.

    Small heat shock proteins have been characterized in vitro as ATP-independent molecular chaperones that can prevent aggregation of un- or misfolded proteins and assist in their refolding with the help of ATP-dependent chaperone machines (e. g., the Hsp70 proteins). Comparison of the functionality of

  7. The small heat shock proteins family : The long forgotten chaperones

    NARCIS (Netherlands)

    Garrido, C.; Paul, C.; Seigneuric, R.; Kampinga, H. H.

    2012-01-01

    Small heat shock proteins are a rather heterogeneous family of ATP-independent chaperones, some of which have been proven to block protein aggregation and help the cells to survive stressful conditions. Although much less studied than high molecular weight HSPs like HSP70/HSPA or HSP90/HSPC, their

  8. Guidelines for the nomenclature of the human heat shock proteins

    NARCIS (Netherlands)

    Kampinga, Harm H.; Hageman, Jurre; Vos, Michel J.; Kubota, Hiroshi; Tanguay, Robert M.; Bruford, Elspeth A.; Cheetham, Michael E.; Chen, B.; Hightower, Lawrence E.

    2009-01-01

    The expanding number of members in the various human heat shock protein (HSP) families and the inconsistencies in their nomenclature have often led to confusion. Here, we propose new guidelines for the nomenclature of the human HSP families, HSPH (HSP110), HSPC (HSP90), HSPA (HSP70), DNAJ (HSP40), a

  9. Shock Structure and Shock Heating in the Galactic Central Molecular Zone

    CERN Document Server

    Ott, Juergen; Jones, Paul; Meier, David S

    2014-01-01

    We present maps of a large number of dense molecular gas tracers across the Central Molecular Zone of our Galaxy. The data were taken with the CSIRO/CASS Mopra telescope in Large Projects in the 1.3cm, 7mm, and 3mm wavelength regimes. Here, we focus on the brightness of the shock tracers SiO and HNCO, molecules that are liberated from dust grains under strong (SiO) and weak (HNCO) shocks. The shocks may have occurred when the gas enters the bar regions and the shock differences could be due to differences in the moving cloud mass. Based on tracers of ionizing photons, it is unlikely that the morphological differences are due to selective photo-dissociation of the molecules. We also observe direct heating of molecular gas in strongly shocked zones, with a high SiO/HNCO ratios, where temperatures are determined from the transitions of ammonia. Strong shocks appear to be the most efficient heating source of molecular gas, apart from high energy emission emitted by the central supermassive black hole Sgr A* and t...

  10. A SIMPLE EXPERIMENTAL MODEL OF HEAT SHOCK RESPONSE IN RATS

    Directory of Open Access Journals (Sweden)

    Tufi Neder Meyer

    1998-10-01

    Full Text Available Objective: To obtain a simple model for the elicitation of the heat shock response in rats. Design: Laboratory study. Setting: University research laboratories. Sample: Seventy-nine adult male albino rats (weight range 200 g to 570 g. Procedures: Exposure to heat stress by heating animals in a warm bath for 5 min after their rectal temperatures reached 107.60 F (420 C. Liver and lung samples were collected for heat-shock protein 70 (HSP70 detection (Western analysis. Results: Western analysis was positive for HSP70 in the liver and in the lungs of heated animals. There was a temporal correlation between heating and HSP70 detection: it was strongest 1 day after heating and reduced afterwards. No heated animals died. Conclusion: These data show that heating rats in a warm (45o C bath, according to parameters set in this model, elicits efficiently the heat shock response.OBJETIVO: Obter um modelo simples para tentar esclarecer a resposta ao choque térmico em ratos. LOCAL: Laboratório de pesquisa da Universidade. MÉTODO: Amostra: 79 ratos albinos, adultos, entre 200g a 570g. Procedimentos: Exposição ao calor, em banho quente, por 5 minutos, após a temperatura retal chegar a 42 graus centigrados. Biópsias de fígado e pulmão foram obtidas para detectar a proteina 70 (HSP 70, pelo "Western blot". RESULTADOS: As análises foram positivas nos animais aquecidos, com uma correlação entre aquecimento e constatação da HSP 70. Foi mais elevada no primeiro dia e não houve óbitos nos animais aquecidos. CONCLUSÃO: Os ratos aquecidos a 45 graus centígrados respondem eficientemente ao choque térmico.

  11. Heat shock response and mammal adaptation to high elevation (hypoxia)

    Institute of Scientific and Technical Information of China (English)

    WANG Xiaolin; XU Cunshuan; WANG Xiujie; WANG Dongjie; WANG Qingshang; ZHANG Baochen

    2006-01-01

    The mammal's high elevation (hypoxia) adaptation was studied by using the immunological and the molecular biological methods to understand the significance of Hsp (hypoxia) adaptation in the organic high elevation, through the mammal heat shock response. (1) From high elevation to low elevation (natural hypoxia): Western blot and conventional RT-PCR and real-time fluorescence quota PCR were adopted. Expression difference of heat shock protein of 70 (Hsp70) and natural expression of brain tissue of Hsp70 gene was determined in the cardiac muscle tissue among the different elevation mammals (yak). (2)From low elevation to high elevation (hypoxia induction):The mammals (domestic rabbits) from the low elevation were sent directly to the areas with different high elevations like 2300, 3300 and 5000 m above sea level to be raised for a period of 3 weeks before being slaughtered and the genetic inductive expression of the brain tissue of Hsp70 was determined with RT-PCR. The result indicated that all of the mammals at different elevations possessed their heat shock response gene. Hsp70 of the high elevation mammal rose abruptly under stress and might be induced to come into being by high elevation (hypoxia). The speedy synthesis of Hsp70 in the process of heat shock response is suitable to maintain the cells' normal physiological functions under stress. The Hsp70 has its threshold value. The altitude of 5000 m above sea level is the best condition for the heat shock response, and it starts to reduce when the altitude is over 6000 m above sea level. The Hsp70 production quantity and the cell hypoxia bearing capacity have their direct ratio.

  12. Expression of the heat shock gene clpL of Streptococcus thermophilus is induced by both heat and cold shock

    Directory of Open Access Journals (Sweden)

    Naclerio Gino

    2006-02-01

    Full Text Available Abstract Background Heat and cold shock response are normally considered as independent phenomena. A small amount of evidence suggests instead that interactions may exist between them in two Lactococcus strains. Results We show the occurrence of molecular relationships between the mechanisms of cold and heat adaptations in Streptococcus thermophilus, a lactic acid bacterium widely used in dairy fermentation, where it undergoes both types of stress. We observed that cryotolerance is increased when cells are pre-incubated at high temperature. In addition, the production of a protein, identified as ClpL, a member of the heat-shock ATPase family Clp A/B, is induced at both high and low temperature. A knock-out clpL mutant is deficient in both heat and cold tolerance. However lack of production of this protein does not abolish the positive effect of heat pre-treatment towards cryotolerance. Conclusion Dual induction of ClpL by cold and heat exposure of cells and reduced tolerance to both temperature shocks in a clpL mutant indicates that the two stress responses are correlated in S. thermophilus. However this protein is not responsible by itself for cryotolerance of cells pre-treated at high temperature, indicating that ClpL is necessary for the two phenomena, but does not account by itself for the relationships between them.

  13. SHOCK HEATING OF THE MERGING GALAXY CLUSTER A521

    Energy Technology Data Exchange (ETDEWEB)

    Bourdin, H.; Mazzotta, P. [Dipartimento di Fisica, Universita degli Studi di Roma ' Tor Vergata' , via della Ricerca Scientifica, 1, I-00133 Roma (Italy); Markevitch, M. [NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States); Giacintucci, S. [Joint Space-Science Institute, University of Maryland, College Park, MD 20742-2421 (United States); Brunetti, G., E-mail: herve.bourdin@roma2.infn.it [INAF-Istituto di Radioastronomia, via Gobetti 101, I-40129 Bologna (Italy)

    2013-02-10

    A521 is an interacting galaxy cluster located at z = 0.247, hosting a low-frequency radio halo connected to an eastern radio relic. Previous Chandra observations hinted at the presence of an X-ray brightness edge at the position of the relic, which may be a shock front. We analyze a deep observation of A521 recently performed with XMM-Newton in order to probe the cluster structure up to the outermost regions covered by the radio emission. The cluster atmosphere exhibits various brightness and temperature anisotropies. In particular, two cluster cores appear to be separated by two cold fronts. We find two shock fronts, one that was suggested by Chandra and that is propagating to the east, and another to the southwestern cluster outskirt. The two main interacting clusters appear to be separated by a shock-heated region, which exhibits a spatial correlation with the radio halo. The outer edge of the radio relic coincides spatially with a shock front, suggesting that this shock is responsible for the generation of cosmic-ray electrons in the relic. The propagation direction and Mach number of the shock front derived from the gas density jump, M = 2.4 {+-} 0.2, are consistent with expectations from the radio spectral index, under the assumption of Fermi I acceleration mechanism.

  14. Shock Heating of the Merging Galaxy Cluster A521

    Science.gov (United States)

    Bourdin, H.; Mazzotta, P.; Markevitch, M.; Giacintucci, S.; Brunetti, G.

    2013-01-01

    A521 is an interacting galaxy cluster located at z = 0.247, hosting a low-frequency radio halo connected to an eastern radio relic. Previous Chandra observations hinted at the presence of an X-ray brightness edge at the position of the relic, which may be a shock front. We analyze a deep observation of A521 recently performed with XMM-Newton in order to probe the cluster structure up to the outermost regions covered by the radio emission. The cluster atmosphere exhibits various brightness and temperature anisotropies. In particular, two cluster cores appear to be separated by two cold fronts. We find two shock fronts, one that was suggested by Chandra and that is propagating to the east, and another to the southwestern cluster outskirt. The two main interacting clusters appear to be separated by a shock-heated region, which exhibits a spatial correlation with the radio halo. The outer edge of the radio relic coincides spatially with a shock front, suggesting that this shock is responsible for the generation of cosmic-ray electrons in the relic. The propagation direction and Mach number of the shock front derived from the gas density jump, M = 2.4 +/- 0.2, are consistent with expectations from the radio spectral index, under the assumption of Fermi I acceleration mechanism.

  15. Overexpression of colligin 2 in glioma vasculatureis associated with overexpression of heat shock factor 2

    NARCIS (Netherlands)

    D.A.M. Mustafa (Dana); A.M. Sieuwerts (Anieta); P.P. Zheng (Pingpin); J.M. Kros (Johan)

    2010-01-01

    textabstractIn previous studies we found expression of the protein collig in 2 (heat shock protein 47 (HSP47), SERPINH1) in glioma neovasculature while not in normal brain tissue. Generally, the regulation of heat shock gene expression in eukaryotes is mediated by heat shock factors (HSF). In mammal

  16. Role of heat shock protein 70 in innate alloimmunity

    Directory of Open Access Journals (Sweden)

    Walter G. eLand

    2012-01-01

    Full Text Available This article briefly describes our own experience with the proven demonstration of heat shock protein 70 in reperfused renal allografts from brain-deaddonors and reflects about its potential role as a typical damage-associated molecular pattern (DAMP in the setting of innate alloimmunity. In fact, our group was able to demonstrate a dramatic up-regulation of heat shock protein 70 expression after postischemic reperfusion of renal allografts. Of note, up-regulation of this stress protein expression, although to a lesser extent, was already observed after cold storage of the organ indicating that this molecule is already induced in the stressed organism of a brain-dead donor. However, whether or not the dramatic up-regulation of heat shock protein 70 expression contributes to mounting an innate alloimmune response cannot be judged in view of these clinical findings.Nevertheless, heat shock protein 70, since generated in association with postischemic reperfusion-induced allograft injury, can be called a typical DAMP - as can everymolecule be termed a DAMP that is generated in associationwith any stressful tissue injury regardless of its final positive or negative regulatory function within the innate immune response elicited by it.In fact, as we discuss in this article, the context-dependent, even contradistinctive activities of heat shock protein 70 reflect the biological phenomenon that, throughout evolution, mammals have developed an elaborate network of positive and negative regulatory mechanisms, which provide balance between defensive and protective measures against unwarranted destruction of the host. In this sense, up-regulated expression of heat shock protein 70 in an injured allograft might reflect a pure protective response against the severe oxidative injury of a reperfused donor organ. On the other hand, up-regulated expression of this stress protein in an injured allograft might reflect a(futile attempt of the innate immune system to

  17. Multiple mild heat-shocks decrease the Gompertz component of mortality in Caenorhabditis elegans.

    Science.gov (United States)

    Wu, Deqing; Cypser, James R; Yashin, Anatoli I; Johnson, Thomas E

    2009-09-01

    Exposure to mild heat-stress (heat-shock) can significantly increase the life expectancy of the nematode Caenorhabditis elegans. A single heat-shock early in life extends longevity by 20% or more and affects life-long mortality by decreasing initial mortality only; the rate of increase in subsequent mortality (Gompertz component) is unchanged. Repeated mild heat-shocks throughout life have a larger effect on life span than does a single heat-shock early in life. Here, we ask how multiple heat-shocks affect the mortality trajectory in nematodes and find increases of life expectancy of close to 50% and of maximum longevity as well. We examined mortality using large numbers of animals and found that multiple heat-shocks not only decrease initial mortality, but also slow the Gompertz rate of increase in mortality. Thus, multiple heat-shocks have anti-aging hormetic effects and represent an effective approach for modulating aging.

  18. Shock heating of the merging galaxy cluster A521

    CERN Document Server

    Bourdin, H; Markevitch, M; Giacintucci,; Brunetti, G; 10.1088/0004-637X/764/1/82

    2013-01-01

    A521 is an interacting galaxy cluster located at z=0.247, hosting a low frequency radio halo connected to an eastern radio relic. Previous Chandra observations hinted at the presence of an X-ray brightness edge at the position of the relic, which may be a shock front. We analyze a deep observation of A521 recently performed with XMM-Newton in order to probe the cluster structure up to the outermost regions covered by the radio emission. The cluster atmosphere exhibits various brightness and temperature anisotropies. In particular, two cluster cores appear to be separated by two cold fronts. We find two shock fronts, one that was suggested by Chandra and that is propagating to the east, and another to the southwestern cluster outskirt. The two main interacting clusters appear to be separated by a shock heated region, which exhibits a spatial correlation with the radio halo. The outer edge of the radio relic coincides spatially with a shock front, suggesting this shock is responsible for the generation of cosmi...

  19. Implication of Heat Shock Factors in Tumorigenesis: Therapeutical Potential

    Energy Technology Data Exchange (ETDEWEB)

    Thonel, Aurelie de [INSERM U866, Dijon (France); Faculty of Medicine and Pharmacy, University of Burgundy, 21033 Dijon (France); Mezger, Valerie, E-mail: valerie.mezger@univ-paris-diderot.fr [CNRS, UMR7216 Epigenetics and Cell Fate, Paris (France); University Paris Diderot, 75013 Paris (France); Garrido, Carmen, E-mail: valerie.mezger@univ-paris-diderot.fr [INSERM U866, Dijon (France); Faculty of Medicine and Pharmacy, University of Burgundy, 21033 Dijon (France); CHU, Dijon BP1542, Dijon (France)

    2011-03-07

    Heat Shock Factors (HSF) form a family of transcription factors (four in mammals) which were named according to the discovery of their activation by a heat shock. HSFs trigger the expression of genes encoding Heat Shock Proteins (HSPs) that function as molecular chaperones, contributing to establish a cytoprotective state to various proteotoxic stresses and in pathological conditions. Increasing evidence indicates that this ancient transcriptional protective program acts genome-widely and performs unexpected functions in the absence of experimentally defined stress. Indeed, HSFs are able to re-shape cellular pathways controlling longevity, growth, metabolism and development. The most well studied HSF, HSF1, has been found at elevated levels in tumors with high metastatic potential and is associated with poor prognosis. This is partly explained by the above-mentioned cytoprotective (HSP-dependent) function that may enable cancer cells to adapt to the initial oncogenic stress and to support malignant transformation. Nevertheless, HSF1 operates as major multifaceted enhancers of tumorigenesis through, not only the induction of classical heat shock genes, but also of “non-classical” targets. Indeed, in cancer cells, HSF1 regulates genes involved in core cellular functions including proliferation, survival, migration, protein synthesis, signal transduction, and glucose metabolism, making HSF1 a very attractive target in cancer therapy. In this review, we describe the different physiological roles of HSFs as well as the recent discoveries in term of non-cogenic potential of these HSFs, more specifically associated to the activation of “non-classical” HSF target genes. We also present an update on the compounds with potent HSF1-modulating activity of potential interest as anti-cancer therapeutic agents.

  20. Transcriptome analysis of adaptive heat shock response of Streptococcus thermophilus.

    Directory of Open Access Journals (Sweden)

    Jin-song Li

    Full Text Available Streptococcus thermophilus, a gram-positive facultative anaerobe, is one of the most important lactic acid bacteria widely used in the dairy fermentation industry. In this study, we have analyzed the global transcriptional profiling of S. thermophilus upon temperature change. During a temperature shift from 42°C to 50°C, it is found that 196 (10.4% genes show differential expression with 102 up-regulated and 94 down-regulated at 50°C. In particular, 1 Heat shock genes, such as DnaK, GroESL and clpL, are identified to be elevated at 50°C; 2 Transcriptional regulators, such as HrcA, CtsR, Fur, MarR and MerR family, are differentially expressed, indicating the complex molecular mechanisms of S. thermophilus adapting to heat shock; 3 Genes associated with signal transduction, cell wall genes, iron homeostasis, ABC transporters and restriction-modification system were induced; 4 A large number of the differentially expressed genes are hypothetical genes of unknown function, indicating that much remains to be investigated about the heat shock response of S. thermophilus. Experimental investigation of selected heat shock gene ClpL shows that it plays an important role in the physiology of S. thermophilus at high temperature and meanwhile we confirmed ClpL as a member of the CtsR regulon. Overall, this study has contributed to the underlying adaptive molecular mechanisms of S. thermophilus upon temperature change and provides a basis for future in-depth functional studies.

  1. Transcriptional Modulation of Heat-Shock Protein Gene Expression

    OpenAIRE

    Anastasis Stephanou; Latchman, David S.

    2011-01-01

    Heat-shock proteins (Hsps) are molecular chaperones that are ubiquitously expressed but are also induced in cells exposed to stressful stimuli. Hsps have been implicated in the induction and propagation of several diseases. This paper focuses on regulatory factors that control the transcription of the genes encoding Hsps. We also highlight how distinct transcription factors are able to interact and modulate Hsps in different pathological states. Thus, a better understanding of the complex sig...

  2. Transcriptional modulation of heat-shock protein gene expression.

    OpenAIRE

    A. Stephanou; Latchman, D S

    2011-01-01

    Heat-shock proteins (Hsps) are molecular chaperones that are ubiquitously expressed but are also induced in cells exposed to stressful stimuli. Hsps have been implicated in the induction and propagation of several diseases. This paper focuses on regulatory factors that control the transcription of the genes encoding Hsps. We also highlight how distinct transcription factors are able to interact and modulate Hsps in different pathological states. Thus, a better understanding of the complex sig...

  3. Acquired Thermotolerance and Heat Shock Proteins in Thermophiles from the Three Phylogenetic Domains

    DEFF Research Database (Denmark)

    Trent, Jonathan D.; Gabrielsen, Mette; Jensen, Bo

    1994-01-01

    at 70 degrees C and heat shocked at 88 degrees C for 60 min showed thermotolerance at 95 degrees C, and Thermomyces lanuginosus grown at 50 degrees C and heat shocked at 55 degrees C for 60 min showed thermotolerance at 58 degrees C. Determinations of protein synthesis during heat shock revealed...... differences in the dominant heat shock proteins for each species. For B. caldolyticus, a 70-kDa protein dominated while for S. shibatae, a 55-kDa protein dominated and for T. lanuginosus, 31- to 33-kDa proteins dominated. Reagents that disrupted normal protein synthesis during heat shock prevented......Thermophilic organisms from each of the three phylogenetic domains (Bacteria, Archaea, and Eucarya) acquired thermotolerance after heat shock. Bacillus caldolyticus grown at 60 degrees C and heat shocked at 69 degrees C for 10 min showed thermotolerance at 74 degrees C, Sulfolobus shibatae grown...

  4. Competition between shock and turbulent heating in coronal loop system

    Science.gov (United States)

    Matsumoto, Takuma

    2016-11-01

    2.5-dimensional magnetohydrodynamic (MHD) simulations are performed with high spatial resolution in order to distinguish between competing models of the coronal heating problem. A single coronal loop powered by Alfvén waves excited in the photosphere is the target of this study. The coronal structure is reproduced in our simulations as a natural consequence of the transportation and dissipation of Alfvén waves. Further, the coronal structure is maintained as the spatial resolution is changed from 25 to 3 km, although the temperature at the loop top increases with the spatial resolution. The heating mechanisms change gradually across the magnetic canopy at a height of 4 Mm. Below the magnetic canopy, both the shock and the MHD turbulence are dominant heating processes. Above the magnetic canopy, the shock heating rate reduces to less than 10 per cent of the total heating rate while the MHD turbulence provides significant energy to balance the radiative cooling and thermal conduction loss or gain. The importance of compressibility shown in this study would significantly impact on the prospects of successful MHD turbulence theory in the solar chromosphere.

  5. Competition between shock and turbulent heating in coronal loop system

    CERN Document Server

    Matsumoto, Takuma

    2016-01-01

    2.5-dimensional magnetohydrodynamic (MHD) simulations are performed with high spatial resolution in order to distinguish between competing models of the coronal heating problem. A single coronal loop powered by Alfv\\'{e}n waves excited in the photosphere is the target of the present study. The coronal structure is reproduced in our simulations as a natural consequence of the transportation and dissipation of Alfv\\'{e}n waves. Further, the coronal structure is maintained as the spatial resolution is changed from 25 to 3 km, although the temperature at the loop top increases with the spatial resolution. The heating mechanisms change gradually across the magnetic canopy at a height of 4 Mm. Below the magnetic canopy, both the shock and the MHD turbulence are dominant heating processes. Above the magnetic canopy, the shock heating rate reduces to less than 10 % of the total heating rate while the MHD turbulence provides significant energy to balance the radiative cooling and thermal conduction loss or gain. The i...

  6. Heat shock proteins and heat therapy for type 2 diabetes: pros and cons.

    Science.gov (United States)

    Krause, Mauricio; Ludwig, Mirna Stela; Heck, Thiago Gomes; Takahashi, Hilton Kenji

    2015-07-01

    Heat therapy, such as sauna and hot tub, has become an increasingly regular therapeutical practice around the world since several studies have shown benefits of heat therapy in metabolic and cardiovascular diseases. The use of heat therapy in people with type 2 diabetes mellitus revealed a striking reduction of 1% unit in the glycated hemoglobin, suggesting this therapy for the treatment of diabetes. Herein, we shall discuss the use of heat therapy and the mechanisms involved, and suggest a provisional guide for the use of heat therapy in obesity and diabetes. Human studies indicate that heat therapy reduces fasting glycemia, glycated hemoglobin, body weight, and adiposity. Animal studies have indicated that nitric oxide and the increase in heat shock protein 70 expression is involved in the improvements induced by heat therapy on insulin sensitivity, adiposity, inflammation, and vasomotricity. Heat therapy is a promising and inexpensive tool for the treatment of obesity and diabetes. We proposed that transient increments in nitric oxide and heat shock protein 70 levels may explain the benefits of heat therapy. We suggest that heat therapy (sauna: 80-100°C; hot tub: at 40°C) for 15 min, three times a week, for 3 months, is a safe method to test its efficiency.

  7. Molecular communications between plant heat shock responses and disease resistance.

    Science.gov (United States)

    Lee, Jae-Hoon; Yun, Hye Sup; Kwon, Chian

    2012-08-01

    As sessile, plants are continuously exposed to potential dangers including various abiotic stresses and pathogen attack. Although most studies focus on plant responses under an ideal condition to a specific stimulus, plants in nature must cope with a variety of stimuli at the same time. This indicates that it is critical for plants to fine-control distinct signaling pathways temporally and spatially for simultaneous and effective responses to various stresses. Global warming is currently a big issue threatening the future of humans. Reponses to high temperature affect many physiological processes in plants including growth and disease resistance, resulting in decrease of crop yield. Although plant heat stress and defense responses share important mediators such as calcium ions and heat shock proteins, it is thought that high temperature generally suppresses plant immunity. We therefore specifically discuss on interactions between plant heat and defense responses in this review hopefully for an integrated understanding of these responses in plants.

  8. Effect of heat release on movement characteristics of shock train in an isolator

    Science.gov (United States)

    Zhang, Chenlin; Chang, Juntao; Liu, MengMeng; Feng, Shuo; Shi, Wen; Bao, Wen

    2017-04-01

    In this paper, the effect of heat release on movement characteristics of shock train is numerically investigated in an isolator. It is found that the combustion heat release has a distinct effect on the shock train movement characteristics in the isolator. With increasing heat release, a shock train gradually forms and then propagates toward isolator entrance. In process of shock train formation, separation bubbles before injection ports entrain the high temperature burning gas into the boundary layer, which causes the shock train to shrink and stretch, and changes in configuration and number of shock waves. At the same time, the system force fluctuates. In addition, the shock train movement is divided into three stages, which have different wall pressure distribution. It is believed that these findings have a help the better understanding of the effect of heat release on the movement characteristics of shock train in an isolator.

  9. Global transcriptome analysis of the heat shock response ofshewanella oneidensis

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Haichun; Wang, Sarah; Liu, Xueduan; Yan, Tinfeng; Wu, Liyou; Alm, Eric; Arkin, Adam P.; Thompson, Dorothea K.; Zhou, Jizhong

    2004-04-30

    Shewanella oneidensis is an important model organism for bioremediation studies because of its diverse respiratory capabilities. However, the genetic basis and regulatory mechanisms underlying the ability of S. oneidensis to survive and adapt to various environmentally relevant stresses is poorly understood. To define this organism's molecular response to elevated growth temperatures, temporal gene expression profiles were examined in cells subjected to heat stress using whole-genome DNA microarrays for S. oneidensis MR-1. Approximately 15 percent (711) of the predicted S. oneidensis genes represented on the microarray were significantly up- or down-regulated (P < 0.05) over a 25-min period following shift to the heat shock temperature (42 C). As expected, the majority of S. oneidensis genes exhibiting homology to known chaperones and heat shock proteins (Hsps) were highly and transiently induced. In addition, a number of predicted genes encoding enzymes in glycolys is and the pentose cycle, [NiFe] dehydrogenase, serine proteases, transcriptional regulators (MerR, LysR, and TetR families), histidine kinases, and hypothetical proteins were induced in response to heat stress. Genes encoding membrane proteins were differentially expressed, suggesting that cells possibly alter their membrane composition or structure in response to variations in growth temperature. A substantial number of the genes encoding ribosomal proteins displayed down-regulated co-expression patterns in response to heat stress, as did genes encoding prophage and flagellar proteins. Finally, based on computational comparative analysis of the upstream promoter regions of S.oneidensis heat-inducible genes, a putative regulatory motif, showing high conservation to the Escherichia coli sigma 32-binding consensus sequence, was identified.

  10. Gene Expression Profiling of Clostridium botulinum under Heat Shock Stress

    Directory of Open Access Journals (Sweden)

    Wan-dong Liang

    2013-01-01

    Full Text Available During growth, C. botulinum is always exposed to different environmental changes, such as temperature increase, nutrient deprivation, and pH change; however, its corresponding global transcriptional profile is uncharacterized. This study is the first description of the genome-wide gene expression profile of C. botulinum in response to heat shock stress. Under heat stress (temperature shift from 37°C to 45°C over a period of 15 min, 176 C. botulinum ATCC 3502 genes were differentially expressed. The response included overexpression of heat shock protein genes (dnaK operon, groESL, hsp20, and htpG and downregulation of aminoacyl-tRNA synthetase genes (valS, queA, tyrR, and gatAB and ribosomal and cell division protein genes (ftsZ and ftsH. In parallel, several transcriptional regulators (marR, merR, and ompR families were induced, suggesting their involvement in reshuffling of the gene expression profile. In addition, many ABC transporters (oligopeptide transport system, energy production and conversion related genes (glpA and hupL, cell wall and membrane biogenesis related genes (fabZ, fabF, and fabG, flagella-associated genes (flhA, flhM, flhJ, flhS, and motAB, and hypothetical genes also showed changed expression patterns, indicating that they may play important roles in survival under high temperatures.

  11. A hypothesis for the evolution of nuclear-encoded, plastid-targeted glyceraldehyde-3-phosphate dehydrogenase genes in "chromalveolate" members.

    Directory of Open Access Journals (Sweden)

    Kiyotaka Takishita

    Full Text Available Eukaryotes bearing red alga-derived plastids--photosynthetic alveolates (dinoflagellates plus the apicomplexan Toxoplasma gondii plus the chromerid Chromera velia, photosynthetic stramenopiles, haptophytes, and cryptophytes--possess unique plastid-targeted glyceraldehyde-3-phosphate dehydrogenases (henceforth designated as "GapC1". Pioneering phylogenetic studies have indicated a single origin of the GapC1 enzymes in eukaryotic evolution, but there are two potential idiosyncrasies in the GapC1 phylogeny: Firstly, the GapC1 tree topology is apparently inconsistent with the organismal relationship among the "GapC1-containing" groups. Secondly, four stramenopile GapC1 homologues are consistently paraphyletic in previously published studies, although these organisms have been widely accepted as monophyletic. For a closer examination of the above issues, in this study GapC1 gene sampling was improved by determining/identifying nine stramenopile and two cryptophyte genes. Phylogenetic analyses of our GapC1 dataset, which is particularly rich in the stramenopile homologues, prompt us to propose a new scenario that assumes multiple, lateral GapC1 gene transfer events to explain the incongruity between the GapC1 phylogeny and the organismal relationships amongst the "GapC1-containing" groups. Under our new scenario, GapC1 genes uniquely found in photosynthetic alveolates, photosynthetic stramenopiles, haptophytes, and cryptopyhytes are not necessarily a character vertically inherited from a common ancestor.

  12. Effect of heat shock protein 70 on cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Wen Yan; Xiulian Chen; Rui Chen; Shiming Xu; Lijuan Zhang; Hongjuan Wang; Chunyue Huo

    2006-01-01

    OBJECTIVE: To summarize the relationship between heat shock protein 70 (HSP70) and cerebral ischemia.DATA SOURCES: An online search of Medline database was undertaken to identify relevant articles published in English from January 1980 to December 2005 by using the keywords of "heat shock protein 70, ischemia". Meanwhile, Chinese relevant articles published from January 2000 to December 2005 were searched in China National Knowledge Infrastructure (CNKI) database and Chinese Journal of Clinical Rehabilitation with the keywords of "heat shock protein 70, cerebral ischemia" in Chinese.STUDY SELECTION: More than 100 related articles were screened, and 29 references mainly about HSP70and cerebral ischemia were selected, including basic and clinical researches. As to the articles with similar content, those published in the authoritative journals in recent 3 years were preferential.DATA EXTRACTION : A total of 29 articles were collected and classified according to the structure, function and clinical application of HSP70. Among them, 1 article is about the structure of HSP70, 27 about the relationship between HSP70 and cerebral ischemia, and 2 about the clinical application of HSP70.DATA SYNTHESTS: HSP70 is one of the most conservative proteins during biological evolution. Experiments in cerebral ischemia revealed that HSP70 expression was time-dependent, also correlated with the injured site and severity. The cerebral ischemia induced HSP70 gene expression in hippocampus of gerbil had protection to tolerance of fatal ischemic injury for neurons. The increase of HSP70 expression may be one of the endogenous protective mechanisms during cerebral ischemia, and can effectively alleviate cerebral ischemia. Thus HSP70 protein and HSP70 mRNA have been taken as important indexes extensively applied in the basic study of cerebral ischemia by some scholars abroad.CONCLUSTON: HSP70 plays a protective role in cerebral ischemia, and a deeper research into the biological function of

  13. Associations between heat shock protein 70 genetic polymorphisms and calving traits in crossbred Brahman cows

    Science.gov (United States)

    Stressors such as heat, cold, toxins, and oxygen deprivation are known to induce heat shock proteins. Genetic polymorphisms associated with heat shock protein genes have been associated with decreased male and female fertility. Our objectives were to 1) confirm single nucleotide polymorphisms (SNP) ...

  14. Transcriptional Modulation of Heat-Shock Protein Gene Expression

    Directory of Open Access Journals (Sweden)

    Anastasis Stephanou

    2011-01-01

    Full Text Available Heat-shock proteins (Hsps are molecular chaperones that are ubiquitously expressed but are also induced in cells exposed to stressful stimuli. Hsps have been implicated in the induction and propagation of several diseases. This paper focuses on regulatory factors that control the transcription of the genes encoding Hsps. We also highlight how distinct transcription factors are able to interact and modulate Hsps in different pathological states. Thus, a better understanding of the complex signaling pathways regulating Hsp expression may lead to novel therapeutic targets.

  15. Transcriptional modulation of heat-shock protein gene expression.

    Science.gov (United States)

    Stephanou, Anastasis; Latchman, David S

    2011-01-01

    Heat-shock proteins (Hsps) are molecular chaperones that are ubiquitously expressed but are also induced in cells exposed to stressful stimuli. Hsps have been implicated in the induction and propagation of several diseases. This paper focuses on regulatory factors that control the transcription of the genes encoding Hsps. We also highlight how distinct transcription factors are able to interact and modulate Hsps in different pathological states. Thus, a better understanding of the complex signaling pathways regulating Hsp expression may lead to novel therapeutic targets.

  16. Heat shock proteiners inhibering af programmeret celledød

    OpenAIRE

    Cohen, Malene; Jantzen, Kim; Olsson, Kim; Rohde, Anders

    2007-01-01

    Heat shock proteiner (Hsp) har i de seneste år været genstand for interesse indenfor forskellige grene af biologien på grund af deres egenskaber indenfor programmeret celledød. Den etablerede viden er størst indenfor oncologi, hvor Hsps apoptosehæmmende egenskaber fortsat er genstand for forskning, men proteinernes præventive effekt på toksin- eller stressinduceret celledød har spredt interessen til felter som neurologi og toksologi. Målet med denne rapport har været at sammenf...

  17. Destabilization and recovery of a yeast prion after mild heat shock

    OpenAIRE

    Newnam, Gary P.; Birchmore, Jennifer L.; Chernoff, Yury O.

    2011-01-01

    Yeast prion [PSI+] is a self-perpetuating amyloid of the translational termination factor Sup35. Although [PSI+] propagation is modulated by heat shock proteins (Hsps), high temperature was previously reported to have little or no effect on [PSI+]. Our results show that short-term exposure of exponentially growing yeast culture to mild heat shock, followed by immediate resumption of growth, leads to [PSI+] destabilization, sometimes persisting for several cell divisions after heat shock. Prio...

  18. Intra-Binary Shock Heating of Black Widow Companions

    CERN Document Server

    Romani, Roger W

    2016-01-01

    The low mass companions of evaporating binary pulsars (black widows and their ilk) are strongly heated on the side facing the pulsar. However in high-quality photometric and spectroscopic data the heating pattern does not match that expected for direct pulsar illumination. Here we explore heating mediated by an intra-binary shock (IBS). We develop a simple analytic model and implement it in the popular `ICARUS' light curve code. The model is parameterized by the wind momentum ratio beta and velocity v_Rel v_orb and assumes that the reprocessed pulsar wind emits prompt particles or radiation to heat the companion surface. We illustrate an interesting range of light curve asymmetries controlled by these parameters. The code also computes the IBS synchrotron emission pattern, and thus can model black widow X-ray light curves. As a test we apply the results to the high quality asymmetric optical light curves of PSR J2215+5135; the resulting fit gives a substantial improvement upon direct heating models and produc...

  19. The L-type cyclin CYL-1 and the heat-shock-factor HSF-1 are required for heat-shock-induced protein expression in Caenorhabditis elegans.

    Science.gov (United States)

    Hajdu-Cronin, Yvonne M; Chen, Wen J; Sternberg, Paul W

    2004-12-01

    In a screen for suppressors of activated GOA-1 (Galpha(o)) under the control of the hsp-16.2 heat-shock promoter, we identified three genetic loci that affected heat-shock-induced GOA-1 expression. The cyl-1 mutants are essentially wild type in appearance, while hsf-1 and sup-45 mutants have egg-laying defects. The hsf-1 mutation also causes a temperature-sensitive developmental arrest, and hsf-1 mutants have decreased life span. Western analysis indicated that mutations in all three loci suppressed the activated GOA-1 transgene by decreasing its expression. Heat-shock-induced expression of hsp-16.2 mRNA was reduced in cyl-1 mutants and virtually eliminated in hsf-1 and sup-45 mutants, as compared to wild-type expression. The mutations could also suppress other transgenes under heat-shock control. cyl-1 and sup-45, but not hsf-1, mutations suppressed a defect caused by a transgene not under heat-shock control, suggesting a role in general transcription or a post-transcriptional aspect of gene expression. hsf-1 encodes the C. elegans homolog of the human heat-shock factor HSF1, and cyl-1 encodes a cyclin most similar to cyclin L. We believe HSF-1 acts in heat-shock-inducible transcription and CYL-1 acts more generally in gene expression.

  20. Effect of viscosity and wall heat conduction on shock attenuation in narrow channels

    Science.gov (United States)

    Deshpande, A.; Puranik, B.

    2016-07-01

    In the present work, the effects due to viscosity and wall heat conduction on shock propagation and attenuation in narrow channels are numerically investigated. A two-dimensional viscous shock tube configuration is simulated, and heat conduction in the channel walls is explicitly included. The simulation results indicate that the shock attenuation is significantly less in the case of an adiabatic wall, and the use of an isothermal wall model is adequate to take into account the wall heat conduction. A parametric study is performed to characterize the effects of viscous forces and wall heat conduction on shock attenuation, and the behaviour is explained on the basis of boundary layer formation in the post-shock region. A dimensionless parameter that describes the shock attenuation is correlated with the diaphragm pressure ratio and a dimensionless parameter which is expressed using the characteristic Reynolds number and the dimensionless shock travel.

  1. Exploring temporal transcription regulation structure of Aspergillus fumigatus in heat shock by state space model

    Directory of Open Access Journals (Sweden)

    Miyano Satoru

    2009-07-01

    Full Text Available Abstract Background The thermotolerance of Aspergillus fumigatus plays a critical role in mammalian and avian infections. Thus, the identification of its adaptation mechanism to higher temperature is very important for an efficient anti-fungal drug development as well as fundamental understanding of its pathogenesis. We explored the temporal transcription regulation structure of this pathogenic fungus under heat shock conditions using the time series microarray data reported by Nierman et al. (Nature 2005, 438:1151-1156. Results The estimated transcription regulation structure of A. fumigatus shows that the heat shock proteins are strongly negatively associated with central metabolic pathway genes such as the tricarboxylic acid cycle (TCA cycle and carbohydrate metabolism. It was 60 min and 120 min, respectively, after the growth temperature changes from 30°C (corresponding to environments of tropical soil to 37°C and 48°C (corresponding to temperatures in the human body and compost, respectively that some of genes in TCA cycle were started to be upregulated. In these points, most of heat shock proteins showed lowest expression level after heat shocks. Among the heat shock proteins, the HSP30 (AFU6G06470, a single integral plasma membrane heat shock protein, presented most active role in transcription regulation structure in both heat shock conditions of 37°C and 48°C. The metabolic genes associated with multiple genes in the gene regulation network showed a tendency to have opposite expression patterns of heat shock proteins. The role of those metabolic genes was second regulator in the coherent feed-forward loop type of regulation structure having heat shock protein as its first regulator. This type of regulation structure might be very advantageous for the thermal adaptation of A. fumigatus under heat shock because a small amount of heat shock proteins can rapidly magnify their regulation effect on target genes. However, the coherent

  2. Heat shock-induced interactions among nuclear HSFs detected by fluorescence cross-correlation spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Pack, Chan-Gi, E-mail: changipack@amc.seoul.kr [Asan Institute for Life Sciences, University of Ulsan, College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Ahn, Sang-Gun [Dept. of Pathology, College of Dentistry, Chosun University, Seosuk-dong, Dong-gu, Gwangju 501-759 (Korea, Republic of)

    2015-07-31

    The cellular response to stress is primarily controlled in cells via transcriptional activation by heat shock factor 1 (HSF1). HSF1 is well-known to form homotrimers for activation upon heat shock and subsequently bind to target DNAs, such as heat-shock elements, by forming stress granules. A previous study demonstrated that nuclear HSF1 and HSF2 molecules in live cells interacted with target DNAs on the stress granules. However, the process underlying the binding interactions of HSF family in cells upon heat shock remains unclear. This study demonstrate for the first time that the interaction kinetics among nuclear HSF1, HSF2, and HSF4 upon heat shock can be detected directly in live cells using dual color fluorescence cross-correlation spectroscopy (FCCS). FCCS analyses indicated that the binding between HSFs was dramatically changed by heat shock. Interestingly, the recovery kinetics of interaction between HSF1 molecules after heat shock could be represented by changes in the relative interaction amplitude and mobility. - Highlights: • The binding interactions among nuclear HSFs were successfully detected. • The binding kinetics between HSF1s during recovery was quantified. • HSF2 and HSF4 strongly formed hetero-complex, even before heat shock. • Nuclear HSF2 and HSF4 bound to HSF1 only after heat shock.

  3. Heat-shock-induced cellular responses to temperature elevations occurring during orthopaedic cutting

    OpenAIRE

    Dolan, E. B.; Haugh, M. G.; Tallon, D.; Casey, C.; McNamara, L.M.

    2012-01-01

    Severe heat-shock to bone cells caused during orthopaedic procedures can result in thermal damage, leading to cell death and initiating bone resorption. By contrast, mild heat-shock has been proposed to induce bone regeneration. In this study, bone cells are exposed to heat-shock for short durations occurring during surgical cutting. Cellular viability, necrosis and apoptosis are investigated immediately after heat-shock and following recovery of 12, 24 h and 4 days, in osteocyte-like MLO-Y4 ...

  4. The central role of heat shock factor 1 in synaptic fidelity and memory consolidation

    National Research Council Canada - National Science Library

    Hooper, Philip L; Durham, Heather D; Török, Zsolt; Hooper, Paul L; Crul, Tim; Vígh, László

    2016-01-01

    ...), the major transcription factor regulating expression of heat shock genes, plays a central role in proteostasis, in establishing and sustaining synaptic fidelity and function, and in memory consolidation...

  5. KPNA3-knockdown eliminates the second heat shock protein peak associated with the heat shock response of male silkworm pupae (Bombyx mori) by reducing heat shock factor transport into the nucleus.

    Science.gov (United States)

    Li, Jun; Wei, Guoqing; Wang, Lei; Qian, Cen; Li, Kedong; Zhang, Congfen; Dai, Lishang; Sun, Yu; Liu, Dongran; Zhu, Baojian; Liu, Chaoliang

    2016-01-10

    In this study, we investigated the role of karyopherin alpha 3 in the heat shock response in male silkworm pupae. Karyopherin alpha recognizes the classical nuclear location sequence on proteins and transports them into the nucleus by forming a trimetric complex with karyopherin beta. Three predicted karyopherin alphas (KPNA1, KPNA2 and KPNA3) have been identified from the silkworm Bombyx mori. Pull-down assay result showed that KPNA3 can pull down heat shock transcription factor (HSF) from proteins extracted from tissues using non-denature lysis buffer. After 45 °C heat shock on male B. mori pupae for 30 min, we identified two heat shock protein (HSP) mRNA expression peaks correlating with HSP19.9, HSP20.4 and HSP25.4 at 4 h (peak 1) and 24 h (peak 2). The second peak was eliminated after knockdown of KPNA3. Similar results were obtained following knockdown of HSF, which is the trans-activating factor of heat shock. However, KPNA3 knockdown was not accompanied by the decreased HSF protein levels at 24 h after heat shock which were observed following HSF knockdown. We also expressed recombinant protein GST-KPNA3 and His-HSF in Escherichia coli to perform GST pull-down assay and the result confirmed the interaction between KPNA3 and HSF. We concluded that KPNA3 knockdown eliminates the second heat shock protein peak in the heat shock response of male silkworm pupae by reducing HSF transport into the nucleus.

  6. Heat Shock Protein 96 Induces Maturation of Dendritic Cells

    Institute of Scientific and Technical Information of China (English)

    Chunxia Cao; Wei Yang; Yonglie Chu; Qingguang Liu; Liang Yu; Cheng'en Pan

    2006-01-01

    Objective: Heat shock protein (HSP) has the promiscuous abilities to chaperone and present a broad repertoire of tumor antigens to antigen presenting cells including DCs. In this report, we analyzed the modulation of immature DC by HSP 96 (gp96).Method: Murine bone marrow-derived DC was induced by GM-CSF plus IL-4, which aped the immunostimulatory effects of DC.Cocultured DC and gp96-peptide complexes (gp96-PC) or inactivated H22 cells, the expression of MHC class Ⅱ, CD40, CD80 was quantified by flow cytometry. The concentration of IL-12 and TNF- in culture supernatants were determined by ELISA.[51] Cr release assay was used to test specific cytotoxic T cell. Results: Our study demonstrated that the extent of DC maturation induced by gp96-PC, which was reflected in surface density of costimulatory and MHC Ⅱ molecules, was correlated with the secretion of IL-12 and with the T cellactivating potential in vitro. Conclusion: Heat shock protein 96 could be isolated and purified from H22 cells and could induce maturation of dendritic cell. Our findings might be relevance to the use of DC vaccine in therapy of human tumors.

  7. Modification of tooth development by heat shock protein 60

    Institute of Scientific and Technical Information of China (English)

    Tamas Papp; Angela Polyak; Krisztina Papp; Zoltan Meszar; Roza Zakany; Eva Meszar-Katona; Palne Terdik Tu nde; Chang Hwa Ham; Szabolcs Felszeghy

    2016-01-01

    Although several heat shock proteins have been investigated in relation to tooth development, no available information is available about the spatial and temporal expression pattern of heat shock protein 60 (Hsp 60). To characterize Hsp 60 expression in the structures of the developing tooth germ, we used Western blotting, immunohistochemistry and in situ hybridization. Hsp 60 was present in high amounts in the inner and outer enamel epithelia, enamel knot (EK) and stratum intermedium (SI). Hsp 60 also appeared in odontoblasts beginning in the bell stage. To obtain data on the possible effect of Hsp 60 on isolated lower incisors from mice, we performed in vitro culturing. To investigate the effect of exogenous Hsp 60 on the cell cycle during culturing, we used the 5-bromo-2- deoxyuridine (BrdU) incorporation test on dental cells. Exogenously administered Hsp 60 caused bluntness at the apical part of the 16.5-day-old tooth germs, but it did not influence the proliferation rate of dental cells. We identified the expression of Hsp 60 in the developing tooth germ, which was present in high concentrations in the inner and outer enamel epithelia, EK, SI and odontoblasts. High concentration of exogenous Hsp 60 can cause abnormal morphology of the tooth germ, but it did not influence the proliferation rate of the dental cells. Our results suggest that increased levels of Hsp 60 may cause abnormalities in the morphological development of the tooth germ and support the data on the significance of Hsp during the developmental processes.

  8. Modification of tooth development by heat shock protein 60.

    Science.gov (United States)

    Papp, Tamas; Polyak, Angela; Papp, Krisztina; Meszar, Zoltan; Zakany, Roza; Meszar-Katona, Eva; Tünde, Palne Terdik; Ham, Chang Hwa; Felszeghy, Szabolcs

    2016-03-30

    Although several heat shock proteins have been investigated in relation to tooth development, no available information is available about the spatial and temporal expression pattern of heat shock protein 60 (Hsp 60). To characterize Hsp 60 expression in the structures of the developing tooth germ, we used Western blotting, immunohistochemistry and in situ hybridization. Hsp 60 was present in high amounts in the inner and outer enamel epithelia, enamel knot (EK) and stratum intermedium (SI). Hsp 60 also appeared in odontoblasts beginning in the bell stage. To obtain data on the possible effect of Hsp 60 on isolated lower incisors from mice, we performed in vitro culturing. To investigate the effect of exogenous Hsp 60 on the cell cycle during culturing, we used the 5-bromo-2-deoxyuridine (BrdU) incorporation test on dental cells. Exogenously administered Hsp 60 caused bluntness at the apical part of the 16.5-day-old tooth germs, but it did not influence the proliferation rate of dental cells. We identified the expression of Hsp 60 in the developing tooth germ, which was present in high concentrations in the inner and outer enamel epithelia, EK, SI and odontoblasts. High concentration of exogenous Hsp 60 can cause abnormal morphology of the tooth germ, but it did not influence the proliferation rate of the dental cells. Our results suggest that increased levels of Hsp 60 may cause abnormalities in the morphological development of the tooth germ and support the data on the significance of Hsp during the developmental processes.

  9. Heat shock protein 90 from neglected protozoan parasites.

    Science.gov (United States)

    Roy, Nainita; Nageshan, Rishi Kumar; Ranade, Shatakshi; Tatu, Utpal

    2012-03-01

    Significant advances have been made in our understanding of heat shock protein 90 (Hsp90) in terms of its structure, biochemical characteristics, post-translational modifications, interactomes, regulation and functions. In addition to yeast as a model several new systems have now been examined including flies, worms, plants as well as mammalian cells. This review discusses themes emerging out of studies reported on Hsp90 from infectious disease causing protozoa. A common theme of sensing and responding to host cell microenvironment emerges out of analysis of Hsp90 in Malaria, Trypanosmiasis as well as Leishmaniasis. In addition to their functional roles, the potential of Hsp90 from these infectious disease causing organisms to serve as drug targets and the current status of this drug development endeavor are discussed. Finally, a unique and the only known example of a split Hsp90 gene from another disease causing protozoan Giardia lamblia and its evolutionary significance are discussed. Clearly studies on Hsp90 from protozoan parasites promise to reveal important new paradigms in Hsp90 biology while exploring its potential as an anti-infective drug target. This article is part of a Special Issue entitled: Heat Shock Protein 90 (HSP90). Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Protein disorder reduced in Saccharomyces cerevisiae to survive heat shock

    Science.gov (United States)

    Vicedo, Esmeralda; Gasik, Zofia; Dong, Yu-An; Goldberg, Tatyana; Rost, Burkhard

    2015-01-01

    Recent experiments established that a culture of Saccharomyces cerevisiae (baker’s yeast) survives sudden high temperatures by specifically duplicating the entire chromosome III and two chromosomal fragments (from IV and XII). Heat shock proteins (HSPs) are not significantly over-abundant in the duplication. In contrast, we suggest a simple algorithm to “ postdict ” the experimental results: Find a small enough chromosome with minimal protein disorder and duplicate this region. This algorithm largely explains all observed duplications. In particular, all regions duplicated in the experiment reduced the overall content of protein disorder. The differential analysis of the functional makeup of the duplication remained inconclusive. Gene Ontology (GO) enrichment suggested over-representation in processes related to reproduction and nutrient uptake. Analyzing the protein-protein interaction network (PPI) revealed that few network-central proteins were duplicated. The predictive hypothesis hinges upon the concept of reducing proteins with long regions of disorder in order to become less sensitive to heat shock attack. PMID:26673203

  11. Heat shock response and insulin-associated neurodegeneration.

    Science.gov (United States)

    Urban, Michael J; Dobrowsky, Rick T; Blagg, Brian S J

    2012-03-01

    Dysfunctional insulin and insulin-like growth factor-I (IGF-I) signaling contributes to the pathological progression of diabetes, diabetic peripheral neuropathy (DPN), Alzheimer's (AD), Parkinson's (PD) and Huntington's diseases (HD). Despite their prevalence, there are limited therapeutic options available for the treatment of these neurodegenerative disorders. Therefore, establishing a link between insulin/IGF-I and the pathoetiology of these diseases may provide alternative approaches toward their management. Many of the heat shock proteins (Hsps) are well-known molecular chaperones that solubilize and clear damaged proteins and protein aggregates. Recent studies suggest that modulating Hsps may represent a promising therapeutic avenue for improving insulin and IGF-I signaling. Pharmacological induction of the heat shock response (HSR) may intersect with insulin/IGF-I signaling to improve aspects of neurodegenerative phenotypes. Herein, we review the intersection between Hsps and the insulin/IGF systems under normal and pathological conditions. The discussion will emphasize the potential of non-toxic HSR inducers as viable therapeutic agents.

  12. Differential expression of heat shock transcription factors and heat shock proteins after acute and chronic heat stress in laying chickens (Gallus gallus).

    Science.gov (United States)

    Xie, Jingjing; Tang, Li; Lu, Lin; Zhang, Liyang; Xi, Lin; Liu, Hsiao-Ching; Odle, Jack; Luo, Xugang

    2014-01-01

    Heat stress due to high environmental temperature negatively influences animal performances. To better understand the biological impact of heat stress, laying broiler breeder chickens were subjected either to acute (step-wisely increasing temperature from 21 to 35°C within 24 hours) or chronic (32°C for 8 weeks) high temperature exposure. High temperature challenges significantly elevated body temperature of experimental birds (Pheat shock transcription factors (HSFs) and heat shock proteins (HSPs) 70 and 90 were differently affected by acute and chronic treatment. Tissue-specific responses to thermal challenge were also found among heart, liver and muscle. In the heart, acute heat challenge affected lipid oxidation (P = 0.05) and gene expression of all 4 HSF gene expression was upregulated (Pheat treatment, the HSP 70 mRNA level was increased (Pheat challenge (Pheat stress increased protein oxidation, but HSFs and HSPs gene expression remained unaltered. Only tendencies to increase were observed in HSP 70 (P = 0.052) and 90 (P = 0.054) gene expression after acute heat stress. The differential expressions of HSF and HSP genes in different tissues of laying broiler breeder chickens suggested that anti-heat stress mechanisms might be provoked more profoundly in the heart, by which the muscle was least protected during heat stress. In addition to HSP, HSFs gene expression could be used as a marker during acute heat stress.

  13. Heat-shock protein 70 binds microtubules and interacts with kinesin in tobacco pollen tubes.

    Science.gov (United States)

    Parrotta, Luigi; Cresti, Mauro; Cai, Giampiero

    2013-09-01

    The heat-shock proteins of 70 kDa are a family of ubiquitously expressed proteins important for protein folding. Heat-shock protein 70 assists other nascent proteins to achieve the spatial structure and ultimately helps the cell to protect against stress factors, such as heat. These proteins are localized in different cellular compartments and are associated with the cytoskeleton. We identified a heat-shock protein 70 isoform in the pollen tube of tobacco that binds to microtubules in an ATP-dependent manner. The heat-shock protein 70 was identified as part of the so-called ATP-MAP (ATP-dependent microtubule-associated protein) fraction, which also includes the 90-kDa kinesin, a mitochondria-associated motor protein. The identity of heat-shock protein 70 was validated by immunological assays and mass spectrometry. Sequence analysis showed that this heat-shock protein 70 is more similar to specific heat-shock proteins of Arabidopsis than to corresponding proteins of tobacco. Two-dimensional electrophoresis indicated that this heat-shock protein 70 isoform only is part of the ATP-MAP fraction and that is associated with the mitochondria of pollen tubes. Sedimentation assays showed that the binding of heat-shock protein 70 to microtubules is not affected by AMPPNP but it increases in the presence of the 90-kDa kinesin. Binding of heat-shock protein 70 to microtubules occurs only partially in the presence of ATP but it does not occur if, in addition to ATP, the 90-kDa kinesin is also present. Data suggest that the binding (but not the release) of heat-shock protein 70 to microtubules is facilitated by the 90-kDa kinesin.

  14. Differential expression of heat shock transcription factors and heat shock proteins after acute and chronic heat stress in laying chickens (Gallus gallus.

    Directory of Open Access Journals (Sweden)

    Jingjing Xie

    Full Text Available Heat stress due to high environmental temperature negatively influences animal performances. To better understand the biological impact of heat stress, laying broiler breeder chickens were subjected either to acute (step-wisely increasing temperature from 21 to 35°C within 24 hours or chronic (32°C for 8 weeks high temperature exposure. High temperature challenges significantly elevated body temperature of experimental birds (P<0.05. However, oxidation status of lipid and protein and expression of heat shock transcription factors (HSFs and heat shock proteins (HSPs 70 and 90 were differently affected by acute and chronic treatment. Tissue-specific responses to thermal challenge were also found among heart, liver and muscle. In the heart, acute heat challenge affected lipid oxidation (P = 0.05 and gene expression of all 4 HSF gene expression was upregulated (P<0.05. During chronic heat treatment, the HSP 70 mRNA level was increased (P<0.05 and HSP 90 mRNA (P<0.05 was decreased. In the liver, oxidation of protein was alleviated during acute heat challenge (P<0.05, however, gene expression HSF2, 3 and 4 and HSP 70 were highly induced (P<0.05. HSP90 expression was increased by chronic thermal treatment (P<0.05. In the muscle, both types of heat stress increased protein oxidation, but HSFs and HSPs gene expression remained unaltered. Only tendencies to increase were observed in HSP 70 (P = 0.052 and 90 (P = 0.054 gene expression after acute heat stress. The differential expressions of HSF and HSP genes in different tissues of laying broiler breeder chickens suggested that anti-heat stress mechanisms might be provoked more profoundly in the heart, by which the muscle was least protected during heat stress. In addition to HSP, HSFs gene expression could be used as a marker during acute heat stress.

  15. Functional divergence and convergent evolution in the plastid-targeted glyceraldehyde-3-phosphate dehydrogenases of diverse eukaryotic algae.

    Science.gov (United States)

    Gaston, Daniel; Roger, Andrew J

    2013-01-01

    Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a key enzyme of the glycolytic pathway, reversibly catalyzing the sixth step of glycolysis and concurrently reducing the coenzyme NAD(+) to NADH. In photosynthetic organisms a GAPDH paralog (Gap2 in Cyanobacteria, GapA in most photosynthetic eukaryotes) functions in the Calvin cycle, performing the reverse of the glycolytic reaction and using the coenzyme NADPH preferentially. In a number of photosynthetic eukaryotes that acquired their plastid by the secondary endosymbiosis of a eukaryotic red alga (Alveolates, haptophytes, cryptomonads and stramenopiles) GapA has been apparently replaced with a paralog of the host's own cytosolic GAPDH (GapC1). Plastid GapC1 and GapA therefore represent two independent cases of functional divergence and adaptations to the Calvin cycle entailing a shift in subcellular targeting and a shift in binding preference from NAD(+) to NADPH. We used the programs FunDi, GroupSim, and Difference Evolutionary-Trace to detect sites involved in the functional divergence of these two groups of GAPDH sequences and to identify potential cases of convergent evolution in the Calvin-cycle adapted GapA and GapC1 families. Sites identified as being functionally divergent by all or some of these programs were then investigated with respect to their possible roles in the structure and function of both glycolytic and plastid-targeted GAPDH isoforms. In this work we found substantial evidence for convergent evolution in GapA/B and GapC1. In many cases sites in GAPDHs of these groups converged on identical amino acid residues in specific positions of the protein known to play a role in the function and regulation of plastid-functioning enzymes relative to their cytosolic counterparts. In addition, we demonstrate that bioinformatic software like FunDi are important tools for the generation of meaningful biological hypotheses that can then be tested with direct experimental techniques.

  16. Examination of KNK437- and quercetin-mediated inhibition of heat shock-induced heat shock protein gene expression in Xenopus laevis cultured cells.

    Science.gov (United States)

    Manwell, Laurie A; Heikkila, John J

    2007-11-01

    We examined the effect of quercetin (3,3',4',5,7-pentahydroxyflavon) and KNK437 (N-formyl-3,4-methylenedioxy-benzylidene-gamma-butyrolactam), a benzylidene lactam compound, on heat-induced heat shock protein (hsp) gene expression in Xenopus laevis A6 kidney epithelial cells. In previous studies, both quercetin and KNK437 inhibited heat shock factor activity resulting in a repression of hsp mRNA and protein accumulation in human cultured cells. In this first study of the effect of these hsp gene expression inhibitors in a non-mammalian cell line, we report that both quercetin and KNK437 reduced the heat shock-induced accumulation of hsp30, hsp47 and hsp70 mRNA in X. laevis cultured cells. However, these inhibitors had no effect on the relative level of a non-heat shock protein mRNA, ef1alpha, in either control or heat shocked cells. Western blot and immunocytochemical analyses revealed that quercetin partially inhibited HSP30 protein accumulation. In contrast, HSP30 protein was not detectable in KNK437-treated cells. Finally, treatment of A6 cells with KNK437 inhibited the heat shock-induced acquisition of thermotolerance, as determined by preservation of actin filaments and cellular morphology using immunocytochemistry and laser scanning confocal microscopy.

  17. Heat-shock protein 27 (Hsp27) as a target of methylglyoxal in gastrointestinal cancer.

    Science.gov (United States)

    Oya-Ito, Tomoko; Naito, Yuji; Takagi, Tomohisa; Handa, Osamu; Matsui, Hirofumi; Yamada, Masaki; Shima, Keisuke; Yoshikawa, Toshikazu

    2011-07-01

    The molecular mechanisms underlying the posttranslational modification of proteins in gastrointestinal cancer are still unknown. Here, we investigated the role of methylglyoxal modifications in gastrointestinal tumors. Methylglyoxal is a reactive dicarbonyl compound produced from cellular glycolytic intermediates that reacts non-enzymatically with proteins. By using a monoclonal antibody to methylglyoxal-modified proteins, we found that murine heat-shock protein 25 and human heat-shock protein 27 were the major adducted proteins in rat gastric carcinoma mucosal cell line and human colon cancer cell line, respectively. Furthermore, we found that heat-shock protein 27 was modified by methylglyoxal in ascending colon and rectum of patients with cancer. However, methylglyoxal-modified heat-shock protein 25/heat-shock protein 27 was not detected in non cancerous cell lines or in normal subject. Matrix-associated laser desorption/ionization mass spectrometry/mass spectrometry analysis of peptide fragments identified Arg-75, Arg-79, Arg-89, Arg-94, Arg-127, Arg-136, Arg-140, Arg-188, and Lys-123 as methylglyoxal modification sites in heat-shock protein 27 and in phosphorylated heat-shock protein 27. The transfer of methylglyoxal-modified heat-shock protein 27 into rat intestinal epithelial cell line RIE was even more effective in preventing apoptotic cell death than that of native control heat-shock protein 27. Furthermore, methylglyoxal modification of heat-shock protein 27 protected the cells against both the hydrogen peroxide- and cytochrome c-mediated caspase activation, and the hydrogen peroxide-induced production of intracellular reactive oxygen species. The levels of lactate converted from methylglyoxal were increased in carcinoma mucosal cell lines. Our results suggest that posttranslational modification of heat-shock protein 27 by methylglyoxal may have important implications for epithelial cell injury in gastrointestinal cancer.

  18. Hormonal modulation of the heat shock response: insights from fish with divergent cortisol stress responses

    DEFF Research Database (Denmark)

    LeBlanc, Sacha; Höglund, Erik; Gilmour, Kathleen M.;

    2012-01-01

    shock response, we capitalized on two lines of rainbow trout specifically bred for their high (HR) and low (LR) cortisol response to stress. We predicted that LR fish, with a low cortisol but high catecholamine response to stress, would induce higher levels of HSPs after acute heat stress than HR trout......Acute temperature stress in animals results in increases in heat shock proteins (HSPs) and stress hormones. There is evidence that stress hormones influence the magnitude of the heat shock response; however, their role is equivocal. To determine whether and how stress hormones may affect the heat....... We found that HR fish have significantly higher increases in both catecholamines and cortisol compared with LR fish, and LR fish had no appreciable stress hormone response to heat shock. This unexpected finding prevented further interpretation of the hormonal modulation of the heat shock response...

  19. A minimal titration modelization of the mammalian dynamical heat shock response

    CERN Document Server

    Aude, Sivéry; Thommen, Quentin

    2015-01-01

    Environmental stress, such as oxidative or heat stress, induces the activation of the Heat Shock Response (HSR) which leads to an increase in the heat shock proteins (HSPs) level. These HSPs act as molecular chaperones to maintain proteostasis. Even if the main heat shock response partners are well known, a detailed description of the dynamical properties of the HSR network is still missing. In this study, we derive a minimal mathematical model of cellular response to heat shock that reproduces available experimental data sets both on transcription factor activity and cell viability. This simplistic model highlights the key mechanistic processes that rule the HSR network and reveals (i) the titration of Heat Shock Factor 1 (HSF1) by chaperones as the guiding line of the network, (ii) that protein triage governs the fate of damaged proteins and (iii) three different temperature regimes describing normal, acute or chronic stress.

  20. Effect of short-term pre-hatch heat shock of incubating eggs on ...

    African Journals Online (AJOL)

    Effect of short-term pre-hatch heat shock of incubating eggs on subsequent. ... of thermal conditioning of broiler chickens during embryonic development on subsequent ... Keywords: Heat stress, incubation, parent age, live weight, mortality

  1. Magnetogasdynamic Cylindrical Shock Waves in a Rotating Nonideal Gas with Radiation Heat Flux

    Science.gov (United States)

    Vishwakarma, J. P.; Patel, Nanhey

    2015-03-01

    A similarity solution is presented for a cylindrical magnetogasdynamic shock wave in a rotating nonideal gas in the presence of a variable axial magnetic field in the case where the radiation heat flux is of importance. The initial angular velocity of the medium is assumed to vary as some power of the distance from the symmetry axis. The radiation heat flux is evaluated from the equation of motion without explicit use of the radiation transfer equations. It is shown that the gas nonidealness increases the shock strength but decreases the shock velocity. On the other hand, the presence of a magnetic field decreases the shock strength but increases the shock velocity. Moreover, the shock velocity increases with the ratio of specific heats. The total energy of the shock wave increases with time.

  2. Heat shock genes – integrating cell survival and death

    Indian Academy of Sciences (India)

    Richa Arya; Moushami Mallik; Subhash C Lakhotia

    2007-04-01

    Heat shock induced gene expression and other cellular responses help limit the damage caused by stress and thus facilitate cellular recovery. Cellular damage also triggers apoptotic cell death through several pathways. This paper briefly reviews interactions of the major heat shock proteins with components of the apoptotic pathways. Hsp90, which acts as a chaperone for unstable signal transducers to keep them poised for activation, interacts with RIP and Akt and promotes NF-B mediated inhibition of apoptosis; in addition it also blocks some steps in the apoptotic pathways. Hsp70 is mostly anti-apoptotic and acts at several levels like inhibition of translocation of Bax into mitochondria, release of cytochrome c from mitochondria, formation of apoptosome and inhibition of activation of initiator caspases. Hsp70 also modulates JNK, NF-B and Akt signaling pathways in the apoptotic cascade. In contrast, Hsp60 has both anti- and pro-apoptotic roles. Cytosolic Hsp60 prevents translocation of the pro-apoptotic protein Bax into mitochondria and thus promotes cell survival but it also promotes maturation of procaspase-3, essential for caspase mediated cell death. Our recent in vivo studies show that RNAi for the Hsp60D in Drosophila melanogaster prevents induced apoptosis. Hsp27 exerts its anti-apoptotic influence by inhibiting cytochrome c and TNF-mediated cell death. crystallin suppresses caspase-8 and cytochrome c mediated activation of caspase-3. Studies in our laboratory also reveal that absence or reduced levels of the developmentally active as well as stress induced non-coding hsr transcripts, which are known to sequester diverse hnRNPs and related nuclear RNA-binding proteins, block induced apoptosis in Drosophila. Modulation of the apoptotic pathways by Hsps reflects their roles as ``weak links” between various ``hubs” in cellular networks. On the other hand, non-coding RNAs, by virtue of their potential to bind with multiple proteins, can act as ``hubs” in

  3. Heat protective role and mechanism of heat shock protein Hpc60

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A cytosolic heat shock protein named Hpc60 has been purified by immunoaffinity chromatography from pea leaves and its function has been examined in vitro. Results show that Hpc60 may suppress the aggregation of luciferase (LUC), protect lactate dehydrogenase (LDH) and ascorbate peroxidase (APX) from thermal inactivation. It also shows that Mg2+, ATP and pH affect the protective function of Hpc60 in different manners.

  4. HSF transcription factor family, heat shock response, and protein intrinsic disorder.

    Science.gov (United States)

    Westerheide, Sandy D; Raynes, Rachel; Powell, Chase; Xue, Bin; Uversky, Vladimir N

    2012-02-01

    Intrinsically disordered proteins are highly abundant in all kingdoms of life, and several protein functional classes, such as transcription factors, transcriptional regulators, hub and scaffold proteins, signaling proteins, and chaperones are especially enriched in intrinsic disorder. One of the unique cellular reactions to protein damaging stress is the so-called heat shock response that results in the upregulation of heat shock proteins including molecular chaperones. This molecular protective mechanism is conserved from prokaryotes to eukaryotes and allows an organism to respond to various proteotoxic stressors, such as heat shock, oxidative stress, exposure to heavy metals, and drugs. The heat shock response- related proteins can be expressed during normal conditions (e.g., during the cell growth and development) or can be induced by various pathological conditions, such as infection, inflammation, and protein conformation diseases. The initiation of the heat shock response is manifested by the activation of the heat shock transcription factors HSF 1, part of a family of related HSF transcription factors. This review analyzes the abundance and functional roles of intrinsic disorder in various heat shock transcription factors and clearly shows that the heat shock response requires HSF flexibility to be more efficient. © 2012 Bentham Science Publishers

  5. Circulating Heat Shock Proteins in Women With a History of Recurrent Vulvovaginitis

    Directory of Open Access Journals (Sweden)

    P. C. Giraldo

    1999-01-01

    70-kDa heat shock proteins (hsp60 and hsp70, respectively in the circulation of women with or without a history of recurrent BV or candidal vaginitis and with or without a current lower genital tract infection. Heat shock protein expression is associated with a down-regulation of proinflammatory immune responses that would inhibit microbial infection.

  6. Acquired Thermotolerance and Heat Shock Proteins in Thermophiles from the Three Phylogenetic Domains

    DEFF Research Database (Denmark)

    Trent, Jonathan D.; Gabrielsen, Mette; Jensen, Bo;

    1994-01-01

    Thermophilic organisms from each of the three phylogenetic domains (Bacteria, Archaea, and Eucarya) acquired thermotolerance after heat shock. Bacillus caldolyticus grown at 60 degrees C and heat shocked at 69 degrees C for 10 min showed thermotolerance at 74 degrees C, Sulfolobus shibatae grown...

  7. HEAT SHOCK PROTEIN gp96 AND CANCER IMMUNOTHERAPY

    Institute of Scientific and Technical Information of China (English)

    岳培彬; 杨树德; 黄常志

    2002-01-01

    Heat shock protein gp96 is a highly conserved and monomorphic glycoprotein in the endoplasmic reticulum.It functions as molecular chaperone and can associate with a variety of antigenic peptides noncovalently in vivo and in vitro. Recent studies have indicated that gp96 molecules participate in major histocompatibility complex class I - restricted antigen presentation pathway. Immunization of mice with gp96 preparations isolated from cancer cells can elicit a cancer - specific protective T cell immune response that is recallable, which is a prerequisite for gp96 as a therapeutic vaccine against cancers. The immunogenicity of gp96 molecules has been attributed to the antigenic peptides associated with them. These phenomena provide a new pathway for cancer immunotherapy. The mechanism that the gp96 -peptide complex induces specific immune response and the explorations for gp96 - peptide complex as a therapeutic cancer vaccine are reviewed.

  8. Proteomic Analysis of Trypanosoma cruzi Epimastigotes Subjected to Heat Shock

    Directory of Open Access Journals (Sweden)

    Deyanira Pérez-Morales

    2012-01-01

    Full Text Available Trypanosoma cruzi is exposed to sudden temperature changes during its life cycle. Adaptation to these variations is crucial for parasite survival, reproduction, and transmission. Some of these conditions may change the pattern of genetic expression of proteins involved in homeostasis in the course of stress treatment. In the present study, the proteome of T. cruzi epimastigotes subjected to heat shock and epimastigotes grow normally was compared by two-dimensional gel electrophoresis followed by mass spectrometry for protein identification. Twenty-four spots differing in abundance were identified. Of the twenty-four changed spots, nineteen showed a greater intensity and five a lower intensity relative to the control. Several functional categories of the identified proteins were determined: metabolism, cell defense, hypothetical proteins, protein fate, protein synthesis, cellular transport, and cell cycle. Proteins involved in the interaction with the cellular environment were also identified, and the implications of these changes are discussed.

  9. Heat Shock Protein 70 in Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Rui-Chun Lu

    2014-01-01

    Full Text Available Alzheimer’s disease (AD is the most common neurodegenerative disease that caused dementia which has no effective treatment. Growing evidence has demonstrated that AD is a “protein misfolding disorder” that exhibits common features of misfolded, aggregation-prone proteins and selective cell loss in the mature nervous system. Heat shock protein 70 (HSP70 attracts extensive attention worldwide, because it plays a crucial role in preventing protein misfolding and inhibiting aggregation and represents a class of proteins potentially involved in AD pathogenesis. Numerous studies have indicated that HSP70 could suppress the progression of AD with in vitro and in vivo experiments. Thus, targeting HSP70 and the related compounds might represent a promising strategy for the treatment of AD.

  10. Heat Shock Protein 90 regulates encystation in Entamoeba

    Directory of Open Access Journals (Sweden)

    Meetali eSingh

    2015-10-01

    Full Text Available Enteric protozoan Entamoeba histolytica is a major cause of debilitating diarrheal infection worldwide with high morbidity and mortality. Even though the clinical burden of this parasite is very high, this infection is categorized as a neglected disease. Parasite is transmitted through feco-oral route and exhibit two distinct stages namely – trophozoites and cysts. Mechanism and regulation of encystation is not clearly understood. Previous studies have established the role of Heat shock protein 90 (Hsp90 in regulating stage transition in various protozoan parasites like Giardia, Plasmodium, Leishmania and Toxoplasma. Our study for the first time reports that Hsp90 plays a crucial role in life cycle of Entamoeba as well. We identify Hsp90 to be a negative regulator of encystation in Entamoeba. We also show that Hsp90 inhibition interferes with the process of phagocytosis in Entamoeba. Overall, we show that Hsp90 plays an important role in virulence and transmission of Entamoeba.

  11. Role of heat shock proteins in cell apoptosis

    Directory of Open Access Journals (Sweden)

    Arleta Kaźmierczuk

    2010-06-01

    Full Text Available Apoptosis is, apart from necrosis and autophagy, one of the possible cell death mechanisms eliminating needless, not normal or infected cells. This process ensures quantitative and qualitative cell control of organisms. Apoptosis is tightly regulated, it requires both activation of a large number of genes and energy input. Up-to-date two main apoptotic pathways have been recognized – external/receptor and internal, processed with the participation of mitochondria. Heat shock proteins HSPs, the molecules known from their chaperone activity and molecular conservatism, play essential functions in the course of apoptosis. Among that proteins family, i.e. HSP100, 90, 70, 60, 40 and small molecular (sHSP, there are agents mainly protective against programmed cell death. However, in some conditions some of these proteins may promote apoptosis. This review describes different key apoptotic proteins interacting with main members of HSP family and the consequence of these events for cell survival or apoptosis.

  12. The hexameric structures of human heat shock protein 90.

    Directory of Open Access Journals (Sweden)

    Cheng-Chung Lee

    Full Text Available BACKGROUND: The human 90-kDa heat shock protein (HSP90 functions as a dimeric molecular chaperone. HSP90 identified on the cell surface has been found to play a crucial role in cancer invasion and metastasis, and has become a validated anti-cancer target for drug development. It has been shown to self-assemble into oligomers upon heat shock or divalent cations treatment, but the functional role of the oligomeric states in the chaperone cycle is not fully understood. PRINCIPAL FINDINGS: Here we report the crystal structure of a truncated HSP90 that contains the middle segment and the carboxy-terminal domain, termed MC-HSP90. The structure reveals an architecture with triangular bipyramid geometry, in which the building block of the hexameric assembly is a dimer. In solution, MC-HSP90 exists in three major oligomer states, namely dimer, tetramer and hexamer, which were elucidated by size exclusion chromatography and analytical ultracentrifugation. The newly discovered HSP90 isoform HSP90N that lacks the N-terminal ATPase domain also exhibited similar oligomerization states as did MC-HSP90. CONCLUSIONS: While lacking the ATPase domain, both MC-HSP90 and HSP90N can self-assemble into a hexameric structure, spontaneously. The crystal structure of MC-HSP90 reveals that, in addition to the C-terminal dimerization domain, the residue W320 in the M domain plays a critical role in its oligomerization. This study not only demonstrates how the human MC-HSP90 forms a hexamer, but also justifies the similar formation of HSP90N by using 3D modeling analysis.

  13. Increased heat shock protein 70 expression in the pancreas of rats with endotoxic shock

    Institute of Scientific and Technical Information of China (English)

    Xue-Lian Wang; Ying Li; Jin-Song Kuang; Yue Zhao; Pei Liu

    2006-01-01

    AIM: To investigate the ultra-structural changes and heat shock protein 70 (HSP70) expression in the pancreas of rats with endotoxic shock and to detect their possible relationship.METHODS: A total of 33 Wistar rats were randomly divided into three groups: control group (given normal saline), small dose lipopolysaccharide (LPS) group (given LPS 5 mg/kg) and large dose LPS group (given LPS 10mg/kg). Pancreas was explanted to detect the ultrastructural changes by TEM and the HSP70 expression by immunohistochemistry and Western blot.RESULTS: Rats given small doses of LPS showed swelling and loss of mitochondrial cristae of acinar cells and increased number of autophagic vacuoles in the cytoplasm of acinar cells. Rats given large doses of LPS showed swelling, vacuolization, and obvious myeloid changes of mitochondrial cristae of acinar cells, increased number of autophagic vacuoles in the cytoplasm of acinar cells. HSP70 expression was increased compared to the control group (P<0.05).CONCLUSION: Small doses of LPS may induce stronger expression of HSP70, promote autophagocytosis and ameliorate ultra-structural injuries.

  14. Effects of Heat Stress on Yeast Heat Shock Factor-Promoter Binding In Vivo

    Institute of Scientific and Technical Information of China (English)

    Ning LI; Le-Min ZHANG; Ke-Qin ZHANG; Jing-Shi DENG; Ralf PR(A)NDL; Fritz SCH(O)FFL

    2006-01-01

    Heat shock factor-DNA interaction is critical for understanding the regulatory mechanisms of stress-induced gene expression in eukaryotes. In this study, we analyzed the in vivo binding of yeast heat shock factor (HSF) to the promoters of target genes ScSSA1, ScSSA4, HSP30 and HSP104, using chromatin immunoprecipitation. Previous work suggested that yeast HSF is constitutively bound to DNA at all temperatures. Expression of HSF target genes is regulated at the post-transcriptional level. However, our results indicated that HSF does not bind to the promoters of ScSSA4 and HSP30 at normal temperature (23 ℃). Binding to these promoters is rapidly induced by heat stress at 39 ℃. HSF binds to ScSSA1 and HSP104 promoters under non-stress conditions, but at a low level. Heat stress rapidly leads to a notable increase in the binding of HSF to these two genes. The kinetics of the level of HSF-promoter binding correlate well with the expression of target genes, suggesting that the expression of HSF target genes is at least partially the result of HSF-promoter binding stability and subsequent transcription stimulation.

  15. Global analysis of heat shock response in Desulfovibrio vulgaris Hildenborough.

    Energy Technology Data Exchange (ETDEWEB)

    Arkin, A. P. (Physical Biosciences Division, Berkeley, CA); Wall, J. D. (University of Missouri-Columbia, Columbia, MO); Hazen, T. C. (Physical Biosciences Division, Berkeley, CA); He, Z. (Oak Ridge National Laboratory, Oak Ridge, TN); Zhou, J. (Oak Ridge National Laboratory, Oak Ridge, TN); Huang, K. H. (Physical Biosciences Division, Berkeley, CA); Gaucher, Sara P.; He, Q. (Oak Ridge National Laboratory, Oak Ridge, TN); Hadi, Masood Z.; Chhabra, Swapnil R.; Alm, Eric J. (Physical Biosciences Division, Berkeley, CA); Singh, A. K.

    2005-08-01

    Desulfovibrio vulgaris Hildenborough belongs to a class of sulfate-reducing bacteria (SRB) and is found ubiquitously in nature. Given the importance of SRB-mediated reduction for bioremediation of metal ion contaminants, ongoing research on D. vulgaris has been in the direction of elucidating regulatory mechanisms for this organism under a variety of stress conditions. This work presents a global view of this organism's response to elevated growth temperature using whole-cell transcriptomics and proteomics tools. Transcriptional response (1.7-fold change or greater; Z {ge} 1.5) ranged from 1,135 genes at 15 min to 1,463 genes at 120 min for a temperature up-shift of 13 C from a growth temperature of 37 C for this organism and suggested both direct and indirect modes of heat sensing. Clusters of orthologous group categories that were significantly affected included posttranslational modifications; protein turnover and chaperones (up-regulated); energy production and conversion (down-regulated), nucleotide transport, metabolism (down-regulated), and translation; ribosomal structure; and biogenesis (down-regulated). Analysis of the genome sequence revealed the presence of features of both negative and positive regulation which included the CIRCE element and promoter sequences corresponding to the alternate sigma factors {sigma}{sup 32} and {sigma}{sup 54}. While mechanisms of heat shock control for some genes appeared to coincide with those established for Escherichia coli and Bacillus subtilis, the presence of unique control schemes for several other genes was also evident. Analysis of protein expression levels using differential in-gel electrophoresis suggested good agreement with transcriptional profiles of several heat shock proteins, including DnaK (DVU0811), HtpG (DVU2643), HtrA (DVU1468), and AhpC (DVU2247). The proteomics study also suggested the possibility of posttranslational modifications in the chaperones DnaK, AhpC, GroES (DVU1977), and GroEL (DVU

  16. Previous heat shock treatment inhibits Mayaro virus replication in human lung adenocarcinoma (A549) cells.

    Science.gov (United States)

    Virgilio, P L; Godinho-Netto, M C; Carvalho Mda, G

    1997-01-01

    Human lung adenocarcinoma cells (A549) were submitted to mild or severe heat shock (42 degrees C or 44 degrees C) for 1 h, while another group of cells was double-heat-shocked (submitted to 42 degrees C for 1 h, returned to 37 degrees C for 3 h, then exposed to 44 degrees C for 1 h). After each heat treatment, the cells were infected with Mayaro virus for 24 h and incubated at 37 degrees C. The results showed that the double-heat-shocked thermotolerant cells exhibited a 10(4)-fold virus titre inhibition, despite the recovery of protein synthesis and original morphology 24 h post-infection. In contrast, cells submitted to mild or severe heat shock exhibited weaker inhibition of Mayaro virus titre (10(2)-fold). The mildly heat-shocked cells also presented a full recovery in protein synthesis, which was not observed in severely heat-shocked cells. These results indicate that exposure of A549 cells to a mild or to a double heat shock treatment before Mayaro virus infection induces an antiviral state.

  17. The Transcriptional Heat Shock Response of Salmonella Typhimurium Shows Hysteresis and Heated Cells Show Increased Resistance to Heat and Acid Stress

    DEFF Research Database (Denmark)

    Pin, C.; Hansen, Trine; Munoz-Cuevas, M.

    2012-01-01

    of 120 up-regulated genes during the heat shock remained up-regulated 30 minutes after the temperature was set back to 25uC, while only 86 out of 293 down regulated genes remained down regulated 30 minutes after the heat shock ceased. Thus, the majority of the induced genes exhibited hysteresis, i...

  18. Tissue-type-specific heat-shock response and immunolocalization of class I low-molecular-weight heat-shock proteins in soybean

    Energy Technology Data Exchange (ETDEWEB)

    Tsung-Luo Jinn; Pi-Fang Linda Chang; Yih-Ming Chen [National Taiwan Univ. (China)] [and others

    1997-06-01

    A monospecific polyclonal antibody was used to study the tissue-type specificity and intracellular localization of class I low-molecular-weight (LMW) heat-shock proteins (HSPs) in soybean (Glycine max) under different heat-shock regimes. In etiolated soy-bean seedlings, the root meristematic regions contained the highest levels of LMW HSP. No tissue-type-specific expression of class I LMW HSP was detected using the tissue-printing method. In immunolocalization studies of seedlings treated with HS (40{degrees}C for 2 h) the class I LMW HSPs were found in the aggregated granular structures, which were distributed randomly in the cytoplasm and in the nucleus. When the heat shock was released, the granular structures disappeared and the class I LMW HSPs became distributed homogeneously in the cytoplasm. When the seedlings were then given a more severe heat shock following the initial 40{degrees}C {yields} 28{degrees}C treatment, a large proportion of the class I LMW HSPs that originally localized in the cytoplasm were translocated into the nucleus and nucleolus. Class I LMW HSPs may assist in the resolubilization of proteins denatured or aggregated by heat and may also participate in the restoration of organellar function after heat shock.

  19. Errors in macromolecular synthesis after stress : a study of the possible protective role of the small heat shock proteins

    NARCIS (Netherlands)

    Marin Vinader, L.

    2006-01-01

    The general goal of this thesis was to gain insight in what small heat shock proteins (sHsps) do with respect to macromolecular synthesis during a stressful situation in the cell. It is known that after a non-lethal heat shock, cells are better protected against a subsequent more severe heat shock,

  20. The pertinence of expression of heat shock proteins (HSPs) to the efficacy of cryopreservation in HELAs.

    Science.gov (United States)

    Wang, Peitao; Shu, Zhiquan; He, Liqun; Cui, Xiangdong; Wang, Yuzhen; Gao, Dayong

    2005-01-01

    HELAs (Hela cells, passed cells of human cervical carcinoma) were heat or cold treated (named heat or cold shock) and then resumed normal culture for 2, 4 or 8 hours respectively. The expressions of heat shock protein 70 (HSP70) and 90 (HSP90) of the HELAs were measured by Northern and Western blotting. HELAs after 4-hour culture were exposed to or cryopreserved with different concentration of dimethyl sulfoxide (Me2SO, 2.5%, 5%, 10%, 15% and 20% respectively, V/V). Meanwhile, the HELAs after different culture time (2, 4 and 6 hours of culture) were cryopreserved with 5% Me2SO. After exposure or cryopreservation, the number of live HELAs was counted and the survival rate was calculated. The results showed that heat shock increased the expression of HSP70 and HSP90 of HELAs, while cold shock decreased the expression of the two proteins. When the concentrations of Me2SO were 10%, 15% and 20%, the survival rates of HELAs after exposure to Me2SO or cryopreservation were much lower than those when the concentrations were small. The survival rates of the heat shocked HELAs were significantly higher than those of the cold shocked and control HELAs. After cryopreservation with 5% Me2SO, the survival rate of heat shocked HELAs group with 2 hours culture time was the lowest among all the groups of HELAs with different cultural time. From the results of this study, we conclude that the expressions of HSP70 and HSP90 in HELAs increased significantly after heat shock, while cold shock decreased the expressions of these two proteins. The over-expressions of HSPs in the heat shocked HELAs could protect the cells from both injury caused by potential toxicity of high concentrations of Me2SO and cryoinjury caused by the freeze-thawing/cryopreservation procedure.

  1. BH3-only protein BIM mediates heat shock-induced apoptosis.

    Science.gov (United States)

    Mahajan, Indra M; Chen, Miao-Der; Muro, Israel; Robertson, John D; Wright, Casey W; Bratton, Shawn B

    2014-01-01

    Acute heat shock can induce apoptosis through a canonical pathway involving the upstream activation of caspase-2, followed by BID cleavage and stimulation of the intrinsic pathway. Herein, we report that the BH3-only protein BIM, rather than BID, is essential to heat shock-induced cell death. We observed that BIM-deficient cells were highly resistant to heat shock, exhibiting short and long-term survival equivalent to Bax(-/-)Bak(-/-) cells and better than either Bid(-/-) or dominant-negative caspase-9-expressing cells. Only Bim(-/-) and Bax(-/-)Bak(-/-) cells exhibited resistance to mitochondrial outer membrane permeabilization and loss of mitochondrial inner membrane potential. Moreover, while dimerized caspase-2 failed to induce apoptosis in Bid(-/-) cells, it readily did so in Bim(-/-) cells, implying that caspase-2 kills exclusively through BID, not BIM. Finally, BIM reportedly associates with MCL-1 following heat shock, and Mcl-1(-/-) cells were indeed sensitized to heat shock-induced apoptosis. However, pharmacological inhibition of BCL-2 and BCL-X(L) with ABT-737 also sensitized cells to heat shock, most likely through liberation of BIM. Thus, BIM mediates heat shock-induced apoptosis through a BAX/BAK-dependent pathway that is antagonized by antiapoptotic BCL-2 family members.

  2. The Entamoeba histolytica methylated LINE-binding protein EhMLBP provides protection against heat shock.

    Science.gov (United States)

    Katz, Sophia; Kushnir, Oded; Tovy, Ayala; Siman Tov, Rama; Ankri, Serge

    2012-01-01

    Adaptation to environmental stress is a key process that allows the unicellular parasite Entamoeba histolytica to survive in its human host. We previously characterized EhMLBP as an essential protein for the growth and the virulence of the parasite. EhMLBP binds to methylated repetitive DNA, and is one of the core proteins of the parasite's epigenetic machinery. Here, we show that EhMLBP and heat shock proteins have common properties. EhMLBP is induced by heat shock and its expression is regulated by a heat shock element binding site that is located in its 5' non-coding region. Following heat shock, the perinuclear localization of EhMLBP in control trophozoites is replaced by an even distribution within the nucleus alongside with an enhanced recruitment of EhMLBP to the reverse transcriptase of a long interspersed nucleotide element (LINE) DNA. Constitutive overexpression of EhMLBP protects trophozoites against heat shock and reduces protein aggregation. This protective function is lost in trophozoites that overexpress a mutated form of EhMLBP which is devoid of its heat shock domain. To the best of our knowledge, this is the first report of a methyl DNA-binding protein that plays a protective role against heat shock.

  3. Exercise-induced ROS in heat shock proteins response.

    Science.gov (United States)

    Dimauro, Ivan; Mercatelli, Neri; Caporossi, Daniela

    2016-09-01

    Cells have evolved multiple and sophisticated stress response mechanisms aiming to prevent macromolecular (including proteins, lipids, and nucleic acids) damage and to maintain or re-establish cellular homeostasis. Heat shock proteins (HSPs) are among the most highly conserved, ubiquitous, and abundant proteins in all organisms. Originally discovered more than 50 years ago through heat shock stress, they display multiple, remarkable roles inside and outside cells under a variety of stresses, including also oxidative stress and radiation, recognizing unfolded or misfolded proteins and facilitating their restructuring. Exercise consists in a combination of physiological stresses, such as metabolic disturbances, changes in circulating levels of hormones, increased temperature, induction of mild to severe inflammatory state, increased production of reactive oxygen and nitrogen species (ROS and RNS). As a consequence, exercise is one of the main stimuli associated with a robust increase in different HSPs in several tissues, which appears to be also fundamental in facilitating the cellular remodeling processes related to the training regime. Among all factors involved in the exercise-related modulation of HSPs level, the ROS production in the contracting muscle or in other tissues represents one of the most attracting, but still under discussion, mechanism. Following exhaustive or damaging muscle exercise, major oxidative damage to proteins and lipids is likely involved in HSP expression, together with mechanically induced damage to muscle proteins and the inflammatory response occurring several days into the recovery period. Instead, the transient and reversible oxidation of proteins by physiological concentrations of ROS seems to be involved in the activation of stress response following non-damaging muscle exercise. This review aims to provide a critical update on the role of HSPs response in exercise-induced adaptation or damage in humans, focusing on experimental

  4. Heat-shock-induced cellular responses to temperature elevations occurring during orthopaedic cutting.

    Science.gov (United States)

    Dolan, E B; Haugh, M G; Tallon, D; Casey, C; McNamara, L M

    2012-12-07

    Severe heat-shock to bone cells caused during orthopaedic procedures can result in thermal damage, leading to cell death and initiating bone resorption. By contrast, mild heat-shock has been proposed to induce bone regeneration. In this study, bone cells are exposed to heat-shock for short durations occurring during surgical cutting. Cellular viability, necrosis and apoptosis are investigated immediately after heat-shock and following recovery of 12, 24 h and 4 days, in osteocyte-like MLO-Y4 and osteoblast-like MC3T3-E1 cells, using flow cytometry. The regeneration capacity of heat-shocked Balb/c mesenchymal stem cells (MSCs) and MC3T3-E1s has been investigated following 7 and 14 day's recovery, by quantifying proliferation, differentiation and mineralization. An immediate necrotic response to heat-shock was shown in cells exposed to elevated temperatures (45°C, 47°C and most severe at 60°C). A longer-term apoptotic response is induced in MLO-Y4s and, to a lesser extent, in MC3T3-E1s. Heat-shock-induced differentiation and mineralization by MSCs. These findings indicate that heat-shock is more likely to induce apoptosis in osteocytes than osteoblasts, which might reflect their role as sensors detecting and communicating damage within bone. Furthermore, it is shown for the first time that mild heat-shock (less than equal to 47°C) for durations occurring during surgical cutting can positively enhance osseointegration by osteoprogenitors.

  5. Heat shock response of the blue crab Portunus pelagicus:thermal stress and acclimation

    Institute of Scientific and Technical Information of China (English)

    Suhaila Qari

    2014-01-01

    Objective:To determine the effect of prior heat shock on the CTMax of differently acclimated Portunus pelagicus (P. pelagicus) as well as the time course of the changes in CTMax post heat shock. Methods: Crabs P. pelagicus were held in laboratory aquaria in tanks, which were supplied with filtered and aerated seawater. Crabs were acclimated at 20 °C, 25 °C, 30 °C and 35 °C for 3 weeks before their CTMax was determined. The CTMax was recorded for each crab as the median temperature during the 5 min period when a crab was not able to right itself, the average CTMax was calculated. The effect of heat shock on subsequent CTMax was measured. Crabs were heat shocked at temperature 1 °C lower than the CTMax for 20 min, followed by either 0.5 h, 1 h or 1.5 h recovery at 20 °C. The same procedure was repeated at other acclimation temperatures (25 °C, 30 °C and 35 °C). Results: Temperature acclimation of P. pelargicus from 20-35 °C progressively increased the CTMax. Acclimation at 35 °C the CTMax was 42.66 °C, whereas acclimation at 20 °C the CTMax was 39.8 °C. In P. pelagicus acclimated, at 20 °C the CTMax values after heat shock were significantly higher than crabs in control for 30 min, 1 h and 1.5 h after heat shock. In the 25 °C and 30 °C acclimated crabs, the CTMax values after heat shock were significantly higher than control only in 30 min and 1 h after heat shock. No significant differences in 35 °C acclimated crabs between control and heat shocked crabs were found after recovery for 30 min, 1 h, or 1.5 h. Conclusions: Heat shock caused significant rises in the CTMax, however, this increase was progressively reduced with longer recovery times at the acclimation temperature. For 20 °C acclimated crabs, the increased CTMax was still evident after 90 min, but for 25 °C and 30 °C crabs, the response was over after 90 min. Heat shock of 35 °C crabs was problematical, the CTMax gave no increased thermotolerance. It must be concluded that the

  6. Heat Shock Induction of Manganese Peroxidase Gene Transcription in Phanerochaete chrysosporium

    OpenAIRE

    Brown, Julie A.; Li, Dan; Alic, Margaret; Gold, Michael H.

    1993-01-01

    The expression of manganese peroxidase (MnP) in nitrogen-limited cultures of Phanerochaete chrysosporium is regulated by heat shock at the level of gene transcription. Nitrogen limitation and manganous ion [Mn(II)] previously have been shown to regulate mnp gene transcription. Northern (RNA) blot analysis demonstrates that 45°C heat shock results in the accumulation of mnp mRNA, even in cells grown in the absence of Mn. Heat shock induces mnp gene transcription in 4- or 5-day-old cells, and m...

  7. Role of TRP channels in the induction of heat shock proteins (Hsps) by heating skin.

    Science.gov (United States)

    Hsu, Wen-Li; Yoshioka, Tohru

    2015-01-01

    Transient receptor potential (TRP) channels in skin are crucial for achieving temperature sensitivity to maintain internal temperature balance and thermal homeostasis, as well as to protect skin cells from environmental stresses such as infrared (IR) or near-infrared (NIR) radiation via heat shock protein (Hsp) production. However, the mechanisms by which IR and NIR activate TRP channels and produce Hsps intracellularly have been independently reported. In this review, we discuss the relationship between TRP channel activation and Hsp production, and introduce the roles of several skin TRP channels in the regulation of HSP production by IR and NIR exposure.

  8. Changes in the transcriptome of morula-stage bovine embryos caused by heat shock: relationship to developmental acquisition of thermotolerance

    Directory of Open Access Journals (Sweden)

    Sakatani Miki

    2013-01-01

    Full Text Available Abstract Background While initially sensitive to heat shock, the bovine embryo gains thermal resistance as it progresses through development so that physiological heat shock has little effect on development to the blastocyst stage by Day 5 after insemination. Here, experiments using 3’ tag digital gene expression (3’DGE and real-time PCR were conducted to determine changes in the transcriptome of morula-stage bovine embryos in response to heat shock (40 degrees C for 8 h that could be associated with thermotolerance. Results Using 3’DGE, expression of 173 genes were modified by heat shock, with 94 genes upregulated by heat shock and 79 genes downregulated by heat shock. A total of 38 differentially-regulated genes were associated with the ubiquitin protein, UBC. Heat shock increased expression of one heat shock protein gene, HSPB11, and one heat shock protein binding protein, HSPBP1, tended to increase expression of HSPA1A and HSPB1, but did not affect expression of 64 other genes encoding heat shock proteins, heat shock transcription factors or proteins interacting with heat shock proteins. Moreover, heat shock increased expression of five genes associated with oxidative stress (AKR7A2, CBR1, GGH, GSTA4, and MAP2K5, decreased expression of HIF3A, but did not affect expression of 42 other genes related to free radical metabolism. Heat shock also had little effect on genes involved in embryonic development. Effects of heat shock for 2, 4 and 8 h on selected heat shock protein and antioxidant genes were also evaluated by real-time PCR. Heat shock increased steady-state amounts of mRNA for HSPA1A (PHSP90AA1 (PSOD1 or CAT. Conclusions Changes in the transcriptome of the heat-shocked bovine morula indicate that the embryo is largely resistant to effects of heat shock. As a result, transcription of genes involved in thermal protection is muted and there is little disruption of gene networks involved in embryonic development. It is likely that

  9. Influence of selenium on heat shock protein 70 expression in heat stressed turkey embryos (Meleagris gallopavo).

    Science.gov (United States)

    Rivera, Rafael E; Christensen, V L; Edens, F W; Wineland, M J

    2005-12-01

    Heat shock protein 70 (hsp70) family of proteins, which functions as molecular chaperones, has been associated with tolerance to stressors in avian species. Selenium (Se) is an essential trace mineral incorporated into the seleno-enzymes such as glutathione peroxidase (GSHpx). GSHpx reduces oxidized glutathione (GSSG) to reduced glutathione (GSH) in the GSH/GSSG antioxidant system and protects cells from oxidative damage. This study was conducted to examine if the relationship between dietary supplementation of selenium to turkey (Meleagris gallopavo) hens and the embryonic expression of hsp70 and GSHpx activity in heat stressed embryos. Livers of embryos developing in eggs from turkey hens fed diets with or without supplemental Se were analyzed for hsp70 concentration and GSHpx activity before and after recovery from a heating episode. Before heat stress, hsp70 concentrations were equivalent in each treatment, but GSHpx activity was maximized in the SE treatment group. After recovery from the heating episode, hsp70 concentrations were significantly higher (P<0.05) in the non-Se-supplemented groups, but in the Se-supplemented groups the hsp70 concentrations were not different from pre-stress concentrations. In the pre-stress Se-supplemented group, liver GSHpx activity was significantly higher than GSHpx activity in the non-Se-supplemented embryo livers, and in the livers from embryos recovering from heat stress, GSHpx activity in the non-Se-supplemented group was lower than the pre-stress activity and significantly lower than the GSHpx activity in liver from Se-supplemented embryos recovering from heat distress. Se supplementation to the dams resulted in a significant increase in their embryos and that condition would facilitate a decreased incidence of oxidative damage to cells. A more reduced redox status in embryos from Se-supplemented dams decreased the need for cellular protection attributed to stress induced hsp70 and presumably allows heat distressed embryos

  10. The role of small heat shock proteins in parasites.

    Science.gov (United States)

    Pérez-Morales, Deyanira; Espinoza, Bertha

    2015-09-01

    The natural life cycle of many protozoan and helminth parasites involves exposure to several hostile environmental conditions. Under these circumstances, the parasites arouse a cellular stress response that involves the expression of heat shock proteins (HSPs). Small HSPs (sHSPs) constitute one of the main families of HSPs. The sHSPs are very divergent at the sequence level, but their secondary and tertiary structures are conserved and some of its members are related to α-crystallin from vertebrates. They are involved in a variety of cellular processes. As other HSPs, the sHSPs act as molecular chaperones; however, they have shown other activities apparently not related to chaperone action. In this review, the diverse activities of sHSPs in the major genera of protozoan and helminth parasites are described. These include stress response, development, and immune response, among others. In addition, an analysis comparing the sequences of sHSPs from some parasites using a distance analysis is presented. Because many parasites face hostile conditions through its life cycles the study of HSPs, including sHSPs, is fundamental.

  11. Circulating Heat Shock Protein 70 in Health, Aging and Disease

    Directory of Open Access Journals (Sweden)

    Demanet Christian

    2011-03-01

    Full Text Available Abstract Background Heat shock proteins (Hsp are ubiquitously synthesised in virtually all species and it is hypothesised that they might have beneficial health effects. Recent studies have identified circulating Hsp as an important mediator in inflammation - the effects of low-grade inflammation in the aging process are overwhelming. While much is known about intracellular Hsp70, scant data exist on circulating Hsp70 in the aging context. Therefore, the objectives of this study were to investigate the effect of age and disease on circulating Hsp70 and, in particular, to evaluate the association between circulating Hsp70 and inflammatory parameters. Results Serum Hsp70, Interleukin (IL -10, IL-6 and Tumor Necrosis Factor (TNF alpha concentrations were determined in 90 hospitalised geriatric patients (aged 83 ± 6 years and in 200 community-dwelling control subjects (100 elderly, aged 74 ± 5 years, and 100 young, aged 23 ± 3 years. In the community-dwelling elderly, serum Hsp70 and IL-10 concentrations were significantly lower and IL-6 was significantly higher when compared to healthy young control subjects. Elderly patients presenting inflammation (CRP serum levels ≥5 mg/L showed significantly (p = 0.007 higher Hsp70 values; and Hsp70 correlated positively (p Conclusions The present data provide new evidence that serum concentration of Hsp70 decreases with age in a normal population. Our study also shows that higher levels of Hsp70 are associated with inflammation and frailty in elderly patients.

  12. Heat Shock Proteins: Stimulators of Innate and Acquired Immunity

    Directory of Open Access Journals (Sweden)

    Camilo A. Colaco

    2013-01-01

    Full Text Available Adjuvants were reintroduced into modern immunology as the dirty little secret of immunologists by Janeway and thus began the molecular definition of innate immunity. It is now clear that the binding of pathogen-associated molecular patterns (PAMPs by pattern recognition receptors (PRRs on antigen presenting cells (APCs activates the innate immune response and provides the host with a rapid mechanism for detecting infection by pathogens and initiates adaptive immunity. Ironically, in addition to advancing the basic science of immunology, Janeway’s revelation on induction of the adaptive system has also spurred an era of rational vaccine design that exploits PRRs. Thus, defined PAMPs that bind to known PRRs are being specifically coupled to antigens to improve their immunogenicity. However, while PAMPs efficiently activate the innate immune response, they do not mediate the capture of antigen that is required to elicit the specific responses of the acquired immune system. Heat shock proteins (HSPs are molecular chaperones that are found complexed to client polypeptides and have been studied as potential cancer vaccines. In addition to binding PRRs and activating the innate immune response, HSPs have been shown to both induce the maturation of APCs and provide chaperoned polypeptides for specific triggering of the acquired immune response.

  13. The Immunosuppressive Activity of Heat Shock Protein 70

    Directory of Open Access Journals (Sweden)

    Pawel Stocki

    2012-01-01

    Full Text Available Heat shock protein 70 (HSP70 has previously been described as a potent antitumour vaccine. The mechanism relied on the ability of tumour derived HSP70 to associate with antigenic peptides, which, when cross presented, elicited a T cell mediated antitumour response. Subsequently, HSP70 was incorrectly described as a potent adjuvant of innate immunity, and although mistakes in the experimental approaches were exposed and associated with endotoxin contamination in the recombinant HSP70 specimen, questions still remain regarding this matter. Here we review only publications that have cautiously addressed the endotoxin contamination problem in HSP70 in order to reveal the real immunological function of the protein. Accordingly, “endotoxin free” HSP70 stimulates macrophages and delivers antigenic peptides to APCs, which effectively prime T cells mediating an antitumour reaction. Conversely, HSP70 has potent anti-inflammatory functions as follows: regulating T cell responses, reducing stimulatory capacity of DCs, and inducing development of immunosuppressive regulatory T cells. These activities were further associated with the immune evasive mechanism of tumours and implicated in the modulation of immune reactivity in autoimmune diseases and transplant-related clinical conditions. Consequently, the role of HSP70 in immune regulation is newly emerging and contrary to what was previously anticipated.

  14. Heat-shock protein 90 in Candida albicans

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Researches on Candidal heat-shock protein 90 (HSP90) in recent years are summarized.Candida albicans is a commensal pathogen in human and animals.In immunocompromised individuals it behaves as an opportunist pathogen,giving rise to superficial or systemic infections.Systemic candidosis is a common cause of death among immunocompromised and debilitated patients,in which the mortality is as high as 70%.HSP90 is now recognized as an immunodominant antigen in C.albicans and plays a key role in systemic candidosis as a molecular chaperone.The 47-ku peptide is the breakdown product of HSP90.Patients who has recovered from systemic candidosis produce high titre of antibodies to 47-ku antigen,whereas the fatal cases have little antibody or falling titres.The three commonest epitopes of candidal HSP90 have been mapped,epitopes C,B and H.Epitopes C and H are immunogenic.The antibody probes of both epitopes may be developed into a new serological test agents for systemic candidosis due to rather high specificity and sensitivity.The recent results establish HSP90 as an ATP-dependent chaperone that is involved in the folding of cell regulatory proteins and in the refolding of stress-denatured polypeptides.Some researches on fungal HSP90 and the treatment of patients with candidosis are reviewed as well.

  15. Heat-shock protein expression in canine corneal wound healing.

    Science.gov (United States)

    Peterson, Cornelia W M; Carter, Renee T; Bentley, Ellison; Murphy, Christopher J; Chandler, Heather L

    2016-05-01

    Heat-shock proteins, particularly the 70-kDa member (Hsp70), have been implicated in facilitating wound healing in multiple tissues. Expression and localization of three HSPs were assessed in normal and wounded canine corneas to elucidate a role in epithelial healing. Paraffin-embedded normal corneas, acute and repeatedly abraded corneas, and keratectomies of spontaneous chronic corneal epithelial defects (SCCEDs) were subjected to routine immunohistochemistry for Hsp27, 47, and 70 expression. Ex vivo corneal defects were created and treated with anti-HSPs or IgG controls, and wound healing was monitored. Primary cultures of canine corneal stromal fibroblasts and corneal epithelial cells were treated with exogenous Hsp70, and an artificial wound was created in vitro to monitor restoration of the monolayer. Normal canine corneas exhibited constitutive expression of all HSPs evaluated. Inducible expression was demonstrated in acutely wounded tissues, and expression in the chronically abraded corneas was relocalized. All HSP expression was below the limits of detection in the epithelium of SCCED samples. Inhibition of HSPs in culture resulted in delayed wound healing when compared to controls. Hsp70-treated fibroblasts demonstrated significantly (P healing response, and suppressed expression may contribute to the pathophysiology of nonhealing defects. © 2015 American College of Veterinary Ophthalmologists.

  16. The Involvement of Heat Shock Proteins in Murine Liver Regeneration

    Institute of Scientific and Technical Information of China (English)

    Qing Shi; Zhongjun Dong; Haiming Wei

    2007-01-01

    Partial hepatectomy (PHx) in mammals is a very common experimental model to investigate the process of liver regeneration. The surgery itself could give birth to a series of stresses, such as the temporary raise of body temperature and the ischaemia-reperfusion injury. Heat shock proteins (HSPs) were a family of stress-inducible proteins involved in maintaining cell homeostasis and regulating the immune system. In our study, we intended to investigate the expression and role of HSPs in liver regeneration. Using RT-PCR and Western blotting, we determined the expression in regenerating liver of HSP27, HSP60, HSP70 and HSP90 in mRNA level and protein level, respectively, with mice treated with sham operation as controls. We also used quercertin as an inhibitior of HSPs to explore their effects on liver regeneration. We found that hepatic expression of HSPs increased at the early phase of liver regeneration and declined to the constitutively low level later. Moreover, quercetin pretreatment delayed the progress of liver regeneration in mice via inhibition of HSPs. The results indicated that HSPs played an important role in liver regeneration.

  17. Increased heat shock protein expression after stress in Japanese quail.

    Science.gov (United States)

    Hoekstra, K A; Iwama, G K; Nichols, C R; Godin, D V; Cheng, K M

    1998-12-01

    Heat shock proteins (HSPs) have been shown to provide information on the biological impact of environmental stress to organisms, yet none have investigated the HSP response to stress in birds. Japanese quail were exposed to seven different stressors (mild restraint, loud noise, inescapable irritation, cold temperature, isolation in darkness, and two stressful social situations) and expression of HSP30, 60, 70, and 90 in heart, liver, lung, kidney and gonads was examined. Tonic Immobility (TI) tests were also conducted to assess whether the stressors increased fear response. Increased expression of HSP70 was found in the myocardial tissue of birds exposed to loud noise, inescapable irritation, cold temperature, and isolation in darkness. Increased expression of other HSPs was not apparent in the heart or any of the other all tissues examined. Longer TI was observed only in birds exposed to the noise stress. Evidence is presented that a fairly wide range of stressors caused increased expression of HSP70 in the Japanese quail myocardial tissue and that HSPs may provide useful biomarkers for the study of environmental stress in birds.

  18. The pleiotropic activity of heat-shock proteins

    Directory of Open Access Journals (Sweden)

    Arleta Kaźmierczuk

    2009-10-01

    Full Text Available Stress or heat-shock proteins (HSPs are highly conserved proteins present in cells of both prokaryotes and eukaryotes, providing them with protection from cellular and environmental stress factors. Based on molecular-weight, HSPs can be divided into the large (HSP100: 100–110 kDa and HSP90: 75–96 kDa, intermediate (HSP70: 66–78 kDa, HSP60, and HSP40, and small (sHSP: 8.5–40 kDa subfamilies. These proteins play an essential role as molecular chaperones/co-chaperones by assisting the correct folding of nascent and stress-accumulated protein-substrate assembly, preventing the aggregation of these proteins, as well as transport across membranes and the degradation of other proteins. Members of HSP family display dual activity depending on their intra- or extracellular distribution. Intracellular HSPs mainly play a protective role. Extracellular or membrane-bound HSPs mediate immunological functions. Among the functions of HSPs is their participation in cell signaling. This review deals with the structure and properties of the main members of the HSPs and their role in a large number of cellular/extracellular processes.

  19. Heat shock proteins: a therapeutic target worth to consider

    Science.gov (United States)

    Dubey, Amita; Prajapati, K. S.; Swamy, Madhu; Pachauri, V.

    2015-01-01

    Heat shock proteins (HSPs) are the molecular chaperones, that are not only expressed during the normal growth process of cell cycle consecutively, but also get induced in cells during various stress conditions produced by cellular insult, environmental changes, temperature, infections, tumors etc. According to their molecular weight and functions, HSPs are divided into five major families. HSP90, HSP70, HSP60 and HSP100 are the most studied members of the family. Experimental studies have proved that overexpression and/or inhibition of HSPs play an important role in maintaining the tolerance and cell viability under above-described stress conditions. HSP90 is found to be a promising the candidate for the diagnosis, prognosis and treatment of cancer. Similarly, HSP70, HSP60 and small HSPs experimentally and clinically have potential for the treatment of neurodegenerative disease, ischemia, cell death, autoimmunity, graft rejection, etc. In a way, exploring, the cytoprotective and immunoregulatory role of HSPs can open a new avenue for the drug discovery and treatment of critical diseases. PMID:27046995

  20. Extracellular heat shock proteins: a new location, a new function.

    Science.gov (United States)

    De Maio, Antonio; Vazquez, Daniel

    2013-10-01

    The expression of heat shock proteins (HSPs) is a basic and well-conserved cellular response to an array of stresses. These proteins are involved in the repair of cellular damage induced by the stress, which is necessary for the salutary resolution from the insult. Moreover, they confer protection from subsequent insults, which has been coined stress tolerance. Because these proteins are expressed in subcellular compartments, it was thought that their function during stress conditions was circumscribed to the intracellular environment. However, it is now well established that HSPs can also be present outside cells where they appear to display a function different than the well-understood chaperone role. Extracellular HSPs act as alert stress signals priming other cells, particularly of the immune system, to avoid the propagation of the insult and favor resolution. Because the majority of HSPs do not possess a secretory peptide signal, they are likely to be exported by a nonclassic secretory pathway. Different mechanisms have been proposed to explain the export of HSPs, including translocation across the plasma membrane and release associated with lipid vesicles, as well as the passive release after cell death by necrosis. Extracellular HSPs appear in various flavors, including membrane-bound and membrane-free forms. All of these variants of extracellular HSPs suggest that their interactions with cells may be quite diverse, both in target cell types and the activation signaling pathways. This review addresses some of our current knowledge about the release and relevance of extracellular HSPs.

  1. Small Heat Shock Proteins and Distal Hereditary Neuropathies.

    Science.gov (United States)

    Nefedova, V V; Muranova, L K; Sudnitsyna, M V; Ryzhavskaya, A S; Gusev, N B

    2015-12-01

    Classification of small heat shock proteins (sHsp) is presented and processes regulated by sHsp are described. Symptoms of hereditary distal neuropathy are described and the genes whose mutations are associated with development of this congenital disease are listed. The literature data and our own results concerning physicochemical properties of HspB1 mutants associated with Charcot-Marie-Tooth disease are analyzed. Mutations of HspB1, associated with hereditary motor neuron disease, can be accompanied by change of the size of HspB1 oligomers, by decreased stability under unfavorable conditions, by changes in the interaction with protein partners, and as a rule by decrease of chaperone-like activity. The largest part of these mutations is accompanied by change of oligomer stability (that can be either increased or decreased) or by change of intermonomer interaction inside an oligomer. Data on point mutation of HspB3 associated with axonal neuropathy are presented. Data concerning point mutations of Lys141 of HspB8 and those associated with hereditary neuropathy and different forms of Charcot-Marie-Tooth disease are analyzed. It is supposed that point mutations of sHsp associated with distal neuropathies lead either to loss of function (for instance, decrease of chaperone-like activity) or to gain of harmful functions (for instance, increase of interaction with certain protein partners).

  2. Destabilization and recovery of a yeast prion after mild heat shock.

    Science.gov (United States)

    Newnam, Gary P; Birchmore, Jennifer L; Chernoff, Yury O

    2011-05-06

    Yeast prion [PSI(+)] is a self-perpetuating amyloid of the translational termination factor Sup35. Although [PSI(+)] propagation is modulated by heat shock proteins (Hsps), high temperature was previously reported to have little or no effect on [PSI(+)]. Our results show that short-term exposure of exponentially growing yeast culture to mild heat shock, followed by immediate resumption of growth, leads to [PSI(+)] destabilization, sometimes persisting for several cell divisions after heat shock. Prion loss occurring in the first division after heat shock is preferentially detected in a daughter cell, indicating the impairment of prion segregation that results in asymmetric prion distribution between a mother cell and a bud. Longer heat shock or prolonged incubation in the absence of nutrients after heat shock led to [PSI(+)] recovery. Both prion destabilization and recovery during heat shock depend on protein synthesis. Maximal prion destabilization coincides with maximal imbalance between Hsp104 and other Hsps such as Hsp70-Ssa. Deletions of individual SSA genes increase prion destabilization and/or counteract recovery. The dynamics of prion aggregation during destabilization and recovery are consistent with the notion that efficient prion fragmentation and segregation require a proper balance between Hsp104 and other (e.g., Hsp70-Ssa) chaperones. In contrast to heat shock, [PSI(+)] destabilization by osmotic stressors does not always depend on cell proliferation and/or protein synthesis, indicating that different stresses may impact the prion via different mechanisms. Our data demonstrate that heat stress causes asymmetric prion distribution in a cell division and confirm that the effects of Hsps on prions are physiologically relevant.

  3. Mathematical modeling of heat shock protein synthesis in response to temperature change.

    Science.gov (United States)

    Szymańska, Zuzanna; Zylicz, Maciej

    2009-08-07

    One of the most important questions in cell biology is how cells cope with rapid changes in their environment. The range of common molecular responses includes a dramatic change in the pattern of gene expression and the elevated synthesis of so-called heat shock (or stress) proteins (HSPs). Induction of HSPs increases cell survival under stress conditions [Morimoto, R.I., 1993. Cells in stress: transcriptional activation of heat shock genes. Science 259, 1409-1410]. In this paper we propose a mathematical model of heat shock protein synthesis induced by an external temperature stimulus. Our model consists of a system of nine nonlinear ordinary differential equations describing the temporal evolution of the key variables involved in the regulation of HSP synthesis. Computational simulations of our model are carried out for different external temperature stimuli. We compare our model predictions with experimental data for three different cases-one corresponding to heat shock, the second corresponding to slow heating conditions and the third corresponding to a short heat shock (lasting about 40 min). We also present our model predictions for heat shocks carried out up to different final temperatures and finally we present a new hypothesis concerning the molecular response to stress that explains some phenomena observed in experiments.

  4. Heat shock suppresses mating and sperm transfer in the rice leaf folder Cnaphalocrocis medinalis.

    Science.gov (United States)

    Liao, H J; Qian, Q; Liu, X D

    2014-06-01

    Temperature is a key environmental factor in determining the population size of Cnaphalocrocis medinalis in summer. High temperatures inhibit survival, development and fecundity of this insect. However, biological responses of female and male adults to heat shock, and physiological mechanism of high temperature suppressing population development are still ambiguous. We experimentally tested the impact of heat shock (5 h day-1) on biological traits, spermatogenesis and sperm transfer of adults of C. medinalis. The result showed that heat exposure to 39 and 40 °C for 5 h reduced longevity and copulation frequency of adults, and hatchability of eggs. Immediate survival rate of males was lower than that of females after 3 days of exposure to 41 °C. The oviposition period, copulation frequency, fecundity of adults and hatchability of eggs were significantly lower when male adults were exposed to 40 or 41 °C for 3 days. Heat shock decreased frequency and success rate of mating when males were exposed, and it also resulted in postponement of mating behaviour and prolongation of mating duration as both the female and male adults were exposed. Heat shock did not affect spermatogenesis, but significantly inhibited sperms maturation. Moreover, males could not ejaculate sperm into females during copulation when these male moths received heat shock. Heat shock remarkably suppressed mating behaviour and sperm transfer, which led to a dramatic decline of rice leaf folder populations.

  5. Analysis of heat shock gene expression in Lactococcus lactis MG1363

    DEFF Research Database (Denmark)

    Arnau, José; Sørensen, Kim; Appel, Karen Fuglede

    1996-01-01

    The induction of the heat shock response in Lactococcus lactis subsp. cremoris strain MG1363 was analysed at the RNA level using a novel RNA isolation procedure to prevent degradation. Cloning of the dnaJ and groEL homologous was carried out. Nothern blot analysis showed a similar induction pattern......, although maximum induction was observed earlier for orf1 and grpE. Novel transcript sizes were detected in heat-shocked cells. The induction kinetics observed for ftsH suggested a different regulation for this gene. Experimental evidence for a prenounced transcriptional regulation being involved...... in the heat shock response in L. lactis MG1363 is presented. A gene located downstream of the dnaK operon in strain MG1363, named orf4, was shown not to be regulated by heat shock....

  6. 壽Activation of the mitogen-activated protein kinase pathways by heat shock

    OpenAIRE

    Dorion, Sonia; Landry, Jacques

    2002-01-01

    In addition to inducing new transcriptional activities that lead within a few hours to the accumulation of heat shock proteins (Hsps), heat shock activates within minutes the major signaling transduction pathways involving mitogen-activated protein kinases, extracellular signal–regulated kinase, stress-activated protein kinase 1 (SAPK1)–c-Jun N-terminal kinase, and SAPK2-p38. These kinases are involved in both survival and death pathways in response to other stresses and may, therefore, contr...

  7. Phosphoproteome dynamics reveal heat-shock protein complexes specific to the Leishmania donovani infectious stage

    OpenAIRE

    Morales, M. A.; R. WATANABE; Dacher, M.; Chafey, P.; Osorio y Fortea, J.; Scott, D A; Beverley, S. M.; van Ommen, G.; CLOS, J.; Hem, S.; Lenormand, P.; Rousselle, J.-C.; Namane, A.; Spath, G. F.

    2010-01-01

    Leishmania is exposed to a sudden increase in environmental temperature during the infectious cycle that triggers stage differentiation and adapts the parasite phenotype to intracellular survival in the mammalian host. The absence of classical promoter-dependent mechanisms of gene regulation and constitutive expression of most of the heat-shock proteins (HSPs) in these human pathogens raise important unresolved questions as to regulation of the heat-shock response and stage-specific functions...

  8. The effects of drying following heat shock exposure of the desert moss Syntrichia caninervis

    Energy Technology Data Exchange (ETDEWEB)

    Xu Shujun; Liu Chunjiang [School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240 (China); Jiang Pingan [College of Pratacultural and Environmental Science, Xinjiang Agricultural University, Urumqi 830052 (China); Cai Weimin [School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Wang Yan [School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China)], E-mail: xusj@mail.sjtu.edu.cn

    2009-03-15

    Desert mosses are components of biological soil crusts (BSCs) and their ecological functions make assessment and protection of these mosses a high-ranking management priority in desert regions. Drying is thought to be useful for desert mosses surviving heat shock. In this study, we investigated the role of drying by monitoring the responses of physiological characters and asexual reproduction in the typical desert moss Syntrichia caninervis. Heat significantly decreased chlorophyll content and weakened rapid recovery of photochemical activity, and increased carotenoid content and membrane permeability. Lethal temperatures significantly destroyed shoot regeneration potential. In comparison with heat alone, drying significantly increased protonema emergence time and depressed protonema emergence area. Drying combined with heat accelerated water loss, followed by a decrease of photosynthetic activity. Drying had different influences on membrane permeability at different temperatures. When moss leaves were subjected to a combined stress of drying and heat shock, photosynthesis was maintained mainly due to the effects of drying on physiological activity although the cellular morphological integrity was affected. Drying caused opposing effects on moss physiological and reproductive characteristics. On the one hand, drying caused a positive synergistic effect with heat shock when the temperature was below 40 deg. C. On the other hand, drying showed antagonism with heat shock when the moss was subjected to temperatures higher than 40 deg. C. These findings may help in understanding the survival mechanism of dessert mosses under heat shock stress which will be helpful for the artificial reconstruction of BSCs.

  9. Impact of Heat-Shock Treatment on Yellowing of Pak Choy Leaves

    Institute of Scientific and Technical Information of China (English)

    WANG Xiang-yang; SHEN Lian-qing; YUAN Hai-na

    2004-01-01

    The physiological mechanism of maintaining the green colour of pak choy leaves (Brassica rapa var chinensis) with heat-shock treatment was studied. Chlorophyll in the outer leaves of pak choy degraded rapidly during storage at ambient temperature (20 ± 2℃), a slight yellow appeared. Heat-shock treatment (46- 50℃) had a mild effect on maintaining the green colour of outer leaves. Normal chlorophyll degradation was associated with a binding of chlorophyll with chlorophyll-binding-protein preceding chlorophyll breakdown.Heat-shock treatment was found to reduce the binding-capacity between chlorophyllbinding-protein and chlorophyll. In the chlorophyll degradation pathway, pheide dioxygenase was synthesized during leaf senescence which was considered to be a key enzyme in chlorophyll degradation. Activity of this enzyme was reduced following heat-shock treatment, which might explain the observed reduction in chlorophyll breakdown. Two groups of heat-shock proteins were detected in treated leaves, the first group containing proteins from 54KDa to 74 Kda, and the second group contained proteins from 15 KDa to 29KDa. Heat-shock treatment was also found to retard the decline of glucose and fructose (the main energy substrates) of outer leaves.

  10. Molecular Dynamics Simulations of Shocks Including Electronic Heat Conduction and Electron-Phonon Coupling

    Science.gov (United States)

    Ivanov, Dmitriy S.; Zhigilei, Leonid V.; Bringa, Eduardo M.; De Koning, Maurice; Remington, Bruce A.; Caturla, Maria Jose; Pollaine, Stephen M.

    2004-07-01

    Shocks are often simulated using the classical molecular dynamics (MD) method in which the electrons are not included explicitly and the interatomic interaction is described by an effective potential. As a result, the fast electronic heat conduction in metals and the coupling between the lattice vibrations and the electronic degrees of freedom can not be represented. Under conditions of steep temperature gradients that can form near the shock front, however, the electronic heat conduction can play an important part in redistribution of the thermal energy in the shocked target. We present the first atomistic simulation of a shock propagation including the electronic heat conduction and electron-phonon coupling. The computational model is based on the two-temperature model (TTM) that describes the time evolution of the lattice and electron temperatures by two coupled non-linear differential equations. In the combined TTM-MD method, MD substitutes the TTM equation for the lattice temperature. Simulations are performed with both MD and TTM-MD models for an EAM Al target shocked at 300 kbar. The target includes a tilt grain boundary, which provides a region where shock heating is more pronounced and, therefore, the effect of the electronic heat conduction is expected to be more important. We find that the differences between the predictions of the MD and TTM-MD simulations are significantly smaller as compared to the hydrodynamics calculations performed at similar conditions with and without electronic heat conduction.

  11. Heat shock proteins and hypometabolism: adaptive strategy for proteome preservation

    Directory of Open Access Journals (Sweden)

    Storey KB

    2011-03-01

    Full Text Available Kenneth B Storey, Janet M StoreyDepartments of Biology and Chemistry, Carleton University, Ottawa, ON, CanadaAbstract: To survive under harsh environmental conditions many organisms retreat into hypometabolic states where metabolic rate may be reduced by 80% or more and energy use is reprioritized to emphasize key functions that sustain viability and provide cytoprotection. ATP-expensive activities, such as gene expression, protein turnover (synthesis and degradation, and the cell cycle, are largely shut down. As a consequence, mechanisms that stabilize the existing cellular proteome can become critical for long-term survival. Heat shock proteins (HSPs are well-known for their actions as chaperones that act to fold new proteins or refold proteins that are damaged. Indeed, they are part of the “minimal stress proteome” that appears to be a ubiquitous response by all cells as they attempt, successfully or unsuccessfully, to deal with stress. The present review summarizes evidence that HSPs are also a conserved feature of natural animal hypometabolism including the phenomena of estivation, hibernation, diapause, cold-hardiness, anaerobiosis, and anhydrobiosis. That is, organisms that retreat into dormant or torpid states in anticipation that environmental conditions may become too difficult for normal life also integrate the use of HSPs to protect their proteome while hypometabolic. Multiple studies show a common upregulation of expression of hsp genes and/or HSP proteins prior to or during hypometabolism in organisms as diverse as ground squirrels, turtles, land snails, insects, and brine shrimp and in situations of both preprogrammed dormancies (eg, seasonal or life stage specific and opportunistic hypometabolism (eg, triggered by desiccation or lack of oxygen. Hence, HSPs are not just a “shock” response that attempts to rescue cells from damaging stress but are a key protective strategy that is an integral component of natural states of

  12. THEORY AND EXPERIMENT ON THE VISCOUS HEATING OF FLUID DAMPER UNDER SHOCK ENVIRONMENT

    Institute of Scientific and Technical Information of China (English)

    CHU Deying; ZHANG Zhiyi; WANG Gongxian; HUA Hongxing; WANG Yu

    2008-01-01

    A specially designed fluid damper used as negative shock pulse generator in the shock resistance test system to dissipate the shock input energy in transient time duration is presented. The theoretical modeling based on the three-dimensional equation of heat transfer through a fluid element is created to predict the viscous heating in the fluid damper under shock conditions. A comprehensive experimental program that investigates the problem of viscous heating in the fluid damper under different shock conditions is conducted on the shock test machine to validate the analytical expression. Temperature histories for the fluid within the damper at two locations, the annular-orifice and the-end-of stroke of the damper, are recorded. The experimental results show that the theoretical model can offer a very dependable prediction for the temperature histories in the damper for increasing input velocity. The theoretical model and experimental data both clearly indicate that the viscous heating in the damper is directly related to the maximum shock velocity input and the pressure between the two sides of the piston head.

  13. Network analysis of oyster transcriptome revealed a cascade of cellular responses during recovery after heat shock.

    Directory of Open Access Journals (Sweden)

    Lingling Zhang

    Full Text Available Oysters, as a major group of marine bivalves, can tolerate a wide range of natural and anthropogenic stressors including heat stress. Recent studies have shown that oysters pretreated with heat shock can result in induced heat tolerance. A systematic study of cellular recovery from heat shock may provide insights into the mechanism of acquired thermal tolerance. In this study, we performed the first network analysis of oyster transcriptome by reanalyzing microarray data from a previous study. Network analysis revealed a cascade of cellular responses during oyster recovery after heat shock and identified responsive gene modules and key genes. Our study demonstrates the power of network analysis in a non-model organism with poor gene annotations, which can lead to new discoveries that go beyond the focus on individual genes.

  14. Global transcriptional analysis of Bacillus licheniformis reveals an overlap between heat shock and iron limitation stimulon.

    Science.gov (United States)

    Nielsen, Allan K; Breüner, Anne; Krzystanek, Marcin; Andersen, Jens T; Poulsen, Thomas A; Olsen, Peter B; Mijakovic, Ivan; Rasmussen, Michael D

    2010-01-01

    In this study, we characterized the heat shock stimulon of the important industrial microorganism Bacillus licheniformis using DNA microarrays. While sharing a high degree of homology with the closely related model organism Bacillus subtilis, the heat shock stimulon of B. licheniformis exhibited several novel and unexpected features. Most notably, heat shock in B. licheniformis resulted in decreased amounts of mRNA from the ytrABCEF operon, encoding a putative acetoin uptake system, and stimulated the transcription of purine biosynthesis and iron uptake genes. Unexpectedly, deletion of the ytrEF genes did not affect acetoin uptake, but increased heat sensitivity. To investigate the connection between heat stress and iron uptake further, we analyzed the iron limitation response of B. licheniformis by DNA microarrays and concluded that the response mostly involves the genes related to iron uptake and metabolism, while the only heat shock gene affected by iron limitation was clpE. We also attempted to delete the fur gene (encoding the ferric uptake repressor), but unexpectedly found it to be essential in B. licheniformis. Using the fluorescent protein-encoding reporter gene under control of the dhb promoter, which responded to both heat shock and iron-starvation, we confirmed the overlap between these responses.

  15. Possible involvement of phosphorylated heat-shock factor-1 in changes in heat shock protein 72 induction in the failing rat heart following myocardial infarction.

    Science.gov (United States)

    Marunouchi, Tetsuro; Murata, Mao; Takagi, Norio; Tanonaka, Kouichi

    2013-01-01

    It is supposed that an increase in the level of heat shock protein 72 (HSP72) in the failing heart would be beneficial for reducing the myocardial damage. However, the induction of HSP72 after an exposure to heat shock is blunted in the failing rat heart following myocardial infarction. In this study, to clarify the possible mechanisms underlying this reduction in the ability for HSP72 induction in the failing heart, the possible involvement of heat-shock factor-1 (HSF1), an HSP transcription factor, in this reduction was examined. When hemodynamic parameters of rats with myocardial infarction 8 weeks after coronary artery ligation were measured, the animals showed the signs of chronic heart failure. The HSF1 content was increased in the viable myocardium in the failing heart. The ability to induce cardiac HSP72 was reduced after an exposure to hyperthermia. The level of HSF1 in the cytosolic fraction from the failing heart with or without exposure to hyperthermia was increased, whereas that of HSF1 in the nuclear fraction was reduced. In the failing heart, the level of HSF1 on its serine 303 (Ser303) residue, which phosphorylation represses HSF1, was increased. These findings suggest that HSF1 translocation from the cytosol into the nucleus was attenuated after an exposure to hyperthermia and that an increase in the phosphorylation of HSF1 Ser303 was involved in the impairment of heat shock-induced HSP72 induction in the failing heart following myocardial infarction.

  16. A thermochemical model for shock-induced reactions (heat detonations) in solids

    Energy Technology Data Exchange (ETDEWEB)

    Boslough, M.B. (Sandia National Laboratories, Albuquerque, New Mexico 87185 (US))

    1990-02-01

    Recent advances in studies of shock-induced chemistry in reactive solids have led to the recognition of a new class of energetic materials which are unique in their response to shock waves. Experimental work has shown that chemical energy can be released on a time scale shorter than shock-transit times in laboratory samples. However, for many compositions, the reaction products remain in the condensed state upon release from high pressure, and no sudden expansion takes place. Nevertheless, if such a reaction is sufficiently rapid, it can be modeled as a type of detonation, termed heat detonation'' in the present paper. It is shown that unlike an explosive detonation, an unsupported heat detonation will decay to zero unless certain conditions are met. An example of such a reaction is Fe{sub 2}O{sub 3} +2Al+shock{r arrow}Al{sub 2} O{sub 3} +2Fe (the standard thermite reaction). A shock-wave equation of state is determined from a mixture theory for reacted and unreacted porous thermite. The calculated shock temperatures are compared to experimentally measured shock temperatures, demonstrating that a shock-induced reaction takes place. Interpretation of the measured temperature history in the context of the thermochemical model implies that the principal rate-controlling kinetic mechanism is dynamic mixing at the shock front. Despite the similarity in thermochemical modeling of heat detonations to explosive detonations, the two processes are qualitatively very different in reaction mechanism as well as in the form the energy takes upon release, with explosives producing mostly work and heat detonations producing mostly heat.

  17. Relationship between the induction of heat shock proteins and the decrease in glucocorticoid receptor during heat shock response in human osteosarcoma cells

    Institute of Scientific and Technical Information of China (English)

    宋亮年

    1995-01-01

    Previously,it has been found that glucocorticoid receptor(GR)binding activity decreasedrapidly during heat shock response in HOS-8603,a human osteosarcorna cell line.In this study,Therelationship between the induction of heat shock proteins(HSPs)and the decrease in GR was furtherstudied in the same cell line.It was found that even though quercetin could specifically inhibit the ex-pression of hsp90α and hsp70 mRNA,it could not prevent GR from the decrease in response to the heatshock treatment.This represents the first reported evidence that the induction of HSPs and the decrease inGR during heat shock response were 2 independent biological events.The results of the present study furthershowed that although the heat shock treatment alone had no effects on alkaline phosphatase(AKP)activity,itcould completely block the induction of AKP activity in HOS-8603 cells by dexamethasone(Dex),a syntheticglucocorticoid.These results demonstrate that the heat shock-induced alteration in GR was accompanied by adecrease in GR functional activity.Furthermore,when the induction of HSPs was inhibited by the treatmentof cells with quercetin,the stimulatory effects of Dex on AKP activity could still be inhibited completely bythe heat shock treatment.The results of this part,on the basis of GR functional activity,further demonstratethat quercetin could not inhibit the heat shock-induced decrease in GR,even though it could inhibit the induc-tion of HSPs.To clarify further the effects of quercetin alone on GR binding activity in HOS-8603 cells,theregulation of GR by quercetin was also studied.It was found for the first time that quercetin coulddown-regulate GR in a time-dependent manner significantly,and that the down-regulation of GR by quercetinin HOS-8603 cells paralelled with a decrease in glucocorticoid-mediated functional responses,suggesting thatthe down-regulation of GR by quercetin is of biological significance.

  18. Heat shock protein90 in lobular neoplasia of the breast

    Directory of Open Access Journals (Sweden)

    Patsouris Efstratios

    2008-10-01

    Full Text Available Abstract Background Heat shock protein 90 (Hsp90 overexpression has been implicated in breast carcinogenesis, with putative prognostic and therapeutic implications. The purpose of this study is to evaluate the immunohistochemical expression of Hsp90 and to examine whether Hsp90 expression is associated with estrogen receptor alpha (ER-alpha and beta (ER-beta immunostaining in lobular neoplasia (LN of the breast. Methods Tissue specimens were taken from 44 patients with LN. Immunohistochemical assessment of Hsp90, ER-alpha and ER-beta was performed both in the lesion and the adjacent normal breast ducts and lobules; the latter serving as control. As far as Hsp90 evaluation is concerned: i the percentage of positive cells, and ii the intensity was separately analyzed. Additionally, the Allred score was adopted and calculated. Accordingly, Allred score was separately evaluated for ER-alpha and ER-beta. The intensity was treated as an ordinal variable-score (0: negative, low: 1, moderate: 2, high: 3. Statistical analysis followed. Results Hsp90 immunoreactivity was mainly cytoplasmic in both the epithelial cells of normal breast (ducts and lobules and LN. Some epithelial cells of LN also showed nuclear staining, but all the LN foci mainly disclosed a positive cytoplasmic immunoreaction for Hsp90. In addition, rare intralobular inflammatory cells showed a slight immunoreaction. The percentage of Hsp90 positive cells in the LN areas was equal to 67.1 ± 12.2%, whereas the respective percentage in the normal adjacent breast tissue was 69.1 ± 11.6%; the difference was not statistically significant. The intensity score of Hsp90 staining was 1.82 ± 0.72 in LN foci, while in the normal adjacent tissue the intensity score was 2.14 ± 0.64. This difference was statistically significant (p = 0.029, Wilcoxon matched-pairs signed-ranks test. The Hsp90 Allred score was 6.46 ± 1.14 in the LN foci, significantly lower than in the normal adjacent tissue (6.91

  19. Olfactory conditioning in the third instar larvae of Drosophila melanogaster using heat shock reinforcement.

    Science.gov (United States)

    Khurana, Sukant; Robinson, Brooks G; Wang, Zihe; Shropshire, William C; Zhong, Allen C; Garcia, Laura E; Corpuz, Jonathan; Chow, Jonathan; Hatch, Michael M; Precise, Eric F; Cady, Amanda; Godinez, Ryan M; Pulpanyawong, Terapat; Nguyen, Andrew T; Li, Wen-Ke; Seiter, Max; Jahanian, Kambiz; Sun, Jeffrey C; Shah, Ruchita; Rajani, Sunaina; Chen, William Y; Ray, Sofia; Ryazanova, Natalie V; Wakou, Dorah; Prabhu, Rohith K; Atkinson, Nigel S

    2012-01-01

    Adult Drosophila melanogaster has long been a popular model for learning and memory studies. Now the larval stage of the fruit fly is also being used in an increasing number of classical conditioning studies. In this study, we employed heat shock as a novel negative reinforcement for larvae and obtained high learning scores following just one training trial. We demonstrated heat-shock conditioning in both reciprocal and non-reciprocal paradigms and observed that the time window of association for the odor and heat shock reinforcement is on the order of a few minutes. This is slightly wider than the time window for electroshock conditioning reported in previous studies, possibly due to lingering effects of the high temperature. To test the utility of this simplified assay for the identification of new mutations that disrupt learning, we examined flies carrying mutations in the dnc gene. While the sensitivity to heat shock, as tested by writhing, was similar for wild type and dnc homozygotes, dnc mutations strongly diminished learning. We confirmed that the learning defect in dnc flies was indeed due to mutation in the dnc gene using non-complementation analysis. Given that heat shock has not been employed as a reinforcement for larvae in the past, we explored learning as a function of heat shock intensity and found that optimal learning occurred around 41 °C, with higher and lower temperatures both resulting in lower learning scores. In summary, we have developed a very simple, robust paradigm of learning in fruit fly larvae using heat shock reinforcement.

  20. Lysosomal responses to heat-shock of seasonal temperature extremes in Cd-exposed mussels.

    Science.gov (United States)

    Múgica, M; Izagirre, U; Marigómez, I

    2015-07-01

    The present study was aimed at determining the effect of temperature extremes on lysosomal biomarkers in mussels exposed to a model toxic pollutant (Cd) at different seasons. For this purpose, temperature was elevated 10°C (from 12°C to 22°C in winter and from 18°C to 28°C in summer) for a period of 6h (heat-shock) in control and Cd-exposed mussels, and then returned back to initial one. Lysosomal membrane stability and lysosomal structural changes in digestive gland were investigated. In winter, heat-shock reduced the labilisation period (LP) of the lysosomal membrane, especially in Cd-exposed mussels, and provoked transient lysosomal enlargement. LP values recovered after the heat-shock cessation but lysosomal enlargement prevailed in both experimental groups. In summer, heat-shock induced remarkable reduction in LP and lysosomal enlargement (more markedly in Cd-exposed mussels), which recovered within 3 days. Besides, whilst heat-shock effects on LP were practically identical for Cd-exposed mussels in winter and summer, the effects were longer-lasting in summer than in winter for control mussels. Thus, lysosomal responsiveness after heat-shock was higher in summer than in winter but recovery was faster as well, and therefore the consequences of the heat shock seem to be more decisive in winter. In contrast, inter-season differences were attenuated in the presence of Cd. Consequently, mussels seem to be better prepared in summer than in winter to stand short periods of abrupt temperature change; this is, however, compromised when mussels are exposed to pollutants such as Cd.

  1. Effect of heat shock on the susceptibility ofFrankliniella occidentalis (Thysanoptera:Thripidae) to insecticides

    Institute of Scientific and Technical Information of China (English)

    ZHANG Bin; ZUO Tai-qiang; LI Hong-gang; SUN Li-juan; WANG Si-fang; ZHENG Chang-ying; WAN Fang-hao

    2016-01-01

    Currently, insecticides are considered as the primary approach for controling western lfower thrips,Frankliniela occidentalis (Pergande) (Thysanoptera: Thripidae). However, the heavy use of insecticides resulted in high insect resistance and serious environmental polution. Given its characteristics of ease of operation and environmental friendliness, insect control using high temperature is receiving considerable renewed research interest. However, although the combination of insecticides and high temperature to controlF. occidentalis has been studied before, few studies have focused on the short-term effect of such treatment. In a laboratory study,F. occidentalis adults and second-instar nymphs were exposed to 45°C for 2 h. Then, their susceptibility to acetamiprid, spinosad, methomyl, and beta-cypermethrin was tested after different periods of recovery time (2–36 h). Additionaly, the speciifc activity of three detoxiifcation enzymes (esterase, glutathioneS-trans-ferase, and cytochrome p450 (CYP) monooxygenase) of the treated insects was determined. The results indicated that the lfuctuation of susceptibility to insecticides and detoxiifcation enzyme activity duringF. occidentalis recovery from heat shock are related. Furthermore, several recovery time points (2, 30, and 36 h) of signiifcant susceptibility to four tested insecticides compared with the control were found during the treatment of adults that were heat-shocked. Recovery time points of higher susceptibility compared with the control depended on different insecticides during the second-instar nymph recovery from heat shock. Interestingly, the lfuctuation of CYP monooxygenase activity exhibited a trend that was similar to the lfuctuation of susceptibility to insecticides (especialy spinosad) during the recovery from heat shock of adults. In addition, the glutathioneS-transferase and CYP monooxygenase activity trend was similar to the trend of susceptibility to spinosad during the recovery from heat

  2. Genetic variation in heat shock protein 70 is associated with septic shock: narrowing the association to a specific haplotype.

    Science.gov (United States)

    Kee, C; Cheong, K Y; Pham, K; Waterer, G W; Temple, S E L

    2008-12-01

    Heat shock protein 70 (HSP70) plays a major role in immune responses. Polymorphisms within the gene have been associated with development of septic shock. This study refines the region of the HSP70 gene associated with development of septic shock and confirms its functionality. Subjects (n = 31) were grouped into one of three haplotypes based on their HSPA1B-179C>T and HSPA1B1267A>G genotypes. Mononuclear cells from these subjects were stimulated with heat-killed bacteria (10(7 )colony-forming units/mL Escherichia coli or Streptococcus pneumoniae) for 8 and 21 h. HSP70 and tumour necrosis factor (TNF) mRNA and protein levels were measured by reverse transcriptase-polymerase chain reaction and ELISA, respectively. The HSPA1B-179*C:1267*A haplotype was associated with significantly lower levels of HSPA1B mRNA and protein and higher production of TNF mRNA and protein compared to the other haplotypes. Induction of HSP70 was TNF independent. These results suggest that the HSPA1B-179C>T:1267A>G haplotype is functional and may explain the association of the HSP70 gene with development of septic shock.

  3. Differential heat shock response of primary human cell cultures and established cell lines

    DEFF Research Database (Denmark)

    Richter, W W; Issinger, O G

    1986-01-01

    degrees C treatment, whereas in immortalized cell lines usually 90% of the cells were found in suspension. Enhanced expression of the major heat shock protein (hsp 70) was found in all heat-treated cells. In contrast to the primary cell cultures, established and transformed cell lines synthesized...

  4. Heat-shock effects on photosynthesis and sink-source dynamics in wheat (Triticum aestivum L.)

    NARCIS (Netherlands)

    Schapendonk, A.H.C.M.; Xu, H.Y.; Putten, van der P.E.L.; Spiertz, J.H.J.

    2007-01-01

    To assess the mechanisms causing genotypic differences in heat tolerance of wheat (Triticum aestivum L.), physiological responses to a heat shock in a vegetative (`end of tillering¿) or a reproductive (`early grain filling¿) stage were studied. Three cultivars ¿ Lavett, Ciano-79 and Attila ¿

  5. Stimulation of cysteinyl leukotriene production in mast cells by heat shock and acetylsalicylic acid.

    Science.gov (United States)

    Mortaz, Esmaeil; Redegeld, Frank A; Dunsmore, Kathy; Odoms, Kelli; Wong, Hector R; Nijkamp, Frans P; Engels, Ferdi

    2007-04-30

    Immunoglobulin (Ig) E-dependent activation of mast cells is central to the allergic response. The engagement of IgE-occupied receptors initiates a series of molecular events that causes the release of preformed, and de novo synthesis of, allergic mediators. Cysteinyl leukotrienes are able to contract airway smooth muscle and increase mucus secretion and vascular permeability and recruit eosinophils. Mast cells have also recently been recognized as active participants in innate immune responses. Heat stress can modulate innate immunity by inducing stress proteins such as heat-shock proteins (HSPs). We previously demonstrated that treatment of mast cells with heat shock or acetylsalicylic acid results in an increase of TNF-alpha and IL-6 release. This effect was paralleled by expression of HSP70. In the current study, we further investigated the effects of heat shock and acetylsalicylic acid on the activation of mast cells and the release of cysteinyl leukotrienes. In mouse mast cells, derived from a culture of bone marrow cells, responsiveness to heat shock, acetylsalicylic acid and exogenous or endogenous HSP70 was monitored by measuring leukotriene C4 release. We show that after heat shock treatment and exposure to acetylsalicylic acid leukotriene production was increased. Moreover, exogenous rHSP70 also induced leukotriene production. Because it has been reported that leukotriene production in mast cells may be mediated by Toll like receptor (TLR) activation, and HSP70 also activates TLRs signaling, we further explored these issues by using mast cells that are not able to produce HSP70, i.e. heat shock factor-1 (HSF-1) knockout cells. We found that in HSF-1 knockout bone marrow derived mast cells, heat shock and acetylsalicylic acid failed to induce release of leukotrienes. Moreover, in wild type cells the surface expression of TLR4 was attenuated, whereas the intracellular expression was up-regulated. We conclude that heat shock and acetylsalicylic acid induce

  6. Flat plate heat transfer for laminar transition and turbulent boundary layers using a shock tube

    Science.gov (United States)

    Brostmeyer, J. D.; Nagamatsu, H. T.

    1984-01-01

    Heat transfer results are presented for laminar, transition, and turbulent boundary layers for a Mach number of 0.12 with gas temperatures of 425 K and 1000 K over a flat plate at room temperature. The measurements were made in air for a Reynolds number range of 600 to 6 million. The heat transfer measurements were conducted in a 70-ft long, 4 in. diameter shock tube. Reflecting wedges were used to reflect the incident shock wave to produce a flow Mach number of 0.12 behind the reflected shock wave. Thin film platinum heat gages were mounted on the plate surface to measure the local heat flux. The laminar results for gas temperatures of 425 K to 1000 K agree well with theory. The turbulent results are also close to incompressible theory, with the 1000 K flow case being slightly higher. The transition results lie between the laminar and turbulent predictions.

  7. Heat-flow equation motivated by the ideal-gas shock wave.

    Science.gov (United States)

    Holian, Brad Lee; Mareschal, Michel

    2010-08-01

    We present an equation for the heat-flux vector that goes beyond Fourier's Law of heat conduction, in order to model shockwave propagation in gases. Our approach is motivated by the observation of a disequilibrium among the three components of temperature, namely, the difference between the temperature component in the direction of a planar shock wave, versus those in the transverse directions. This difference is most prominent near the shock front. We test our heat-flow equation for the case of strong shock waves in the ideal gas, which has been studied in the past and compared to Navier-Stokes solutions. The new heat-flow treatment improves the agreement with nonequilibrium molecular-dynamics simulations of hard spheres under strong shockwave conditions.

  8. Heat shock protein 90 is a potential therapeutic target for ameliorating skeletal muscle abnormalities in Parkinson’s disease

    Institute of Scientific and Technical Information of China (English)

    Nour Erekat; Ahed Al-Khatib; Muhammed Al-Jarrah

    2014-01-01

    Previous studies have conifrmed that heat shock protein 90 overexpression can lead to dopami-nergic neuronal death. This study was designed to further investigate what effects are produced by heat shock protein 90 after endurance exercise training. Immunohistochemistry results showed that exercise training signiifcantly inhibited heat shock protein 90 overexpression in the soleus and gastrocnemius in Parkinson’s disease rats, which is a potential therapeutic target for ameliorating skeletal muscle abnormalities in Parkinson’s disease.

  9. Antibodies to two major chicken heat shock proteins cross-react with similar proteins in widely divergent species.

    OpenAIRE

    Kelley, P M; Schlesinger, M J

    1982-01-01

    Three of the proteins induced by heat shock of chicken embryo fibroblasts have been purified, and rabbit antibodies have been raised against them. These antibodies have been used in radioimmune precipitation reactions and in a solid-phase immune assay to detect antigenic material in non-heat-shocked chicken tissues and in extracts of widely different species ranging from yeast to mammalian tissue culture cells and human erythrocyte ghosts. Antibodies to two of the major chicken heat shock pro...

  10. Normal human epidermal keratinocytes treated with 7-dehydrocholesterol express increased levels of heat shock protein.

    Science.gov (United States)

    Mammone, Thomas; Muizzuddin, Neelam; Goyarts, Earl; Gan, David; Giacomoni, Paolo; Marenus, Ken; Maes, Daniel

    2004-01-01

    Human skin, and its isolated cells, respond to insults with a variety of repair and protective mechanisms. One such mechanism is the production of heat shock proteins (HSPs). Heat shock proteins help the other cellular proteins fold correctly into their active three-dimensional structures. Therefore, they can enhance the survival of cells under harsh, denaturing conditions. In order to develop a means of promoting the heat shock response to prepare the skin to withstand insult, we are investigating materials that appear to protect the skin biologically. One such material is vitamin D3 and its precursors. We have observed that keratinocytes treated with 7-dehydrocholesterol (7-DHC), a precursor of vitamin D3, have increased levels of protein and mRNA for heat shock proteins. In addition, we observed that topically applied 7-DHC increases the minimal dose of UVB required to induce erythema. These data suggest that 7-DHC can induce heat shock proteins in skin keratinocytes and that they will be more resistant to UVB insult.

  11. Sleep deprivation increase the expression of inducible heat shock protein 70 in rat gastric mucosa

    Institute of Scientific and Technical Information of China (English)

    Xi-Zhong Shen1; Marcel W.L. Koo; Chi-Hin Cho

    2001-01-01

    AIM To .investigate if sleep deprivation is able to increase the expression of inducible heat shock protein 70 in gastric mucosa and its possible role in mucosal defense. METHODS Rats for sleep disruption were placed inside a computerized rotating drum, gastric mucosa was taken from rats with 1, 3 and 7 d sleep deprivation. RT-PCR,immunohistochemistry and Western blotting were used to determine the expression of heat shock protein 70.Ethanol (500 mL@ L 1, I.g.) was used to induce gastric muceea damage. RESULTS RT-PCR, Western blotting and immunostaining confirmed that the sleep deprivation as a stress resulted in significantly greater expression of inducible heat shock protein 70 in gastric mucosa of rats. After the 500mL@ L-1 ethanol challenge, the ulcer area found in the rats with 7 d sleep deprivation (19.15 ± 4.2) mm2 was significantly lower (P<0.01) than the corresponding control (53.7 ± 8.1) mm2. CONCLUSION Sleep deprivation as a stress, in addition to lowering the gastric mucosal barrier, is able to stimulate the expression of inducible heat shock protein 70 in gastric mucosa of rats, the heat shock protein 70 may play an important role in gastric mucosal protection.

  12. Arctigenin from Fructus Arctii is a novel suppressor of heat shock response in mammalian cells

    Science.gov (United States)

    Ishihara, Keiichi; Yamagishi, Nobuyuki; Saito, Youhei; Takasaki, Midori; Konoshima, Takao; Hatayama, Takumi

    2006-01-01

    Because heat shock proteins (Hsps) are involved in protecting cells and in the pathophysiology of diseases such as inflammation, cancer, and neurodegenerative disorders, the use of regulators of the expression of Hsps in mammalian cells seems to be useful as a potential therapeutic modality. To identify compounds that modulate the response to heat shock, we analyzed several natural products using a mammalian cell line containing an hsp promoter-regulated reporter gene. In this study, we found that an extract from Fructus Arctii markedly suppressed the expression of Hsp induced by heat shock. A component of the extract arctigenin, but not the component arctiin, suppressed the response at the level of the activation of heat shock transcription factor, the induction of mRNA, and the synthesis and accumulation of Hsp. Furthermore, arctigenin inhibited the acquisition of thermotolerance in mammalian cells, including cancer cells. Thus, arctigenin seemed to be a new suppressive regulator of heat shock response in mammalian cells, and may be useful for hyperthermia cancer therapy. PMID:16817321

  13. Induced Levels of Heat Shock Proteins in dnaK mutants of Lactococcus lactis

    DEFF Research Database (Denmark)

    Koch, Birgit; Hammer, Karin; Vogensen, Finn K.

    1998-01-01

    of the inferred substrate binding site of the DnaK protein, exhibits a pronounced temperature sensitive phenotype and shows altered regulation of the heat shock response. The expression of the heat shock proteins are increased at the normal growth temperature measured both as protein synthesis rates and m......, HrcA , is dependent of the chaperone function of the GroELS complex and that an insertion mutant in dnaK did not have any effect on the expression of the heat shock proteins. The present data from Lactococcus lactis suggest that the DnaK protein could be involved in maturation of the homologous Hrc......The bacterial heat shock response is characterized by the elevated expression of a number of chaperone complexes and proteases including the DnaK-GrpE-DnaJ and the GroELS chaperone complexes. In order to investigate the importance of the DnaK chaperone complex for the growth and the heat shock...

  14. Heat-shock and stress response of the parasitic nematode Haemonchus contortus.

    Science.gov (United States)

    van Leeuwen, M A

    1995-01-01

    Before and after a stress treatment, larval stages and adult worms of Haemonchus contortus were tested for the induction and expression of heat-shock proteins (HSPs) using immunoblot analysis with HSP70-and HSP65-specific monoclonal antibodies. Stress treatment or heat shock did not alter the signals obtained with these antibodies, but the amount of HSP70 differed between the successive stages. In addition, the different stages were metabolically labeled with [35S]-methionine during a temperature-shock or chemical treatment and proteins were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The shocks resulted in an altered protein pattern. New was the de novo expression of a 20-kDa protein of adult worms after anthelmintic treatment.

  15. PBX-9502 Shock Sensitivity Correlation with Specific Heat and Reactive Temperature Magnitudes

    Science.gov (United States)

    Billingsley, James

    2005-07-01

    This work is a supplementary follow-on to papers [1 and 2], presented in two previous SCCM conferences, that related plane impact shock sensitivity of CHNO energetic materials to specific heat (Cp per average atom) magnitude and reactive temperature (TR) conditions. More specifically, plane impact shock energy input that is equal to the thermal vibratory energy increment (the area under the Cp versus temperature data curve between an experimental temperature, TEXP, and a reactive temperature) is sufficient to cause shock induced reactions, up to and including detonation, in CHNO energetic materials. This statement is demonstratively verified at four different test temperatures for PBX-9502 in this proposed paper. *Billingsley, J. P., paper in Shock Compression of Condensed Matter -- 1995, AIP Conference Proceedings 370, Part I, pages 429 -- 432. *Billingsley, J. P., paper in Shock Compression of Condensed Matter -- 1999, AIP Conference Proceedings, 505, Part II, pages 899 -- 902.

  16. Shock initiation of the TATB based explosive PBX 9502 heated to ~ 76∘C

    Science.gov (United States)

    Gustavsen, Richard; Gehr, Russell; Bucholtz, Scott; Pacheco, Adam; Bartram, Brian

    2015-06-01

    Recently we reported on shock initiation of PBX 9502 (95 wt.% tri-amino-trinitro-benzene, 5 wt.% Kel-F800 binder) cooled to -55°C and to 77K Shock waves were generated by gas-gun driven plate impacts and reactive flow in the cooled PBX 9502 was measured with embedded electromagnetic gauges. Here we use similar methods to warm the explosive to ~ 76°C. The explosive sample is heated by warm air flowing through channels in an aluminum sample mounting plate and a copper tubing coil surrounding the sample. Temperature in the sample is monitored using six type-E thermocouples. Results show increased shock sensitivity; time and distance to detonation onset vs. initial shock pressure are shorter than when the sample is initially at ambient temperature. Our results are consistent with those reported by Dallman & Wackerle. Particle velocity wave profiles were also obtained during the shock-to-detonation transition and will be presented.

  17. Identification of Genes Differentially Expressed During Heat Shock Treatment in Aedes aegypti

    Science.gov (United States)

    2009-01-01

    expressions of a vector mosquito population. Several families of heat shock proteins (HSPs) are known to be expressed in insects and may have a...stress con- ditions (such as pathogen infection, heavy metal ions, hypoxia, and osmotic stress) in many other animals and insects including mosquitoes...shockÐtreated female Ae. aegypti may provide infor- mationneeded to identifyproteins critical tomosquito survival. Using RNAi technology to knock down these

  18. Effects of calmodulin on DNA-binding activity of heat shock transcription factor in vitro

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The DNA-binding activity of heat shock transcription factor (HSF) was induced by heat shock (HS) of a whole cell extract. Addition of antiserum, specific to CaM, to a whole cell extract reduced bind of the HSF to the heat shock element (HSE) with maize, and the re-addition of CaM to the sample restored the activity of the HSF for binding to HSE. In addition, DNA-binding activity of the HSF was also induced by directly adding CaM to a whole cell extract at non-HS temperature with maize. Similar results were obtained with wheat and tomato. Our observations provide the first example of the involvement of CaM in regulation of the DNA-binding activity of the HSF.

  19. Suppression of first cleavage in the Mexican axolotl (Ambystoma mexicanum) by heat shock or hydrostatic pressure

    Energy Technology Data Exchange (ETDEWEB)

    Gillespie, L.L.; Armstrong, J.B.

    1981-12-01

    Androgenetic diploid axolotls were produced by ultraviolet inactivation of the egg pronucleus shortly after fertilization, followed by suppression of the first cleavage division by hydrostatic pressure or heat shock. After treatment at 14,000 psi for 8 minutes, diploidy was restored in 74% of the embryos, but only 0.8% survived to hatching. A 36-37 degrees C heat shock of 10-minutes duration, applied 5.5 hours after the eggs were collected, yielded a slightly lower percentage of diploids. However, the proportion surviving to hatching was significantly greater (up to 4.6%). A second generation of androgenetic diploids was produced from one of the oldest of the first generation males with a similar degree of success. The lack of significant improvement suggests that the low survival is due to the heat shock per se and not to the uncovering of recessive lethal genes carried by the parent.

  20. Molecular cloning and expression of a hexameric Drosophila heat shock factor subject to negative regulation.

    Science.gov (United States)

    Clos, J; Westwood, J T; Becker, P B; Wilson, S; Lambert, K; Wu, C

    1990-11-30

    We report the cloning of the transcriptional activator of heat shock genes, HSF, from Drosophila. The predicted sequence of Drosophila HSF protein is surprisingly divergent from that of yeast HSF, except in regions important for DNA binding and oligomerization. A segment of the DNA binding domain of HSF bears an intriguing similarity to the putative DNA recognition helix of bacterial sigma factors, while the oligomerization domain contains an unusual arrangement of conserved hydrophobic heptad repeats. Drosophila HSF produced in E. coli under nonshock conditions forms a hexamer that binds specifically to DNA with high affinity and activates transcription from a heat shock promoter in vitro. In contrast, when HSF is expressed in Xenopus oocytes, maximal DNA binding affinity is observed only after heat shock induction. These results suggest that Drosophila HSF has an intrinsic affinity for DNA, which is repressed under nonshock conditions in vivo.

  1. Development of a Heat-Shock Inducible Gene Expression System in the Red Alga Cyanidioschyzon merolae

    Science.gov (United States)

    Sumiya, Nobuko; Fujiwara, Takayuki; Kobayashi, Yusuke; Misumi, Osami; Miyagishima, Shin-ya

    2014-01-01

    The cell of the unicellular red alga Cyanidioschyzon merolae contains a single chloroplast and mitochondrion, the division of which is tightly synchronized by a light/dark cycle. The genome content is extremely simple, with a low level of genetic redundancy, in photosynthetic eukaryotes. In addition, transient transformation and stable transformation by homologous recombination have been reported. However, for molecular genetic analyses of phenomena that are essential for cellular growth and survival, inducible gene expression/suppression systems are needed. Here, we report the development of a heat-shock inducible gene expression system in C. merolae. CMJ101C, encoding a small heat shock protein, is transcribed only when cells are exposed to an elevated temperature. Using a superfolder GFP as a reporter protein, the 200-bp upstream region of CMJ101C orf was determined to be the optimal promoter for heat-shock induction. The optimal temperature to induce expression is 50°C, at which C. merolae cells are able to proliferate. At least a 30-min heat shock is required for the expression of a protein of interest and a 60-min heat shock yields the maximum level of protein expression. After the heat shock, the mRNA level decreases rapidly. As an example of the system, the expression of a dominant negative form of chloroplast division DRP5B protein, which has a mutation in the GTPase domain, was induced. Expression of the dominant negative DRP5B resulted in the appearance of aberrant-shaped cells in which two daughter chloroplasts and the cells are still connected by a small DRP5B positive tube-like structure. This result suggests that the dominant negative DRP5B inhibited the final scission of the chloroplast division site, but not the earlier stages of division site constriction. It is also suggested that cell cycle progression is not arrested by the impairment of chloroplast division at the final stage. PMID:25337786

  2. Thermochemical model for shock-induced chemical reactions in porous thermite: The heat detonation model

    Energy Technology Data Exchange (ETDEWEB)

    Boslough, M.B.

    1989-01-01

    A thermochemical model has been developed that treats a shock-induced solid state chemical reaction as a special type of detonation, called a ''heat detonation'' to distinguish it from an ordinary explosive detonation and describe the final form that the chemical energy takes. According to shock temperature measurements, chemical energy can be released from porous reactive solids on a time scale shorter than shock-transit times in laboratory samples. By comparing the experimental shock temperature for porous thermite to that calculated by the model, the amount of thermite reacted when shocked to about 4 GPa was estimated to be between 60 and 70%. Calculated shock temperatures are extremely strong functions of the extent of reaction, but are relatively insensitive to the initial porosity and amount of volatile impurities. Thus, shock temperature measurements are the most useful for real-time studies of shock-induced exothermic chemical reactions in solids. 11 refs., 5 figs., 1 tab.

  3. Heat shock pretreatment enhances porcine myoblasts survival after autotransplantation in intact skeletal muscle

    Institute of Scientific and Technical Information of China (English)

    YANG Sheng; Thomas LAUMONIER; Jacques MENETREY

    2007-01-01

    Myoblast transplantation (MT) is a cell-based gene therapy treatment, representing a potential treatment for Duchenne muscular dystrophy (DMD), cardiac failure and muscle trauma. The rapid and massive death of transplanted cells after MT is considered as a major hurdle which limits the efficacy of MT treatment. Heat shock proteins (HSPs) are overexpressed when cells undergo various insults. HSPs have been described to protect cells in vivo and in vitro against diverse insults. The aim of our study is to investigate whether HSP overexpression could increase myoblast survival after autotransplantation in pig intact skeletal muscle. HSP expression was induced by warming the cells at 42℃ for 1 h. HSP70 expression was quantified by Western blot and flow cytometry 24 h after the treatment. To investigate the myogenic characteristics of myoblasts, desmin and CD56 were analysed by Western blot and flow cytometry; and the fusion index was measured. We also quantified cell survival after autologous transplantation in pig intact skeletal muscle and followed cell integration. Results showed that heat shock treatment of myoblasts induced a significative overexpression of the HSP70 (P<0.01) without loss of their myogenic characteristics as assessed by FACS and fusion index. In vivo (n=7), the myoblast survival rate was not significantly different at 24 h between heat shock treated and nontreated cells (67.69%±8.35% versus 58.79%±8.35%, P>0.05). However, the myoblast survival rate in the heat shocked cells increased by twofold at 48 h (53.32%±8.22% versus 28.27%±6.32%, P<0.01)and more than threefold at 120 h (26.33%±5.54% versus 8.79%±2.51%, P<0.01). Histological analysis showed the presence of non-heat shocked and heat shocked donor myoblasts fused with host myoblasts. These results suggested that heat shock pretreatment increased the HSP70 expression in porcine myoblasts, and improved the survival rate after autologous transplantation. Therefore, heat shock

  4. Heat shock pretreatment enhances porcine myoblasts survival after autotransplantation in intact skeletal muscle

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Myoblast transplantation (MT) is a cell-based gene therapy treatment, representing a potential treat-ment for Duchenne muscular dystrophy (DMD), cardiac failure and muscle trauma. The rapid and mas-sive death of transplanted cells after MT is considered as a major hurdle which limits the efficacy of MT treatment. Heat shock proteins (HSPs) are overexpressed when cells undergo various insults. HSPs have been described to protect cells in vivo and in vitro against diverse insults. The aim of our study is to investigate whether HSP overexpression could increase myoblast survival after autotransplantation in pig intact skeletal muscle. HSP expression was induced by warming the cells at 42℃ for 1 h. HSP70 expression was quantified by Western blot and flow cytometry 24 h after the treatment. To investigate the myogenic characteristics of myoblasts, desmin and CD56 were analysed by Western blot and flow cytometry; and the fusion index was measured. We also quantified cell survival after autologous transplantation in pig intact skeletal muscle and followed cell integration. Results showed that heat shock treatment of myoblasts induced a significative overexpression of the HSP70 (P < 0.01) without loss of their myogenic characteristics as assessed by FACS and fusion index. In vivo (n=7), the myoblast survival rate was not significantly different at 24 h between heat shock treated and non- treated cells (67.69% ± 8.35% versus 58.79% ± 8.35%, P > 0.05). However, the myoblast survival rate in the heat shocked cells increased by twofold at 48 h (53.32% ± 8.22% versus 28.27% ± 6.32%, P < 0.01) and more than threefold at 120 h (26.33% ± 5.54% versus 8.79% ± 2.51%, P < 0.01). Histological analy-sis showed the presence of non-heat shocked and heat shocked donor myoblasts fused with host myoblasts. These results suggested that heat shock pretreatment increased the HSP70 expression in porcine myoblasts, and improved the survival rate after autologous transplantation

  5. Expression of Heat Shock and Other Stress Response Proteins in Ticks and Cultured Tick Cells in Response to Anaplasma spp. Infection and Heat Shock

    Directory of Open Access Journals (Sweden)

    Margarita Villar

    2010-01-01

    Full Text Available Ticks are ectoparasites of animals and humans that serve as vectors of Anaplasma and other pathogens that affect humans and animals worldwide. Ticks and the pathogens that they transmit have coevolved molecular interactions involving genetic traits of both the tick and the pathogen that mediate their development and survival. In this paper, the expression of heat shock proteins (HSPs and other stress response proteins (SRPs was characterized in ticks and cultured tick cells by proteomics and transcriptomics analyses in response to Anaplasma spp. infection and heat shock. The results of these studies demonstrated that the stress response was activated in ticks and cultured tick cells after Anaplasma spp. infection and heat shock. However, in the natural vector-pathogen relationship, HSPs and other SRPs were not strongly activated, which likely resulted from tick-pathogen coevolution. These results also demonstrated pathogen- and tick-specific differences in the expression of HSPs and other SRPs in ticks and cultured tick cells infected with Anaplasma spp. and suggested the existence of post-transcriptional mechanisms induced by Anaplasma spp. to control tick response to infection. These results illustrated the complexity of the stress response in ticks and suggested a function for the HSPs and other SRPs during Anaplasma spp. infection.

  6. Effects of Heat Shock on Photosynthetic Properties, Antioxidant Enzyme Activity, and Downy Mildew of Cucumber (Cucumis sativus L.).

    Science.gov (United States)

    Ding, Xiaotao; Jiang, Yuping; Hao, Ting; Jin, Haijun; Zhang, Hongmei; He, Lizhong; Zhou, Qiang; Huang, Danfeng; Hui, Dafeng; Yu, Jizhu

    2016-01-01

    Heat shock is considered an abiotic stress for plant growth, but the effects of heat shock on physiological responses of cucumber plant leaves with and without downy mildew disease are still not clear. In this study, cucumber seedlings were exposed to heat shock in greenhouses, and the responses of photosynthetic properties, carbohydrate metabolism, antioxidant enzyme activity, osmolytes, and disease severity index of leaves with or without the downy mildew disease were measured. Results showed that heat shock significantly decreased the net photosynthetic rate, actual photochemical efficiency, photochemical quenching coefficient, and starch content. Heat shock caused an increase in the stomatal conductance, transpiration rate, antioxidant enzyme activities, total soluble sugar content, sucrose content, soluble protein content and proline content for both healthy leaves and downy mildew infected leaves. These results demonstrate that heat shock activated the transpiration pathway to protect the photosystem from damage due to excess energy in cucumber leaves. Potential resistance mechanisms of plants exposed to heat stress may involve higher osmotic regulation capacity related to an increase of total accumulations of soluble sugar, proline and soluble protein, as well as higher antioxidant enzymes activity in stressed leaves. Heat shock reduced downy mildew disease severity index by more than 50%, and clearly alleviated downy mildew development in the greenhouses. These findings indicate that cucumber may have a complex physiological change to resist short-term heat shock, and suppress the development of the downy mildew disease.

  7. Effects of Heat Shock on Photosynthetic Properties, Antioxidant Enzyme Activity, and Downy Mildew of Cucumber (Cucumis sativus L..

    Directory of Open Access Journals (Sweden)

    Xiaotao Ding

    Full Text Available Heat shock is considered an abiotic stress for plant growth, but the effects of heat shock on physiological responses of cucumber plant leaves with and without downy mildew disease are still not clear. In this study, cucumber seedlings were exposed to heat shock in greenhouses, and the responses of photosynthetic properties, carbohydrate metabolism, antioxidant enzyme activity, osmolytes, and disease severity index of leaves with or without the downy mildew disease were measured. Results showed that heat shock significantly decreased the net photosynthetic rate, actual photochemical efficiency, photochemical quenching coefficient, and starch content. Heat shock caused an increase in the stomatal conductance, transpiration rate, antioxidant enzyme activities, total soluble sugar content, sucrose content, soluble protein content and proline content for both healthy leaves and downy mildew infected leaves. These results demonstrate that heat shock activated the transpiration pathway to protect the photosystem from damage due to excess energy in cucumber leaves. Potential resistance mechanisms of plants exposed to heat stress may involve higher osmotic regulation capacity related to an increase of total accumulations of soluble sugar, proline and soluble protein, as well as higher antioxidant enzymes activity in stressed leaves. Heat shock reduced downy mildew disease severity index by more than 50%, and clearly alleviated downy mildew development in the greenhouses. These findings indicate that cucumber may have a complex physiological change to resist short-term heat shock, and suppress the development of the downy mildew disease.

  8. Heat shock factor 1 upregulates transcription of Epstein-Barr Virus nuclear antigen 1 by binding to a heat shock element within the BamHI-Q promoter

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Feng-Wei [The State Key Laboratory of Oncology in South China, Cancer Center, Sun Yat-Sen University, Guangzhou (China); Wu, Xian-Rui [Department of Surgery, Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou (China); Liu, Wen-Ju; Liao, Yi-Ji [The State Key Laboratory of Oncology in South China, Cancer Center, Sun Yat-Sen University, Guangzhou (China); Lin, Sheng [Laboratory of Integrated Biosciences, School of Life Science, Sun Yat-sen University, Guangzhou (China); Zong, Yong-Sheng; Zeng, Mu-Sheng; Zeng, Yi-Xin [The State Key Laboratory of Oncology in South China, Cancer Center, Sun Yat-Sen University, Guangzhou (China); Mai, Shi-Juan, E-mail: maishj@sysucc.org.cn [The State Key Laboratory of Oncology in South China, Cancer Center, Sun Yat-Sen University, Guangzhou (China); Xie, Dan, E-mail: xied@mail.sysu.edu.cn [The State Key Laboratory of Oncology in South China, Cancer Center, Sun Yat-Sen University, Guangzhou (China)

    2011-12-20

    Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) is essential for maintenance of the episome and establishment of latency. In this study, we observed that heat treatment effectively induced EBNA1 transcription in EBV-transformed B95-8 and human LCL cell lines. Although Cp is considered as the sole promoter used for the expression of EBNA1 transcripts in the lymphoblastoid cell lines, the RT-PCR results showed that the EBNA1 transcripts induced by heat treatment arise from Qp-initiated transcripts. Using bioinformatics, a high affinity and functional heat shock factor 1 (HSF1)-binding element within the - 17/+4 oligonucleotide of the Qp was found, and was determined by electrophoretic mobility shift assay and chromatin immunoprecipitation assay. Moreover, heat shock and exogenous HSF1 expression induced Qp activity in reporter assays. Further, RNA interference-mediated HSF1 gene silencing attenuated heat-induced EBNA1 expression in B95-8 cells. These results provide evidence that EBNA1 is a new target for the transcription factor HSF1.

  9. Heat shock proteins: in vivo heat treatments reveal adipose tissue depot-specific effects.

    Science.gov (United States)

    Rogers, Robert S; Beaudoin, Marie-Soleil; Wheatley, Joshua L; Wright, David C; Geiger, Paige C

    2015-01-01

    Heat treatments (HT) and the induction of heat shock proteins (HSPs) improve whole body and skeletal muscle insulin sensitivity while decreasing white adipose tissue (WAT) mass. However, HSPs in WAT have been understudied. The purpose of the present study was to examine patterns of HSP expression in WAT depots, and to examine the effects of a single in vivo HT on WAT metabolism. Male Wistar rats received HT (41°C, 20 min) or sham treatment (37°C), and 24 h later subcutaneous, epididymal, and retroperitoneal WAT depots (SCAT, eWAT, and rpWAT, respectively) were removed for ex vivo experiments and Western blotting. SCAT, eWAT, and rpWAT from a subset of rats were also cultured separately and received a single in vitro HT or sham treatment. HSP72 and HSP25 expression was greatest in more metabolically active WAT depots (i.e., eWAT and rpWAT) compared with the SCAT. Following HT, HSP72 increased in all depots with the greatest induction occurring in the SCAT. In addition, HSP25 increased in the rpWAT and eWAT, while HSP60 increased in the rpWAT only in vivo. Free fatty acid (FFA) release from WAT explants was increased following HT in the rpWAT only, and fatty acid reesterification was decreased in the rpWAT but increased in the SCAT following HT. HT increased insulin responsiveness in eWAT, but not in SCAT or rpWAT. Differences in HSP expression and induction patterns following HT further support the growing body of literature differentiating distinct WAT depots in health and disease.

  10. Plants contain a novel multi-member class of heat shock factors without transcriptional activator potential.

    Science.gov (United States)

    Czarnecka-Verner, E; Yuan, C X; Scharf, K D; Englich, G; Gurley, W B

    2000-07-01

    Based on phylogeny of DNA-binding domains and the organization of hydrophobic repeats, two families of heat shock transcription factors (HSFs) exist in plants. Class A HSFs are involved in the activation of the heat shock response, but the role of class B HSFs is not clear. When transcriptional activities of full-length HSFs were monitored in tobacco protoplasts, no class B HSFs from soybean or Arabidopsis showed activity under control or heat stress conditions. Additional assays confirmed the finding that the class B HSFs lacked the capacity to activate transcription. Fusion of a heterologous activation domain from human HSF1 (AD2) to the C-terminus of GmHSFB1-34 gave no evidence of synergistic enhancement of AD2 activity, which would be expected if weak activation domains were present. Furthermore, activity of AtHSFB1-4 (class B) was not rescued by coexpression with AtHSFA4-21 (class A) indicating that the class A HSF was not able to provide a missing function required for class B activity. The transcriptional activation potential of Arabidopsis AtHSFA4-21 was mapped primarily to a 39 amino acid fragment in the C-terminus enriched in bulky hydrophobic and acidic residues. Deletion mutagenesis of the C-terminal activator regions of tomato and Arabidopsis HSFs indicated that these plant HSFs lack heat-inducible regulatory regions analogous to those of mammalian HSF1. These findings suggest that heat shock regulation in plants may differ from metazoans by partitioning negative and positive functional domains onto separate HSF proteins. Class A HSFs are primarily responsible for stress-inducible activation of heat shock genes whereas some of the inert class B HSFs may be specialized for repression, or down-regulation, of the heat shock response.

  11. Induction of heat shock gene expression in RAT1 primary fibroblast cells by ELF electric fields.

    Science.gov (United States)

    Frisch, Paul; Li, Gloria C; McLeod, Kenneth; Laramee, Craig B

    2013-07-01

    Recent studies have demonstrated that the Ku70 gene fragment can be placed in the anti-sense orientation under the control of a heat-inducible heat shock protein 70 (HSP70) promoter and activated through heat shock exposure. This results in attenuation of the Ku70 protein expression, inhibiting cellular repair processes, and sensitizing the transfected cells to exposures such as the ionizing radiation exposures used clinically. However, achieving the tissue temperatures necessary to thermally induce the HSP70 response presents significant limitations to the clinical application of this strategy. Previous findings suggest an alternative approach to inducing a heat shock response, specifically through the use of extremely low frequency (ELF) electrical field stimulation. To further pursue this approach, we investigated HSP70 responses in transfected rat primary fibroblast (RAT1) cells exposed to 10 Hz electric fields at intensities of 20-500 V/m. We confirmed that low frequency electric fields can induce HSP70 heat shock expression, with peak responses obtained at 8 h following a 2 h field exposure. However, the approximate threefold increase in expression is substantially lower than that obtained using thermal stimulation, raising questions of the clinical utility of the response.

  12. A minimal titration model of the mammalian dynamical heat shock response

    Science.gov (United States)

    Sivéry, Aude; Courtade, Emmanuel; Thommen, Quentin

    2016-12-01

    Environmental stress, such as oxidative or heat stress, induces the activation of the heat shock response (HSR) and leads to an increase in the heat shock proteins (HSPs) level. These HSPs act as molecular chaperones to maintain cellular proteostasis. Controlled by highly intricate regulatory mechanisms, having stress-induced activation and feedback regulations with multiple partners, the HSR is still incompletely understood. In this context, we propose a minimal molecular model for the gene regulatory network of the HSR that reproduces quantitatively different heat shock experiments both on heat shock factor 1 (HSF1) and HSPs activities. This model, which is based on chemical kinetics laws, is kept with a low dimensionality without altering the biological interpretation of the model dynamics. This simplistic model highlights the titration of HSF1 by chaperones as the guiding line of the network. Moreover, by a steady states analysis of the network, three different temperature stress regimes appear: normal, acute, and chronic, where normal stress corresponds to pseudo thermal adaption. The protein triage that governs the fate of damaged proteins or the different stress regimes are consequences of the titration mechanism. The simplicity of the present model is of interest in order to study detailed modelling of cross regulation between the HSR and other major genetic networks like the cell cycle or the circadian clock.

  13. Test of a new heat-flow equation for dense-fluid shock waves.

    Science.gov (United States)

    Holian, Brad Lee; Mareschal, Michel; Ravelo, Ramon

    2010-09-21

    Using a recently proposed equation for the heat-flux vector that goes beyond Fourier's Law of heat conduction, we model shockwave propagation in the dense Lennard-Jones fluid. Disequilibrium among the three components of temperature, namely, the difference between the kinetic temperature in the direction of a planar shock wave and those in the transverse directions, particularly in the region near the shock front, gives rise to a new transport (equilibration) mechanism not seen in usual one-dimensional heat-flow situations. The modification of the heat-flow equation was tested earlier for the case of strong shock waves in the ideal gas, which had been studied in the past and compared to Navier-Stokes-Fourier solutions. Now, the Lennard-Jones fluid, whose equation of state and transport properties have been determined from independent calculations, allows us to study the case where potential, as well as kinetic contributions are important. The new heat-flow treatment improves the agreement with nonequilibrium molecular-dynamics simulations under strong shock wave conditions, compared to Navier-Stokes.

  14. Heat conduction: hyperbolic self-similar shock-waves in solids

    CERN Document Server

    Barna, Imre Ferenc

    2012-01-01

    Analytic solutions for cylindrical thermal waves in solid medium is given based on the nonlinear hyperbolic system of heat flux relaxation and energy conservation equations. The Fourier-Cattaneo phenomenological law is generalized where the relaxation time and heat propagation coefficient have a general power law temperature dependence. From such laws one cannot form a second order parabolic or telegraph-type equation. We consider the original non-linear hyperbolic system itself with the self-similar Ansatz for the temperature distribution and for the heat flux. As results continuous and shock-wave solutions are presented. For physical establishment numerous materials with various temperature dependent heat conduction coefficients are mentioned.

  15. HEAT SHOCK FACTOR 1-MEDIATED THERMOTOLERANCE PREVENTS CELL DEATH AND RESULTS IN G2/M CELL CYCLE ARREST

    Science.gov (United States)

    Mammalian cells respond to stress by activating heat shock transcription factors (e.g., HSF1) that regulate increased synthesis of heat shock proteins (HSPs). HSPs mediate protection from deleterious effects of stress by preventing permanent disruption of normal cellular mitosis...

  16. HEAT SHOCK FACTOR 1-MEDIATED THERMOTOLERANCE PREVENTS CELL DEATH AND RESULTS IN G2/M CELL CYCLE ARREST

    Science.gov (United States)

    Mammalian cells respond to stress by activating heat shock transcription factors (e.g., HSF1) that regulate increased synthesis of heat shock proteins (HSPs). HSPs mediate protection from deleterious effects of stress by preventing permanent disruption of normal cellular mitosis...

  17. Asymmetric shock heating and the terrestrial magma ocean origin of the Moon.

    Science.gov (United States)

    Karato, Shun-ichiro

    2014-01-01

    One of the difficulties of the current giant impact model for the origin of the Moon is to explain the marked similarity in the isotopic compositions and the substantial differences in the major element chemistry. Physics of shock heating is analyzed to show that the degree of heating is asymmetric between the impactor and the target, if the target (the proto-Earth) had a magma-ocean but the impactor did not. The magma ocean is heated much more than the solid impactor and the vapor-rich jets come mainly from the magma-ocean from which the Moon might have been formed. In this scenario, the similarity and differences in the composition between the Moon and Earth would be explained as a natural consequence of a collision in the later stage of planetary formation. Including the asymmetry in shock heating is the first step toward explaining the chemical composition of the Moon.

  18. Translational control of small heat shock genes in mesophilic and thermophilic cyanobacteria by RNA thermometers.

    Science.gov (United States)

    Cimdins, Annika; Klinkert, Birgit; Aschke-Sonnenborn, Ursula; Kaiser, Friederike M; Kortmann, Jens; Narberhaus, Franz

    2014-01-01

    Cyanobacteria constitute a heterogeneous phylum of oxygen-producing, photosynthetic prokaryotes. They are susceptible to various stress conditions like heat, salt, or light stress, all inducing the cyanobacterial heat shock response (HSR). Cyanobacterial small heat shock proteins (sHsps) are known to preserve thylakoid membrane integrity under stress conditions, thereby protecting the photosynthesis machinery. In Synechocystis sp PCC 6803, synthesis of the sHsp Hsp17 is regulated by an RNA thermometer (RNAT) in the 5'-untranslated region (5'-UTR) of the hsp17 mRNA. RNATs are direct temperature sensors that control expression of many bacterial heat shock and virulence genes. They hinder translation at low temperatures by base pairing, thus blocking ribosome access to the mRNA.   To explore the temperature range in which RNATs act, we studied various RNAT candidates upstream of sHsp genes from mesophilic and thermophilic cyanobacteria. The mesophilic cyanobacteria Anabaena variabilis and Nostoc sp chromosomally encode two sHsps each. Reporter gene studies suggested RNAT-mediated post-transcriptional regulation of shsp expression in both organisms. Detailed structural analysis of the two A. variabilis candidates revealed two novel RNAT types. The first, avashort, regulates translation primarily by masking of the AUG translational start codon. The second, featuring an extended initial hairpin, thus named avalong, presumably makes use of complex tertiary interaction. The 5'-UTR of the small heat shock gene hspA in the thermophile Thermosynechococcus elongatus is predicted to adopt an extended secondary structure. Structure probing revealed that the ribosome binding site was blocked at temperatures below 55 °C. The results of this study demonstrate that cyanobacteria commonly use RNATs to control expression of their small heat shock genes.

  19. The Role of Heat Shock Response in Insulin Resistance and Diabetes

    OpenAIRE

    Tatsuya Kondo; Hiroyuki Motoshima; Motoyuki Igata; Junji Kawashima; Takeshi Matsumura; Hirofumi Kai; Eiichi Araki

    2014-01-01

    The expansion of life-style related diseases, such as metabolic syndrome (MS) and type 2 diabetes mellitus (T2DM), appears to be unstoppable. It is also difficult to cease their complications in spite of many antidiabetic medications or intervention of public administration. We and our collaborators found that physical medicine using simultaneous stimulation of heat with mild electric current activates heat shock response, thereby reducing visceral adiposity, insulin resistance, chronic infla...

  20. Effects of heat shock, stannous chloride, and gallium nitrate on the rat inflammatory response

    OpenAIRE

    House, S.D.; Guidon, P T; Perdrizet, G.A.; Rewinski, M.; Kyriakos, R.; Bockman, R S; Mistry, T.; Gallagher, P.A.; Hightower, L E

    2001-01-01

    Heat and a variety of other stressors cause mammalian cells and tissues to acquire cytoprotection. This transient state of altered cellular physiology is nonproliferative and antiapoptotic. In this study, male Wistar rats were stress conditioned with either stannous chloride or gallium nitrate, which have immunosuppressive effects in vivo and in vitro, or heat shock, the most intensively studied inducer of cytoprotection. The early stages of inflammation in response to topical suffusion of me...

  1. The Role of Heat Shock Response in Insulin Resistance and Diabetes

    OpenAIRE

    Tatsuya Kondo; Hiroyuki Motoshima; Motoyuki Igata; Junji Kawashima; Takeshi Matsumura; Hirofumi Kai; Eiichi Araki

    2014-01-01

    The expansion of life-style related diseases, such as metabolic syndrome (MS) and type 2 diabetes mellitus (T2DM), appears to be unstoppable. It is also difficult to cease their complications in spite of many antidiabetic medications or intervention of public administration. We and our collaborators found that physical medicine using simultaneous stimulation of heat with mild electric current activates heat shock response, thereby reducing visceral adiposity, insulin resistance, chronic infla...

  2. Fe I oscillator strengths determined from anomalous dispersion of shock-heated gases.

    Science.gov (United States)

    Huber, M. C. E.; Parkinson, W. H.

    1972-01-01

    Determination of Fe I oscillator strengths by the hook method on shock-heated gases. Within the given errors these values agree with oscillator strengths obtained by other methods, including wall-stabilized arc and shock-tube emission, the beam-foil technique, and delayed-coincidence measurements, except that the data reported in the present article tend to be somewhat higher. If it is assumed that no change occurs in atmospheric models, the authors' f-value scale would suggest a solar abundance at the lower limit of the recently published values - namely, log (A sub Fe/A sub H) + 12 = 7.4. This study demonstrates the effectiveness of the hook method for quantitative spectroscopy on shock-heated gases and points up its usefulness for gas diagnostics on optically thick lines.

  3. The long-term effects of a life-prolonging heat treatment on the Drosophila melanogaster transcriptome suggest that heat shock proteins extend lifespan

    DEFF Research Database (Denmark)

    Sarup, Pernille Merete; Sørensen, Peter; Loeschcke, Volker

    2014-01-01

    -treated flies. Several hsp70 probe sets were up-regulated 1.7–2-fold in the mildly stressed flies weeks after the last heat treatment (P heat shock protein, Hsp70, is reported to return to normal levels of expression shortly after heat stress. We......Heat-induced hormesis, i.e. the beneficial effect of mild heat-induced stress, increases the average lifespan of many organisms. This effect, which depends on the heat shock factor, decreases the log mortality rate weeks after the stress has ceased. To identify candidate genes that mediate...... conclude that the heat shock response, and Hsp70 in particular, may be central to the heat-induced increase in the average lifespan in flies that are exposed to mild heat stress early in life....

  4. Heat transfer and wall temperature effects in shock wave turbulent boundary layer interactions

    Science.gov (United States)

    Bernardini, M.; Asproulias, I.; Larsson, J.; Pirozzoli, S.; Grasso, F.

    2016-12-01

    Direct numerical simulations are carried out to investigate the effect of the wall temperature on the behavior of oblique shock wave turbulent boundary layer interactions at free-stream Mach number 2.28 and shock angle of the wedge generator φ =8∘ . Five values of the wall-to-recovery-temperature ratio (Tw/Tr ) are considered, corresponding to cold, adiabatic, and hot wall thermal conditions. We show that the main effect of cooling is to decrease the characteristic scales of the interaction in terms of upstream influence and extent of the separation bubble. The opposite behavior is observed in the case of heating, which produces a marked dilatation of the interaction region. The distribution of the Stanton number shows that a strong amplification of the heat transfer occurs across the interaction, with the maximum thermal and dynamic loads found for the case of the cold wall. The analysis reveals that the fluctuating heat flux exhibits a strong intermittent behavior, characterized by scattered spots with extremely high values compared to the mean. Furthermore, the analogy between momentum and heat transfer, typical of compressible, wall-bounded, equilibrium turbulent flows, does not apply for most of the interaction domain. The premultiplied spectra of the wall heat flux do not show any evidence of the influence of the low-frequency shock motion, and the primary mechanism for the generation of peak heating is found to be linked with the turbulence amplification in the interaction region.

  5. Heat shock and salicylic acid on postharvest preservation of organic strawberries

    Directory of Open Access Journals (Sweden)

    Sidiane Coltro

    2014-06-01

    Full Text Available Heat shock and salicylic acid have been studied on shelf-life extension of fruits. The benefits of these techniques have been related to their effect on inducing physiological defense responses against the oxidative stress and pathogen development. The objective of this study was to evaluate the effect of heat shock and salicylic acid on the postharvest preservation and contents of total phenolics, anthocyanins, ascorbic acid, fresh weight loss and microbiological quality of organic strawberries cv. Dover. Strawberries produced organically and stored at 5 ºC were subjected to heat shock (45 ºC ± 3 ºC for 3 h, application of salicylic acid (soaking in 2.0 mmol L-1 solution, heat shock in combination with salicylic acid and control. After treatment, the fruits were packed and stored in a climatic chamber at 5 ºC ± 2 ºC. At 1, 7 and 14 days, the experimental units were removed from refrigeration and kept at room temperature of approximately 20 ºC for two days. There was no effect of treatments on fresh weight loss, incidence of pathogens or chemical variations in strawberry fruits during the storage period. In natural conditions, organically grown strawberries remained in good condition for sale up to seven days of storage in all treatments.

  6. Associations among heat shock protein 70 genotype, forage system, and horn fly infestation of beef cattle

    Science.gov (United States)

    Horn fly infestations on beef cattle results in decreased productivity and challenges enterprise sustainability. Objective of this experiment was to determine the relationships among, cattle breed, heat shock protein 70 (Hsp70) genotype, and horn fly density. Angus (n = 20), Brahman (n = 17), and ...

  7. HIFI observations of warm gas in DR21 : Shock versus radiative heating

    NARCIS (Netherlands)

    Ossenkopf, Volker; Roellig, M.; Simon, R.; Schneider, N.; Okada, Y.; Stutzki, J.; Gerin, M.; Akyilmaz, M.; Beintema, D; Benz, A. O.; Berne, O.; Boulanger, F.; Bumble, B.; Coeur-Joly, O.; Dedes, C.; Diez-Gonzalez, M. C.; France, K.; Fuente, A.; Gallego, J. D.; Goicoechea, J. R.; Guesten, R.; Harris, A.; Higgins, R.; Jackson, B.; Jarchow, C.; Joblin, C.; Klein, T.; Kramer, C.; Lord, S.; Martin, P.; Martin-Pintado, J.; Mookerjea, B.; Neufeld, D. A.; Phillips, T.; Rizzo, J. R.; van der Tak, F. F. S.; Teyssier, D.; Yorke, H.

    2010-01-01

    Context. The molecular gas in the DR21 massive star formation region is known to be affected by the strong UV field from the central star cluster and by a fast outflow creating a bright shock. The relative contribution of both heating mechanisms is the matter of a long debate. Aims. By better sampli

  8. Heat-shock protein ClpL/HSP100 increases penicillin tolerance in Streptococcus pneumoniae.

    Science.gov (United States)

    Tran, Thao Dang-Hien; Kwon, Hyog-Young; Kim, Eun-Hye; Kim, Ki-Woo; Briles, David E; Pyo, Suhkneung; Rhee, Dong-Kwon

    2011-01-01

    Penicillin resistance and tolerance has been an increasing threat to the treatment of pneumococcal pneumoniae. However, no penicillin tolerance-related genes have been claimed. Here we show that a major heat shock protein ClpL/HSP100 could modulate the expression of a cell wall synthesis enzyme PBP2x, and subsequently increase cell wall thickness and penicillin tolerance in Streptococus pneumoniae.

  9. Heat Shock Factor 1: From Fire Chief to Crowd-Control Specialist.

    Science.gov (United States)

    Triandafillou, Catherine G; Drummond, D Allan

    2016-07-07

    HSF1 is the supposed master regulator of the heat shock response. In this issue of Molecular Cell, Solís et al. reveal that it has a much narrower job description: organizing a small team of molecular chaperones that keep the proteome moving.

  10. Dietary heme adversely affects experimental colitis in rats, despite heat-shock protein induction

    NARCIS (Netherlands)

    Schepens, Marloes A. A.; Vink, Carolien; Schonewille, Arjan J.; Dijkstra, Gerard; van der Meer, Roelof; Bovee-Oudenhoven, Ingeborg M. J.

    2011-01-01

    Objective: Research on dietary modulation of inflammatory bowel disease is in its infancy. Dietary heme, mimicking red meat, is cytotoxic to colonic epithelium and thus may aggravate colitis. Alternatively, heme-induced colonic stress might also result in potential protective heat-shock proteins (HS

  11. Periodic heat shock accelerated the chondrogenic differentiation of human mesenchymal stem cells in pellet culture.

    Directory of Open Access Journals (Sweden)

    Jing Chen

    Full Text Available Osteoarthritis (OA is one of diseases that seriously affect elderly people's quality of life. Human mesenchymal stem cells (hMSCs offer a potential promise for the joint repair in OA patients. However, chondrogenic differentiation from hMSCs in vitro takes a long time (∼ 6 weeks and differentiated cells are still not as functionally mature as primary isolated chondrocytes, though chemical stimulations and mechanical loading have been intensively studied to enhance the hMSC differentiation. On the other hand, thermal stimulations of hMSC chondrogenesis have not been well explored. In this study, the direct effects of mild heat shock (HS on the differentiation of hMSCs into chondrocytes in 3D pellet culture were investigated. Periodic HS at 41 °C for 1 hr significantly increased sulfated glycosaminoglycan in 3D pellet culture at Day 10 of chondrogenesis. Immunohistochemical and Western Blot analyses revealed an increased expression of collagen type II and aggrecan in heat-shocked pellets than non heat-shocked pellets on Day 17 of chondrogenesis. In addition, HS also upregulated the expression of collagen type I and X as well as heat shock protein 70 on Day 17 and 24 of differentiation. These results demonstrate that HS accelerated the chondrogenic differentiation of hMSCs and induced an early maturation of chondrocytes differentiated from hMSCs. The results of this study will guide the design of future protocols using thermal treatments to facilitate cartilage regeneration with human mesenchymal stem cells.

  12. A new case of multiple mitochondrial enzyme deficiencies with decreased amount of heat shock protein 60

    NARCIS (Netherlands)

    Briones, P; Vilaseca, MA; Ribes, A; Vernet, A; Lluch, M; Cusi, [No Value; Huckriede, A; Agsteribbe, E

    1997-01-01

    Heat shock protein 60 (hsp60) is a mitochondrial matrix protein involved in the folding and correct assembly of polypeptides into complex mitochondrial enzymes. Its deficiency has recently been described as the most likely primary cause of congenital lactic acidaemia with multiple mitochondrial enzy

  13. Management of the endoplasmic reticulum stress by activation of the heat shock response in yeast

    DEFF Research Database (Denmark)

    Hou, Jin; Tang, Hongting; Liu, Zihe

    2014-01-01

    In yeast Saccharomyces cerevisiae, accumulation of misfolded proteins in the endoplasmic reticulum (ER) causes ER stress and activates the unfolded protein response (UPR), which is mediated by Hac1p. The heat shock response (HSR) mediated by Hsf1p, mainly regulates cytosolic processes and protects...

  14. Identification of genes specifically expressed during heat shock treatment in Aedes aegypti

    Science.gov (United States)

    Temperature is important for mosquito development and physiological response. Several genes of heat shock protein (HSP) families are known to be expressed in mosquitoes and may be crucial in responding to stress induced by elevated temperature. Suppression subtractive hybridization (SSH) was used to...

  15. The role of the heat shock response in the cytoprotection of the intestinal epithelium

    NARCIS (Netherlands)

    Malago, Joshua Joseph

    2003-01-01

    Under normal conditions, the intestinal epithelial cells produce constitutive amount of heat shock proteins (Hsps) that are elevated following stressful stimuli. As the intestine is constantly exposed to variety of agents like diet, normal flora, infectious microorganisms, chemicals, and immune medi

  16. The growing world of small heat shock proteins : from structure to functions

    NARCIS (Netherlands)

    Carra, Serena; Alberti, Simon; Arrigo, Patrick A; Benesch, Justin L; Benjamin, Ivor J; Boelens, Wilbert; Bartelt-Kirbach, Britta; Brundel, Bianca J J M; Buchner, Johannes; Bukau, Bernd; Carver, John A; Ecroyd, Heath; Emanuelsson, Cecilia; Finet, Stephanie; Golenhofen, Nikola; Goloubinoff, Pierre; Gusev, Nikolai; Haslbeck, Martin; Hightower, Lawrence E; Kampinga, Harm H; Klevit, Rachel E; Liberek, Krzysztof; Mchaourab, Hassane S; McMenimen, Kathryn A; Poletti, Angelo; Quinlan, Roy; Strelkov, Sergei V; Toth, Melinda E; Vierling, Elizabeth; Tanguay, Robert M

    2017-01-01

    Small heat shock proteins (sHSPs) are present in all kingdoms of life and play fundamental roles in cell biology. sHSPs are key components of the cellular protein quality control system, acting as the first line of defense against conditions that affect protein homeostasis and proteome stability,

  17. Accumulation of Stable Full-Length Circular Group I Intron RNAs during Heat-Shock

    DEFF Research Database (Denmark)

    Andersen, Kasper L.; Beckert, Bertrand; Masquida, Benoit;

    2016-01-01

    the copy number of circular intron RNA from the myxomycete Didymium iridis. In exponentially growing amoebae, the circular introns are nuclear and found in 70 copies per cell. During heat-shock, the circular form is up-regulated to more than 500 copies per cell. The intron harbours two ribozymes that have...

  18. The declined phosphorylation of Heat shock protein 27 in rat cardiac muscle after hindlimb unloading

    Science.gov (United States)

    Yuan, Ming; Jiang, Shizhong; Li, Zhili; Yuan, Min; Ting, Li; Ying, Zhang; Wang, Desheng

    2009-07-01

    Hindlimb unloading can induce the cardiac atrophy and diminished cardiac function, however, the mechanisms responsible for which remain elusive. The chronic volume unloading of heart, which decreases the local mechanical stress, may lead to cardiac atrophy after hindlimb unloading. Many studies showed that integrin signaling, p38 MAPK, Heat shock protein 27 and cytoskeleton involved in the hypertrophic growth induced by mechanical stress. However, the mechanisms responsible for cardiac atrophy after hindlimb unloading are still unclear. In this study, we used the tail-suspended, hindlimb unloading rat model to simulate the effects of microgravity. Western blot analysis was used to detect the protein expression of Heat shock protein 27, focal adhesion kinase, p38 MAPK and their phosphorylation levels in rat cardiac muscle after 14d hindlimb unloading. The results showed that the phosphorylation levels of both Heat shock protein 27 and p38 MAPK were decreased significantly in rat cardiac muscle after hindlimb unloading. However, the phosphorylation level of focal adhesion kinase was not decreased significantly. The results suggested that Heat shock protein 27, the downstream of p38 MAPK, might play a critical role in the cardiac atrophy in response to simulated microgravity induced by hindlimb unloading.

  19. Derivation of Varying Specific Heat Gasdynamic Functions,Normal Shock Analytical Solution and its Improvements

    Institute of Scientific and Technical Information of China (English)

    TsuiChih-Ya

    1992-01-01

    A set of new gasdynamic functions with varying specific heat are deriveo for the first time.An original analytical solution of normal shock waves is owrked out therewith.This solution is thereafter further improved by not involving total temperature,Illustrative examples of comparison are given,including also some approximate solutions to show the orders of their errors.

  20. Dietary heme adversely affects experimental colitis in rats, despite heat-shock protein induction

    NARCIS (Netherlands)

    Schepens, Marloes A. A.; Vink, Carolien; Schonewille, Arjan J.; Dijkstra, Gerard; van der Meer, Roelof; Bovee-Oudenhoven, Ingeborg M. J.

    Objective: Research on dietary modulation of inflammatory bowel disease is in its infancy. Dietary heme, mimicking red meat, is cytotoxic to colonic epithelium and thus may aggravate colitis. Alternatively, heme-induced colonic stress might also result in potential protective heat-shock proteins

  1. Accumulation of Stable Full-Length Circular Group I Intron RNAs during Heat-Shock

    DEFF Research Database (Denmark)

    Andersen, Kasper L.; Beckert, Bertrand; Masquida, Benoit

    2016-01-01

    the copy number of circular intron RNA from the myxomycete Didymium iridis. In exponentially growing amoebae, the circular introns are nuclear and found in 70 copies per cell. During heat-shock, the circular form is up-regulated to more than 500 copies per cell. The intron harbours two ribozymes that have...

  2. Expressed sequence tags from heat-shocked seagrass Zostera noltii (Hornemann) from its southern distribution range

    NARCIS (Netherlands)

    Massa, Sonia I.; Pearson, Gareth A.; Aires, Tania; Kube, Michael; Olsen, Jeanine L.; Reinhardt, Richard; Serrao, Ester A.; Arnaud-Haond, Sophie

    2011-01-01

    Predicted global climate change threatens the distributional ranges of species worldwide. We identified genes expressed in the intertidal seagrass Zostera midi during recovery from a simulated low tide heat-shock exposure. Five Expressed Sequence Tag (EST) libraries were compared, corresponding to f

  3. Functional characterization of the small heat shock protein Hsp12p from Candida albicans.

    Directory of Open Access Journals (Sweden)

    Man-Shun Fu

    Full Text Available Hsp12p is considered to be a small heat shock protein and conserved among fungal species. To investigate the expression of this heat shock protein in the fungal pathogen Candida albicans we developed an anti-CaHsp12p antibody. We show that this protein is induced during stationary phase growth and under stress conditions including heat shock, osmotic, oxidative and heavy metal stress. Furthermore, we find that CaHsp12p expression is influenced by the quorum sensing molecule farnesol, the change of CO(2 concentration and pH. Notably we show that the key transcription factor Efg1p acts as a positive regulator of CaHsp12p in response to heat shock and oxidative stress and demonstrate that CaHsp12p expression is additionally modulated by Hog1p and the cAMP-PKA signaling pathway. To study the function of Hsp12p in C. albicans we generated a null mutant, in which all four CaHSP12 genes have been deleted. Phenotypic analysis of the strain shows that CaHSP12 is not essential for stress resistance, morphogenesis or virulence when tested in a Drosophila model of infection. However, when overexpressed, CaHSP12 significantly enhanced cell-cell adhesion, germ tube formation and susceptibility to azole antifungal agents whilst desensitizing C. albicans to the quorum sensing molecule farnesol.

  4. 热休克蛋白70%Heat shock protein70

    Institute of Scientific and Technical Information of China (English)

    叶春; 王瑞元; 何执静

    2001-01-01

    The heat shock response is a common cellular reaction to external stressers.A characteristic set of proteins is synthesized shortly after the organism is exposed to stress.Heat shock protein 70 family are the most strongly induced heat shock proteins.They are also called stress protein or molecular chaperones.They carry out important cellular functions,such as molecular chaperones,cellular protection.%热休克蛋白(HSP heat shock protein)是应激后细胞内优先合成的一组蛋白质,又称为应激蛋白(CSP,stress protein)或分子伴侣(chaperones)。其中HSP70它具有重要的细胞功能,如细胞保护作用、分子伴侣及抗氧化等。文章重点介绍HSP70的功能、结构、调节及与运动之间的相互影响。

  5. Genetic responses of the marine copepod Acartia tonsa (Dana) to heat shock and epibiont infestation

    DEFF Research Database (Denmark)

    Petkeviciute, Egle; Kania, Per Walter; Skovgaard, Alf

    2015-01-01

    Expression of stress-related genes was investigated in the marine copepod Acartia tonsa in relation to heat shock at two different salinities (10 and 32‰), and it was furthermore investigated whether experimentally induced epibiont infestation led to elevated expression of stress-related genes...

  6. Dynamics of the full length and mutated heat shock factor 1 in human cells.

    Directory of Open Access Journals (Sweden)

    Gaëtan Herbomel

    Full Text Available Heat shock factor 1 is the key transcription factor of the heat shock response. Its function is to protect the cell against the deleterious effects of stress. Upon stress, HSF1 binds to and transcribes hsp genes and repeated satellite III (sat III sequences present at the 9q12 locus. HSF1 binding to pericentric sat III sequences forms structures known as nuclear stress bodies (nSBs. nSBs represent a natural amplification of RNA pol II dependent transcription sites. Dynamics of HSF1 and of deletion mutants were studied in living cells using multi-confocal Fluorescence Correlation Spectroscopy (mFCS and Fluorescence Recovery After Photobleaching (FRAP. In this paper, we show that HSF1 dynamics modifications upon heat shock result from both formation of high molecular weight complexes and increased HSF1 interactions with chromatin. These interactions involve both DNA binding with Heat Shock Element (HSE and sat III sequences and a more transient sequence-independent binding likely corresponding to a search for more specific targets. We find that the trimerization domain is required for low affinity interactions with chromatin while the DNA binding domain is required for site-specific interactions of HSF1 with DNA.

  7. Genetic responses of the marine copepod Acartia tonsa (Dana) to heat shock and epibiont infestation

    DEFF Research Database (Denmark)

    Petkeviciute, Egle; Kania, Per Walter; Skovgaard, Alf

    2015-01-01

    Expression of stress-related genes was investigated in the marine copepod Acartia tonsa in relation to heat shock at two different salinities (10 and 32‰), and it was furthermore investigated whether experimentally induced epibiont infestation led to elevated expression of stress-related genes. E...

  8. Heat Shock Protein Induction in Human Cells by CO2 Laser Irradiation

    Science.gov (United States)

    1993-06-14

    Boorstein W. A review of the role of 70 kD heat shock proteins in protein translocation across membranes. Antonie Van Leeuwenhoek 1990:58:137-46. 32...1991;65:363-366. 55. Young DB. Stress proteins and the immune response. Antonie Van Leeuwenhoek 1990;58:203-208. 56. Craig EA, Kramer J, Kosic-Smithers

  9. The central role of heat shock factor 1 in synaptic fidelity and memory consolidation.

    Science.gov (United States)

    Hooper, Philip L; Durham, Heather D; Török, Zsolt; Hooper, Paul L; Crul, Tim; Vígh, László

    2016-09-01

    Networks of neuronal synapses are the fundamental basis for making and retaining memory. Reduced synapse number and quality correlates with loss of memory in dementia. Heat shock factor 1 (HSF1), the major transcription factor regulating expression of heat shock genes, plays a central role in proteostasis, in establishing and sustaining synaptic fidelity and function, and in memory consolidation. Support for this thesis is based on these observations: (1) heat shock induces improvements in synapse integrity and memory consolidation; (2) synaptic depolarization activates HSF1; (3) activation of HSF1 alone (independent of the canonical heat shock response) augments formation of essential synaptic elements-neuroligands, vesicle transport, synaptic scaffolding proteins, lipid rafts, synaptic spines, and axodendritic synapses; (4) HSF1 coalesces and activates memory receptors in the post-synaptic dendritic spine; (5) huntingtin or α-synuclein accumulation lowers HSF1 while HSF1 lowers huntingtin and α-synuclein aggregation-a potential vicious cycle; and (6) HSF1 agonists (including physical activity) can improve cognitive function in dementia models. Thus, via direct gene expression of synaptic elements, production of HSPs that assure high protein fidelity, and activation of other neuroprotective signaling pathways, HSF1 agonists could provide breakthrough therapy for dementia-associated disease.

  10. Uncertainty quantification of bacterial aerosol neutralization in shock heated gases

    Science.gov (United States)

    Schulz, J. C.; Gottiparthi, K. C.; Menon, S.

    2015-01-01

    A potential method for the neutralization of bacterial endospores is the use of explosive charges since the high thermal and mechanical stresses in the post-detonation flow are thought to be sufficient in reducing the endospore survivability to levels that pose no significant health threat. While several experiments have attempted to quantify endospore survivability by emulating such environments in shock tube configurations, numerical simulations are necessary to provide information in scenarios where experimental data are difficult to obtain. Since such numerical predictions require complex, multi-physics models, significant uncertainties could be present. This work investigates the uncertainty in determining the endospore survivability from using a reduced order model based on a critical endospore temperature. Understanding the uncertainty in such a model is necessary in quantifying the variability in predictions using large-scale, realistic simulations of bacterial endospore neutralization by explosive charges. This work extends the analysis of previous large-scale simulations of endospore neutralization [Gottiparthi et al. in (Shock Waves, 2014. doi:10.1007/s00193-014-0504-9)] by focusing on the uncertainty quantification of predicting endospore neutralization. For a given initial mass distribution of the bacterial endospore aerosol, predictions of the intact endospore percentage using nominal values of the input parameters match the experimental data well. The uncertainty in these predictions are then investigated using the Dempster-Shafer theory of evidence and polynomial chaos expansion. The studies show that the endospore survivability is governed largely by the endospore's mass distribution and their exposure or residence time at the elevated temperatures and pressures. Deviations from the nominal predictions can be as much as 20-30 % in the intermediate temperature ranges. At high temperatures, i.e., strong shocks, which are of the most interest, the

  11. Heat shock modulates the subcellular localization, stability, and activity of HIPK2

    Energy Technology Data Exchange (ETDEWEB)

    Upadhyay, Mamta; Bhadauriya, Pratibha; Ganesh, Subramaniam, E-mail: sganesh@iitk.ac.in

    2016-04-15

    The homeodomain-interacting protein kinase-2 (HIPK2) is a highly conserved serine/threonine kinase and is involved in transcriptional regulation. HIPK2 is a highly unstable protein, and is kept at a low level under normal physiological conditions. However, exposure of cells to physiological stress – such as hypoxia, oxidative stress, or UV damage – is known to stabilize HIPK2, leading to the HIPK2-dependent activation of p53 and the cell death pathway. Therefore HIPK2 is also known as a stress kinase and as a stress-activated pro-apoptotic factor. We demonstrate here that exposure of cells to heat shock results in the stabilization of HIPK2 and the stabilization is mediated via K63-linked ubiquitination. Intriguingly, a sub-lethal heat shock (42 °C, 1 h) results in the cytoplasmic localization of HIPK2, while a lethal heat shock (45 °C, 1 h) results in its nuclear localization. Cells exposed to the lethal heat shock showed significantly higher levels of the p53 activity than those exposed to the sub-lethal thermal stress, suggesting that both the level and the nuclear localization are essential for the pro-apoptotic activity of HIPK2 and that the lethal heat shock could retain the HIPK2 in the nucleus to promote the cell death. Taken together our study underscores the importance of HIPK2 in stress mediated cell death, and that the HIPK2 is a generic stress kinase that gets activated by diverse set of physiological stressors.

  12. Teratogens induce a subset of small heat shock proteins in Drosophila primary embryonic cell cultures.

    Science.gov (United States)

    Buzin, C H; Bournias-Vardiabasis, N

    1984-01-01

    Drosophila embryonic cells placed into culture just after gastrulation differentiate in vitro over the next 24 hr. A number of drugs that are teratogenic in mammalian systems have been found to inhibit muscle or neuron differentiation (or both) in these developing cultures. We have examined, by two-dimensional gel electrophoresis, the effects of these drugs on protein synthesis in embryonic cells. For nine teratogens tested, cells treated for 20 hr with the drug show a dramatic induction of three proteins of about 20 kilodaltons, in addition to the normal proteins synthesized by untreated cells. Three teratogens as well as all eight nonteratogens tested did not show this induction. The induced proteins appear to be identical to three of the heat shock proteins (hsp 23, 22a, and 22b), as shown by electrophoretic mobilities and peptide mapping by partial proteolysis. A 37 degrees C heat shock of the embryonic cells produces the full complement of heat shock proteins, whereas drug-treated cells induce only the subset hsp 23, 22a, and 22b but not hsp 26 or 27. beta-Ecdysterone, the Drosophila molting hormone, also inhibits embryonic differentiation and induces hsp 23, 22a, and 22b, a partial subset of the heat shock proteins (hsp 22, 23, 26, and 27) induced by the hormone in imaginal discs and some Drosophila continuous cell lines. Dose-response studies of several drugs show a correlation between the degree of inhibition of differentiation and the level of induction of hsp 23, 22a, and 22b. The induction of heat shock proteins by drugs may reflect specific types of stress that can also give rise to teratogenesis. Images PMID:6588379

  13. Putative cis-regulatory elements associated with heat shock genes activated during excystation of Cryptosporidium parvum.

    Directory of Open Access Journals (Sweden)

    Benjamin Cohn

    Full Text Available BACKGROUND: Cryptosporidiosis is a ubiquitous infectious disease, caused by the protozoan parasites Cryptosporidium hominis and C. parvum, leading to acute, persistent and chronic diarrhea worldwide. Although the complications of this disease can be serious, even fatal, in immunocompromised patients of any age, they have also been found to lead to long term effects, including growth inhibition and impaired cognitive development, in infected immunocompetent children. The Cryptosporidium life cycle alternates between a dormant stage, the oocyst, and a highly replicative phase that includes both asexual vegetative stages as well as sexual stages, implying fine genetic regulatory mechanisms. The parasite is extremely difficult to study because it cannot be cultured in vitro and animal models are equally challenging. The recent publication of the genome sequence of C. hominis and C. parvum has, however, significantly advanced our understanding of the biology and pathogenesis of this parasite. METHODOLOGY/PRINCIPAL FINDINGS: Herein, our goal was to identify cis-regulatory elements associated with heat shock response in Cryptosporidium using a combination of in silico and real time RT-PCR strategies. Analysis with Gibbs-Sampling algorithms of upstream non-translated regions of twelve genes annotated as heat shock proteins in the Cryptosporidium genome identified a highly conserved over-represented sequence motif in eleven of them. RT-PCR analyses, described herein and also by others, show that these eleven genes bearing the putative element are induced concurrent with excystation of parasite oocysts via heat shock. CONCLUSIONS/SIGNIFICANCE: Our analyses suggest that occurrences of a motif identified in the upstream regions of the Cryptosporidium heat shock genes represent parts of the transcriptional apparatus and function as stress response elements that activate expression of these genes during excystation, and possibly at other stages in the life

  14. Limits of shock heating for the chromospheres of low-gravity stars

    Science.gov (United States)

    Gadelmavla, Diaa

    2016-07-01

    This work discusses theoretical limits of chromospheric heating by shock waves in stars with low surface gravity. The computations are self consistent, and based on waves generated in stellar convection zones. We employ the new finding of the mixing length parameter α = 1.8. The Ca~II~H+K and Mg~II~h+k fluxes are computed assuming partial redistribution (PRD). The results show the strong dependence of the number of formed shocks and their transmission through the atmosphere on the value of the surface gravity. For stars with solar gravity, heating by shock waves is very efficient, this efficiency decreases with decreasing the value of G. For fixed effective temperature and solar metallicity, the temperature of the chromosphere increase with increasing the stellar surface gravity. A linear correlation is found between the surface gravity and the number of transmitted shocks. The emitted Mg~II and Ca~II fluxes show also a linear dependance on G. It has been found that there is a clear threshold value of G where no shocks are formed. The theoretically computed basal Ca~II and Mg~II fluxes follow simple formulae as a function of stellar surface gravity.

  15. Induction of Heat Shock Protein 72 in RGCs of Rat Acute Glaucoma Model after Heat Stress or Zinc Administration

    Institute of Scientific and Technical Information of China (English)

    Guoping Qing; Xuanchu Duan; Youqin Jiang

    2004-01-01

    Purpose :To investigate the dynamics of heat shock protein 72 (HSP72) expression in retinal ganglion cells (RGCs) in rat model of acute glaucoma treated with heat stress or intraperitoneal injection of zinc sulfate.Methods: Twenty-seven male Wistar rats were used to make acute glaucoma models. Five others served as normal control. Acute glaucoma models were made by intracameral irrigation in the right eyes with balanced salt saline (BSS) at 102 mmHg for 2 hours. Nine model rats were killed at different intervals after intracameral irrigation without treatment, which served as damage control. Ten were treated with heat stress 40℃~42℃, and 8 were used for zinc sulfate administration 2 days posterior to intracameral irrigation.Treated model rats were sacrificed at designed intervals after treatment. Right eyes were enucleated immediately, and the retinas were dissected for Western blot.Results: No HSP72 was found in RGCs of normal Wistar rats. In damage control group,slight HSP72 was detected during 6~36 hours posterior to intracameral irrigation. HSP72was detected significantly expressed in RGCs of both heat shock group and zinc sulfate group. But the dynamics of HSP72 production were quite different in these two treated groups. In heat shock group, HSP72 appeared at the sixth hour after treatment, and increased gradually until its peak production emerged at the 48th hour. HSP72 vanished 8days later after treatment. In zinc sulfate group, HSP72 expression began 24 hours later after zinc administration, and reached its highest level at the 72th hour posterior to treatment. HSP72 expression then decreased slowly, and disappeared 21 days later after treatment.Conclusion:HSP72 can be induced in RGCs of rat acute glaucoma models with heat stress or zinc sulfate adddministration. But the dynamics of the HSP72 induction in those two groups were quite different. Eye Science 2004;20:30-33.

  16. Anti-Inflammatory Heat Shock Protein 70 Genes are Positively Associated with Human Survival

    DEFF Research Database (Denmark)

    Singh, Ripudaman; Kølvraa, Steen; Bross, Peter Gerd;

    2010-01-01

    with longevity. The involvement of heat shock protein 70 (Hsp70) in cellular maintenance and repair mechanisms, including its role as an anti-inflammatory protein, makes it a suitable candidate for studying such associations. We have studied the association of three single nucleotide polymorphisms, HSPA1A (-110A...... the opportunity to perform survival analysis on these subjects. Haplotype relative risk, and genotype relative risk were calculated to measure the effects of haplotypes and genotypes on human survival in a sex-specific manner. A significant association of HSPA1A-AA (RR=3.864; p=0.016) and HSPA1B-AA (RR=2.764; p=0...... observations from heat shock response (HSR) study where we had shown that after heat stimulation, mononuclear cells from the carriers of genotype HSPA1L-TT had better HSR than cells with the HSPA1L-CC genotype....

  17. Observation of extremely strong shock waves in solids launched by petawatt laser heating

    Science.gov (United States)

    Lancaster, K. L.; Robinson, A. P. L.; Pasley, J.; Hakel, P.; Ma, T.; Highbarger, K.; Beg, F. N.; Chen, S. N.; Daskalova, R. L.; Freeman, R. R.; Green, J. S.; Habara, H.; Jaanimagi, P.; Key, M. H.; King, J.; Kodama, R.; Krushelnick, K.; Nakamura, H.; Nakatsutsumi, M.; MacKinnon, A. J.; MacPhee, A. G.; Stephens, R. B.; Van Woerkom, L.; Norreys, P. A.

    2017-08-01

    Understanding hydrodynamic phenomena driven by fast electron heating is important for a range of applications including fast electron collimation schemes for fast ignition and the production and study of hot, dense matter. In this work, detailed numerical simulations modelling the heating, hydrodynamic evolution, and extreme ultra-violet (XUV) emission in combination with experimental XUV images indicate shock waves of exceptional strength (200 Mbar) launched due to rapid heating of materials via a petawatt laser. We discuss in detail the production of synthetic XUV images and how they assist us in interpreting experimental XUV images captured at 256 eV using a multi-layer spherical mirror.

  18. Spatial Structure and Collisionless Electron Heating in Balmer-dominated Shocks

    CERN Document Server

    van Adelsberg, Matthew; McCray, Richard; Raymond, John C

    2008-01-01

    Balmer-dominated shocks in supernova remnants (SNRs) produce strong hydrogen lines with a two-component profile composed of a narrow contribution from cold upstream hydrogen atoms, and a broad contribution from hydrogen atoms that have undergone charge transfer reactions with hot protons. Observations of emission lines from edge-wise shocks in SNRs can constrain the gas velocity and collisionless electron heating at the shock front. Downstream hydrogen atoms engage in charge transfer, excitation and ionization reactions, defining an interaction region called the shock transition zone, with characteristic width l_{zone} \\sim 10^{15} cm, for shock velocity v_s \\sim 1000 km s^{-1} and upstream density n_0 \\sim 1 cm^{-3}. The properties of hot hydrogen atoms undergoing charge transfer (called broad neutrals) are critical for accurately calculating the structure and radiation from the shock transition zone. This paper is the third in a series describing the kinetic, fluid and emission properties of Balmer-dominate...

  19. Heat-shock protein 70 expression in shrimp Fenneropenaeus chinensis during thermal and immune-challenged stress

    Institute of Scientific and Technical Information of China (English)

    GUO Zhenyu; JIAO Chuanzhen; XIANG Jianhai

    2004-01-01

    Using western immunoblotting, we obtained heat-shock protein 70 (HSP70) induction data and distribution in different tissues from shrimp Fenneropenaeus chinensis during thermal and immune-challenged stresses. This is probably the first report of the effects of various stressors on the expression of HSP70 in shrimp. HSP70 was prominently induced in hepatopancreas and gills, but not in muscle, eyestalk and hemolymph, when the shrimp were exposed to heat shock and Vibrio anguillavium-challenged stresses. Cold shock and WSSV treatment had no significant effects on the levels of HSP70 expression in all tissues examined. HSP70 induction was greatest after 2 h exposure to heat shock stress, which was elevated after acute heat shock exposure of 10℃ above ambient temperature.

  20. Heat shock inhibits. alpha. -amylase synthesis in barley aleurone without inhibiting the activity of endoplasmic reticulum marker enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Sticher, L.; Biswas, A.K.; Bush, D.S.; Jones, R.L. (Univ. of California, Berkeley (USA))

    1990-02-01

    The effects of heat shock on the synthesis of {alpha}-amylase and on the membranes of the endoplasmic reticulum (ER) of barley (Hordeum vulgare) aleurone were studied. Heat shock, imposed by raising the temperature of incubation from 25{degree}C to 40{degree}C for 3 hours, inhibits the accumulation of {alpha}-amylase and other proteins in the incubation medium of barley aleurone layers treated with gibberellic acid and Ca{sup 2+}. When ER is isolated from heat-shocked aleurone layers, less newly synthesized {alpha}-amylase is found associated with this membrane system. ER membranes, as indicated by the activities of NADH cytochrome c reductase and ATP-dependent Ca{sup 2+} transport, are not destroyed by heat stress, however. Although heat shock did not reduce the activity of ER membrane marker enzymes, it altered the buoyant density of these membranes. Whereas ER from control tissue showed a peak of marker enzyme activity at 27% to 28% sucrose (1.113-1.120 grams per cubic centimeter), ER from heat-shocked tissue peaked at 30% to 32% sucrose (1.127-1.137 grams per cubic centimeter). The synthesis of a group of proteins designated as heat-shock proteins (HSPs) was stimulated by heat shock. These HSPs were localized to different compartments of the aleurone cell. Several proteins ranging from 15 to 30 kilodaltons were found in the ER and the mitochondrial/plasma membrane fractions of heat-shocked cells, but none of the HSPs accumulated in the incubation medium of heat-shocked aleurone layers.

  1. Target heating due to the shock produced hot electrons in the shock ignition scheme

    Science.gov (United States)

    Rezaei, Somayeh; Farahbod, Amir Hossein; Jafari, Mohammad Jafar; Sobhanian, Samad

    2016-09-01

    Hot electrons are produced as a result of ignitor-corona interaction of the shock ignition scheme. In the present paper, penetration depth and energy deposition of such energetic electrons have been qualitatively discussed applying Monte Carlo simulations. Target real conditions for propagating hot electrons were taken from 1-D hydrodynamic simulations. It has been found that compressing target up to 10.4 ns helps to stop hot electrons at a proper distance thus, preventing fuel preheating. In addition, embedding hot electron energy source into the hydrodynamic code, changes of parameters p, ρ and ρR are calculated. Monoenergetic electron beams have been launched at different times of target compression. The simulation results indicate the creation of high ablation pressure as well as maximum shell areal density by a 50 keV monoenergetic electron beam with intensity 1 PW/cm2 irradiated on the compressed target at a proper time which indeed improves the implosion processes.

  2. ZERO DISSIPATION LIMIT OF THE COMPRESSIBLE HEAT-CONDUCTING NAVIER-STOKES EQUATIONS IN HE PRESENCE OF THE SHOCK

    Institute of Scientific and Technical Information of China (English)

    Wang Yi

    2008-01-01

    The zero dissipation limit of the compressible heat-conducting Navier-Stokes equations in the presence of the shock is investigated. It is shown that when the heat ε→ 0 (see (1.3)), if the solution of the corresponding Euler equations is piecewise smooth with shock wave satisfying the Lax entropy condition, then there exists a smooth solution to the Navier-Stokes equations, which converges to the piecewise smooth shock solution of the Euler equations away from the shock discontinuity at a rate of ε. The proof is given by a combination of the energy estimates and the matched asymptotic analysis introduced in [3].

  3. The chicken ubiquitin gene contains a heat shock promoter and expresses an unstable mRNA in heat-shocked cells.

    OpenAIRE

    Bond, U; Schlesinger, M J

    1986-01-01

    A chicken genomic library was screened to obtain genomic clones for ubiquitin genes. Two genes that differ in their genomic location and organization were identified. One gene, designated Ub I, contains four copies of the protein-coding sequence arranged in tandem, while the second gene, Ub II, contains three. The origin of the two major mRNAs that are induced after heat shock in chicken embryo fibroblasts was determined by generating DNA probes from the 5'-and 3'-noncoding regions of the two...

  4. An artificial HSE promoter for efficient and selective detection of heat shock pathway activity.

    Science.gov (United States)

    Ortner, Viktoria; Ludwig, Alfred; Riegel, Elisabeth; Dunzinger, Sarah; Czerny, Thomas

    2015-03-01

    Detection of cellular stress is of major importance for the survival of cells. During evolution, a network of stress pathways developed, with the heat shock (HS) response playing a major role. The key transcription factor mediating HS signalling activity in mammalian cells is the HS factor HSF1. When activated it binds to the heat shock elements (HSE) in the promoters of target genes like heat shock protein (HSP) genes. They are induced by HSF1 but in addition they integrate multiple signals from different stress pathways. Here, we developed an artificial promoter consisting only of HSEs and therefore selectively reacting to HSF-mediated pathway activation. The promoter is highly inducible but has an extreme low basal level. Direct comparison with the HSPA1A promoter activity indicates that heat-dependent expression can be fully recapitulated by isolated HSEs in human cells. Using this sensitive reporter, we measured the HS response for different temperatures and exposure times. In particular, long heat induction times of 1 or 2 h were compared with short heat durations down to 1 min, conditions typical for burn injuries. We found similar responses to both long and short heat durations but at completely different temperatures. Exposure times of 2 h result in pathway activation at 41 to 44 °C, whereas heat pulses of 1 min lead to a maximum HS response between 47 and 50 °C. The results suggest that the HS response is initiated by a combination of temperature and exposure time but not by a certain threshold temperature.

  5. Shock experiments on pre-heated alpha- and beta-quartz: 1. Optical and density data

    Science.gov (United States)

    Langenhorst, Falko; Deutsch, Alexander

    1994-07-01

    Discs of single crystal quartz, unheated, and pre-heated to 275 C and 540 C (i.e., alpha-quartz) and 630 C (i.e., beta-quartz) were experimentally shocked to pressures ranging from 20 to 40 GPa, with the shock front propagating parallel to either (10-10) or (0001). Refractive indices, density and the orientation of planar deformation features (PDFs) were determined on the recovered quartz samples. Refractive indices of pre-heated quartz are unaffected up to 25 GPa but density starts to decrease slightly up to this pressure. Above 25 GPa, pre-heating causes drastic variations: Refractive indices and birefringence of quartz shocked at ambient temperature decrease continuously, until complete isotropization is reached at 35 GPa. In quartz shocked at 630 C, refractivity drops discontinuously in the interval from 25 to 26 GPa, and complete transformation to diaplectic glass is reached at 26 GPa. Density follows the trends demonstrated by the optical parameters, with higher pre-shock temperatures yielding lower density at a given shock pressure. These results indicate that the threshold pressure for the onset of transformation to diaplectic quartz glass is largely temperature-invariant, lying at 25 GPa, whereas the pressure limit for complete transformation decreases with increasing pre-shock temperature from approximately equal 35 to approximately equal 26 GPa. Quartz shocked parallel to (0001) always has a higher density and refractivity than that shocked parallel to (10-10), indicating a significant influence of the structural anisotropy. This is also evident from the distribution of PDF orientations. Pressures greater than or equal 25 GPa cause, in quartz shocked parallel to (10-10), PDFs that are predominantly oriented parallel to set of (10-12) planes, while quartz shocked to the same pressures but parallel to (0001) contains almost exclusively PDFs parallel to set of (10-13) planes. PDF orientations in quartz shocked at ambient temperature parallel to (10-10) show

  6. Global Analysis of Heat Shock Response in Desulfovibrio vulgaris Hildenborough.

    Energy Technology Data Exchange (ETDEWEB)

    Chhabra, S.R.; He, Q.; Huang, K.H.; Gaucher, S.P.; Alm, E.J.; He,Z.; Hadi, M.Z.; Hazen, T.C.; Wall, J.D.; Zhou, J.; Arkin, A.P.; Singh, A.K.

    2005-09-16

    Desulfovibrio vulgaris Hildenborough belongs to a class ofsulfate-reducing bacteria (SRB) and is found ubiquitously in nature.Given the importance of SRB-mediated reduction for bioremediation ofmetal ion contaminants, ongoing research on D. vulgaris has been in thedirection of elucidating regulatory mechanisms for this organism under avariety of stress conditions. This work presents a global view of thisorganism's response to elevated growth temperature using whole-celltranscriptomics and proteomics tools. Transcriptional response (1.7-foldchange or greater; Z>1.5) ranged from 1,135 genes at 15 min to 1,463genes at 120 min for a temperature up-shift of 13oC from a growthtemperature of 37oC for this organism and suggested both direct andindirect modes of heat sensing. Clusters of orthologous group categoriesthat were significantly affected included posttranslationalmodifications; protein turnover and chaperones (up-regulated); energyproduction and conversion (down-regulated), nucleotide transport,metabolism (down-regulated), and translation; ribosomal structure; andbiogenesis (down-regulated). Analysis of the genome sequence revealed thepresence of features of both negative and positive regulation whichincluded the CIRCE element and promoter sequences corresponding to thealternate sigma factors ?32 and ?54. While mechanisms of heat shockcontrol for some genes appeared to coincide with those established forEscherichia coli and Bacillus subtilis, the presence of unique controlschemes for several other genes was also evident. Analysis of proteinexpression levels using differential in-gel electrophoresis suggestedgood agreement with transcriptional profiles of several heat shockproteins, including DnaK (DVU0811), HtpG (DVU2643), HtrA (DVU1468), andAhpC (DVU2247). The proteomics study also suggested the possibility ofposttranslational modifications in the chaperones DnaK, AhpC, GroES(DVU1977), and GroEL (DVU1976) and also several periplasmic ABCtransporters.

  7. Heat shock increases oxidative stress to modulate growth and physico-chemical attributes in diverse maize cultivars

    Science.gov (United States)

    Hussain, Iqbal; Ashraf, Muhammad Arslan; Rasheed, Rizwan; Iqbal, Muhammad; Ibrahim, Muhammad; Ashraf, Shamila

    2016-10-01

    The present investigation was conducted to appraise the physiochemical adjustments in contrasting maize cultivars, namely, PakAfgoi (tolerant) and EV-5098 (sensitive) subjected to heat shock. Seven-day-old seedlings were exposed to heat shock for different time intervals (1, 3, 6, 24, 48 and 72 h) and data for various physiochemical attributes determined to appraise time course changes in maize. After 72 h of heat shock, the plants were grown under normal conditions for 5 d and data for different growth attributes and photosynthetic pigments recorded. Exposure to heat shock reduced growth and photosynthetic pigments in maize cultivars. The plants exposed to heat shock for up to 3 h recovered growth and photosynthetic pigments when stress was relieved. A time course rise in the relative membrane permeability, hydrogen peroxide (H2O2) and malondialdehyde contents was recorded particularly in the EV-5098 indicating that heat shock-induced oxidative stress. Activities of different enzymatic antioxidants greatly altered due to heat shock. For instance, an increase in superoxide dismutase activity was recorded in both maize cultivars. The activity of ascorbate peroxidase was greater in Pak-Afgoi. However, the peroxidase and catalase activities were higher in plants of EV-5098. Heat shock caused a significant rise in the proline and decline in the total free amino acids. Overall, the performance of Pak-Afgoi was better in terms of having lesser oxidative damage and greater cellular levels of proline. The results suggested that oxidative stress indicators (relative membrane permeability, H2O2 and malondialdehyde) and proline can be used as markers for heat shock tolerant plants.

  8. Wind Observations of Wave Heating and/or Particle Energization at Supercritical Interplanetary Shocks

    Science.gov (United States)

    Wilson, Lynn Bruce, III; Szabo, Adam; Koval, Andriy; Cattell, Cynthia A.; Kellogg, Paul J.; Goetz, Keith; Breneman, Aaron; Kersten, Kris; Kasper, Justin C.; Pulupa, Marc

    2011-01-01

    We present the first observations at supercritical interplanetary shocks of large amplitude (> 100 mV/m pk-pk) solitary waves, approx.30 mV/m pk-pk waves exhibiting characteristics consistent with electron Bernstein waves, and > 20 nT pk-pk electromagnetic lower hybrid-like waves, with simultaneous evidence for wave heating and particle energization. The solitary waves and the Bernstein-like waves were likely due to instabilities driven by the free energy provided by reflected ions [Wilson III et al., 2010]. They were associated with strong particle heating in both the electrons and ions. We also show a case example of parallel electron energization and perpendicular ion heating due to a electromagnetic lower hybrid-like wave. Both studies provide the first experimental evidence of wave heating and/or particle energization at interplanetary shocks. Our experimental results, together with the results of recent Vlasov [Petkaki and Freeman, 2008] and PIC [Matsukyo and Scholer, 2006] simulations using realistic mass ratios provide new evidence to suggest that the importance of wave-particle dissipation at shocks may be greater than previously thought.

  9. The role of the membrane-initiated Heat Shock Response in cancer

    Directory of Open Access Journals (Sweden)

    Zohar eBromberg

    2016-04-01

    Full Text Available The heat shock response (HSR is a cellular response to diverse environmental and physiological stressors resulting in the induction of genes encoding molecular chaperones, proteases and other proteins that are essential for protection and recovery from cellular damage. Since different perturbations cause accumulation of misfolded proteins, cells frequently encounter fluctuations in the environment which alter proteostasis. Since tumor cells use their natural adaptive mechanism of coping with stress and misfolded proteins, in recent years, the proteostasis network became a promising target for anti-tumor therapy. The membrane is the first to be affected by heat shock and therefore may be the first one to sense heat shock. The membrane also connects between the extracellular and the intracellular signals. Hence, there is a cross talk between the HSR and the membranes since heat shock can induce changes in the fluidity of membranes, leading to membrane lipid remodeling that occurs in several diseases such as cancer. During the last decade, a new possible therapy has emerged in which an external molecule is used that could induce membrane lipid re-organization. Since at the moment there are very few substances that regulate the HSR effectively, an alternative way has been searched to modulate chaperone activities through the plasma membrane. Recently, we suggested that the use of the membrane Transient Receptor Potential Vanilloid-1 (TRPV1 modulators regulated the HSR in cancer cells. However, the primary targets of the signal transduction pathway are yet un-known. This review provides an overview of the current literature regarding the role of HSR in membrane remodeling in cancer since a deep understanding of the membrane biology in cancer and the membrane heat sensing pathway is essential to design novel efficient therapies.

  10. Small Heat Shock Proteins Can Release Light Dependence of Tobacco Seed during Germination1[OPEN

    Science.gov (United States)

    Koo, Hyun Jo; Park, Soo Min; Kim, Keun Pill; Suh, Mi Chung; Lee, Mi Ok; Lee, Seong-Kon; Xinli, Xia

    2015-01-01

    Small heat shock proteins (sHSPs) function as ATP-independent molecular chaperones, and although the production and function of sHSPs have often been described under heat stress, the expression and function of sHSPs in fundamental developmental processes, such as pollen and seed development, have also been confirmed. Seed germination involves the breaking of dormancy and the resumption of embryo growth that accompany global changes in transcription, translation, and metabolism. In many plants, germination is triggered simply by imbibition of water; however, different seeds require different conditions in addition to water. For small-seeded plants, like Arabidopsis (Arabidopsis thaliana), lettuce (Lactuca sativa), tomato (Solanum lycopersicum), and tobacco (Nicotiana tabacum), light is an important regulator of seed germination. The facts that sHSPs accumulate during seed development, sHSPs interact with various client proteins, and seed germination accompanies synthesis and/or activation of diverse proteins led us to investigate the role of sHSPs in seed germination, especially in the context of light dependence. In this study, we have built transgenic tobacco plants that ectopically express sHSP, and the effect was germination of the seeds in the dark. Administering heat shock to the seeds also resulted in the alleviation of light dependence during seed germination. Subcellular localization of ectopically expressed sHSP was mainly observed in the cytoplasm, whereas heat shock-induced sHSPs were transported to the nucleus. We hypothesize that ectopically expressed sHSPs in the cytoplasm led the status of cytoplasmic proteins involved in seed germination to function during germination without additional stimulus and that heat shock can be another signal that induces seed germination. PMID:25604531

  11. Small heat shock proteins can release light dependence of tobacco seed during germination.

    Science.gov (United States)

    Koo, Hyun Jo; Park, Soo Min; Kim, Keun Pill; Suh, Mi Chung; Lee, Mi Ok; Lee, Seong-Kon; Xinli, Xia; Hong, Choo Bong

    2015-03-01

    Small heat shock proteins (sHSPs) function as ATP-independent molecular chaperones, and although the production and function of sHSPs have often been described under heat stress, the expression and function of sHSPs in fundamental developmental processes, such as pollen and seed development, have also been confirmed. Seed germination involves the breaking of dormancy and the resumption of embryo growth that accompany global changes in transcription, translation, and metabolism. In many plants, germination is triggered simply by imbibition of water; however, different seeds require different conditions in addition to water. For small-seeded plants, like Arabidopsis (Arabidopsis thaliana), lettuce (Lactuca sativa), tomato (Solanum lycopersicum), and tobacco (Nicotiana tabacum), light is an important regulator of seed germination. The facts that sHSPs accumulate during seed development, sHSPs interact with various client proteins, and seed germination accompanies synthesis and/or activation of diverse proteins led us to investigate the role of sHSPs in seed germination, especially in the context of light dependence. In this study, we have built transgenic tobacco plants that ectopically express sHSP, and the effect was germination of the seeds in the dark. Administering heat shock to the seeds also resulted in the alleviation of light dependence during seed germination. Subcellular localization of ectopically expressed sHSP was mainly observed in the cytoplasm, whereas heat shock-induced sHSPs were transported to the nucleus. We hypothesize that ectopically expressed sHSPs in the cytoplasm led the status of cytoplasmic proteins involved in seed germination to function during germination without additional stimulus and that heat shock can be another signal that induces seed germination.

  12. More than mass proportional heating of heavy ions by supercritical collisionless shocks in the solar corona

    CERN Document Server

    Zimbardo, Gaetano

    2009-01-01

    We propose a new model for explaining the observations of more than mass proportional heating of heavy ions in the polar solar corona. We point out that a large number of small scale intermittent shock waves can be present in the solar corona. The energization mechanism is, essentially, the ion reflection off supercritical quasi-perpendicular collisionless shocks in the corona and the subsequent acceleration by the motional electric field ${\\bf E} = - (1/c) {\\bf V} \\times {\\bf B}$. The acceleration due to ${\\bf E}$ is perpendicular to the magnetic field, in agreement with observations, and is more than mass proportional with respect to protons, because the heavy ion orbit is mostly upstream of the quasi-perpendicular shock foot. The observed temperature ratios between O$^{5+}$ ions and protons in the polar corona, and between $\\alpha$ particles and protons in the solar wind are easily recovered.

  13. Heat shock-induced apoptosis in germ line cells of Triatoma infestans Klug

    Directory of Open Access Journals (Sweden)

    Maria Luiza S. Mello

    2000-06-01

    Full Text Available The survival of Triatoma infestans and of somatic cells from this species is affected by heat shock. In this study, we examined the cell death responses of male germ line cells from 5th instar nymphs 7 and 30 days after heat shock exposure (40ºC, 1 h. The preparations were stained by the Feulgen reaction and the TUNEL immunocytochemical assay. Apoptosis was elicited by heat shock, with positive TUNEL responses in spermatogonial chromatin and chromosomes, spermatids and sperm cells. Spermatogonia were most affected seven days after the shock whereas some spermatids and sperm cells exhibited DNA fragmentation only thirty days after heat shock. The rate of cell death varied among the cells. In some cases, cellular differentiation was unaffected by heat shock, with DNA fragmentation occurring towards the end of spermatogenesis.Uma vez que em Triatoma infestans a sobrevivência de células somáticas e dos próprios espécimes é afetada por choques de temperatura, foi estudada a indução de morte celular em células da linhagem germinativa masculina de ninfas de 5o. estadio 7 e 30 dias após choque de 1 h a 40ºC. Os preparados foram submetidos à reação de Feulgen e ao teste imunocitoquímico TUNEL. Foi encontrada apoptose induzida pelo choque de temperatura, sendo que respostas positivas ao TUNEL foram vistas na cromatina e em cromossomos de espermatogônias e em espermátides e espermatozóides. As espermatogônias foram afetadas principalmente 7 dias após o choque, enquanto algumas espermátides e espermatozóides exibiram fragmentação de DNA apenas 30 dias após o choque. Admite-se que a velocidade com a qual avança o processo de morte celular varie nessas células. Diferenciação celular não é impedida em parte das células afetadas, permitindo que a fragmentação de seu DNA ocorra mais tardiamente, inclusive no fim da espermatogênese.

  14. Shock

    Science.gov (United States)

    Shock can be caused by any condition that reduces blood flow, including: Heart problems (such as heart attack or heart failure ) Low blood volume (as with heavy bleeding or dehydration ) Changes in blood vessels (as with infection ...

  15. Shock-Wave Heating Model for Chondrule Formation: Prevention of Isotopic Fractionation

    CERN Document Server

    Miura, H; Miura, Hitoshi; Nakamoto, Taishi

    2006-01-01

    Chondrules are considered to have much information on dust particles and processes in the solar nebula. It is naturally expected that protoplanetary disks observed in present star forming regions have similar dust particles and processes, so study of chondrule formation may provide us great information on the formation of the planetary systems. Evaporation during chondrule melting may have resulted in depletion of volatile elements in chondrules. However, no evidence for a large degree of heavy-isotope enrichment has been reported in chondrules. In order to meet this observed constraint, the rapid heating rate at temperatures below the silicate solidus is required to suppress the isotopic fractionation. We have developed a new shock-wave heating model taking into account the radiative transfer of the dust thermal continuum emission and the line emission of gas molecules and calculated the thermal history of chondrules. We have found that optically-thin shock waves for the thermal continuum emission from dust ...

  16. Co-localization of the heat shock protein and human immunoglobulin G in hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    DUAN Chun-guang; LIU Yan-fang; LI Kai-nan; YU Lu; CUI Ji-hong; LI Jing; YANG Shou-jing

    2005-01-01

    @@ Elevated levels of serum immunoglobulin observed in patients with cancers of epithelial origin, including carcinomas of breast, colon, and liver1,2 have been interpreted as humoral responses of host to cancer growth.3 Recently, Qiu et al4 described in detail that human cancers of epithelial origin, including carcinomas of breast, colon, liver, lung, established epithelial cancer lines, produce immunoglobulin G (IgG) in their cytoplasm. Under normal conditions, heat shock proteins (HSPs) have multiple cellular functions, such as folding and translocating newly synthesized proteins. When a cell is injured or under stress, HSPs refold damaged protein or facilitate degradation of proteins. In most cancers, heat shock proteins can capture tumour specific peptide to inhibit the growth of cancer. This study demonstrated that human IgG and HSPs are co-localized in hepatocellular carcinoma.

  17. Heat Shock Followed by Priming Increases the Quality of Agropyron elongatum Seeds under Accelerated Ageing

    Directory of Open Access Journals (Sweden)

    Malihe AKBARPOUR BAHREH

    2014-06-01

    Full Text Available The present study was carried out to examine the possibilities of obtaining primed seeds that maintain high germination quality and the same longevity as the untreated seeds. For Tall wheatgrass tested, we found that the desired longevity could be obtained by keeping the seeds under heat shock for a period of several hours, after a priming treatment. Decreasing germination and seedling vigour in BAP 25 and 50 ppm, for 24 priming, did not happen again due to such a treatment. In addition, following priming, heat shock affects the initial quality of primed seeds in some treatments. Optimal temperature was strongly duration dependent. The method was applied to obtain primed seeds without the loss of storability, which is similar to those procedures used to induce desiccation tolerance in germinated seeds and acquire thermo tolerance in plant vegetative tissues.

  18. Oligomers of heat-shock proteins: Structures that don't imply function

    CERN Document Server

    Jacobs, William M; Frenkel, Daan

    2015-01-01

    Most proteins must remain soluble in the cytosol in order to perform their biological functions. To protect against undesired protein aggregation, living cells maintain a population of molecular chaperones that ensure the solubility of the proteome. Here we report simulations of a lattice model of interacting proteins to understand how low concentrations of passive molecular chaperones, such as small heat-shock proteins, suppress thermodynamic instabilities in protein solutions. Given fixed concentrations of chaperones and client proteins, the solubility of the proteome can be increased by tuning the chaperone--client binding strength. Surprisingly, we find that the binding strength that optimizes solubility while preventing irreversible chaperone binding also promotes the formation of weakly bound chaperone oligomers, although the presence of these oligomers does not significantly affect the thermodynamic stability of the solution. Such oligomers are commonly observed in experiments on small heat-shock prote...

  19. In Vivo Profiling Reveals a Competent Heat Shock Response in Adult Neurons: Implications for Neurodegenerative Disorders.

    Directory of Open Access Journals (Sweden)

    Alisia Carnemolla

    Full Text Available The heat shock response (HSR is the main pathway used by cells to counteract proteotoxicity. The inability of differentiated neurons to induce an HSR has been documented in primary neuronal cultures and has been proposed to play a critical role in ageing and neurodegeneration. However, this accepted dogma has not been demonstrated in vivo. We used BAC transgenic mice generated by the Gene Expression Nervous System Atlas project to investigate the capacity of striatal medium sized spiny neurons to induce an HSR as compared to that of astrocytes and oligodendrocytes. We found that all cell populations were competent to induce an HSR upon HSP90 inhibition. We also show the presence and relative abundance of heat shock-related genes and proteins in these striatal cell populations. The identification of a competent HSR in adult neurons supports the development of therapeutics that target the HSR pathway as treatments for neurodegenerative disorders.

  20. SWATH-MS dataset of heat-shock treated Drosophila melanogaster embryos.

    Science.gov (United States)

    Fabre, Bertrand; Korona, Dagmara; Nightingale, Daniel J H; Russell, Steven; Lilley, Kathryn S

    2016-12-01

    Data independent acquisition (DIA) has emerged as a promising mass spectrometry based approach, combining the advantages of shotgun and targeted proteomics. Here we applied a DIA approach (termed SWATH) to monitor the dynamics of the Drosophila melanogaster embryonic proteome upon heat-shock treatment. Embryos were incubated for 0.5, 1 or 3 h at 37 °C to induce heat-shock or maintained at 25 °C. The present dataset contains SWATH files acquired on a Sciex Triple-TOF 6600. A spectral library built in-house was used to analyse these data and led to the quantification of more than 2500 proteins at every timepoint. The files presented here are permanent digital maps and can be reanalysed to search for new questions. The data have been deposited with the ProteomeXchange Consortium with the dataset identifier PRIDE: PXD004753.

  1. SWATH-MS dataset of heat-shock treated Drosophila melanogaster embryos

    Directory of Open Access Journals (Sweden)

    Bertrand Fabre

    2016-12-01

    Full Text Available Data independent acquisition (DIA has emerged as a promising mass spectrometry based approach, combining the advantages of shotgun and targeted proteomics. Here we applied a DIA approach (termed SWATH to monitor the dynamics of the Drosophila melanogaster embryonic proteome upon heat-shock treatment. Embryos were incubated for 0.5, 1 or 3 h at 37 °C to induce heat-shock or maintained at 25 °C. The present dataset contains SWATH files acquired on a Sciex Triple-TOF 6600. A spectral library built in-house was used to analyse these data and led to the quantification of more than 2500 proteins at every timepoint. The files presented here are permanent digital maps and can be reanalysed to search for new questions. The data have been deposited with the ProteomeXchange Consortium with the dataset identifier PRIDE: PXD004753.

  2. Heat shock protein 70 down-regulates the production of toll-like receptor-induced pro-inflammatory cytokines by a heat shock factor-1/constitutive heat shock element-binding factor-dependent mechanism.

    Science.gov (United States)

    Ferat-Osorio, Eduardo; Sánchez-Anaya, Aldair; Gutiérrez-Mendoza, Mireille; Boscó-Gárate, Ilka; Wong-Baeza, Isabel; Pastelin-Palacios, Rodolfo; Pedraza-Alva, Gustavo; Bonifaz, Laura C; Cortés-Reynosa, Pedro; Pérez-Salazar, Eduardo; Arriaga-Pizano, Lourdes; López-Macías, Constantino; Rosenstein, Yvonne; Isibasi, Armando

    2014-01-01

    Heat shock protein 70 (Hsp70) is an intracellular chaperone protein with regulatory and cytoprotective functions. Hsp70 can also be found in the extracellular milieu, as a result of active secretion or passive release from damaged cells. The role of extracellular Hsp70 is not fully understood. Some studies report that it activates monocytes, macrophages and dendritic cells through innate immune receptors (such as Toll-like receptors, TLRs), while others report that Hsp70 is a negative regulator of the inflammatory response. In order to address this apparent inconsistency, in this study we evaluated the response of human monocytes to a highly purified recombinant Hsp70. Human peripheral blood monocytes were stimulated with Hsp70, alone or in combination with TLR agonists. Cytokines were quantified in culture supernatants, their mRNAs were measured by RT-PCR, and the binding of transcription factors was evaluated by electrophoretic mobility shift assay (EMSA). Kruskal-Wallis test or one-way or two-way ANOVA were used to analyze the data. The addition of Hsp70 to TLR-activated monocytes down-regulated TNF-α as well as IL-6 levels. This effect was independent of a physical interaction between Hsp70 and TLR agonists; instead it resulted of changes at the TNF-α gene expression level. The decrease in TNF-α expression correlated with the binding of HSF-1 (heat shock transcription factor 1, a transcription factor activated in response to Hsp70) and CHBF (constitutive HSE-binding factor) to the TNF-α gene promoter. Extracellular Hsp70 negatively regulates the production of pro-inflammatory cytokines of monocytes exposed to TLR agonists and contributes to dampen the inflammatory response.

  3. Heat shock increases conjugation efficiency in Clostridium difficile.

    Science.gov (United States)

    Kirk, Joseph A; Fagan, Robert P

    2016-12-01

    Clostridium difficile infection has increased in incidence and severity over the past decade, and poses a unique threat to human health. However, genetic manipulation of C. difficile remains in its infancy and the bacterium remains relatively poorly characterised. Low-efficiency conjugation is currently the only available method for transfer of plasmid DNA into C. difficile. This is practically limiting and has slowed progress in understanding this important pathogen. Conjugation efficiency varies widely between strains, with important clinically relevant strains such as R20291 being particularly refractory to plasmid transfer. Here we present an optimised conjugation method in which the recipient C. difficile is heat treated prior to conjugation. This significantly improves conjugation efficiency in all C. difficile strains tested including R20291. Conjugation efficiency was also affected by the choice of media on which conjugations were performed, with standard BHI media giving most transconjugant recovery. Using our optimised method greatly increased the ease with which the chromosome of R20291 could be precisely manipulated by homologous recombination. Our method improves on current conjugation protocols and will help speed genetic manipulation of strains otherwise difficult to work with. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Blood heat shock proteins evoked by some Salmonella strains infection in ducks.

    Science.gov (United States)

    Osman, Kamelia; Ibrahim, Ihab; Yousef, Ashgan; Nabil, Tanios; Nayerah, Alatfeehy

    2012-05-01

    Bacterial heat-shock response is a global regulatory system required for effective adaptation to changes (stress) in the environment. An in vitro study was conducted to investigate the impact of a sublethal temperature (42°C) on heat shock protein (HSP) expression in 6 Salmonella strains (Salmonella Enteritidis, S. Typhimurium, S. Virchow, S. Shubra, S. Haifa and S. Eingedi). The 6 Salmonella strains were isolated from the tissues of ducklings that had died from avian salmonellosis. To determine the induction of HSP in the 6 Salmonella strains, they were exposed to the selected temperature level for 24 h and further kept for 48 h at culturing condition of 42°C. Growth under a sublethal temperature of 42°C increased the expression of several proteins of Salmonella, including a 63 kDa protein in addition to the generation and/or overexpression of 143 proteins which were specific to heat shock, concurrent to this acquired thermotolerance. The 6 Salmonella strains responded to 24 h of thermal stress at an elevated temperature 42°C by synthesizing different heat shock proteins (HSP) with molecular weights ranging between 13.62 and 96.61 kDa. At 48 h, the 6 Salmonella strains synthesized different HSPs with molecular weights ranging between 14.53 and 103.43 kDa. It follows that salmonellae would produce HSPs during the course of the infectious process. Salmonellosis produced several proteins after 24 and 48 h of infection. Seven of these proteins (100, 80, 60, 40, 30, 20 and 10 kDa) were recognized in the serum obtained from the ducklings infected with S. Enteritidis, S. Typhimurium, S. Virchow, S. Shubra, S. Haifa and S. Eingedi after 24 h of infection. After 48 h, the 1-7 kDa HSP became more evident and indicated their de novo generation.

  5. Heat Shock Protein-27 Delays Acute Rejection After Cardiac Transplantation: An Experimental Model

    OpenAIRE

    2014-01-01

    Background Rejection is the major obstacle to survival after cardiac transplantation. We investigated whether overexpression of heat shock protein (Hsp)-27 in mouse hearts protects against acute rejection and the mechanisms of such protection. Methods Hearts from B10.A mice overexpressing human Hsp-27 (Hsp-27tg), or Hsp-27–negative hearts from littermate controls (LCs) were transplanted into allogeneic C57BL/6 mice. The immune response to B10.A hearts was investigated using quantitative polym...

  6. Mathematical Modeling of the Heat-Shock Response in HeLa Cells

    Science.gov (United States)

    2015-07-01

    Rakesh1 1Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research...NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) U.S. Army Medical Research and Materiel Command,DoD Biotechnology High...shock response have already been used as components of larger mathematical models for predicting inflammation in heat stroke (33) and optimizing cancer

  7. Involvement of heat shock proteins on Mn-induced toxicity in Caenorhabditis elegans.

    Science.gov (United States)

    Avila, Daiana Silva; Benedetto, Alexandre; Au, Catherine; Bornhorst, Julia; Aschner, Michael

    2016-11-02

    All living cells display a rapid molecular response to adverse environmental conditions, and the heat shock protein family reflects one such example. Hence, failing to activate heat shock proteins can impair the cellular response. In the present study, we evaluated whether the loss of different isoforms of heat shock protein (hsp) genes in Caenorhabditis elegans would affect their vulnerability to Manganese (Mn) toxicity. We exposed wild type and selected hsp mutant worms to Mn (30 min) and next evaluated further the most susceptible strains. We analyzed survival, protein carbonylation (as a marker of oxidative stress) and Parkinson's disease related gene expression immediately after Mn exposure. Lastly, we observed dopaminergic neurons in wild type worms and in hsp-70 mutants following Mn treatment. Analysis of the data was performed by one-way or two way ANOVA, depending on the case, followed by post-hoc Bonferroni test if the overall p value was less than 0.05. We verified that the loss of hsp-70, hsp-3 and chn-1 increased the vulnerability to Mn, as exposed mutant worms showed lower survival rate and increased protein oxidation. The importance of hsp-70 against Mn toxicity was then corroborated in dopaminergic neurons, where Mn neurotoxicity was aggravated. The lack of hsp-70 also blocked the transcriptional upregulation of pink1, a gene that has been linked to Parkinson's disease. Taken together, our data suggest that Mn exposure modulates heat shock protein expression, particularly HSP-70, in C. elegans. Furthermore, loss of hsp-70 increases protein oxidation and dopaminergic neuronal degeneration following manganese exposure, which is associated with the inhibition of pink1 increased expression, thus potentially exacerbating the vulnerability to this metal.

  8. Flat Plate and Turbine Vane Cascade Heat Transfer Investigation Using a Shock Tube.

    Science.gov (United States)

    1985-12-01

    piece of -. work would not have been possible without the superior and talented AFIT Shop personnel lead by Mr. Carl Shortt. I would also like to...tube. Curves were presented showing the time required to reach steady state for a given flow condition and model size. Davies and Berstein (1969...inverse of Davies’ and Bersteins ’ I alpha as the transition requirement. Dunn and Stoddard (1977) .. * .conducted heat transfer experiments in a shock

  9. Interplay between RNA interference and heat shock response systems in Drosophila melanogaster

    OpenAIRE

    2016-01-01

    The genome expression pattern is strongly modified during the heat shock response (HSR) to form an adaptive state. This may be partly achieved by modulating microRNA levels that control the expression of a great number of genes that are embedded within the gene circuitry. Here, we investigated the cross-talk between two highly conserved and universal house-keeping systems, the HSR and microRNA machinery, in Drosophila melanogaster. We demonstrated that pronounced interstrain differences in th...

  10. Discovery of Benzisoxazoles as Potent Inhibitors of Chaperone Heat Shock Protein 90

    Energy Technology Data Exchange (ETDEWEB)

    Gopalsamy, Ariamala; Shi, Mengxiao; Golas, Jennifer; Vogan, Erik; Jacob, Jaison; Johnson, Mark; Lee, Frederick; Nilakantan, Ramaswamy; Petersen, Roseann; Svenson, Kristin; Chopra, Rajiv; Tam, May S.; Wen, Yingxia; Ellingboe, John; Arndt, Kim; Boschelli, Frank (Wyeth)

    2008-08-11

    Heat shock protein 90 (Hsp90) is a molecular chaperone that is responsible for activating many signaling proteins and is a promising target in tumor biology. We have identified small-molecule benzisoxazole derivatives as Hsp90 inhibitors. Crystallographic studies show that these compounds bind in the ATP binding pocket interacting with the Asp93. Structure based optimization led to the identification of potent analogues, such as 13, with good biochemical profiles.

  11. Structure and function of small heat shock/alpha-crystallin proteins: established concepts and emerging ideas.

    Science.gov (United States)

    MacRae, T H

    2000-06-01

    Small heat shock/alpha-crystallin proteins are defined by conserved sequence of approximately 90 amino acid residues, termed the alpha-crystallin domain, which is bounded by variable amino- and carboxy-terminal extensions. These proteins form oligomers, most of uncertain quaternary structure, and oligomerization is prerequisite to their function as molecular chaperones. Sequence modelling and physical analyses show that the secondary structure of small heat shock/alpha-crystallin proteins is predominately beta-pleated sheet. Crystallography, site-directed spin-labelling and yeast two-hybrid selection demonstrate regions of secondary structure within the alpha-crystallin domain that interact during oligomer assembly, a process also dependent on the amino terminus. Oligomers are dynamic, exhibiting subunit exchange and organizational plasticity, perhaps leading to functional diversity. Exposure of hydrophobic residues by structural modification facilitates chaperoning where denaturing proteins in the molten globule state associate with oligomers. The flexible carboxy-terminal extension contributes to chaperone activity by enhancing the solubility of small heat shock/alpha-crystallin proteins. Site-directed mutagenesis has yielded proteins where the effect of the change on structure and function depends upon the residue modified, the organism under study and the analytical techniques used. Most revealing, substitution of a conserved arginine residue within the alpha-crystallin domain has a major impact on quaternary structure and chaperone action probably through realignment of beta-sheets. These mutations are linked to inherited diseases. Oligomer size is regulated by a stress-responsive cascade including MAPKAP kinase 2/3 and p38. Phosphorylation of small heat shock/alpha-crystallin proteins has important consequences within stressed cells, especially for microfilaments.

  12. Seasonal effects of heat shock on bacterial populations, including artificial Vibrio parahaemolyticus exposure, in the Pacific oyster, Crassostrea gigas.

    Science.gov (United States)

    Aagesen, Alisha M; Häse, Claudia C

    2014-04-01

    During the warmer summer months, oysters are conditioned to spawn, resulting in massive physiological efforts for gamete production. Moreover, the higher temperatures during the summer typically result in increased bacteria populations in oysters. We hypothesized that these animals are under multiple stresses that lead to possible immune system impairments during the summer months that can possibly lead to death. Here we show that in the summer and the fall animals exposed to a short heat stress respond similarly, resulting in a general trend of more bacteria being found in heat shocked animals than their non-heat shocked counterparts. We also show that naturally occurring bacterial populations are effected by a heat shock. In addition, oysters artificially contaminated with Vibrio parahaemolyticus were also affected by a heat shock. Heat shocked animals contained higher concentrations of V. parahaemolyticus in their tissues and hemolymph than control animals and this was consistent for animals examined during summer and fall. Finally, oyster hemocyte interactions with V. parahaemolyticus differed based on the time of the year. Overall, these findings demonstrate that seasonal changes and/or a short heat shock is sufficient to impact bacterial retention, particularly V. parahaemolyticus, in oysters and this line of research might lead to important considerations for animal harvesting procedures.

  13. Cytoprotective effects of cerium and selenium nanoparticles on heat-shocked human dermal fibroblasts: an in vitro evaluation

    Directory of Open Access Journals (Sweden)

    Yuan B

    2016-04-01

    Full Text Available Bo Yuan, Thomas J Webster, Amit K Roy Chemical Engineering Department, College of Engineering, Northeastern University, Boston, MA, USA Abstract: It is a widely accepted fact that environmental factors affect cells by modulating the components of subcellular compartments and altering metabolic enzymes. Factors (such as oxidative stress and heat-shock-induced proteins and heat shock factors, which upregulate stress-response related genes to protect affected cells are commonly altered during changes in environmental conditions. Studies by our group and others have shown that nanoparticles (NPs are able to efficiently attenuate oxidative stress by penetrating into specific tissues or organs. Such findings warrant further investigation on the effects of NPs on heat-shock-induced stress, specifically in cells in the presence or absence (pretreated of NPs. Here, we examined the cytoprotective effects of two different NPs (cerium and selenium on heat-induced cell death for a model cell using dermal fibroblasts. We report for the first time that both ceria and selenium NPs (at 500 µg/mL possess stress-relieving behavior on fibroblasts undergoing heat shock. Such results indicate the need to further develop these NPs as a novel treatment for heat shock. Keywords: ceria, heat shock, nanotechnology, cell death, nanomedicine, protective

  14. Elevation of heat shock gene expression from static magnetic field exposure in vitro.

    Science.gov (United States)

    Laramee, Craig B; Frisch, Paul; McLeod, Kenneth; Li, Gloria C

    2014-09-01

    Previously, we found that extremely low frequency (ELF) electric fields were able to elicit an approximate 3.5-fold increase in heat shock gene expression, a response which may have applicability to cancer therapy. Based on recent studies demonstrating the ability of magnetic fields to influence gene expression, we hypothesized that low level static magnetic fields may be able to affect heat shock gene expression while avoiding some of the clinical difficulties that arise with electric fields. Transfected rat primary cells in monolayer were exposed to magnetic fields of 1 to 440 mT for 16, 24, or 48 h starting at 24 and 48 h post transfection. Heat shock protein (HSP70) expression, as indicated by a promoter linked luciferase reporter, was followed for up to 96 h and showed a dependence on flux density, exposure duration, and start time post transfection. A nonlinear response was observed for increasing flux density with a maximum of a 3.5-fold increase in expression for 48 h of exposure starting 48 h after transfection. These results demonstrate an enhancement of gene expression similar in magnitude to that observed with external electric field exposure, while eliminating many of the clinical complications.

  15. Unrestrained AMPylation targets cytosolic chaperones and activates the heat shock response

    Science.gov (United States)

    Truttmann, Matthias C.; Zheng, Xu; Hanke, Leo; Damon, Jadyn R.; Grootveld, Monique; Krakowiak, Joanna; Pincus, David; Ploegh, Hidde L.

    2017-01-01

    Protein AMPylation is a conserved posttranslational modification with emerging roles in endoplasmic reticulum homeostasis. However, the range of substrates and cell biological consequences of AMPylation remain poorly defined. We expressed human and Caenorhabditis elegans AMPylation enzymes—huntingtin yeast-interacting protein E (HYPE) and filamentation-induced by cyclic AMP (FIC)-1, respectively—in Saccharomyces cerevisiae, a eukaryote that lacks endogenous protein AMPylation. Expression of HYPE and FIC-1 in yeast induced a strong cytoplasmic Hsf1-mediated heat shock response, accompanied by attenuation of protein translation, massive protein aggregation, growth arrest, and lethality. Overexpression of Ssa2, a cytosolic heat shock protein (Hsp)70, was sufficient to partially rescue growth. In human cell lines, overexpression of active HYPE similarly induced protein aggregation and the HSF1-dependent heat shock response. Excessive AMPylation also abolished HSP70-dependent influenza virus replication. Our findings suggest a mode of Hsp70 inactivation by AMPylation and point toward a role for protein AMPylation in the regulation of cellular protein homeostasis beyond the endoplasmic reticulum. PMID:28031489

  16. Heat Shock Protein A2 (HSPA2): Regulatory Roles in Germ Cell Development and Sperm Function.

    Science.gov (United States)

    Nixon, Brett; Bromfield, Elizabeth G; Cui, Jinwei; De Iuliis, Geoffry N

    2017-01-01

    Among the numerous families of heat shock protein (HSP) that have been implicated in the regulation of reproductive system development and function, those belonging to the 70 kDa HSP family have emerged as being indispensable for male fertility. In particular, the testis-enriched heat shock 70 kDa protein 2 (HSPA2) has been shown to be critical for the progression of germ cell differentiation during spermatogenesis in the mouse model. Beyond this developmentally important window, mounting evidence has also implicated HSPA2 in the functional transformation of the human sperm cell during their ascent of the female reproductive tract. Specifically, HSPA2 appears to coordinate the remodelling of specialised sperm domains overlying the anterior region of the sperm head compatible with their principle role in oocyte recognition. The fact that levels of the HSPA2 protein in mature spermatozoa tightly correlate with the efficacy of oocyte binding highlight its utility as a powerful prognostic biomarker of male fertility. In this chapter, we consider the unique structural and biochemical characteristics of HSPA2 that enable this heat shock protein to fulfil its prominent roles in orchestrating the morphological differentiation of male germ cells during spermatogenesis as well as their functional transformation during post-testicular sperm maturation.

  17. Impact of Exercise and Metabolic Disorders on Heat Shock Proteins and Vascular Inflammation

    Directory of Open Access Journals (Sweden)

    Earl G. Noble

    2012-01-01

    Full Text Available Heat shock proteins (Hsp play critical roles in the body’s self-defense under a variety of stresses, including heat shock, oxidative stress, radiation, and wounds, through the regulation of folding and functions of relevant cellular proteins. Exercise increases the levels of Hsp through elevated temperature, hormones, calcium fluxes, reactive oxygen species (ROS, or mechanical deformation of tissues. Isotonic contractions and endurance- type activities tend to increase Hsp60 and Hsp70. Eccentric muscle contractions lead to phosphorylation and translocation of Hsp25/27. Exercise-induced transient increases of Hsp inhibit the generation of inflammatory mediators and vascular inflammation. Metabolic disorders (hyperglycemia and dyslipidemia are associated with type 1 diabetes (an autoimmune disease, type 2 diabetes (the common type of diabetes usually associated with obesity, and atherosclerotic cardiovascular disease. Metabolic disorders activate HSF/Hsp pathway, which was associated with oxidative stress, increased generation of inflammatory mediators, vascular inflammation, and cell injury. Knock down of heat shock factor-1 (HSF1 reduced the activation of key inflammatory mediators in vascular cells. Accumulating lines of evidence suggest that the activation of HSF/Hsp induced by exercise or metabolic disorders may play a dual role in inflammation. The benefits of exercise on inflammation and metabolism depend on the type, intensity, and duration of physical activity.

  18. Effect of heat shock on poly(ADP-ribose) synthetase and DNA repair in Drosophila cells

    Energy Technology Data Exchange (ETDEWEB)

    Nolan, N.L.; Kidwell, W.R.

    1982-04-01

    Poly(ADP-ribose) synthetase, a chromatin-bound enzyme which attaches polyanionic chains of ADP-ribose to nuclear proteins, was found to be temperature sensitive in intact Drosophila melanogaster cells. The synthetase was completely inactivated by heat-shocking the cells at 37/sup 0/C for 5 min, a condition which had no appreciable effect on the subsequent growth of Drosophila cells at their physiological temperature. The heat-shock effect on synthetase was reversible; enzyme activity began to reappear about 2 hr post heat shock. During the 2-hr interval when poly(ADP-ribose) synthetase was absent, the cells were competent in repair of ..gamma..-ray-induced DNA strand breaks as shown by DNA sedimentation studies on alkaline sucrose gradients. It is thus concluded that poly(ADP-ribose) synthesis is unnecessary for repair of DNA strand breaks introduced by irradiation. The same conclusion was reached from the fact that two inhibitors of poly(ADP-ribose) synthetase 3-aminobenzamide and 5-methylnicotinamide, failed to block repair of ..gamma..-ray-induced DNA chain breaks even though both inhibitors reduced the amount of poly(ADP-ribose) synthesized in cells by 50-75%. Although it was found that the repair of DNA strand breaks is independent of poly(ADP-ribose) synthesis, irradiation does activate the synthetase in control cells, as shown by radioimmunoassay of poly(ADP-ribose) levels.

  19. Seed germination of montane forest species in response to ash, smoke and heat shock in Mexico

    Science.gov (United States)

    Zuloaga-Aguilar, Susana; Briones, Oscar; Orozco-Segovia, Alma

    2011-05-01

    In many fire-prone ecosystems, seed germination is triggered by heat shock, smoke, ash and charred wood. However, few studies concerning the effect of these fire products on the germination of tropical and subtropical species exist. We assessed the effect of fire products and their interactions on seed germination in 12 species that frequently grow in burned areas of pine-oak and mixed forest in a mountainous subtropical area. Each species was exposed to a predetermined treatment of heat shock, which was optimised in accordance with a previous study. For smoke treatments, seeds were immersed in smoke water, whereas for ash treatments, 1.5 g of ash was added to the incubation medium. Germination increased in 92% of the species in response to the products of fire. Both the smoke water and the ash treatments promoted germination in four species that had permeable seed covers and physiological dormancy. Six species with physical dormancy required both heat shock and smoke water or ash to break dormancy. Our results indicate that seed germination response to fire products depends on the species and/or dormancy type. The germination response to the fire products varied between species; therefore, fire products may influence the species composition in post-fire regeneration.

  20. Module-based analysis of robustness tradeoffs in the heat shock response system.

    Directory of Open Access Journals (Sweden)

    Hiroyuki Kurata

    2006-07-01

    Full Text Available Biological systems have evolved complex regulatory mechanisms, even in situations where much simpler designs seem to be sufficient for generating nominal functionality. Using module-based analysis coupled with rigorous mathematical comparisons, we propose that in analogy to control engineering architectures, the complexity of cellular systems and the presence of hierarchical modular structures can be attributed to the necessity of achieving robustness. We employ the Escherichia coli heat shock response system, a strongly conserved cellular mechanism, as an example to explore the design principles of such modular architectures. In the heat shock response system, the sigma-factor sigma32 is a central regulator that integrates multiple feedforward and feedback modules. Each of these modules provides a different type of robustness with its inherent tradeoffs in terms of transient response and efficiency. We demonstrate how the overall architecture of the system balances such tradeoffs. An extensive mathematical exploration nevertheless points to the existence of an array of alternative strategies for the existing heat shock response that could exhibit similar behavior. We therefore deduce that the evolutionary constraints facing the system might have steered its architecture toward one of many robustly functional solutions.

  1. Shock-tube studies of radiative base heating of Jovian probe

    Science.gov (United States)

    Shirai, H.; Park, C.

    1980-01-01

    A 6.4-cm-diameter scale model of the Jovian entry vehicle is tested in an electric-arc-driven shock tube and a 5-cm-diameter sphere model is tested in a combustion-driven shock tube and in an electric-arc-driven shock tunnel. The radiative heat-transfer rate and pressure on the front and the base regions are measured in the absence of ablation with sensors imbedded in the models in a stream consisting of 10% hydrogen in a bath of either neon or argon. The measured radiative heat-transfer rates and pressures range to about 22 kW/sq cm and 12 atm, respectively, at the front stagnation point. The ratio of the radiative heat-transfer rate at the base stagnation point to that at the front stagnation point is found to be about 1/4 for the sphere at Mach 1.8, about 1/30 for the sphere at Mach 4.8, and about 1/6 for the scale model at Mach 1.7. The present experimental results agree well with the theoretical predictions of Park, thus indicating that Park's theory is valid.

  2. Relationship between heat shock protein 70 expression and life span in Daphnia.

    Science.gov (United States)

    Schumpert, Charles; Handy, Indhira; Dudycha, Jeffry L; Patel, Rekha C

    2014-07-01

    The longevity of an organism is directly related to its ability to effectively cope with cellular stress. Heat shock response (HSR) protects the cells against accumulation of damaged proteins after exposure to elevated temperatures and also in aging cells. To understand the role of Hsp70 in regulating life span of Daphnia, we examined the expression of Hsp70 in two ecotypes that exhibit strikingly different life spans. Daphnia pulicaria, the long lived ecotype, showed a robust Hsp70 induction as compared to the shorter lived Daphnia pulex. Interestingly, the short-lived D. pulex isolates showed no induction of Hsp70 at the mid point in their life span. In contrast to this, the long-lived D. pulicaria continued to induce Hsp70 expression at an equivalent age. We further show that the Hsp70 expression was induced at transcriptional level in response to heat shock. The transcription factor responsible for Hsp70 induction, heat shock factor-1 (HSF-1), although present in aged organisms did not exhibit DNA-binding capability. Thus, the decline of Hsp70 induction in old organisms could be attributed to a decline in HSF-1's DNA-binding activity. These results for the first time, present a molecular analysis of the relationship between HSR and life span in Daphnia. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  3. Growth enhancement effects of radish sprouts: atmospheric pressure plasma irradiation vs. heat shock

    Science.gov (United States)

    Sarinont, T.; Amano, T.; Kitazaki, S.; Koga, K.; Uchida, G.; Shiratani, M.; Hayashi, N.

    2014-06-01

    We compare growth enhancement effects due to atmospheric air dielectric barrier discharge plasma irradiation and heat shock to seeds of radish sprouts (Raphanus sativus L.). Interactions between radicals and seeds in a short duration of 3 min. lead to the growth enhancement of radish sprouts in a long term of 7 days and the maximum average length is 3.7 times as long as that of control. The growth enhancement effects become gradually weak with time, and hence the ratio of the average length for plasma irradiation to that for control decreases from 3.7 for the first day to 1.3 for 7 day. The average length for heat shock of 60°C for 10 min. and 100°C for 3 min. is longer than that for control, and the maximum average length is 1.3 times as long as that of control. Heat shock has little contribution to the growth enhancement due to plasma irradiation, because the maximum temperature due to plasma irradiation is less than 60°C.

  4. Early and Late Heat Shock Proteins in Wheats and Other Cereal Species 1

    Science.gov (United States)

    Necchi, Ada; Pogna, Norberto E.; Mapelli, Sergio

    1987-01-01

    Coleoptiles and roots of 3-day-old seedlings from five cereal species (Triticum aestivum L., T. durum Desf., Hordeum vulgare L., Secale cereale L., and Triticale) respond to heat shock at 40°C by synthesizing a new set of 13 strong bands (as revealed by one-dimensional sodium dodecyl sulfate gel electrophoresis) as well as some 20°C proteins. Heat shock proteins (HSPs) belong to three different size groups: high molecular mass HSPs in the 103 to 70 kilodalton range, intermediate molecular mass HSPs in the 62 to 32 kilodalton range, and low molecular mass HSPs about 17 to 16 kilodalton in size. At the beginning of the heat shock coleoptiles show a reduced ability to synthesize intermediate molecular mass HSPs but after 4 hours at 40°C they exhibit fully developed HSP patterns identical to that found in roots. Synthesis of early HSPs declines after 7 hours of treatment followed by the appearance of a new set of 12 protein bands (late HSPs) in the ranges 99 to 83, 69 to 35, and 15 to 14 kilodaltons. After 12 hours at 40°C, three other late HSPs of 89, 45, and 38 kilodalton are induced. The induction of late HSPs after 7 hours at 40°C appears to be associated with an enhancement of radioactive methionine incorporation into proteins. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 PMID:16665614

  5. Biological stress responses to radio frequency electromagnetic radiation: are mobile phones really so (heat) shocking?

    Science.gov (United States)

    Cotgreave, Ian A

    2005-03-01

    Cells phenotypically adapt to alterations in their intra- and extracellular environment via organised alterations to gene and protein expression. Many chemical and physical stimuli are known to drive such responses, including the induction of oxidative stress and heat shock. Increasing use of mobile telephones in our society, has brought focus on the potential for radio frequency (microwave) electromagnetic radiation to elicit biological stress responses, in association with potentially detrimental effects of this to human health. Here we review evidence suggesting altered gene and protein expression in response to such emissions, with particular focus on heat shock proteins. Non-thermal induction of heat shock proteins has been claimed by a number of investigations in in vitro cellular systems, and appears pleiotropic for many other regulatory events. However, many of these studies are flawed by inconsistencies in exposure models, cell types used and the independent reproducibility of the findings. Further, the paucity of evidence from in vivo experimentation is largely contradictory. Therefore, the validity of these effects in human health risk assessment remain unsubstantiated. Where possible, suggestions for further experimental clarification have been provided.

  6. Heat Shock Proteins: Intestinal Gatekeepers that Are Influenced by Dietary Components and the Gut Microbiota

    Directory of Open Access Journals (Sweden)

    Haoyu Liu

    2014-02-01

    Full Text Available Trillions of microorganisms that inhabit the intestinal tract form a diverse and intricate ecosystem with a deeply embedded symbiotic relationship with their hosts. As more detailed information on gut microbiota complexity and functional diversity accumulates, we are learning more about how diet-microbiota interactions can influence the immune system within and outside the gut and host health in general. Heat shock proteins are a set of highly conserved proteins that are present in all types of cells, from microbes to mammals. These proteins carry out crucial intracellular housekeeping functions and unexpected extracellular immuno-regulatory features in order to maintain the mucosal barrier integrity and gut homeostasis. It is becoming evident that the enteric microbiota is one of the major determinants of heat shock protein production in intestinal epithelial cells. This review will focus on the interactions between diet, gut microbiota and their role for regulating heat shock protein production and, furthermore, how these interactions influence the immune system and the integrity of the mucosal barrier.

  7. Dendritic-tumor fusion cells derived heat shock protein70-peptide complex has enhanced immunogenicity.

    Science.gov (United States)

    Zhang, Yunfei; Zhang, Yong; Chen, Jun; Liu, Yunyan; Luo, Wen

    2015-01-01

    Tumor-derived heat shock protein70-peptide complexes (HSP70.PC-Tu) have shown great promise in tumor immunotherapy due to numerous advantages. However, large-scale phase III clinical trials showed that the limited immunogenicity remained to be enhanced. In previous research, we demonstrated that heat shock protein 70-peptide complexes (HSP70.PC-Fc) derived from dendritic cell (DC)-tumor fusions exhibit enhanced immunogenicity compared with HSP70.PCs from tumor cells. However, the DCs used in our previous research were obtained from healthy donors and not from the patient population. In order to promote the clinical application of these complexes, HSP70.PC-Fc was prepared from patient-derived DC fused directly with patient-derived tumor cells in the current study. Our results showed that compared with HSP70.PC-Tu, HSP70.PC-Fc elicited much more powerful immune responses against the tumor from which the HSP70 was derived, including enhanced T cell activation, and CTL responses that were shown to be antigen specific and HLA restricted. Our results further indicated that the enhanced immunogenicity is related to the activation of CD4+ T cells and increased association with other heat shock proteins, such as HSP90. Therefore, the current study confirms the enhanced immunogenicity of HSP70.PC derived from DC-tumor fusions and may provide direct evidence promoting their future clinical use.

  8. Neurotoxicity induced by arsenic in Gallus Gallus: Regulation of oxidative stress and heat shock protein response.

    Science.gov (United States)

    Zhao, Panpan; Guo, Ying; Zhang, Wen; Chai, Hongliang; Xing, Houjuan; Xing, Mingwei

    2017-01-01

    Arsenic, a naturally occurring heavy metal pollutant, is one of the functioning risk factors for neurological toxicity in humans. However, little is known about the effects of arsenic on the nervous system of Gallus Gallus. To investigate whether arsenic induce neurotoxicity and influence the oxidative stress and heat shock proteins (Hsps) response in chickens, seventy-two 1-day-old male Hy-line chickens were treated with different doses of arsenic trioxide (As2O3). The histological changes, antioxidant enzyme activity, and the expressions of Hsps were detected. Results showed slightly histology changes were obvious in the brain tissues exposure to arsenic. The activities of Glutathione peroxidase (GSH-Px) and catalase (CAT) were decreased compared to the control, whereas the malondialdehyde (MDA) content was increased gradually along with increase in diet-arsenic. The mRNA levels of Hsps and protein expressions of Hsp60 and Hsp70 were up-regulated. These results suggested that sub-chronic exposure to arsenic induced neurotoxicity in chickens. Arsenic exposure disturbed the balance of oxidants and antioxidants. Increased heat shock response tried to protect chicken brain tissues from tissues damage caused by oxidative stress. The mechanisms of neurotoxicity induced by arsenic include oxidative stress and heat shock protein response in chicken brain tissues.

  9. Transcriptional Activation of a Constitutive Heterochromatic Domain of the Human Genome in Response to Heat ShockD⃞

    Science.gov (United States)

    Rizzi, Nicoletta; Denegri, Marco; Chiodi, Ilaria; Corioni, Margherita; Valgardsdottir, Rut; Cobianchi, Fabio; Riva, Silvano; Biamonti, Giuseppe

    2004-01-01

    Heat shock triggers the assembly of nuclear stress bodies that contain heat shock factor 1 and a subset of RNA processing factors. These structures are formed on the pericentromeric heterochromatic regions of specific human chromosomes, among which chromosome 9. In this article we show that these heterochromatic domains are characterized by an epigenetic status typical of euchromatic regions. Similarly to transcriptionally competent portions of the genome, stress bodies are, in fact, enriched in acetylated histone H4. Acetylation peaks at 6 h of recovery from heat shock. Moreover, heterochromatin markers, such as HP1 and histone H3 methylated on lysine 9, are excluded from these nuclear districts. In addition, heat shock triggers the transient accumulation of RNA molecules, heterogeneous in size, containing the subclass of satellite III sequences found in the pericentromeric heterochromatin of chromosome 9. This is the first report of a transcriptional activation of a constitutive heterochromatic portion of the genome in response to stress stimuli. PMID:14617804

  10. Assessment of heat shock protein 70 induction by heat in alfalfa varieties and constitutive overexpression in transgenic plants.

    Directory of Open Access Journals (Sweden)

    Nicoletta Ferradini

    Full Text Available Heat shock proteins (HSPs are molecular chaperones involved in many cellular functions. It has been shown that mammalian cytosolic HSP70 binds antigenic peptides mediating the activation of the immune system, and that it plays a determining role in tumour immunogenicity. This suggests that HSP70 may be used for the production of conjugated vaccines. Human and plant HSPs share high sequence similarity and some important biological functions in vitro. In addition, plant HSPs have no endotoxic side effects. Extraction of HSP70 from plants for use as vaccine adjuvant requires enhancing its concentration in plant tissues. In this work, we explored the possibility to produce HSP70 in both transgenic and non-transgenic plants, using alfalfa as a model species. First, a transcriptional analysis of a constitutive and an inducible HSP70 genes was conducted in Arabidopsis thaliana. Then the coding sequence of the inducible form was cloned and introduced into alfalfa by Agrobacterium-mediated transformation, and the accumulation of the protein in leaf tissue of transgenic plants was demonstrated. We also tested diverse alfalfa varieties for heat-inducible expression of endogenous HSP70, revealing variety-specific responses to heat shock.

  11. Propagation of a cylindrical shock wave in a rotating dusty gas with heat conduction and radiation heat flux

    Science.gov (United States)

    Vishwakarma, J. P.; Nath, G.

    2010-04-01

    A self-similar solution for the propagation of a cylindrical shock wave in a dusty gas with heat conduction and radiation heat flux, which is rotating about the axis of symmetry, is investigated. The shock is assumed to be driven out by a piston (an inner expanding surface) and the dusty gas is assumed to be a mixture of non-ideal gas and small solid particles. The density of the ambient medium is assumed to be constant. The heat conduction is expressed in terms of Fourier's law and radiation is considered to be of diffusion type for an optically thick grey gas model. The thermal conductivity K and the absorption coefficient αR are assumed to vary with temperature and density. Similarity solutions are obtained, and the effects of variation of the parameter of non-idealness of the gas in the mixture, the mass concentration of solid particles and the ratio of density of solid particles to the initial density of the gas are investigated.

  12. Stomatal movement in response to long distance- communicated signals initiated by heat shock in partial roots of Commelina communis L.

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The systematic or long-distance signal transmission plays crucial roles in animal lives. Compared with animals, however, much less is known about the roles of long-distance signal communication in plant lives. Using the model plant Commelina communis L., we have probed the root to shoot communication mediated by heat-shock signals. The results showed that a heat shock of 5 min at 40℃ in partial roots, i.e. half or even 1/4 root system, could lead to a significant decrease in stomatal conductance. The regulation capability depends on both heat shock temperature and the amount of root system, i.e. with higher temperature and more roots stressed, the leaf conductance would decrease more significantly. Interestingly, the stomatal regulation by heat shock signal is in a manner of oscillation: when stomata conductance decreased to the lowest level within about 30 min, it would increase rapidly and sometimes even exceed the initial level, and after several cycles the stomata conductance would be finally stabilized at a lower level. Feeding xylem sap collected from heat-shocked plants could lead to a decrease in stomata conductance, suggesting that the heat shock-initiated signal is basically a positive signal. Further studies showed that heat shock was not able to affect ABA content in xylem sap, and also, not able to lead to a decrease in leaf water status, which suggested that the stomatal regulation was neither mediated by ABA nor by a hydraulic signal. Heat shock could lead to an increase in xylem sap H2O2 content, and moreover, the removal of H2O2 by catalase could partially recover the stomatal inhibition by xylem sap collected from heat-shocked plants, suggesting that H2O2 might be able to act as one of the root signals to control the stomatal movement. Due to the fact that heat-shock and drought are usually two concomitant stresses, the stomatal regulation by heat-shock signal should be of significance for plant response to stresses. The observation for the

  13. Small heat shock protein Hsp27 protects myosin S1 from heat-induced aggregation, but not from thermal denaturation and ATPase inactivation.

    Science.gov (United States)

    Markov, Denis I; Pivovarova, Anastasia V; Chernik, Ivan S; Gusev, Nikolai B; Levitsky, Dmitrii I

    2008-04-30

    We applied different methods, such as turbidity measurements, dynamic light scattering, differential scanning calorimetry and co-sedimentation assay, to analyze the interaction of small heat shock protein Hsp27 with isolated myosin head (myosin subfragment 1, S1) under heat-stress conditions. Upon heating at 43 degrees C, Hsp27 effectively suppresses S1 aggregation, and this effect is enhanced by mutations mimicking Hsp27 phosphorylation. However, Hsp27 was unable to prevent thermal unfolding of myosin heads and to maintain their ATPase activity under heat-shock conditions.

  14. Effect of patchouli alcohol on the regulation of heat shock-induced oxidative stress in IEC-6 cells.

    Science.gov (United States)

    Liu, Xiaoxi; Jiang, Linshu; Liu, Fenghua; Chen, Yuping; Xu, Lei; Li, Deyin; Ma, Yunfei; Li, Huanrong; Xu, Jianqin

    2016-08-01

    Purpose Patchouli alcohol (PA) is used to treat gastrointestinal dysfunction. The purpose of this study was to ascertain the function of PA in the regulated process of oxidative stress in rat intestinal epithelial cells (IEC-6). Materials and methods Oxidative stress was stimulated by exposing IEC-6 cells to heat shock (42 °C for 3 h). IEC-6 cells in treatment groups were pretreated with various concentrations of PA (10, 40, and 80 ng/mL) for 3 h before heat shock. Results Heat shock caused damage to the morphology of IEC-6 cells, and increased reactive oxygen species (ROS) level and malondialdehyde (MDA) content. Moreover, mRNA and protein expression by target genes related to oxidative stress in heat shock were also altered. Specifically, the mRNA expression by HSP70, HSP90, GSH-px, NRF2 nd HO-1were all increased, and Nrf2 and Keap1 protein expression were increased after heat shock. However, pretreatment with PA weakened the level of damage to the cellular morphology, and decreased the MDA content caused by heat shock, indicating PA had cytoprotective activities. Pretreatment with PA at high dose significantly increased generation of intracellular ROS. Compared with the heat shock group alone, PA pretreatment significantly decreased the mRNA expression by HSP70, HSP90, SOD, CAT, GSH-px, KEAP1 and HO-1. Furthermore, the high dose of PA significantly increased Nrf2 protein expression, while both the intermediate and high dose of PA significantly increased HO-1 protein expression. Conclusion Heat-shock-induced oxidative stress in IEC-6 cells, and PA could alleviate the Nrf2-Keap1 cellular oxidative stress responses.

  15. Heat shock protein expression as guidance for the therapeutic window of retinal laser therapy

    Science.gov (United States)

    Wang, Jenny; Huie, Philip; Dalal, Roopa; Lee, Seungjun; Tan, Gavin; Lee, Daeyoung; Lavinksy, Daniel; Palanker, Daniel

    2016-03-01

    Unlike conventional photocoagulation, non-damaging retinal laser therapy (NRT) limits laser-induced heating to stay below the retinal damage threshold and therefore requires careful dosimetry. Without the adverse effects associated with photocoagulation, NRT can be applied to critical areas of the retina and repeatedly to manage chronic disorders. Although the clinical benefits of NRT have been demonstrated, the mechanism of therapeutic effect and width of the therapeutic window below damage threshold are not well understood. Here, we measure activation of heat shock response via laser-induced hyperthermia as one indication of cellular response. A 577 nm laser is used with the Endpoint Management (EpM) user interface, a titration algorithm, to set experimental pulse energies relative to a barely visible titration lesion. Live/dead staining and histology show that the retinal damage threshold in rabbits is at 40% of titration energy on EpM scale. Heat shock protein 70 (HSP70) expression in the retinal pigment epithelium (RPE) was detected by whole-mount immunohistochemistry after different levels of laser treatment. We show HSP70 expression in the RPE beginning at 25% of titration energy indicating that there is a window for NRT between 25% and 40% with activation of the heat shock protein expression in response to hyperthermia. HSP70 expression is also seen at the perimeter of damaging lesions, as expected based on a computational model of laser heating. Expression area for each pulse energy setting varied between laser spots due to pigmentation changes, indicating the relatively narrow window of non-damaging activation and highlighting the importance of proper titration.

  16. Effect of thermal manipulation during embryogenesis on liver heat shock protein expression in chronic heat stressed colored broiler chickens.

    Science.gov (United States)

    Vinoth, A; Thirunalasundari, T; Tharian, Jenny Anne; Shanmugam, M; Rajkumar, U

    2015-10-01

    Thermal manipulation during embryogenesis has been shown to improve thermo tolerance in broilers. Heat shock proteins are a family of proteins produced in response to variety of stress and protect cells from damage. The aim of this study was to evaluate the effect of thermal manipulation (TM) during embryogenesis on HSP gene and protein expression in the embryos and in chronic heat stressed 42nd day old chicks. On 15th day of incubation, fertile eggs from two breeds-Naked neck (NN) and Punjab Broiler-2 (PB-2) were randomly divided in to two groups, namely Control (C) eggs were incubated under standard incubation conditions and Thermal Conditioning (TC) eggs were exposed to higher incubation temperature (40.5°C) for 3h on 15th, 16th and 17th day of incubation. The chicks so obtained from each group were further subdivided and reared from 15th-42nd day as normal (N; 25±1°C, 70% RH) and heat exposed (HE; 35±1°C, 50% RH) resulting in four treatment groups (CN, CHE, TCN and TCHE). Embryos of two groups (C and TC) on 17th day and birds from four treatment groups on 42nd day were sacrificed. Liver was collected for analysis of gene expression by real-time PCR and protein expression by Western blot of Heat Shock Proteins (HSP 90 alpha, HSP 90 beta, HSP 70, HSP 60, HSP 27 and ubiquitin). The plasma collected on 42nd day was analyzed for biochemical parameters. Thermal challenging of embryos of both the breeds caused significant (P≤0.05) increase in all the HSPs gene and protein expression. The TCHE chicks had significantly (P≤0.05) lower HSPs gene and protein expressions and oxidative stress compared to CHE groups in both NN and PB-2. Based on these findings it can be concluded that TM during incubation provides adaptation to broiler chicks during chronic heat stress.

  17. Increased expression of heat shock protein 70 and heat shock factor 1 in chronic dermal ulcer tissues treated with laser-aided therapy

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jian-da; LUO Cheng-qun; XIE Hui-qing; NIE Xin-min; ZHAO Yan-zhong; WANG Shao-hua; XU Yi; Pashupati Babu Pokharel; XU Dan

    2008-01-01

    Background Chronic dermal ulcers are also referred to as refractory ulcers, This study was conducted to elucidate the therapeutic effect of laser on chronic dermal ulcers and the induced expression of heat shock factor 1 (HSF1) and heat shock protein 70 (HSP70) in wound tissues.Methods Sixty patients with 84 chronic dermal ulcers were randomly divided into traditional therapy and laser therapy groups. Laser treatment was performed in addition to traditional therapy in the laser therapy group. The treatment efficacy was evaluated after three weeks. Five tissue sections of healing wounds were randomly collected along with five normal skin sections as controls. HSP70-positive cells from HSP70 immunohistochemical staining were counted and the gray scale of positive cells was measured for statistical analysis. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were performed to determine the mRNA and protein expressions of HSF1 and HSP70.Results The cure rate of the wounds and the total efficacy in the laser therapy group were significantly higher than those in the traditional therapy group (P<0.05, P<0.01, respectively). Immunohistochemical staining revealed that the HSP70-positive cell count was significantly higher in laser therapy group than those in the traditional therapy group and controls (P<0.01), and the gray scale of the cell signal was obviously lower than traditional therapy group and controls (P <0.05). By contrast, the traditional therapy group and the control group were not significantly different. The RNA levels of HSF1 and HSP70 were higher in the laser therapy group by RT-PCR, but very low in normal skin and the traditional therapy group. The analysis on the gray scale of the Western blot bands indicated that the expression of HSF1 and HSP70 in the laser therapy group was significantly higher than in the traditional therapy group and the control group (P <0.01), and the expression in the traditional therapy group was also

  18. Overexpression of Colligin 2 in Glioma Vasculature is Associated with Overexpression of Heat Shock Factor 2.

    Science.gov (United States)

    Mustafa, Dana A M; Sieuwerts, Anieta M; Zheng, Ping Pin; Kros, Johan M

    2010-10-20

    In previous studies we found expression of the protein colligin 2 (heat shock protein 47 (HSP47), SERPINH1) in glioma neovasculature while not in normal brain tissue. Generally, the regulation of heat shock gene expression in eukaryotes is mediated by heat shock factors (HSF). In mammals, three heat shock transcription factors, HSF-1, -2, and -4, have been isolated. Here we investigated the relation between the expression of colligin 2 and these heat shock factors at the mRNA level using real-time reverse transcriptase PCR (qRT-PCR) in different grades of astrocytic tumorigenesis, viz., low-grade glioma and glioblastoma. Endometrium samples, representing physiological angiogenesis, were included as controls. Since colligin 2 is a chaperon for collagens, the gene expression of collagen I (COL1A1) was also investigated. The blood vessel density of the samples was monitored by expression of the endothelial marker CD31 (PECAM1). Because NG2-immunopositive pericytic cells are involved in glioma neovascularization, the expression of NG2 (CSPG4) was also measured.We demonstrate overexpression of HSF2 in both stages of glial tumorigenesis (reaching significance only in low-grade glioma) and also minor elevated levels of HSF1 as compared to normal brain. There were no differences in expression of HSF4 between low-grade glioma and normal brain while HSF4 was downregulated in glioblastoma. In the endometrium samples, none of the HSFs were upregulated. In the low-grade gliomas SERPINH appeared to be slightly overexpressed with a parallel 4-fold upregulation of COL1A1, while in glioblastoma there was over 5-fold overexpression of SERPINH1 and more than 150-fold overexpression of COL1A1. In both the lowgrade gliomas and the glioblastomas overexpression of CSPG4 was found and overexpression of PECAM1 was only found in the latter. Our data suggest that the upregulated expression of colligin 2 in glioma is accompanied by upregulation of COL1A1, CSPG4, HSF2 and to a lesser extent

  19. Experimental Study of Shock-train/Combustion Coupling and Flame Dynamics in a Heated Supersonic Flow

    Science.gov (United States)

    Fotia, Matthew Leonard

    Isolator/combustor interactions are measured in a direct-connect dual-mode ramjet-scramjet experiment. An operating point approach is used to create a mapping of the coupling effects between the isolator geometry, inlet flow conditions and fuel injector behavior. The resulting isolator/injector coupling map provides a description of the response of the isolator to particular injector performance, and the effective blockage it induces on the isolator flow. Existing models and correlations predicting the pressure rise across a pseudo-shock, and its resultant length, were evaluated through comparison with measurements made in a heated-flow isolator duct that is coupled to a hydrogen-air combustor. The observation of a normal-to-oblique shock-train transition mechanism has lead to the development of a revised shock-train operating regime description that takes into account the impact of Mach number and maximum pressure recovery on the shock configurations present in the isolator. The behavior of a ram-scram transition was examined along with pressure measurements and high-speed laser interferometry. The work quantifies the sudden change in the wall static pressure profile and flame position that occurs as the downstream boundary condition abruptly changes when the flow becomes unchoked. Transition was studied in three ways; as a quasi-steady phenomenon, or as caused by rapid variations in either fuel flow-rate or test-section wall temperature. A regime diagram was measured that plots the ram-scram transition boundary. Under certain conditions some periodic low-frequency oscillations of the flame position occur and they are shown to be correlated with oscillations of the upstream pre-combustion pseudo-shock. A self-sustaining shear-layer instability, associated with the flameholding cavity, is identified as the mechanism perpetuating this behavior. The relevant time scales associated with the ram-scram transition and the flame-shock interactions are discussed.

  20. Multilevel comparative analysis of the contributions of genome reduction and heat shock to the Escherichia coli transcriptome

    Directory of Open Access Journals (Sweden)

    Ying Bei-Wen

    2013-01-01

    Full Text Available Abstract Background Both large deletions in genome and heat shock stress would lead to alterations in the gene expression profile; however, whether there is any potential linkage between these disturbances to the transcriptome have not been discovered. Here, the relationship between the genomic and environmental contributions to the transcriptome was analyzed by comparing the transcriptomes of the bacterium Escherichia coli (strain MG1655 and its extensive genomic deletion derivative, MDS42 grown in regular and transient heat shock conditions. Results The transcriptome analysis showed the following: (i there was a reorganization of the transcriptome in accordance with preferred chromosomal periodicity upon genomic or heat shock perturbation; (ii there was a considerable overlap between the perturbed regulatory networks and the categories enriched for differentially expressed genes (DEGs following genome reduction and heat shock; (iii the genes sensitive to genome reduction tended to be located close to genomic scars, and some were also highly responsive to heat shock; and (iv the genomic and environmental contributions to the transcriptome displayed not only a positive correlation but also a negatively compensated relationship (i.e., antagonistic epistasis. Conclusion The contributions of genome reduction and heat shock to the Escherichia coli transcriptome were evaluated at multiple levels. The observations of overlapping perturbed networks, directional similarity in transcriptional changes, positive correlation and epistatic nature linked the two contributions and suggest somehow a crosstalk guiding transcriptional reorganization in response to both genetic and environmental disturbances in bacterium E. coli.

  1. Widespread Inhibition of Posttranscriptional Splicing Shapes the Cellular Transcriptome following Heat Shock

    Directory of Open Access Journals (Sweden)

    Reut Shalgi

    2014-06-01

    Full Text Available During heat shock and other proteotoxic stresses, cells regulate multiple steps in gene expression in order to globally repress protein synthesis and selectively upregulate stress response proteins. Splicing of several mRNAs is known to be inhibited during heat stress, often meditated by SRp38, but the extent and specificity of this effect have remained unclear. Here, we examined splicing regulation genome-wide during heat shock in mouse fibroblasts. We observed widespread retention of introns in transcripts from ∼1,700 genes, which were enriched for tRNA synthetase, nuclear pore, and spliceosome functions. Transcripts with retained introns were largely nuclear and untranslated. However, a group of 580+ genes biased for oxidation reduction and protein folding functions continued to be efficiently spliced. Interestingly, these unaffected transcripts are mostly cotranscriptionally spliced under both normal and stress conditions, whereas splicing-inhibited transcripts are mostly spliced posttranscriptionally. Altogether, our data demonstrate widespread repression of splicing in the mammalian heat stress response, disproportionately affecting posttranscriptionally spliced genes.

  2. Hydrodynamic modelling of accretion impacts in classical T Tauri stars: radiative heating of the pre-shock plasma

    Science.gov (United States)

    Costa, G.; Orlando, S.; Peres, G.; Argiroffi, C.; Bonito, R.

    2017-01-01

    Context. It is generally accepted that, in classical T Tauri stars, the plasma from the circumstellar disc accretes onto the stellar surface with free-fall velocity and the impact generates a shock. The impact region is expected to contribute to emission in different spectral bands; many studies have confirmed that the X-rays arise from the post-shock plasma but, otherwise, there are no studies in the literature investigating the origin of the observed UV emission which is apparently correlated to accretion. Aims: We investigated the effect of radiative heating of the infalling material by the post-shock plasma at the base of the accretion stream, with the aim to identify in which region a significant part of the UV emission originates. Methods: We developed a one-dimensional hydrodynamic model describing the impact of an accretion stream onto the stellar surface; the model takes into account the gravity, the radiative cooling of an optically thin plasma, the thermal conduction, and the heating due to absorption of X-ray radiation. The latter term represents the heating of the infalling plasma due to the absorption of X-rays emitted from the post-shock region. Results: We found that the radiative heating of the pre-shock plasma plays a non-negligible role in the accretion phenomenon. In particular, the dense and cold plasma of the pre-shock accretion column is gradually heated up to a few 105K due to irradiation of X-rays arising from the shocked plasma at the impact region. This heating mechanism does not affect significantly the dynamics of the post-shock plasma. On the other hand, a region of radiatively heated gas (that we consider a precursor) forms in the unshocked accretion column and contributes significantly to UV emission. Our model naturally reproduces the luminosity of UV emission lines correlated to accretion and shows that most of the UV emission originates from the precursor.

  3. Similarity solution for the flow behind a shock wave in a non-ideal gas with heat conduction and radiation heat-flux in magnetogasdynamics

    Science.gov (United States)

    Nath, G.; Vishwakarma, J. P.

    2014-05-01

    The propagation of a spherical (or cylindrical) shock wave in a non-ideal gas with heat conduction and radiation heat-flux, in the presence of a spacially decreasing azimuthal magnetic field, driven out by a moving piston is investigated. The heat conduction is expressed in terms of Fourier's law and the radiation is considered to be of the diffusion type for an optically thick grey gas model. The thermal conductivity K and the absorption coefficient αR are assumed to vary with temperature and density. The gas is assumed to have infinite electrical conductivity and to obey a simplified van der Waals equation of state. The shock wave moves with variable velocity and the total energy of the wave is non-constant. Similarity solutions are obtained for the flow-field behind the shock and the effects of variation of the heat transfer parameters, the parameter of the non-idealness of the gas, both, decreases the compressibility of the gas and hence there is a decrease in the shock strength. Further, it is investigated that with an increase in the parameters of radiative and conductive heat transfer the tendency of formation of maxima in the distributions of heat flux, density and isothermal speed of sound decreases. The pressure and density vanish at the inner surface (piston) and hence a vacuum is form at the center of symmetry. The shock waves in conducting non-ideal gas with conductive and radiative heat fluxes can be important for description of shocks in supernova explosions, in the study of central part of star burst galaxies, nuclear explosion, chemical detonation, rupture of a pressurized vessels, in the analysis of data from exploding wire experiments, and cylindrically symmetric hypersonic flow problems associated with meteors or reentry vehicles, etc. The findings of the present works provided a clear picture of whether and how the non-idealness parameter, conductive and radiative heat transfer parameters and the magnetic field affect the flow behind the shock

  4. Ultrafast Measurement of the Optical Properties of Shocked Nickel and Laser Heated Gold

    Science.gov (United States)

    Funk, David J.; Moore, D. S.; Reho, J. H.; Gahagan, K. T.; McGrane, S. D.; Rabie, R. L.

    2002-07-01

    We have used high-resolution Frequency Domain Interferometry (FDI) to make the first ultrafast measurement of shock-induced changes in the optical properties of thin nickel (approx500 nm) targets. Data taken at several angles of incidence allowed the separation of optical effects from material motion, yielding an effective complex index for the shocked material. In contrast to our previous studies of aluminum, measurements with an 800 nm probe wavelength found a phase shift attributable to optical property changes with the same sign as that due to surface motion, during an 11.5 GPa shock breakout. A similar experiment was attempted with thin gold films (approx180 nm) using Ultrafast Spatial Interferometry (USI). However, since the electron-phonon coupling in gold is extremely weak, a shock is observed as it "forms". Ballistic electrons and electron-electron equilibrium cause fast heating of the electrons in the entire thickness of the thin film, followed by lattice excitation through electron-phonon coupling, eventually leading to melt and frustrated thermal expansion yielding the observed surface motion. We suggest that these experiments offer a new path for observation of phase changes or for temperature measurements, by allowing a determination of the complex index under dynamic loading conditions and comparing the measured values to those obtained under static conditions.

  5. Specific Binding of Tetratricopeptide Repeat Proteins to Heat Shock Protein 70 (Hsp70) and Heat Shock Protein 90 (Hsp90) Is Regulated by Affinity and Phosphorylation.

    Science.gov (United States)

    Assimon, Victoria A; Southworth, Daniel R; Gestwicki, Jason E

    2015-12-01

    Heat shock protein 70 (Hsp70) and heat shock protein 90 (Hsp90) require the help of tetratricopeptide repeat (TPR) domain-containing cochaperones for many of their functions. Each monomer of Hsp70 or Hsp90 can interact with only a single TPR cochaperone at a time, and each member of the TPR cochaperone family brings distinct functions to the complex. Thus, competition for TPR binding sites on Hsp70 and Hsp90 appears to shape chaperone activity. Recent structural and biophysical efforts have improved our understanding of chaperone-TPR contacts, focusing on the C-terminal EEVD motif that is present in both chaperones. To better understand these important protein-protein interactions on a wider scale, we measured the affinity of five TPR cochaperones, CHIP, Hop, DnaJC7, FKBP51, and FKBP52, for the C-termini of four members of the chaperone family, Hsc70, Hsp72, Hsp90α, and Hsp90β, in vitro. These studies identified some surprising selectivity among the chaperone-TPR pairs, including the selective binding of FKBP51/52 to Hsp90α/β. These results also revealed that other TPR cochaperones are only able to weakly discriminate between the chaperones or between their paralogs. We also explored whether mimicking phosphorylation of serine and threonine residues near the EEVD motif might impact affinity and found that pseudophosphorylation had selective effects on binding to CHIP but not other cochaperones. Together, these findings suggest that both intrinsic affinity and post-translational modifications tune the interactions between the Hsp70 and Hsp90 proteins and the TPR cochaperones.

  6. Decrease in penicillin susceptibility due to heat shock protein ClpL in Streptococcus pneumoniae.

    Science.gov (United States)

    Tran, Thao Dang-Hien; Kwon, Hyog-Young; Kim, Eun-Hye; Kim, Ki-Woo; Briles, David E; Pyo, Suhkneung; Rhee, Dong-Kwon

    2011-06-01

    Antibiotic resistance and tolerance are increasing threats to global health as antibiotic-resistant bacteria can cause severe morbidity and mortality and can increase treatment cost 10-fold. Although several genes contributing to antibiotic tolerance among pneumococci have been identified, we report here that ClpL, a major heat shock protein, could modulate cell wall biosynthetic enzymes and lead to decreased penicillin susceptibility. On capsular type 1, 2, and 19 genetic backgrounds, mutants lacking ClpL were more susceptible to penicillin and had thinner cell walls than the parental strains, whereas a ClpL-overexpressing strain showed a higher resistance to penicillin and a thicker cell wall. Although exposure of Streptococcus pneumoniae D39 to penicillin inhibited expression of the major cell wall synthesis gene pbp2x, heat shock induced a ClpL-dependent increase in the mRNA levels and protein synthesized by pbp2x. Inducible ClpL expression correlated with PBP2x expression and penicillin susceptibility. Fractionation and electron micrograph data revealed that ClpL induced by heat shock is localized at the cell wall, and the ΔclpL showed significantly reduced net translocation of PBP2x into the cell wall. Moreover, coimmunoprecipitation with either ClpL or PBP2x antibody followed by reprobing with ClpL or PBP2x antibody showed an interaction between ClpL and PBP2x after heat stress. This interaction was confirmed by His tag pulldown assay with either ClpLHis₆ or PBP2xHis₆. Thus, ClpL stabilized pbp2x expression, interacted with PBP2x, and facilitated translocation of PBP2x, a key protein of cell wall synthesis process, contributing to the decrease of antibiotic susceptibility in S. pneumoniae.

  7. Screening Molecular Chaperones Similar to Small Heat Shock Proteins in Schizosaccharomyces pombe.

    Science.gov (United States)

    Han, Jiyoung; Kim, Kanghwa; Lee, Songmi

    2015-09-01

    To screen molecular chaperones similar to small heat shock proteins (sHsps), but without α-crystalline domain, heat-stable proteins from Schizosaccharomyces pombe were analyzed by 2-dimensional electrophoresis and matrix assisted laser desorption/ionization time-of-flight mass spectrometry. Sixteen proteins were identified, and four recombinant proteins, including cofilin, NTF2, pyridoxin biosynthesis protein (Snz1) and Wos2 that has an α-crystalline domain, were purified. Among these proteins, only Snz1 showed the anti-aggregation activity against thermal denaturation of citrate synthase. However, pre-heating of NTF2 and Wos2 at 70℃ for 30 min, efficiently prevented thermal aggregation of citrate synthase. These results indicate that Snz1 and NTF2 possess molecular chaperone activity similar to sHsps, even though there is no α-crystalline domain in their sequences.

  8. Genome-Wide Analysis and Molecular Characterization of Heat Shock Transcription Factor Family in Glycine max

    Institute of Scientific and Technical Information of China (English)

    Eunsook Chung; Kyoung-Mi Kim; Jai-Heon Lee

    2013-01-01

    Heat shock transcription factors (Hsfs) play an essential role on the increased tolerance against heat stress by regulating the expression of heat-responsive genes.In this study,a genome-wide analysis was performed to identify all of the soybean (Glycine max) GmHsfgenes based on the latest soybean genome sequence.Chromosomal location,protein domain,motif organization,and phylogenetic relationships of 26 non-redundant GmHsf genes were analyzed compared with AtHsfs (Arabidopsis thaliana Hsfs).According to their structural features,the predicted members were divided into the previously defined classes A-C,as described for AtHsfs.Transcript levels and subcellular localization of five GmHsfs responsive to abiotic stresses were analyzed by real-time RT-PCR.These results provide a fundamental clue for understanding the complexity of the soybean GmHsfgene family and cloning the functional genes in future studies.

  9. Laser Heating of Solid Matter by Light-Pressure-Driven Shocks at Ultrarelativistic Intensities

    Energy Technology Data Exchange (ETDEWEB)

    Akli, K.U.; Hansen, S.B.; Kemp, A.J.; Freeman, R.R.; Beg, F.N.; Clark, D.C.; Chen, S.D.; Hey, D.; Hatchett, S.P.; Highbarger, K.; Giraldez, E.; Green, J.S.; Gregori, G.; Lancaster, K.L.; Ma, T.; MacKinnon, A.J.; Norreys, P.; Patel, N.; Pasley, J.; Shearer, C.; Stephens, R.B.; Stoeckl, C.; Storm, M.; Theobald, W.; Van Woerkom, L.D.; Weber, R.; Key, M.H.

    2008-04-29

    The heating of solid targets irradiated by 5 x 10^20 W cm^-2, 0.8 ps, 1.05 um wavelength laser light is studied by x-ray spectroscopy of the K-shell emission from thin layers of Ni, Mo, and V. A surface layer is heated to ~5 keV with an axial temperature gradient of 0.6 um scale length. Images of Ni Ly sub-alpha show the hot region has <25 um diameter. These data are consistent with collisional particle-in-cell simulations using preformed plasma density profiles from hydrodynamic modeling which show that the >100 Gbar light pressure compresses the preformed plasma and dries a shock into the solid, heating a thin layer.

  10. Laser heating of solid matter by light pressure-driven shocks

    Energy Technology Data Exchange (ETDEWEB)

    Akli, K; Hansen, S B; Kemp, A J; Freeman, R R; Beg, F N; Clark, D; Chen, S; Hey, D; Highbarger, K; Giraldez, E; Green, J; Gregori, G; Lancaster, K; Ma, T; MacKinnon, A J; Norreys, P A; Patel, N; Patel, P; Shearer, C; Stephens, R B; Stoeckl, C; Storm, M; Theobald, W; Van Woerkom, L; Weber, R; Key, M H

    2007-05-04

    Heating by irradiation of a solid surface in vacuum with 5 x 10{sup 20} W cm{sup -2}, 0.8 ps, 1.05 {micro}m wavelength laser light is studied by x-ray spectroscopy of the K-shell emission from thin layers of Ni, Mo and V. A surface layer is heated to {approx} 5 keV with an axial temperature gradient of 0.6 {micro}m scale length. Images of Ni Ly{sub {alpha}} show the hot region has a {approx} 25 {micro}m diameter, much smaller than {approx} 70 {micro}m region of K{sub {alpha}} emission. 2D particle-in-cell (PIC) simulations suggest that the surface heating is due to a light pressure driven shock.

  11. Heat Shock Protein Augmentation of Root Hot Water Extract on Adipogenic Differentiation in Murine 3T3-L1 Preadipocytes

    Directory of Open Access Journals (Sweden)

    Wenchie Marie L. Lumbera

    2016-03-01

    Full Text Available There is a high association of heat shock on the alteration of energy and lipid metabolism. The alterations associated with thermal stress are composed of gene expression changes and adaptation through biochemical responses. Previous study showed that Angelica gigas Nakai (AGN root extract promoted adipogenic differentiation in murine 3T3-L1 preadipocytes under the normal temperature condition. However, its effect in heat shocked 3T3-L1 cells has not been established. In this study, we investigated the effect of AGN root hot water extract in the adipogenic differentiation of murine 3T3-L1 preadipocytes following heat shock and its possible mechanism of action. Thermal stress procedure was executed within the same stage of preadipocyte confluence (G0 through incubation at 42°C for one hour and then allowed to recover at normal incubation temperature of 37°C for another hour before AGN treatment for both cell viability assay and Oil Red O. Cell viability assay showed that AGN was able to dose dependently (0 to 400 μg/mL increase cell proliferation under normal incubation temperature and also was able to prevent cytotoxicity due to heat shock accompanied by cell proliferation. Confluent preadipocytes were subjected into heat shock procedure, recovery and then AGN treatment prior to stimulation with the differentiation solution. Heat shocked preadipocytes exhibited reduced differentiation as supported by decreased amount of lipid accumulation in Oil Red O staining and triglyceride measurement. However, those heat shocked preadipocytes that then were given AGN extract showed a dose dependent increase in lipid accumulation as shown by both evaluation procedures. In line with these results, real-time polymerase chain reaction (RT-PCR and Western blot analysis showed that AGN increased adipogenic differentiation by upregulating heat shock protection related genes and proteins together with the adipogenic markers. These findings imply the potential of

  12. Resveratrol Reactivates Latent HIV through Increasing Histone Acetylation and Activating Heat Shock Factor 1.

    Science.gov (United States)

    Zeng, Xiaoyun; Pan, Xiaoyan; Xu, Xinfeng; Lin, Jian; Que, Fuchang; Tian, Yuanxin; Li, Lin; Liu, Shuwen

    2017-06-07

    The persistence of latent HIV reservoirs presents a significant challenge to viral eradication. Effective latency reversing agents (LRAs) based on "shock and kill" strategy are urgently needed. The natural phytoalexin resveratrol has been demonstrated to enhance HIV gene expression, although its mechanism remains unclear. In this study, we demonstrated that resveratrol was able to reactivate latent HIV without global T cell activation in vitro. Mode of action studies showed resveratrol-mediated reactivation from latency did not involve the activation of silent mating type information regulation 2 homologue 1 (SIRT1), which belonged to class-3 histone deacetylase (HDAC). However, latent HIV was reactivated by resveratrol mediated through increasing histone acetylation and activation of heat shock factor 1 (HSF1). Additionally, synergistic activation of the latent HIV reservoirs was observed under cotreatment with resveratrol and conventional LRAs. Collectively, this research reveals that resveratrol is a natural LRA and shows promise for HIV therapy.

  13. The influence of state-to-state kinetics on diffusion and heat transfer behind shock waves

    Energy Technology Data Exchange (ETDEWEB)

    Kunova, O.; Kustova, E.; Mekhonoshina, M.; Nagnibeda, E. [Saint Petersburg State University, 198504, Universitetskiy pr., 28, Saint Petersburg (Russian Federation)

    2014-12-09

    In the paper, the influence of vibrational and chemical kinetics on heat transfer and diffusion in hypersonic flows of N{sub 2}/N mixture in the relaxation zone behind shock waves is studied on the basis of the state-to-state kinetic theory approach. The results of calculations of vibrational level populations ni, gas temperature T, total energy flux q, diffusion velocities of molecules at different vibrational states V{sub i} and atoms V{sub a} in the relaxation zone behind a shock front are presented for the free stream Mach number M = 10, 15. The contribution of different dissipative processes to the total energy flux is estimated for various flow conditions. The impact of non-equilibrium vibrational distributions in the free stream on molecular level populations and transport properties in the relaxation zone is shown.

  14. Electron Heating, Magnetic Field Amplification, and Cosmic Ray Precursor Length at Supernova Remnant Shocks

    CERN Document Server

    Laming, J Martin; Ghavamian, Parviz; Rakowski, Cara

    2014-01-01

    We investigate the observability, by direct and indirect means, of a shock precursor arising from magnetic field amplification by cosmic rays. We estimate the depth of such a precursor under conditions of nonresonant amplification, which can provide magnetic field strengths comparable to those inferred for supernova remnants. Magnetic field generation occurs as the streaming cosmic rays induce a plasma return current, and may be quenched either by nonresonant or resonant channels. In the case of nonresonant saturation, the cosmic rays become magnetized and amplification saturates at higher magnetic fields. The precursor can extend out to $10^{17} - 10^{18}$ cm and is potentially detectable. If resonant saturation occurs, the cosmic rays are scattered by turbulence and the precursor length will likely be much smaller. The dependence of precursor length on shock velocity has implications for electron heating. In the case of resonant saturation, this dependence is similar to that in the more familiar resonantly ...

  15. Association of coral algal symbionts with a diverse viral community responsive to heat shock

    KAUST Repository

    Brüwer, Jan D.

    2017-08-17

    Stony corals provide the structural foundation of coral reef ecosystems and are termed holobionts given they engage in symbioses, in particular with photosynthetic dinoflagellates of the genus Symbiodinium. Besides Symbiodinium, corals also engage with bacteria affecting metabolism, immunity, and resilience of the coral holobiont, but the role of associated viruses is largely unknown. In this regard, the increase of studies using RNA sequencing (RNA-Seq) to assess gene expression provides an opportunity to elucidate viral signatures encompassed within the data via careful delineation of sequence reads and their source of origin.Here, we re-analyzed an RNA-Seq dataset from a cultured coral symbiont (Symbiodinium microadriaticum, Clade A1) across four experimental treatments (control, cold shock, heat shock, dark shock) to characterize associated viral diversity, abundance, and gene expression. Our approach comprised the filtering and removal of host sequence reads, subsequent phylogenetic assignment of sequence reads of putative viral origin, and the assembly and analysis of differentially expressed viral genes. About 15.46% (123 million) of all sequence reads were non-host-related, of which <1% could be classified as archaea, bacteria, or virus. Of these, 18.78% were annotated as virus and comprised a diverse community consistent across experimental treatments. Further, non-host related sequence reads assembled into 56,064 contigs, including 4856 contigs of putative viral origin that featured 43 differentially expressed genes during heat shock. The differentially expressed genes included viral kinases, ubiquitin, and ankyrin repeat proteins (amongst others), which are suggested to help the virus proliferate and inhibit the algal host\\'s antiviral response.Our results suggest that a diverse viral community is associated with coral algal endosymbionts of the genus Symbiodinium, which prompts further research on their ecological role in coral health and resilience.

  16. Similarity solution for a cylindrical shock wave in a rotational axisymmetric dusty gas with heat conduction and radiation heat flux

    Science.gov (United States)

    Vishwakarma, J. P.; Nath, G.

    2012-01-01

    The propagation of shock waves in a rotational axisymmetric dusty gas with heat conduction and radiation heat flux, which has a variable azimuthally fluid velocity together with a variable axial fluid velocity, is investigated. The dusty gas is assumed to be a mixture of non-ideal (or perfect) gas and small solid particles, in which solid particles are continuously distributed. It is assumed that the equilibrium flow-condition is maintained and variable energy input is continuously supplied by the piston (or inner expanding surface). The fluid velocities in the ambient medium are assume to be vary and obey power laws. The density of the ambient medium is assumed to be constant, the heat conduction is express in terms of Fourier's law and the radiation is considered to be of the diffusion type for an optically thick grey gas model. The thermal conductivity K and the absorption coefficient αR are assumed to vary with temperature and density. In order to obtain the similarity solutions the angular velocity of the ambient medium is assume to be decreasing as the distance from the axis increases. The effects of the variation of the heat transfer parameter and non-idealness of the gas in the mixture are investigated. The effects of an increase in (i) the mass concentration of solid particles in the mixture and (ii) the ratio of the density of solid particles to the initial density of the gas on the flow variables are also investigated.

  17. Binding of natural and synthetic inhibitors to human heat shock protein 90 and their clinical application.

    Science.gov (United States)

    Petrikaitė, Vilma; Matulis, Daumantas

    2011-01-01

    This review describes the recent progress in the field of heat shock protein 90 (Hsp90) inhibitor design. Hsp90 is a heat shock protein with a molecular weight of approximately 90 kDa. Hsp90 is considered a good anticancer target because its inhibition leads to inactivation of its numerous client proteins participating in various signaling and other processes involved in cancer progression. Numerous Hsp90 inhibitors-leads currently tested in clinical trials are presented in this review. Furthermore, this review emphasizes the application of biophysical binding assays in the development of Hsp90 inhibitors. The binding of designed lead compounds to various Hsp90 constructs is measured by isothermal titration calorimetry and thermal shift assay. These assays provide a detailed energetic insight of the binding reaction, including the enthalpy, entropy, heat capacity, and the Gibbs free energy. A detailed description of the binding energetics helps to extend our knowledge of structure-activity relationships in the design of more potent inhibitors. The most active compounds are then tested for their absorption, distribution, metabolism, elimination, toxicity, and activity against cancer cell lines.

  18. HIFI observations of warm gas in DR21: Shock versus radiative heating

    CERN Document Server

    Ossenkopf, V; Simon, R; Schneider, N; Okada, Y; Stutzki, J; Gerin, M; Akyilmaz, M; Beintema, D; Benz, A O; Berne, O; Boulanger, F; Bumble, B; Coeur-Joly, O; Dedes, C; Diez-Gonzalez, M C; France, K; Fuente, A; Gallego, J D; Goicoechea, J R; Güsten, R; Harris, A; Higgins, R; Jackson, B; Jarchow, C; Joblin, C; Klein, T; Kramer, C; Lord, S; Martin, P; Martin-Pintado, J; Mookerjea, B; Neufeld, D A; Phillips, T; Rizzo, J R; van der Tak, F F S; Teyssier, D; Yorke, H

    2010-01-01

    The molecular gas in the DR21 massive star formation region is known to be affected by the strong UV field from the central star cluster and by a fast outflow creating a bright shock. The relative contribution of both heating mechanisms is the matter of a long debate. By better sampling the excitation ladder of various tracers we provide a quantitative distinction between the different heating mechanisms. HIFI observations of mid-J transitions of CO and HCO+ isotopes allow us to bridge the gap in excitation energies between observations from the ground, characterizing the cooler gas, and existing ISO LWS spectra, constraining the properties of the hot gas. Comparing the detailed line profiles allows to identify the physical structure of the different components. In spite of the known shock-excitation of H2 and the clearly visible strong outflow, we find that the emission of all lines up to > 2 THz can be explained by purely radiative heating of the material. However, the new Herschel/HIFI observations reveal ...

  19. Tissue Erosion Using Shock Wave Heating and Millisecond Boiling in HIFU Fields

    Science.gov (United States)

    Canney, Michael S.; Khokhlova, Tatiana D.; Khokhlova, Vera A.; Bailey, Michael R.; Ha Hwang, Joo; Crum, Lawrence A.

    2010-03-01

    A wide variety of treatment protocols have been employed in high intensity focused ultrasound (HIFU) treatments, and the resulting bioeffects observed include both mechanical as well as thermal effects. In recent studies, there has been significant interest in generating purely mechanical damage using protocols with short, microsecond pulses. Tissue erosion effects have been attained by operating HIFU sources using short pulses of 10-20 cycles, low duty cycles (<1%), and pulse average intensities of greater than 20 kW/cm2. The goal of this work was to use a modified pulsing protocol, consisting of longer, millisecond-long pulses of ultrasound and to demonstrate that heating and rapid millisecond boiling from shock wave formation can be harnessed to induce controlled mechanical destruction of soft tissue. Experiments were performed in excised bovine liver and heart tissue using a 2-MHz transducer. Boiling activity was monitored during exposures using a high voltage probe in parallel with the HIFU source. In situ acoustic fields and heating rates were determined for exposures using a novel derating approach for nonlinear HIFU fields. Several different exposure protocols were used and included varying the duty cycle, pulse length, and power to the source. After exposures, the tissue was sectioned, and the gross lesion morphology was observed. Different types of lesions were induced in experiments that ranged from purely thermal to purely mechanical depending on the pulsing protocol used. Therefore, shock wave heating and millisecond boiling may be an effective method for reliably generating significant tissue erosion effects.

  20. Heat transfer and wall temperature effects in shock wave turbulent boundary layer interactions

    CERN Document Server

    Bernardini, Matteo; Pirozzoli, Sergio; Grasso, Francesco

    2016-01-01

    Direct numerical simulations are carried out to investigate the effect of the wall temperature on the behavior of oblique shock-wave/turbulent boundary layer interactions at freestream Mach number $2.28$ and shock angle of the wedge generator $\\varphi = 8^{\\circ}$. Five values of the wall-to-recovery-temperature ratio ($T_w/T_r$) are considered, corresponding to cold, adiabatic and hot wall thermal conditions. We show that the main effect of cooling is to decrease the characteristic scales of the interaction in terms of upstream influence and extent of the separation bubble. The opposite behavior is observed in the case of heating, that produces a marked dilatation of the interaction region. The distribution of the Stanton number shows that a strong amplification of the heat transfer occurs across the interaction, and the maximum values of thermal and dynamic loads are found in the case of cold wall. The analysis reveals that the fluctuating heat flux exhibits a strong intermittent behavior, characterized by ...

  1. The heat-shock protein/chaperone network and multiple stress resistance.

    Science.gov (United States)

    Jacob, Pierre; Hirt, Heribert; Bendahmane, Abdelhafid

    2017-04-01

    Crop yield has been greatly enhanced during the last century. However, most elite cultivars are adapted to temperate climates and are not well suited to more stressful conditions. In the context of climate change, stress resistance is a major concern. To overcome these difficulties, scientists may help breeders by providing genetic markers associated with stress resistance. However, multistress resistance cannot be obtained from the simple addition of single stress resistance traits. In the field, stresses are unpredictable and several may occur at once. Consequently, the use of single stress resistance traits is often inadequate. Although it has been historically linked with the heat stress response, the heat-shock protein (HSP)/chaperone network is a major component of multiple stress responses. Among the HSP/chaperone 'client proteins', many are primary metabolism enzymes and signal transduction components with essential roles for the proper functioning of a cell. HSPs/chaperones are controlled by the action of diverse heat-shock factors, which are recruited under stress conditions. In this review, we give an overview of the regulation of the HSP/chaperone network with a focus on Arabidopsis thaliana. We illustrate the role of HSPs/chaperones in regulating diverse signalling pathways and discuss several basic principles that should be considered for engineering multiple stress resistance in crops through the HSP/chaperone network. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  2. An efficient procedure for purification of recombinant human β heat shock protein 90

    Directory of Open Access Journals (Sweden)

    M Bandehpour

    2010-03-01

    Full Text Available "nBackground and the purpose of the study: Heat Shock Protein 90 (Hsp90 is typically the most abundant chaperone in the eukaryotic cell cytoplasm, and its expression is essential for loading immunogenic peptides onto major histocompatibility complex molecules for presentation to T-cells. Therefore, it may act as a good candidate as an adjuvant molecule in vaccine technology. "n Methods: Initially the human Hsp90β gene was cloned into the heat inducible expression vector pGP1-2 and then the recombinant protein was isolated by ion exchange chromatography. After intradermal injection of confirmed purified band of protein to rabbits and isolation of the serum IgG antibody, for its affinity purification, the rabbit’s purified Hsp90 specific IgG was coupled to the cyanogen bromide-activated Sepharose 4B. Results: The recovery of the purified protein of interest by affinity chromatography was 50% . "n "nConclusion: This research enabled purification of human heat shock protein by a laboratory "n "nprepared column chromatography. "n   

  3. A novel protein quality control mechanism contributes to heat shock resistance of worldwide-distributed Pseudomonas aeruginosa clone C strains.

    Science.gov (United States)

    Lee, Changhan; Wigren, Edvard; Trček, Janja; Peters, Verena; Kim, Jihong; Hasni, Muhammad Sharif; Nimtz, Manfred; Lindqvist, Ylva; Park, Chankyu; Curth, Ute; Lünsdorf, Heinrich; Römling, Ute

    2015-11-01

    Pseudomonas aeruginosa is a highly successful nosocomial pathogen capable of causing a wide variety of infections with clone C strains most prevalent worldwide. In this study, we initially characterize a molecular mechanism of survival unique to clone C strains. We identified a P. aeruginosa clone C-specific genomic island (PACGI-1) that contains the highly expressed small heat shock protein sHsp20c, the founding member of a novel subclass of class B bacterial small heat shock proteins. sHsp20c and adjacent gene products are involved in resistance against heat shock. Heat stable sHsp20c is unconventionally expressed in stationary phase in a wide temperature range from 20 to 42°C. Purified sHsp20c has characteristic features of small heat shock protein class B as it is monodisperse, forms sphere-like 24-meric oligomers and exhibits significant chaperone activity. As the P. aeruginosa clone C population is significantly more heat shock resistant than genetically unrelated P. aeruginosa strains without sHsp20c, the horizontally acquired shsp20c operon might contribute to the survival of worldwide-distributed clone C strains.

  4. INDUCIBLE HEAT SHOCK PROTEIN (HSP70-1) PROTECTS MCF-7 CELLS FROM THE CYTOTOXIC AND GENOTOXIC EFFECTS OF ARSENITE

    Science.gov (United States)

    Heat shock proteins (HSPs) belong to the highly conserved family of stress proteins and are induced following exposure to arsenic. Elevated HSPs protect against cellular damage from heat but it is unclear wether HSP induction alters the damaging effects of environmental chemical ...

  5. INDUCIBLE HEAT SHOCK PROTEIN (HSP70-1) PROTECTS MCF-7 CELLS FROM THE CYTOTOXIC AND GENOTOXIC EFFECTS OF ARSENITE

    Science.gov (United States)

    Heat shock proteins (HSPs) belong to the highly conserved family of stress proteins and are induced following exposure to arsenic. Elevated HSPs protect against cellular damage from heat but it is unclear wether HSP induction alters the damaging effects of environmental chemical ...

  6. The importance of seed mass for the tolerance to heat shocks of savanna and forest tree species

    NARCIS (Netherlands)

    Ribeiro, L.C.; Barbosa, E.R.M.; Langevelde, van F.; Borghetti, F.

    2015-01-01

    Questions: Does seed mass influence the tolerance of seeds to the effects of heating in fires? Is the tolerance to heat shocks during fire events dependent mostly on seed mass itself or to other traits linked to the species ecological origin, e.g. non-fire-prone (forest) and fire-prone (savanna) env

  7. Mapping temperature-induced conformational changes in the Escherichia coli heat shock transcription factor sigma 32 by amide hydrogen exchange

    DEFF Research Database (Denmark)

    Rist, Wolfgang; Jørgensen, Thomas J D; Roepstorff, Peter;

    2003-01-01

    gene transcription. To investigate possible heat-induced conformational changes in sigma 32 we performed amide hydrogen (H/D) exchange experiments under optimal growth and heat shock conditions combined with mass spectrometry. We found a rapid exchange of around 220 of the 294 amide hydrogens at 37...... degrees C, indicating that sigma 32 adopts a highly flexible structure. At 42 degrees C we observed a slow correlated exchange of 30 additional amide hydrogens and localized it to a helix-loop-helix motif within domain sigma 2 that is responsible for the recognition of the -10 region in heat shock...

  8. Interaction of small heat shock proteins with light component of neurofilaments (NFL).

    Science.gov (United States)

    Nefedova, Victoria V; Sudnitsyna, Maria V; Gusev, Nikolai B

    2017-07-01

    The interaction of human small heat shock protein HspB1, its point mutants associated with distal hereditary motor neuropathy, and three other small heat shock proteins (HspB5, HspB6, HspB8) with the light component of neurofilaments (NFL) was analyzed by differential centrifugation, analytical ultracentrifugation, and fluorescent spectroscopy. The wild-type HspB1 decreased the quantity of NFL in pellets obtained after low- and high-speed centrifugation and increased the quantity of NFL remaining in the supernatant after high-speed centrifugation. Part of HspB1 was detected in the pellet of NFL after high-speed centrifugation, and at saturation, 1 mol of HspB1 monomer was bound per 2 mol of NFL. Point mutants of HspB1 associated with distal hereditary motor neuropathy (G84R, L99M, R140G, K141Q, and P182S) were almost as effective as the wild-type HspB1 in modulation of NFL assembly. At low ionic strength, HspB1 weakly interacted with NFL tetramers, and this interaction was increased upon salt-induced polymerization of NFL. HspB1 and HspB5 (αB-crystallin) decreased the rate of NFL polymerization measured by fluorescent spectroscopy. HspB6 (Hsp20) and HspB8 (Hsp22) were less effective than HspB1 (or HspB5) in modulation of NFL assembly. The data presented indicate that the small heat shock proteins affect NFL transition from tetramers to filaments, hydrodynamic properties of filaments, and their bundling and therefore probably modulate the formation of intermediate filament networks in neurons.

  9. Effects of disruption of heat shock genes on susceptibility of Escherichia coli to fluoroquinolones

    Science.gov (United States)

    Yamaguchi, Yuko; Tomoyasu, Toshifumi; Takaya, Akiko; Morioka, Mizue; Yamamoto, Tomoko

    2003-01-01

    Background It is well known that expression of certain bacterial genes responds rapidly to such stimuli as exposure to toxic chemicals and physical agents. It is generally believed that the proteins encoded in these genes are important for successful survival of the organism under the hostile conditions. Analogously, the proteins induced in bacterial cells exposed to antibiotics are believed to affect the organisms' susceptibility to these agents. Results We demonstrated that Escherichia coli cells exposed to levofloxacin (LVFX), a fluoroquinolone (FQ), induce the syntheses of heat shock proteins and RecA. To examine whether the heat shock proteins affect the bactericidal action of FQs, we constructed E. coli strains with mutations in various heat shock genes and tested their susceptibility to FQs. Mutations in dnaK, groEL, and lon increased this susceptibility; the lon mutant exhibited the greatest effects. The increased susceptibility of the lon mutant was corroborated by experiments in which the gene encoding the cell division inhibitor, SulA, was subsequently disrupted. SulA is induced by the SOS response and degraded by the Lon protease. The findings suggest that the hypersusceptibility of the lon mutant to FQs could be due to abnormally high levels of SulA protein resulting from the depletion of Lon and the continuous induction of the SOS response in the presence of FQs. Conclusion The present results show that the bactericidal action of FQs is moderately affected by the DnaK and GroEL chaperones and strongly affected by the Lon protease. FQs have contributed successfully to the treatment of various bacterial infections, but their widespread use and often misuse, coupled with emerging resistance, have gradually compromised their utility. Our results suggest that agents capable of inhibiting the Lon protease have potential for combination therapy with FQs. PMID:12911840

  10. Heat shock increases lifetime of a small RNA and induces its accumulation in cells.

    Science.gov (United States)

    Tatosyan, Karina A; Kramerov, Dmitri A

    2016-08-01

    4.5SH and 4.5SI RNA are two abundant small non-coding RNAs specific for several related rodent families including Muridae. These RNAs have a number of common characteristics such as the short length (about 100nt), transcription by RNA polymerase III, and origin from Short Interspersed Elements (SINEs). However, their stabilities in cells substantially differ: the half-life of 4.5SH RNA is about 20min, while that of 4.5SI RNA is 22h. Here we studied the influence of cell stress such as heat shock or viral infection on these two RNAs. We found that the level of 4.5SI RNA did not change in stressed cells; whereas heat shock increased the abundance of 4.5SH RNA 3.2-10.5 times in different cell lines; and viral infection, 5 times. Due to the significant difference in the turnover rates of these two RNAs, a similar activation of their transcription by heat shock increases the level of the short-lived 4.5SH RNA and has minor effect on the level of the long-lived 4.5SI RNA. In addition, the accumulation of 4.5SH RNA results not only from the induction of its transcription but also from a substantial retardation of its decay. To our knowledge, it is the first example of a short-lived non-coding RNA whose elongated lifetime contributes significantly to its accumulation in stressed cells.

  11. The small heat shock proteins from Acidithiobacillus ferrooxidans: gene expression, phylogenetic analysis, and structural modeling

    Directory of Open Access Journals (Sweden)

    Ribeiro Daniela A

    2011-12-01

    Full Text Available Abstract Background Acidithiobacillus ferrooxidans is an acidophilic, chemolithoautotrophic bacterium that has been successfully used in metal bioleaching. In this study, an analysis of the A. ferrooxidans ATCC 23270 genome revealed the presence of three sHSP genes, Afe_1009, Afe_1437 and Afe_2172, that encode proteins from the HSP20 family, a class of intracellular multimers that is especially important in extremophile microorganisms. Results The expression of the sHSP genes was investigated in A. ferrooxidans cells submitted to a heat shock at 40°C for 15, 30 and 60 minutes. After 60 minutes, the gene on locus Afe_1437 was about 20-fold more highly expressed than the gene on locus Afe_2172. Bioinformatic and phylogenetic analyses showed that the sHSPs from A. ferrooxidans are possible non-paralogous proteins, and are regulated by the σ32 factor, a common transcription factor of heat shock proteins. Structural studies using homology molecular modeling indicated that the proteins encoded by Afe_1009 and Afe_1437 have a conserved α-crystallin domain and share similar structural features with the sHSP from Methanococcus jannaschii, suggesting that their biological assembly involves 24 molecules and resembles a hollow spherical shell. Conclusion We conclude that the sHSPs encoded by the Afe_1437 and Afe_1009 genes are more likely to act as molecular chaperones in the A. ferrooxidans heat shock response. In addition, the three sHSPs from A. ferrooxidans are not recent paralogs, and the Afe_1437 and Afe_1009 genes could be inherited horizontally by A. ferrooxidans.

  12. Identification and functional characterization of heat shock transcription factor1 in Litopenaeus vannamei.

    Science.gov (United States)

    Yan, Hui; Zhang, Shuang; Li, Xiao-Yun; Yuan, Feng-Hua; Qiu, Wei; Chen, Yong-Gui; Weng, Shao-Ping; He, Jian-Guo; Chen, Yi-Hong

    2014-03-01

    Heat shock transcription factors belong to the heat shock factor (HSF) protein family, which are involved in heat shock protein (HSP) gene regulation. They are critical for cell survival upon exposure to harmful conditions. In this study, we identified and characterized a HSF1 (LvHSF1) gene in Litopenaeus vannamei, with a full-length cDNA of 2841 bp and an open reading frame encoding a putative protein of 632 amino acids. Through multiple sequence alignment and phylogenetic analysis, it was revealed that LvHSF1 was closed to insect HSF family, which contained a highly conserved DNA-binding domain, oligomerization domains with HR-A/B, and a nuclear localization signal. Tissues distribution showed that LvHSF1 was widely expressed in all tissues tested. And it was upregulated in hemocytes and gills after Vibrio alginolyticus or Staphylococcus aureus infection. Dual-luciferase reporter assays indicated that LvHSF1 activated the promoters of L. vannamei HSP70 (LvHSP70) and L. vannamei Cactus (LvCactus), while inhibited the expressions of Drosophila antimicrobial peptide (AMP) Atta, Mtk, and L. vannamei AMP PEN4 through NF-κB signal transduction pathway modification. Knocked-down expression of LvHSF1 by dsRNA resulted in downregulations of LvHSP70 and LvCactus, as well as cumulative mortality decreasing under V. alginolyticus or S. aureus infection in L. vannamei. Taken together, our data strongly suggest that LvHSF1 is involved in LvHSP70 regulation, therefore plays a great role in stress resistance. And it also takes part in LvCactus/LvDorsal feedback regulatory pathway modification of L. vannamei, which is in favor of V. alginolyticus or S. aureus infection.

  13. Ste20-like kinase, SLK, activates the heat shock factor 1 - Hsp70 pathway.

    Science.gov (United States)

    Cybulsky, Andrey V; Guillemette, Julie; Papillon, Joan

    2016-09-01

    Expression and activation of SLK increases during renal ischemia-reperfusion injury. When highly expressed, SLK signals via c-Jun N-terminal kinase and p38 to induce apoptosis, and it exacerbates apoptosis induced by ischemia-reperfusion injury. Overexpression of SLK in glomerular epithelial cells (GECs)/podocytes in vivo induces injury and proteinuria. In response to various stresses, cells enhance expression of chaperones or heat shock proteins (e.g. Hsp70), which are involved in the folding and maturation of newly synthesized proteins, and can refold denatured or misfolded proteins. We address the interaction of SLK with the heat shock factor 1 (HSF1)-Hsp70 pathway. Increased expression of SLK in GECs (following transfection) induced HSF1 transcriptional activity. Moreover, HSF1 transcriptional activity was increased by in vitro ischemia-reperfusion injury (chemical anoxia/recovery) and heat shock, and in both instances was amplified further by SLK overexpression. HSF1 binds to promoters of target genes, such as Hsp70 and induces their transcription. By analogy to HSF1, SLK stimulated Hsp70 expression. Hsp70 was also enhanced by anoxia/recovery and was further amplified by SLK overexpression. Induction of HSF1 and Hsp70 was dependent on the kinase activity of SLK, and was mediated via polo-like kinase-1. Transfection of constitutively active HSF1 enhanced Hsp70 expression and inhibited SLK-induced apoptosis. Conversely, the proapoptotic action of SLK was augmented by HSF1 shRNA, or the Hsp70 inhibitor, pifithrin-μ. In conclusion, increased expression/activity of SLK activates the HSF1-Hsp70 pathway. Hsp70 attenuates the primary proapoptotic effect of SLK. Modulation of chaperone expression may potentially be harnessed as cytoprotective therapy in renal cell injury.

  14. Effects of disruption of heat shock genes on susceptibility of Escherichia coli to fluoroquinolones

    Directory of Open Access Journals (Sweden)

    Morioka Mizue

    2003-08-01

    Full Text Available Abstract Background It is well known that expression of certain bacterial genes responds rapidly to such stimuli as exposure to toxic chemicals and physical agents. It is generally believed that the proteins encoded in these genes are important for successful survival of the organism under the hostile conditions. Analogously, the proteins induced in bacterial cells exposed to antibiotics are believed to affect the organisms' susceptibility to these agents. Results We demonstrated that Escherichia coli cells exposed to levofloxacin (LVFX, a fluoroquinolone (FQ, induce the syntheses of heat shock proteins and RecA. To examine whether the heat shock proteins affect the bactericidal action of FQs, we constructed E. coli strains with mutations in various heat shock genes and tested their susceptibility to FQs. Mutations in dnaK, groEL, and lon increased this susceptibility; the lon mutant exhibited the greatest effects. The increased susceptibility of the lon mutant was corroborated by experiments in which the gene encoding the cell division inhibitor, SulA, was subsequently disrupted. SulA is induced by the SOS response and degraded by the Lon protease. The findings suggest that the hypersusceptibility of the lon mutant to FQs could be due to abnormally high levels of SulA protein resulting from the depletion of Lon and the continuous induction of the SOS response in the presence of FQs. Conclusion The present results show that the bactericidal action of FQs is moderately affected by the DnaK and GroEL chaperones and strongly affected by the Lon protease. FQs have contributed successfully to the treatment of various bacterial infections, but their widespread use and often misuse, coupled with emerging resistance, have gradually compromised their utility. Our results suggest that agents capable of inhibiting the Lon protease have potential for combination therapy with FQs.

  15. New Evidence for Efficient Collisionless Heating of Electrons at the Reverse Shock of a Young Supernova Remnant

    Science.gov (United States)

    Yamaguchi, Hiroya; Eriksen, Kristoffer A.; Badenes, Carles; Hughes, John P.; Brickhouse, Nancy S.; Foster, Adam R.; Patnaude, Daniel J.; Petre, Robert; Slane, Patrick O.; Smith, Randall K.

    2013-01-01

    Although collisionless shocks are ubiquitous in astrophysics, certain key aspects of them are not well understood. In particular, the process known as collisionless electron heating, whereby electrons are rapidly energized at the shock front, is one of the main open issues in shock physics. Here, we present the first clear evidence for efficient collisionless electron heating at the reverse shock of Tycho's supernova remnant (SNR), revealed by Fe K diagnostics using high-quality X-ray data obtained by the Suzaku satellite. We detect K beta (3p yields 1s) fluorescence emission from low-ionization Fe ejecta excited by energetic thermal electrons at the reverse shock front, which peaks at a smaller radius than Fe K alpha (2p yields 1s) emission dominated by a relatively highly ionized component. Comparisons with our hydrodynamical simulations imply instantaneous electron heating to a temperature 1000 times higher than expected from Coulomb collisions alone. The unique environment of the reverse shock, which is propagating with a high Mach number into rarefied ejecta with a low magnetic field strength, puts strong constraints on the physical mechanism responsible for this heating and favors a cross-shock potential created by charge deflection at the shock front. Our sensitive observation also reveals that the reverse shock radius of this SNR is about 10% smaller than the previous measurement using the Fe K alpha morphology from the Chandra observations. Since strong Fe K beta fluorescence is expected only from low-ionization plasma where Fe ions still have many 3p electrons, this feature is key to diagnosing the plasma state and distribution of the immediate postshock ejecta in a young SNR.

  16. Effect of Heat Shock Treatment and Aloe Vera Coating to Chilling Injury Symptom in Tomato (Lycopersicon asculantum Mill.

    Directory of Open Access Journals (Sweden)

    Sutrisno

    2012-04-01

    Full Text Available This research was undertaken to determine the effect of length in heat shock and edible coating as pre-storage treatment to Chilling Injury (CI symptom reflected by ion leakage induced and quality properties in tomato (Lycopersicon asculantum Mill.. Heat Shock Treatment (HST was conducted at three different levels of length, which were, 20; 40 and 60 min. Edible coating was conducted using aloe vera gel. The result showed that HST and Aloe Vera Coating (AVC were more effective to reduce CI symptom at lower chilling storage. Prolong exposure to heated water may delay climacteric peak. The length of heat shock, AVC treatment and low temperature storage significantly affected the tomato quality parameter but not significantly different for each treatment except weight loss. HST for 20 min at ambient temperature was significantly different to other treatment.

  17. Heat shock inhibition of CDK5 increases NOXA levels through miR-23a repression.

    Science.gov (United States)

    Morey, Trevor M; Roufayel, Rabih; Johnston, Donald S; Fletcher, Andrew S; Mosser, Dick D

    2015-05-01

    Hyperthermia is a proteotoxic stress that is lethal when exposure is extreme but also cytoprotective in that sublethal exposure leads to the synthesis of heat shock proteins, including HSP70, which are able to inhibit stress-induced apoptosis. CDK5 is an atypical cyclin-dependent kinase family member that regulates many cellular functions including motility and survival. Here we show that exposure of a human lymphoid cell line to hyperthermia causes CDK5 insolubilization and loss of tyrosine-15 phosphorylation, both of which were prevented in cells overexpressing HSP70. Inhibition of CDK5 activity with roscovitine-sensitized cells to heat induced apoptosis indicating a protective role for CDK5 in inhibiting heat-induced apoptosis. Both roscovitine and heat shock treatment caused increased accumulation of NOXA a pro-apoptotic BH3-only member of the BCL2 family. The increased abundance of NOXA by CDK5 inhibition was not a result of changes in NOXA protein turnover. Instead, CDK5 inhibition increased NOXA mRNA and protein levels by decreasing the expression of miR-23a, whereas overexpressing the CDK5 activator p35 attenuated both of these effects on NOXA and miR-23a expression. Lastly, overexpression of miR-23a prevented apoptosis under conditions in which CDK5 activity was inhibited. These results demonstrate that CDK5 activity provides resistance to heat-induced apoptosis through the expression of miR-23a and subsequent suppression of NOXA synthesis. Additionally, they indicate that hyperthermia induces apoptosis through the insolubilization and inhibition of CDK5 activity.

  18. Analysis of phosphorylation of human heat shock factor 1 in cells experiencing a stress

    Directory of Open Access Journals (Sweden)

    Lane William S

    2005-03-01

    Full Text Available Abstract Background Heat shock factor (HSF/HSF1 not only is the transcription factor primarily responsible for the transcriptional response of cells to physical and chemical stress but also coregulates other important signaling pathways. The factor mediates the stress-induced expression of heat shock or stress proteins (HSPs. HSF/HSF1 is inactive in unstressed cells and is activated during stress. Activation is accompanied by hyperphosphorylation of the factor. The regulatory importance of this phosphorylation has remained incompletely understood. Several previous studies on human HSF1 were concerned with phosphorylation on Ser303, Ser307 and Ser363, which phosphorylation appears to be related to factor deactivation subsequent to stress, and one study reported stress-induced phosphorylation of Ser230 contributing to factor activation. However, no previous study attempted to fully describe the phosphorylation status of an HSF/HSF1 in stressed cells and to systematically identify phosphoresidues involved in factor activation. The present study reports such an analysis for human HSF1 in heat-stressed cells. Results An alanine scan of all Ser, Thr and Tyr residues of human HSF1 was carried out using a validated transactivation assay, and residues phosphorylated in HSF1 were identified by mass spectrometry and sequencing. HSF1 activated by heat treatment was phosphorylated on Ser121, Ser230, Ser292, Ser303, Ser307, Ser314, Ser319, Ser326, Ser344, Ser363, Ser419, and Ser444. Phosphorylation of Ser326 but none of the other Ser residues was found to contribute significantly to activation of the factor by heat stress. Phosphorylation on Ser326 increased rapidly during heat stress as shown by experiments using a pSer326 phosphopeptide antibody. Heat stress-induced DNA binding and nuclear translocation of a S326A substitution mutant was not impaired in HSF1-negative cells, but the mutant stimulated HSP70 expression several times less well than wild type

  19. Members of the heat-shock protein 70 family promote cancer cell growth by distinct mechanisms

    DEFF Research Database (Denmark)

    Rohde, Mikkel; Daugaard, Mads; Jensen, Mette Hartvig;

    2005-01-01

    Whereas the stress-inducible heat-shock protein 70 (Hsp70) has gained plenty of attention as a putative target for tumor therapy, little is known about the role of other Hsp70 proteins in cancer. Here we present the first thorough analysis of the expression and function of the cytosolic Hsp70...... the survival of tumorigenic as well as nontumorigenic cells depended on Hsc70. Cancer cells depleted for Hsp70 and Hsp70-2 displayed strikingly different morphologies (detached and round vs. flat senescent-like), cell cycle distributions (G2/M vs. G1 arrest) and gene expression profiles. Only Hsp70-2 depletion...

  20. Chronic SIV and morphine treatment increases heat shock protein 5 expression at the synapse.

    Science.gov (United States)

    Pendyala, Gurudutt; Periyasamy, Palsamy; Callen, Shannon; Fox, Howard S; Lisco, Steven J; Buch, Shilpa J

    2015-10-01

    The abuse of opiates such as morphine in synergy with HIV infection accelerates neurocognitive impairments and neuropathology in the CNS of HIV-infected subjects, collectively referred to as HAND. To identify potential pathogenic markers associated with HIV and morphine in perturbing the synaptic architecture, we performed quantitative mass spectrometry proteomics on purified synaptosomes isolated from the caudate of two groups of rhesus macaques chronically infected with SIV differing by one regimen-morphine treatment. The upregulation of heat shock 70-kDa protein 5 in the SIV + morphine group points to increased cellular stress during SIV/morphine interaction thus leading to CNS dysfunction.

  1. Heat Shock Protein translocation induced by membrane fluidization increases tumor-cell sensitivity to chemotherapeutic drugs.

    Science.gov (United States)

    Dempsey, Nina C; Ireland, H Elyse; Smith, Carly M; Hoyle, Christine F; Williams, John H H

    2010-10-28

    Treatment of chronic lymphocytic leukemia (CLL) remains a challenge due to the frequency of drug resistance amongst patients. Improving the delivery of chemotherapeutic agents while reducing the expression of anti-apoptotic Heat Shock Proteins (HSPs) within the cancer cells may facilitate in overcoming this drug resistance. We demonstrate for the first time that sub-lethal doses of chemotherapeutic agents can be combined with membrane fluidizing treatments to produce a significant increase in drug efficacy and apoptosis in vitro. We show that fluidizers result in a transient decrease in intracellular HSPs, resulting in increased tumor-cell sensitivity and a membrane-associated induction of HSP gene expression.

  2. Heat transfer analysis for the roller shell under the condition of periodic thermal shock

    Institute of Scientific and Technical Information of China (English)

    Lihua Zhan; Xiaoqian Li

    2003-01-01

    According to the actual working conditions of roller shell in the process of continuous roll casting, the Fourier heat transfer law is used to conduct the simulating analysis for the temperature distribution of the roller shell under the condition of periodic thermal shock. The temperature variation law inside the roller shell is studied during the process of continuous roll casting, and the steady temperature distributions of the roller shell at different casting velocities have been obtained when the thermal contact conductance between the roller shell and the casting strip is considered.

  3. Regulation of apoptotic signal transduction pathways by the heat shock proteins

    Institute of Scientific and Technical Information of China (English)

    LI; Zhengyu; ZHAO; Xia; WEI; Yuquan

    2004-01-01

    The study about apoptotic signal transductions has become a project to reveal the molecular mechanisms of apoptosis. Heat shock proteins (hsps), which play an important role in cell growth and apoptosis, have attracted great attentions. A lot of researches have showed there is a hsps superfamily including hsp90, hsp70, hsp60 and hsp27, etc., which regulates the biological behaviors of cells, particularly apoptotic signal transduction in Fas pathway, JNK/SAPK pathway and caspases pathway at different levels, partly by the function of molecular chaperone.

  4. Immunological enhancement action of endotoxin-free tilapia heat shock protein 70 against Streptococcus iniae.

    Science.gov (United States)

    Chen, Ming; Wang, Rui; Li, Liping; Liang, Wanwen; Wang, Qiuhua; Huang, Ting; Li, Chao; Li, Jian; Gan, Xi; Lei, Aiying; Huang, Weiyi; Luo, Honglin

    2014-07-01

    The immunological effects of heat shock proteins (HSPs) had been found in humans and mice, but scarce data of endotoxin-free Hsp70 were reported in tilapia. In the current study, we reported that tHsp70 alone and antigen-tHsp70 compound increased the proliferations of lymphocytes and macrophages, significantly increased the NO release and phagocytotic ability of macrophages (ptilapia lymphocytes and macrophages post S. iniae exposure and its up-regulation effects on vaccine-induced protection. Our research highlights the immunological enhancement action of Hsp70 in teleost immunity.

  5. Chronic SIV and Morphine treatment increases heat shock protein 5 expression at the synapse

    Science.gov (United States)

    Pendyala, Gurudutt; Periyasamy, Palsamy; Callen, Shannon; Fox, Howard S.; Lisco, Steven J.; Buch, Shilpa J.

    2015-01-01

    The abuse of opiates such as morphine in synergy with HIV infection accelerates neurocognitive impairments and neuropathology in the CNS of HIV infected subjects, collectively referred to as HAND. To identify potential pathogenic markers associated with HIV and morphine in perturbing the synaptic architecture, we performed quantitative mass spectrometry proteomics on purified synaptosomes isolated from the caudate of two groups of rhesus macaques chronically infected with SIV differing by one regimen- morphine treatment. The up regulation of heat shock 70 kDa protein 5 in the SIV+morphine group points to increased cellular stress during SIV/Morphine interaction thus leading to CNS dysfunction. PMID:26037114

  6. Influence of heat shock-treated cells on the production of glycerol and other metabolites in alcoholic fermentation

    Directory of Open Access Journals (Sweden)

    Sofoklis Petropoulos

    2010-11-01

    Full Text Available Sofoklis Petropoulos1,2, Paul R Grbin2, Vladimir Jiranek21SEMELI SA, Stamata Attica, Greece; 1,2School of Agriculture, Food and Wine, The University of Adelaide, South Australia, AustraliaAbstract: The impact of heat shock on the formation of sensorily important fermentation metabolites was investigated. Initially the heat tolerance of six commercial Saccharomyces cerevisiae yeast strains was evaluated under various conditions of time and temperature (heat shock at 40°C, 50°C, and 60°C for a duration of 20, 40, and 60 minutes, respectively. A chemically defined grape juice medium was inoculated from the surviving colonies, and microferments were conducted. Two strains were selected for further evaluation due to their heat shock tolerance and enhanced glycerol production. The experiment was repeated in standard laboratory scale fermentations under aerobic and anaerobic conditions, and the medium was inoculated directly after the heat shock treatment and after recovery from the heat shock on yeast peptone dextrose plates. All fermentations were further analyzed for higher alcohol, organic acid, and ethyl ester content using gas chromatography mass spectrometry. Elevated glycerol production (increase of 17% under aerobic conditions and 8% under anaerobic conditions was reported only in one strain and only after direct inoculation of the fermentation medium. With both strains, direct inoculation of the heated cells caused a 2-day delay in the commencement of the fermentation, but after recovery, the fermentation progress was increased. Volatile analysis showed that apart from changes in organic acids, all other volatile compounds analyzed exhibited an alteration mainly due to strain differences and the presence of oxygen.Keywords: heat shock, glycerol, higher alcohols, wine, Saccharomyces

  7. Heat shock protein in skeletal muscle cells%骨骼肌细胞与热休克蛋白

    Institute of Scientific and Technical Information of China (English)

    张晓峰; 王青涛; 李风晴

    2011-01-01

    BACKGROUND: There are many kinds of heat shock proteins in skeletal muscle, and they have important physiologic functions.OBJECTIVE: To review the features of heat shock proteins, and to discuss the significance of heat shock proteins under both physiological and physiologic conditions.METHODS: Databases of PubMed and CNKI were searched by computer using key words of "heat shock proteins, skeletal muscles, exercise, ischemia-reperfusion" both in English and Chinese. Literatures addressing heat shock proteins in skeletal muscles cells were included, and the repetitive researches were excluded.RESULTS AND CONCLUSION: A total of 197 documents were retrieved, and 35 articles were retained after depleting unrelated and repetitive ones. To date, skeletal muscles contain a variety of heat shock proteins, mainly comprise small heat shock protein,heat shock protein 70, heat shock protein 60 and heat shock protein 90. Heat shock proteins play an important role in reflecting intra-cellular changes during sports and monitoring over training. In addition, heat shock proteins are important in maintaining muscle function after over training or muscle injury.%背景:骨骼肌含有多种热休克蛋白,可能具有重要的生理功能.目的:综述骨骼肌热休克蛋白的特性,以及骨骼肌热休克蛋白在生理及病理情况下表达的意义.方法:以"热休克蛋白,骨骼肌,运动,缺血再灌注"为中文检索词,以"heat shock proteins,skeletal muscle,exercise,ischemia-reperfusion"为英文检索词,应用计算机检索Pubmed数据库和中文期刊全文数据库2010-06前发表的相关文章.纳入与骨骼肌细胞热休克蛋白研究相关的文献,排除重复性研究.结果与结论:共检索到197篇文献,排除无关重复的文献,保留35篇文献进行综述.目前研究证实骨骼肌含有多种热休克蛋白,主要有小热休克蛋白,热休克蛋白70,热休克蛋白60和热休克蛋白90等.热休克蛋白作为应激的指标,可以反

  8. Heating heavy ions in the polar corona by collisionless shocks: A one-dimensional simulation

    Science.gov (United States)

    Nisticò, Giuseppe; Zimbardo, Gaetano

    2012-01-01

    Recently a new model for explaining the observations of preferential heating of heavy ions in the polar solar corona was proposed (Zimbardo, 2010, 2011). In that model the ion energization mechanism is the ion reflection off supercritical quasi-perpendicular collisionless shocks in the corona and the subsequent acceleration by the motional electric field E = -V × B/c. The mechanism of heavy ion reflection is based on ion gyration in the magnetic overshoot of the shock. The acceleration due to the motional electric field is perpendicular to the magnetic field, giving rise to large temperature anisotropy with T⊥ ≫ T∥, in agreement with SoHO observations. Such a model is tested here by means of a one dimensional test particle simulation where ions are launched toward electric and magnetic profiles representing the shock transition. We study the dynamics of O5+, as representative of coronal heavy ions for Alfvénic Mach numbers of 2-4, as appropriate to solar corona. It is found that O5+ ions are easily reflected and gain more than mass proportional energy with respect to protons.

  9. Effects of heat shocks on microbial community structure and microbial activity of a methanogenic enrichment degrading benzoate.

    Science.gov (United States)

    Mei, R; Narihiro, T; Nobu, M K; Liu, W-T

    2016-11-01

    In anaerobic digesters, temperature fluctuation could lead to process instability and failure. It is still not well understood how digester microbiota as a whole respond to heat shock, and what specific organisms are vulnerable to perturbation or responsible for process recovery after perturbation. To address these questions, a mesophilic benzoate-degrading methanogenic culture enriched from digester was subjected to different levels of heat shock. Three types of methane production profiles after perturbation were observed in comparison to the control: uninhibited, inhibited with later recovery, and inhibited without recovery. These responses were correlated with the microbial community compositions based on the analyses of 16S rRNA and 16S rRNA gene. Specifically, the primary benzoate-degrading syntroph was highly affected by heat shock, and its abundance and activity were both crucial to the restoration of benzoate degradation after heat shock. In contrast, methanogens were stable regardless whether methane production was inhibited. Populations related to 'Candidatus Cloacimonetes' and Firmicutes showed stimulated growth. These observations indicated distinct physiological traits and ecological niches associated with individual microbial groups. The results obtained after exposure to heat shock can be critical to more comprehensive characterization of digester ecology under perturbations.

  10. Role of charred wood, heat-shock and light in germination of postfire phrygana species from the eastern Mediterranean Basin

    Science.gov (United States)

    Keeley, Jon E.; Babr-Keeley, Melanie

    1999-01-01

    Seeds of 22 species collected from recently burned phrygana were tested for their response to fire-type cues of charred wood and heat-shock. All Cistus species were stimulated by brief heat-shock, as shown in previous studies; however, none responded to charred wood. Only one of the 22 species was stimulated by charred wood, and only in dark-inhibited seeds, and this response did not occur in the light. The lack of charred-wood-induced germination is in contrast to the substantial proportion of species with this germination response reported for mediterranean-type vegetation in California, the Cape region of South Africa, and Western Australia. Phrygana has many species with heat-shock-stimulated germination, primarily in the Fabaceae and Cistaceae. This germination cue is widespread in these two families, thus, the presence of heat-shock-stimulated germination is a result of homologous, rather than covergent, adaptations in mediterranean-climate ecosystems. Germination response to light was not randomly distributed with respect to fire-type response. Heat-shock-stimulated species were almost uniformly light neutral, in contrast to more opportunistic colonizing species with non-refractory seeds, in which half of the species responded positively or negatively to light.

  11. The Role of Heat Shock Response in Insulin Resistance and Diabetes

    Directory of Open Access Journals (Sweden)

    Tatsuya Kondo

    2014-04-01

    Full Text Available The expansion of life-style related diseases, such as metabolic syndrome (MS and type 2 diabetes mellitus (T2DM, appears to be unstoppable. It is also difficult to cease their complications in spite of many antidiabetic medications or intervention of public administration. We and our collaborators found that physical medicine using simultaneous stimulation of heat with mild electric current activates heat shock response, thereby reducing visceral adiposity, insulin resistance, chronic inflammation and improving glucose homeostasis in mice models of T2DM, as well as in humans with MS or T2DM. This combination therapy exerts novel action on insulin signaling, β-cell protection and body compositions, and may provide a new therapeutic alternative in diabetic treatment strategy.

  12. The heat shock protein/chaperone network and multiple stress resistance

    KAUST Repository

    Jacob, Pierre

    2016-11-15

    Crop yield has been greatly enhanced during the last century. However, most elite cultivars are adapted to temperate climates and are not well suited to more stressful conditions. In the context of climate change, stress resistance is a major concern. To overcome these difficulties, scientists may help breeders by providing genetic markers associated with stress resistance. However, multi-stress resistance cannot be obtained from the simple addition of single stress resistance traits. In the field, stresses are unpredictable and several may occur at once. Consequently, the use of single stress resistance traits is often inadequate. Although it has been historically linked with the heat stress response, the heat shock protein (HSP)/chaperone network is a major component of multiple stress responses. Among the HSP/chaperone

  13. The role of heat shock response in insulin resistance and diabetes.

    Science.gov (United States)

    Kondo, Tatsuya; Motoshima, Hiroyuki; Igata, Motoyuki; Kawashima, Junji; Matsumura, Takeshi; Kai, Hirofumi; Araki, Eiichi

    2014-04-01

    The expansion of life-style related diseases, such as metabolic syndrome (MS) and type 2 diabetes mellitus (T2DM), appears to be unstoppable. It is also difficult to cease their complications in spite of many antidiabetic medications or intervention of public administration. We and our collaborators found that physical medicine using simultaneous stimulation of heat with mild electric current activates heat shock response, thereby reducing visceral adiposity, insulin resistance, chronic inflammation and improving glucose homeostasis in mice models of T2DM, as well as in humans with MS or T2DM. This combination therapy exerts novel action on insulin signaling, β-cell protection and body compositions, and may provide a new therapeutic alternative in diabetic treatment strategy.

  14. Exploring Mbar shock conditions and isochorically heated aluminum at the MEC end station of the LCLS

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, L. B.; Lee, H. J.; SLAC, aff; Barbrel, B.; Gauthier, M.; Galtier, E.; Nagler, B.; Doppner, T.; LePape, S.; Ma, T.; Pak, A.; Turnbull, D.; White, T.; Gregori, G.; Wei, M.; Falcone, R. W.; Heimann, P.; Zastrau, U.; Hastings, J. B.; Glenzer, S. H.

    2015-02-05

    Recent experiments performed at the Matter in Extreme Conditions end station (MEC) of the Linac Coherent Light Source (LCLS) have demonstrated the first spectrally resolved measurements of plasmons from isochorically heated aluminum. The experiments have been performed using a seeded 8-keV x-ray laser beam as a pump and probe to both volumetrically heat and scatter x-rays from aluminum. Collective x-ray Thomson scattering spectra show a well-resolved plasmon feature that is down-shifted in energy by 19 eV. In addition, Mbar shock pressures from laser-compressed aluminum foils using Velocity Interferometer System for Any Reflector (VISAR) have been measured. The combination of experiments fully demonstrates the possibility to perform warm dense matter studies at the LCLS with unprecedented accuracy and precision.

  15. Developmentally and stress-induced small heat shock proteins in cork oak somatic embryos.

    Science.gov (United States)

    Puigderrajols, Pere; Jofré, Anna; Mir, Gisela; Pla, Maria; Verdaguer, Dolors; Huguet, Gemma; Molinas, Marisa

    2002-06-01

    The timing and tissue localization of small heat shock proteins (sHSPs) during cork oak somatic embryo development was investigated under normal growing culture conditions and in response to stress. Western blot analyses using polyclonal antibodies raised against cork oak recombinant HSP17 showed a transient accumulation of class I sHSPs during somatic embryo maturation and germination. Moreover, the amount of protein increased at all stages of embryo development in response to exogenous stress. The developmentally accumulated proteins localized to early differentiating, but not the highly dividing, regions of the root and shoot apical meristems. By contrast, these highly dividing regions were strongly immunostained after heat stress. Findings support the hypothesis of a distinct control for developmentally and stress-induced accumulation of class I sHSPs. The possible role of sHSPs is discussed in relation to their tissue specific localization.

  16. PERAN HEAT SHOCK PROTEINS (HSP DALAM PATOGENESIS PENYAKIT OTOIMUN DI DALAM RONGGA MULUT

    Directory of Open Access Journals (Sweden)

    Endang W. Bachtiar

    2015-08-01

    Full Text Available Heat Shock Proteins (HSP are highly conserved immunoreactive group of proteins found in microorganisms and animal/human tissue. In addition to heat, other stressful conditiions also induce stressed proteins, especially anorexia, heavy metal ion, exposure to H2O2 and infection by DNA or RNA viruses. Recent studies suggest the involvement of HSPs as autoantigens in autoimmune diseases, including rheumatoid arthritis, systemic lupus erythematosus, Bechet's syndrome, recurrent oral uclers, oral lichen planus and other. The HSPs 60 - 65 KDa might be involved in the pathogenesis of autoimmune diseases such as Bechet's syndrome, recurrent oral ulcers, and oral lichen planus. This paper will discuss the immunopathogenesis mechanism of those diseases induced by HSPs.

  17. Shock initiation of the TATB-based explosive PBX-9502 heated to ˜ 76°C

    Science.gov (United States)

    Gustavsen, R. L.; Gehr, R. J.; Bucholtz, S. M.; Pacheco, A. H.; Bartram, B. D.

    2017-01-01

    We present gas-gun driven plate impact shock initiation experiments on the explosive PBX 9502 (95 weight percent triaminotrinitrobenzene, 5 weight percent Kel-F 800 binder) heated to ˜ 76°C. PBX 9502 samples were heated by flowing hot air through a sample mounting plate and surrounding coil. Temperatures were monitored using embedded and surface mounted type-E thermocouples. The shock to detonation transition was recorded using embedded electromagnetic particle velocity gauges. Results show increased shock sensitivity; time and distance to detonation onset vs. initial shock pressure are shorter than when the sample is initially at ambient temperature. Our results are consistent with those reported by Dallman and Wackerle: the "Pop-plot," or distance to detonation, xD, vs. impact pressure, P, is log10(xD) = 3.41 - 2.47 log10(P).

  18. Molecular chaperone activity of tomato (Lycopersicon esculentum) endoplasmic reticulum-located small heat shock protein.

    Science.gov (United States)

    Mamedov, Tarlan G; Shono, Mariko

    2008-03-01

    The gene encoding the small heat shock protein (sHSP), LeHSP21.5, has been previously cloned from tomato (GenBank accession no. AB026983). The deduced amino acid sequence of this tomato sHSP was most similar to that of other endoplasmic reticulum (ER)-localized sHSPs (ER-sHSP) and can be predicted to target the ER. We examined whether the gene product of LeHSP21.5 (probable ER-sHSP) can act as molecular chaperone. For functional analysis, LeHSP21.5 protein was expressed in Escherichia coli as His(6)-tagged protein in the C-terminal and purified. We confirmed that ER-sHSP could provide thermal protection of soluble proteins in vitro. We compared the thermal stability of E. coli strain BL21 (DE3) transformed with pET-ER-sHSP with the control E. coli strain BL21(DE3) transformed with only the pET vector under heat shock and IPTG-induced conditions. Most of the protein extracts from E. coli cells expressing ER-sHSP were protected from heat-induced denaturation, whereas extracts from cells not expressing ER-sHSP were very heat-sensitive under these conditions. A similar protective effect was observed when purified ER-sHSP was added to an E. coli cell extract. ER-sHSP prevented the thermal aggregation and inactivation of citrate synthase. These collective findings indicate that ER-sHSP can function as a molecular chaperone in vitro.

  19. Effects of heat shock on resistance to parasitoids and on life history traits in an aphid/endosymbiont system.

    Directory of Open Access Journals (Sweden)

    Luis Cayetano

    Full Text Available Temperature variation is an important factor determining the outcomes of interspecific interactions, including those involving hosts and parasites. This can apply to variation in average temperature or to relatively short but intense bouts of extreme temperature. We investigated the effect of heat shock on the ability of aphids (Aphis fabae harbouring protective facultative endosymbionts (Hamiltonella defensa to resist parasitism by Hymenopteran parasitoids (Lysiphlebus fabarum. Furthermore, we investigated whether heat shocks can modify previously observed genotype-by-genotype (G x G interactions between different endosymbiont isolates and parasitoid genotypes. Lines of genetically identical aphids possessing different isolates of H. defensa were exposed to one of two heat shock regimes (35°C and 39°C or to a control temperature (20°C before exposure to three different asexual lines of the parasitoids. We observed strong G x G interactions on parasitism rates, reflecting the known genetic specificity of symbiont-conferred resistance, and we observed a significant G x G x E interaction induced by heat shocks. However, this three-way interaction was mainly driven by the more extreme heat shock (39°C, which had devastating effects on aphid lifespan and reproduction. Restricting the analysis to the more realistic heat shock of 35°C, the G x G x E interaction was weaker (albeit still significant, and it did not lead to any reversals of the aphid lines' susceptibility rankings to different parasitoids. Thus, under conditions feasibly encountered in the field, the relative fitness of different parasitoid genotypes on hosts protected by particular symbiont strains remains mostly uncomplicated by heat stress, which should simplify biological control programs dealing with this system.

  20. Effects of heat transfer coefficient treatments on thermal shock fracture prediction for LWR fuel claddings in water quenching

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Youho; Lee, Jeong Ik; Cheon, Hee [KAIST, Daejeon (Korea, Republic of)

    2015-05-15

    Accurate modeling of thermal shock induced stresses has become ever most important to emerging accident-tolerant ceramic cladding concepts, such as silicon carbide (SiC) and SiC coated zircaloy. Since fractures of ceramic (entirely ceramic or coated) occur by excessive tensile stresses with linear elasticity, modeling transient stress distribution in the material provides a direct indication of the structural integrity. Indeed, even for the current zircaloy cladding material, the oxide layer formed on the surface - where cracks starts to develop upon water quenching - essentially behaves as a brittle ceramic. Hence, enhanced understanding of thermal shock fracture of a brittle material would fundamentally contribute to safety of nuclear reactors for both the current fuel design and that of the coming future. Understanding thermal shock fracture of a brittle material requires heat transfer rate between the solid and the fluid for transient temperature fields of the solid, and structural response of the solid under the obtained transient temperature fields. In water quenching, a solid experiences dynamic time-varying heat transfer rates with phase changes of the fluid over a short quenching period. Yet, such a dynamic change of heat transfer rates during the water quenching transience has been overlooked in assessments of mechanisms, predictability, and uncertainties for thermal shock fracture. Rather, a time-constant heat transfer coefficient, named 'effective heat transfer coefficient' has become a conventional input to thermal shock fracture analysis. No single constant heat transfer could suffice to depict the actual stress evolution subject to dynamic heat transfer coefficient changes with fluid phase changes. Use of the surface temperature dependent heat transfer coefficient will remarkably increase predictability of thermal shock fracture of brittle materials and complete the picture of stress evolution in the quenched solid. The presented result

  1. Heat shock protein 70 of Naegleria fowleri is important factor for proliferation and in vitro cytotoxicity.

    Science.gov (United States)

    Song, Kyoung-Ju; Song, Kyung-Hui; Kim, Jong-Hyun; Sohn, Hae-Jin; Lee, Yang-Jin; Park, Chang-Eun; Shin, Ho-Joon

    2008-07-01

    To evaluate the role of heat shock 70 protein (HSP70) in free-living amoeba, a constitutive and inducible heat shock 70 gene of pathogenic Naegleria fowleri has previously been cloned, characterized, and named as Nf-cHSP70. The Nf-cHSP70 is localized in the cytoplasm, pseudopodia, and phagocytic food-cups. To investigate the role of Nf-cHSP70 in the pathogenicity of N. fowleri, the synthesis of N. fowleri HSP70 was first inhibited with benzylidene lactam compound (KNK437), and Nf-cHSP70 gene was knock-downed with antisense oligomers, which were designed with a start region-specific antisense oligonucleotides (24 oligomers) and modified with phosphorothioate. KNK437 inhibited the induction of N. fowleri HSP70 in a dose-dependent manner. In addition, 300 muM KNK437 reduced the proliferation of N. fowleri to 79.4% of untreated control (100%). Nf-cHSP70 knock-downed N. fowleri with antisense oligomers showed 68.5% reduction of proliferation in comparison with untreated control (100%). The cytotoxicity of N. fowleri against CHO target cells was reduced to 42.1% by KNK437 and 68.6% by antisense oligomers. These results suggest that the cloned Nf-cHSP70 plays an important role in the proliferation and cytotoxicity of pathogenic N. fowleri.

  2. Time resolved spectra in the infrared absorption and emission from shock heated hydrocarbons. [in interstellar medium

    Science.gov (United States)

    Bauer, S. H.; Borchardt, D. B.

    1990-01-01

    The wavelength range of a previously constructed multichannel fast recording spectrometer was extended to the mid-infrared. With the initial configuration, light intensities were recorded simultaneously with a silicon-diode array simultaneously at 20 adjacent wavelengths, each with a 20-micron time resolution. For studies in the infrared, the silicon diodes were replaced by a 20-element PbSe array of similar dimensions, cooled by a three-stage thermoelectric device. It is proposed that infrared emissions could be due to shock-heated low molecular-weight hydrocarbons. The full Swan band system appeared in time-integrated emission spectra from shock-heated C2H2; no soot was generated. At low resolution, the profiles on the high-frequency side of the black body maximum show no distinctive features. These could be fitted to Planck curves, with temperatures that declined with time from an initial high that was intermediate between T5 (no conversion) and T5(eq).

  3. Heat shock transcriptional factors in Malus domestica: identification, classification and expression analysis

    Directory of Open Access Journals (Sweden)

    Giorno Filomena

    2012-11-01

    Full Text Available Abstract Background Heat shock transcriptional factors (Hsfs play a crucial role in plant responses to biotic and abiotic stress conditions and in plant growth and development. Apple (Malus domestica Borkh is an economically important fruit tree whose genome has been fully sequenced. So far, no detailed characterization of the Hsf gene family is available for this crop plant. Results A genome-wide analysis was carried out in Malus domestica to identify heat shock transcriptional factor (Hsf genes, named MdHsfs. Twenty five MdHsfs were identified and classified in three main groups (class A, B and C according to the structural characteristics and to the phylogenetic comparison with Arabidopsis thaliana and Populus trichocarpa. Chromosomal duplications were analyzed and segmental duplications were shown to have occurred more frequently in the expansion of Hsf genes in the apple genome. Furthermore, MdHsfs transcripts were detected in several apple organs, and expression changes were observed by quantitative real-time PCR (qRT-PCR analysis in developing flowers and fruits as well as in leaves, harvested from trees grown in the field and exposed to the naturally increased temperatures. Conclusions The apple genome comprises 25 full length Hsf genes. The data obtained from this investigation contribute to a better understanding of the complexity of the Hsf gene family in apple, and provide the basis for further studies to dissect Hsf function during development as well as in response to environmental stimuli.

  4. Salvianolate increases heat shock protein expression in a cerebral ischemia-reperfusion injury model

    Institute of Scientific and Technical Information of China (English)

    Jinnan Zhang; Wei Lu; Qiang Lei; Xi Tao; Hong You; Pinghui Xie

    2013-01-01

    Stroke remains a worldwide health problem. Salvianolate exerts a protective effect in various mi-crocirculatory disturbance-related diseases, but studies of the mechanisms underlying its protective action have mainly focused on the myocardium, whereas little research has been carried out in brain tissue fol owing ischemia-reperfusion. We assessed the neuroprotective effects of salvianolate in a rat model of cerebral ischemia-reperfusion injury induced using the suture method. At onset and 24 and 48 hours after reperfusion, rats were intraperitoneal y injected with salvianolate (18 mg/kg) or saline. Neurological deficit scores at 72 hours showed that the neurological functions of rats that had received salvianolate were significantly better than those of the rats that had received saline. 2,3,5-Triphenyltetrazolium chloride was used to stain cerebral tissue to determine the extent of the infarct area. A significantly smal er infarct area and a significantly lower number of apoptotic cel s were observed after treatment with salvianolate compared with the saline treatment. Expression of heat shock protein 22 and phosphorylated protein kinase B in ischemic brain tissue was significantly greater in rats treated with salvianolate compared with rats treated with saline. Our findings suggest that salvianolate provides neuroprotective effects against cerebral ischemia-reperfusion injury by upregulating heat shock protein 22 and phosphorylated protein kinase B expression.

  5. Immunohistochemical evaluation of the heat shock response to nonablative fractional resurfacing

    Science.gov (United States)

    Hantash, Basil M.; Bedi, Vikramaditya P.; Struck, Steven K.; Chan, Kin F.

    2010-11-01

    Despite the emergence of nonablative fractional resurfacing (NFR) as a new therapeutic modality for skin photoaging, little is known about the molecular events that underlie the heat shock response to different treatment parameters. Human subjects are treated with a scanned 1550-nm fractional laser at pulse energies spanning 6 to 40 mJ and a 140-μm spot size. The heat shock response is assessed immunohistochemically immediately through 7 days posttreatment. At the immediately posttreatment time point, we observe subepidermal clefting in most sections. The basal epidermis and dermal zones of sparing are both found to express HSP47, but not HSP72. By day 1, expression of HSP72 is detected throughout the epidermis, while that of HSP47 remains restricted to the basal layer. Both proteins are detected surrounding the dermal portion of the microscopic treatment zone (MTZ). This pattern of expression persists through day 7 post-NFR, although neither protein is found within the MTZ. Immediately posttreatment, the mean collagen denaturation zone width is 50 μm at 6 mJ, increasing to 202 μm at 40 mJ. The zone of cell death exceeds the denaturation zone by 19 to 55% over this pulse energy range. The two zones converge by day 7 posttreatment.

  6. Heat shock transcription factor 1 promotes the proliferation, migration and invasion of osteosarcoma cells.

    Science.gov (United States)

    Zhou, Zhenhua; Li, Yan; Jia, Qi; Wang, Zhiwei; Wang, Xudong; Hu, Jingjing; Xiao, Jianru

    2017-08-01

    Osteosarcoma is the most commonly diagnosed primary malignancy of bone and its overall survival rate is still very low. The molecular mechanisms underlying the progression of osteosarcoma have not been clearly illuminated. Heat shock transcription factor 1 (HSF1) is a key regulator of the heat shock response and also plays important roles in many cancers, but its function in osteosarcoma remains unexplored. In this study, the proliferation of osteosarcoma cells was determined by Cell Counting Kit-8 assays and colony formation assays. Transwell assays were used to demonstrate the migration and invasion abilities of osteosarcoma cells. A tumour formation assay in a nude mouse model was performed to assess the effect of HSF1 on osteosarcoma cell growth in vivo. The protein levels of HSF1 were analysed with immunohistochemical staining in samples from osteosarcoma patients. We demonstrated that knockdown of HSF1 reduced the proliferation, migration and invasion of osteosarcoma cells, while overexpression of HSF1 promoted the proliferation, migration and invasion of osteosarcoma cells. Furthermore, HSF1 promoted the proliferation of osteosarcoma cells in vivo. In addition, high levels of HSF1 were associated with a poor prognosis in osteosarcoma. These data highlight an important role of HSF1 in proliferation, migration and invasion of osteosarcoma cells. Moreover, the expression of HSF1 was associated with prognosis in osteosarcoma. © 2017 John Wiley & Sons Ltd.

  7. Heat shock factor 1 inducers from the bark of Eucommia ulmoides as cytoprotective agents.

    Science.gov (United States)

    Nam, Joo-Won; Kim, Seo-Young; Yoon, Taesook; Lee, Yoo Jin; Kil, Yun-Seo; Lee, Yun-Sil; Seo, Eun-Kyoung

    2013-07-01

    The barks of Eucommia ulmoides (Eucommiae Cortex, Eucommiaceae) have been used as a traditional medicine in Korea, Japan, and China to treat hypertension, reinforce the muscles and bones, and recover the damaged liver and kidney functions. Among these traditional uses, to establish the recovery effects on the damaged organs on the basis of phytochemistry, the barks of E. ulmoides have been investigated to afford three known phenolic compounds, coniferaldehyde glucoside (1), bartsioside (2), and feretoside (3), which were found in the family Eucommiaceae for the first time. The compounds 1-3 were evaluated for their inducible activities on the heat shock factor 1 (HSF1), and heat shock proteins (HSPs) 27 and 70, along with four compounds, geniposide (4), geniposidic acid (5), pinoresinol diglucoside (6), and liriodendrin (7), which were previously reported from E. ulmoides. Compounds 1-7 increased expression of HSF1 by a factor of 1.214, 1.144, 1.153, 1.114, 1.159, 1.041, and 1.167 at 3 μM, respectively. Coniferaldehyde glucoside (1) showed the most effective increase of HSF1 and induced successive expressions of HSP27 and HSP70 in a dose-dependent manner without cellular cytotoxicity, suggesting a possible application as a HSP inducer to act as cytoprotective agent.

  8. Response of S. boulardii cells to {sup 60} Co irradiation and heat shock

    Energy Technology Data Exchange (ETDEWEB)

    Neves, M.J.; Andrade, A.S.R.; Santos, R.G. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil); Nicoli, J.R. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. Microbiologia

    1997-12-31

    Full text. Preparation of Saccharomyces boulardii, a non pathogenic yeast, has been widely used in Europe and other countries to prevent gastrointestinal disorders. However the mechanism of action of theses cells on the illness is unknown but the efficacy of S. boulardii depends on its viability. As trehalose is a well known viability protectant in yeast cells against several adverse conditions, we determined its level. We measured the level of trehalose in cells submitted to heat shock, gamma irradiation and simulation of gastric environmental, all these conditions are commonly found during the bio therapeutic production and in the patients oral treatment. Trehalose levels were higher in yeast cells surviving to gamma irradiation ({sup 60} Cobalt) than in control cells. S. boulardii cells growth in log phase and submitted to the heat shock (40 deg C). Accumulated more trehalose than S. cerevisiae and unlikely to these cells, the pool of trehalose accumulated in S. boulardii was mobilized very slowly (70% of the trehalose pool was present 5 hours after the return to the normal temperature 30 deg C). Our results suggested a rather different trehalose metabolism in S. boulardii when compared with S. cerevisiae and showed that one of the response to the stress of irradiation was an increasing on the level of intracellular trehalose

  9. Oligomers of Heat-Shock Proteins: Structures That Don't Imply Function.

    Directory of Open Access Journals (Sweden)

    William M Jacobs

    2016-02-01

    Full Text Available Most proteins must remain soluble in the cytosol in order to perform their biological functions. To protect against undesired protein aggregation, living cells maintain a population of molecular chaperones that ensure the solubility of the proteome. Here we report simulations of a lattice model of interacting proteins to understand how low concentrations of passive molecular chaperones, such as small heat-shock proteins, suppress thermodynamic instabilities in protein solutions. Given fixed concentrations of chaperones and client proteins, the solubility of the proteome can be increased by tuning the chaperone-client binding strength. Surprisingly, we find that the binding strength that optimizes solubility while preventing irreversible chaperone binding also promotes the formation of weakly bound chaperone oligomers, although the presence of these oligomers does not significantly affect the thermodynamic stability of the solution. Such oligomers are commonly observed in experiments on small heat-shock proteins, but their connection to the biological function of these chaperones has remained unclear. Our simulations suggest that this clustering may not have any essential biological function, but rather emerges as a natural side-effect of optimizing the thermodynamic stability of the proteome.

  10. Emerging Role of Nitric Oxide and Heat Shock Proteins in Insulin Resistance.

    Science.gov (United States)

    Molina, Marisa Nile; Ferder, León; Manucha, Walter

    2016-01-01

    Insulin resistance (IR) is present in pathologies such as diabetes, obesity, metabolic syndrome, impaired glucose tolerance, hypertension, inflammation, cardiac disease, and dyslipidemias. Population studies show that IR is multifactorial and has genetic components, such as defects in the insulin-signaling pathway (as serine phosphorylation on insulin substrate or decreased activation of signaling molecules) and RAS/MAPK-dependent pathways. IR is connected to mitochondrial dysfunction, overproduction of oxidants, accumulation of fat, and an over-activation of the renin-angiotensin system linked to the NADPH oxidase activity. In addition, nitric oxide (NO), synthesized by nitric oxide synthases (endothelial and inducible), is also associated with IR when both impaired release and reduced bioavailability of all which lead to inflammation and hypertension. However, increased NO may promote vasculoprotection. Moreover, reduced NO release induces heat shock protein 70 kDa (HSP70) expression in IR and diabetes, mediating beneficial effects against oxidative stress injury, inflammation and apoptosis. HSP70 may be used as biomarker of the chronicity of diabetes. Hsp72 (inducible protein) is linked to vascular complications with a high-fat diet by blocking inflammation signaling (cytoprotective and anti-cytotoxicity intracellular role). Elucidating the IR signaling pathways and the roles of NO and HSPs is relevant to the application of new treatments, such as heat shock and thermal therapy, nitrosylated drugs, chemical chaperones or exercise training.

  11. Heat shock induces mini-Cajal bodies in the Xenopus germinal vesicle.

    Science.gov (United States)

    Handwerger, Korie E; Wu, Zheng'an; Murphy, Christine; Gall, Joseph G

    2002-05-15

    Cajal bodies are evolutionarily conserved nuclear organelles that are believed to play a central role in assembly of RNA transcription and processing complexes. Although knowledge of Cajal body composition and behavior has greatly expanded in recent years, little is known about the molecules and mechanisms that lead to the formation of these organelles in the nucleus. The Xenopus oocyte nucleus or germinal vesicle is an excellent model system for the study of Cajal bodies, because it is easy to manipulate and it contains 50-100 Cajal bodies with diameters up to 10 microm. In this study we show that numerous mini-Cajal bodies (less than 2 microm in diameter) form in the germinal vesicle after oocytes recover from heat shock. The mechanism for heat shock induction of mini-Cajal bodies is independent of U7 snRNA and does not require transcription or import of newly translated proteins from the cytoplasm. We suggest that Cajal bodies originate by self-organization of preformed components, preferentially on the surface of B-snurposomes.

  12. Induction of a heat shock response (HSP 72) in rat embryos exposed to selected chemical teratogens.

    Science.gov (United States)

    Mirkes, P E; Doggett, B; Cornel, L

    1994-02-01

    A monoclonal antibody to the 72 kD heat shock protein (HSP 72), Western blot analysis and 2-D gel electrophoresis/autoradiography were used to determine whether selected chemical teratogens induced the synthesis and accumulation of HSP 72 in postimplantation rat embryos exposed in vitro. The chemical teratogens studied include N-Acetoxy-2-acetylaminofluorene (N-Ac-AAF), cadmium chloride (CAD), cyclophosphamide (CP), sodium arsenite (AS), and sodium salicylate (SAL). Exposures to test chemicals were selected that produced obvious embryotoxicity characterized by abnormal development and growth retardation. Of the five chemical teratogens studied, AS and SAL induced the synthesis and accumulation of HSP 72 in day 10 rat embryos. The kinetics of HSP 72 accumulation, however, differed between AS- and SAL-treated embryos. Maximal levels of HSP 72 were observed 24 hours after AS exposure and 10 hours after SAL exposure. N-Ac-AAF, CD, and CP induced obvious embryotoxicity; however, none of these chemical teratogens induced HSP 72 at any of the timepoints assayed. Although only a small sample of chemical teratogens was studied, our results suggest that the heat shock response, characterized by the synthesis and accumulation of HSP 72, is not a general biomarker for chemical teratogens.

  13. Heat shock protein defenses in the neocortex and allocortex of the telencephalon.

    Science.gov (United States)

    Posimo, Jessica M; Weilnau, Justin N; Gleixner, Amanda M; Broeren, Matthew T; Weiland, Nicole L; Brodsky, Jeffrey L; Wipf, Peter; Leak, Rehana K

    2015-05-01

    The telencephalic allocortex develops protein inclusions before the neocortex in many age-related proteinopathies. One major defense mechanism against proteinopathic stress is the heat shock protein (Hsp) network. We therefore contrasted Hsp defenses in stressed primary neocortical and allocortical cells. Neocortical neurons were more resistant to the proteasome inhibitor MG132 than neurons from 3 allocortical subregions: entorhinal cortex, piriform cortex, and hippocampus. However, allocortical neurons exhibited higher MG132-induced increases in Hsp70 and heat shock cognate 70 (Hsc70). MG132-treated allocortical neurons also exhibited greater levels of protein ubiquitination. Inhibition of Hsp70/Hsc70 activity synergistically exacerbated MG132 toxicity in allocortical neurons more than neocortical neurons, suggesting that the allocortex is more reliant on these Hsp defenses. In contrast, astrocytes harvested from the neocortex or allocortex did not differ in their response to Hsp70/Hsc70 inhibition. Consistent with the idea that chaperones are maximally engaged in allocortical neurons, an increase in Hsp70/Hsc70 activity was protective only in neocortical neurons. Finally, the levels of select Hsps were altered in the neocortex and allocortex in vivo with aging.

  14. Virus-Heat Shock Protein Interaction and a Novel Axis for Innate Antiviral Immunity

    Directory of Open Access Journals (Sweden)

    Michael Oglesbee

    2012-09-01

    Full Text Available Virus infections induce heat shock proteins that in turn enhance virus gene expression, a phenomenon that is particularly well characterized for the major inducible 70 kDa heat shock protein (hsp70. However, hsp70 is also readily induced by fever, a phylogenetically conserved response to microbial infections, and when released from cells, hsp70 can stimulate innate immune responses through toll like receptors 2 and 4 (TLR2 and 4. This review examines how the virus-hsp70 relationship can lead to host protective innate antiviral immunity, and the importance of hsp70 dependent stimulation of virus gene expression in this host response. Beginning with the well-characterized measles virus-hsp70 relationship and the mouse model of neuronal infection in brain, we examine data indicating that the innate immune response is not driven by intracellular sensors of pathogen associated molecular patterns, but rather by extracellular ligands signaling through TLR2 and 4. Specifically, we address the relationship between virus gene expression, extracellular release of hsp70 (as a damage associated molecular pattern, and hsp70-mediated induction of antigen presentation and type 1 interferons in uninfected macrophages as a novel axis of antiviral immunity. New data are discussed that examines the more broad relevance of this protective mechanism using vesicular stomatitis virus, and a review of the literature is presented that supports the probable relevance to both RNA and DNA viruses and for infections both within and outside of the central nervous system.

  15. Heat Shock Protein-Peptide and HSP-Based Immunotherapies for the Treatment of Cancer.

    Science.gov (United States)

    Shevtsov, Maxim; Multhoff, Gabriele

    2016-01-01

    Intracellular residing heat shock proteins (HSPs) with a molecular weight of approximately 70 and 90 kDa function as molecular chaperones that assist folding/unfolding and transport of proteins across membranes and prevent protein aggregation after environmental stress. In contrast to normal cells, tumor cells have higher cytosolic heat shock protein 70 and Hsp90 levels, which contribute to tumor cell propagation, metastasis, and protection against apoptosis. In addition to their intracellular chaperoning functions, extracellular localized and membrane-bound HSPs have been found to play key roles in eliciting antitumor immune responses by acting as carriers for tumor-derived immunogenic peptides, as adjuvants for antigen presentation, or as targets for the innate immune system. The interaction of HSP-peptide complexes or peptide-free HSPs with receptors on antigen-presenting cells promotes the maturation of dendritic cells, results in an upregulation of major histocompatibility complex class I and class II molecules, induces secretion of pro- and anti-inflammatory cytokines, chemokines, and immune modulatory nitric oxides, and thus integrates adaptive and innate immune phenomena. Herein, we aim to recapitulate the history and current status of HSP-based immunotherapies and vaccination strategies in the treatment of cancer.

  16. Heat shock transcription factor 1-deficiency attenuates overloading-associated hypertrophy of mouse soleus muscle.

    Science.gov (United States)

    Koya, Tomoyuki; Nishizawa, Sono; Ohno, Yoshitaka; Goto, Ayumi; Ikuta, Akihiro; Suzuki, Miho; Ohira, Tomotaka; Egawa, Tatsuro; Nakai, Akira; Sugiura, Takao; Ohira, Yoshinobu; Yoshioka, Toshitada; Beppu, Moroe; Goto, Katsumasa

    2013-01-01

    Hypertrophic stimuli, such as mechanical stress and overloading, induce stress response, which is mediated by heat shock transcription factor 1 (HSF1), and up-regulate heat shock proteins (HSPs) in mammalian skeletal muscles. Therefore, HSF1-associated stress response may play a key role in loading-associated skeletal muscle hypertrophy. The purpose of this study was to investigate the effects of HSF1-deficiency on skeletal muscle hypertrophy caused by overloading. Functional overloading on the left soleus was performed by cutting the distal tendons of gastrocnemius and plantaris muscles for 4 weeks. The right muscle served as the control. Soleus muscles from both hindlimbs were dissected 2 and 4 weeks after the operation. Hypertrophy of soleus muscle in HSF1-null mice was partially inhibited, compared with that in wild-type (C57BL/6J) mice. Absence of HSF1 partially attenuated the increase of muscle wet weight and fiber cross-sectional area of overloaded soleus muscle. Population of Pax7-positive muscle satellite cells in HSF1-null mice was significantly less than that in wild-type mice following 2 weeks of overloading (pmuscle hypertrophy might be attributed to the greater and prolonged enhancement of IL-6 expression. HSF1 and/or HSF1-mediated stress response may, in part, play a key role in loading-induced skeletal muscle hypertrophy.

  17. Expression of Heat Shock Protein 70 mRNA in Epithelial Cells of Human Lens

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Objective:To try to find out the pathogenesis of the cataract , effects of beat and oxidative stresson heat shock proteins of tissue cultured human lens epithelial cells (LEC-B3) were investigate& Methods:Cells were exposed to heat shock (45℃) and oxidative stress(5OmMH2O2 for 30 min, and then allowed to recoverat different intervals (Oh, 2h, 4h, 6h, 16h, 24h) in physiological medium Reverse transcription polymerasechain reaction (RT-PCR) were used to determined the level of HSP70. Results: HSPs existed in both physiologicaland stressful situation. The level of HSP7OmRNA increased 2h later after both stresses. The expression of HSP70got to the summit during 2h to 6h in each group. Subsequently it decreased gradually in each group, maintaininga high level at 16h. Conclusion: HSP70 exists in lens epithelial cells and can be induced after stress. Thedata suggested it may play an important protective role in lens epithelial cells in respond to cellular stress.

  18. New Evidence for Efficient Collisionless Heating of Electrons at the Reverse Shock of a Young Supernova Remnant

    CERN Document Server

    Yamaguchi, Hiroya; Badenes, Carles; Hughes, John P; Brickhouse, Nancy S; Foster, Adam R; Patnaude, Daniel J; Petre, Robert; Slane, Patrick O; Smith, Randall K

    2013-01-01

    Although collisionless shocks are ubiquitous in astrophysics, certain key aspects of them are not well understood. In particular, the process known as collisionless electron heating, whereby electrons are rapidly energized at the shock front, is one of the main open issues in shock physics. Here we present the first clear evidence for efficient collisionless electron heating at the reverse shock of Tycho's supernova remnant (SNR), revealed by Fe-K diagnostics using high-quality X-ray data obtained by the Suzaku satellite. We detect K-beta (3p->1s) fluorescence emission from low-ionization Fe ejecta excited by energetic thermal electrons at the reverse shock front, which peaks at a smaller radius than Fe K-alpha (2p->1s) emission dominated by a relatively highly-ionized component. Comparison with our hydrodynamical simulations implies instantaneous electron heating to a temperature 1000 times higher than expected from Coulomb collisions alone. The unique environment of the reverse shock, which is propagating w...

  19. Reduced heat shock response in human mononuclear cells during aging and its association with polymorphisms in HSP70 genes

    DEFF Research Database (Denmark)

    Singh, Ripudaman; Kølvraa, Steen; Bross, Peter

    2006-01-01

    Age-dependent changes in heat shock response (HSR) were studied in mononuclear cells (monocytes and lymphocytes) collected from young (mean age = 22.6 +/- 1.7 years) and middle-aged (mean age = 56.3 +/- 4.7 years) subjects after 1 hour of heat shock at 42 degrees C. Genotype-specific HSR...... was measured by genotyping the subjects for 3 single nucleotide polymorphisms, HSPA1A(A-110C), HSPA1B(A1267G), and HSPA1L(T2437C), 1 each in the 3 HSP70 genes. A significant age-related decrease in the induction of Hsp70 occurred after heat shock in both monocytes and lymphocytes. The noninducible...

  20. Heat shock proteins and survival strategies in congeneric land snails (Sphincterochila) from different habitats.

    Science.gov (United States)

    Mizrahi, Tal; Heller, Joseph; Goldenberg, Shoshana; Arad, Zeev

    2012-09-01

    Polmunate land snails are subject to stress conditions in their terrestrial habitat, and depend on a range of behavioural, physiological and biochemical adaptations for coping with problems of maintaining water, ionic and thermal balance. The involvement of the heat shock protein (HSP) machinery in land snails was demonstrated following short-term experimental aestivation and heat stress, suggesting that land snails use HSPs as part of their survival strategy. As climatic variation was found to be associated with HSP expression, we tested whether adaptation of land snails to different habitats affects HSP expression in two closely related Sphincterochila snail species, a desert species Sphincterochila zonata and a Mediterranean-type species Sphincterochila cariosa. Our study suggests that Sphincterochila species use HSPs as part of their survival strategy following desiccation and heat stress, and as part of the natural annual cycle of activity and aestivation. Our studies also indicate that adaptation to different habitats results in the development of distinct strategies of HSP expression in response to stress, namely the reduced expression of HSPs in the desert-inhabiting species. We suggest that these different strategies reflect the difference in heat and aridity encountered in the natural habitats, and that the desert species S. zonata relies on mechanisms and adaptations other than HSP induction thus avoiding the fitness consequences of continuous HSP upregulation.

  1. Heat shock response in yeast involves changes in both transcription rates and mRNA stabilities.

    Directory of Open Access Journals (Sweden)

    Laia Castells-Roca

    Full Text Available We have analyzed the heat stress response in the yeast Saccharomyces cerevisiae by determining mRNA levels and transcription rates for the whole transcriptome after a shift from 25 °C to 37 °C. Using an established mathematical algorithm, theoretical mRNA decay rates have also been calculated from the experimental data. We have verified the mathematical predictions for selected genes by determining their mRNA decay rates at different times during heat stress response using the regulatable tetO promoter. This study indicates that the yeast response to heat shock is not only due to changes in transcription rates, but also to changes in the mRNA stabilities. mRNA stability is affected in 62% of the yeast genes and it is particularly important in shaping the mRNA profile of the genes belonging to the environmental stress response. In most cases, changes in transcription rates and mRNA stabilities are homodirectional for both parameters, although some interesting cases of antagonist behavior are found. The statistical analysis of gene targets and sequence motifs within the clusters of genes with similar behaviors shows that both transcriptional and post-transcriptional regulons apparently contribute to the general heat stress response by means of transcriptional factors and RNA binding proteins.

  2. Effects of heat shock, stannous chloride, and gallium nitrate on the rat inflammatory response.

    Science.gov (United States)

    House, S D; Guidon, P T; Perdrizet, G A; Rewinski, M; Kyriakos, R; Bockman, R S; Mistry, T; Gallagher, R A; Hightower, L E

    2001-04-01

    Heat and a variety of other stressors cause mammalian cells and tissues to acquire cytoprotection. This transient state of altered cellular physiology is nonproliferative and antiapoptotic. In this study, male Wistar rats were stress conditioned with either stannous chloride or gallium nitrate, which have immunosuppressive effects in vivo and in vitro, or heat shock, the most intensively studied inducer of cytoprotection. The early stages of inflammation in response to topical suffusion of mesentery tissue with formyl-methionyl-leucyl-phenylalanine (FMLP) were monitored using intravital microscopy. Microvascular hemodynamics (venular diameter, red blood cell velocity [Vrbc], white blood cell [WBC] flux, and leukocyte-endothelial adhesion [LEA]) were used as indicators of inflammation, and tissue levels of inducible Hsp70, determined using immunoblot assays, provided a marker of cytoprotection. None of the experimental treatments blocked decreases in WBC flux during FMLP suffusion, an indicator of increased low-affinity interactions between leukocytes and vascular endothelium known as rolling adhesion. During FMLP suffusion LEA, an indicator of firm attachment between leukocytes and vascular endothelial cells increased in placebo and gallium nitrate-treated animals but not in heat- and stannous chloride-treated animals, an anti-inflammatory effect. Hsp70 was not detected in aortic tissue from placebo and gallium nitrate-treated animals, indicating that Hsp70-dependent cytoprotection was not present. In contrast, Hsp70 was detected in aortic tissues from heat- and stannous chloride-treated animals, indicating that these tissues were in a cytoprotected state that was also an anti-inflammatory state.

  3. Genome-wide identification, classification and analysis of heat shock transcription factor family in maize

    Directory of Open Access Journals (Sweden)

    Zhu Su-Wen

    2011-01-01

    Full Text Available Abstract Background Heat shock response in eukaryotes is transcriptionally regulated by conserved heat shock transcription factors (Hsfs. Hsf genes are represented by a large multigene family in plants and investigation of the Hsf gene family will serve to elucidate the mechanisms by which plants respond to stress. In recent years, reports of genome-wide structural and evolutionary analysis of the entire Hsf gene family have been generated in two model plant systems, Arabidopsis and rice. Maize, an important cereal crop, has represented a model plant for genetics and evolutionary research. Although some Hsf genes have been characterized in maize, analysis of the entire Hsf gene family were not completed following Maize (B73 Genome Sequencing Project. Results A genome-wide analysis was carried out in the present study to identify all Hsfs maize genes. Due to the availability of complete maize genome sequences, 25 nonredundant Hsf genes, named ZmHsfs were identified. Chromosomal location, protein domain and motif organization of ZmHsfs were analyzed in maize genome. The phylogenetic relationships, gene duplications and expression profiles of ZmHsf genes were also presented in this study. Twenty-five ZmHsfs were classified into three major classes (class A, B, and C according to their structural characteristics and phylogenetic comparisons, and class A was further subdivided into 10 subclasses. Moreover, phylogenetic analysis indicated that the orthologs from the three species (maize, Arabidopsis and rice were distributed in all three classes, it also revealed diverse Hsf gene family expression patterns in classes and subclasses. Chromosomal/segmental duplications played a key role in Hsf gene family expansion in maize by investigation of gene duplication events. Furthermore, the transcripts of 25 ZmHsf genes were detected in the leaves by heat shock using quantitative real-time PCR. The result demonstrated that ZmHsf genes exhibit different

  4. LPS-induced delayed preconditioning is mediated by Hsp90 and involves the heat shock response in mouse kidney.

    Directory of Open Access Journals (Sweden)

    Tamás Kaucsár

    Full Text Available We and others demonstrated previously that preconditioning with endotoxin (LPS protected from a subsequent lethal LPS challenge or from renal ischemia-reperfusion injury (IRI. LPS is effective in evoking the heat shock response, an ancient and essential cellular defense mechanism, which plays a role in resistance to, and recovery from diseases. Here, by using the pharmacological Hsp90 inhibitor novobiocin (NB, we investigated the role of Hsp90 and the heat shock response in LPS-induced delayed renal preconditioning.Male C57BL/6 mice were treated with preconditioning (P: 2 mg/kg, i.p. and subsequent lethal (L: 10 mg/kg, i.p. doses of LPS alone or in combination with NB (100 mg/kg, i.p.. Controls received saline (C or NB.Preconditioning LPS conferred protection from a subsequent lethal LPS treatment. Importantly, the protective effect of LPS preconditioning was completely abolished by a concomitant treatment with NB. LPS induced a marked heat shock protein increase as demonstrated by Western blots of Hsp70 and Hsp90. NB alone also stimulated Hsp70 and Hsp90 mRNA but not protein expression. However, Hsp70 and Hsp90 protein induction in LPS-treated mice was abolished by a concomitant NB treatment, demonstrating a NB-induced impairment of the heat shock response to LPS preconditioning.LPS-induced heat shock protein induction and tolerance to a subsequent lethal LPS treatment was prevented by the Hsp90 inhibitor, novobiocin. Our findings demonstrate a critical role of Hsp90 in LPS signaling, and a potential involvement of the heat shock response in LPS-induced preconditioning.

  5. Heat shock protein 70-dependent protective effect of polaprezinc on acetylsalicylic acid-induced apoptosis of rat intestinal epithelial cells.

    Science.gov (United States)

    Qin, Ying; Naito, Yuji; Handa, Osamu; Hayashi, Natsuko; Kuki, Aiko; Mizushima, Katsura; Omatsu, Tatsushi; Tanimura, Yuko; Morita, Mayuko; Adachi, Satoko; Fukui, Akifumi; Hirata, Ikuhiro; Kishimoto, Etsuko; Nishikawa, Taichiro; Uchiyama, Kazuhiko; Ishikawa, Takeshi; Takagi, Tomohisa; Yagi, Nobuaki; Kokura, Satoshi; Yoshikawa, Toshikazu

    2011-11-01

    Protection of the small intestine from mucosal injury induced by nonsteroidal anti-inflammatory drugs including acetylsalicylic acid is a critical issue in the field of gastroenterology. Polaprezinc an anti-ulcer drug, consisting of zinc and L-carnosine, provides gastric mucosal protection against various irritants. In this study, we investigated the protective effect of polaprezinc on acetylsalicylic acid-induced apoptosis of the RIE1 rat intestinal epithelial cell line. Confluent rat intestinal epithelial cells were incubated with 70 µM polaprezinc for 24 h, and then stimulated with or without 15 mM acetylsalicylic acid for a further 15 h. Subsequent cellular viability was quantified by fluorometric assay based on cell lysis and staining. Acetylsalicylic acid-induced cell death was also qualified by fluorescent microscopy of Hoechst33342 and propidium iodide. Heat shock proteins 70 protein expression after adding polaprezinc or acetylsalicylic acid was assessed by western blotting. To investigate the role of Heat shock protein 70, Heat shock protein 70-specific small interfering RNA was applied. Cell viability was quantified by fluorometric assay based on cell lysis and staining and apoptosis was analyzed by fluorescence-activated cell sorting. We found that acetylsalicylic acid significantly induced apoptosis of rat intestinal epithelial cells in a dose- and time-dependent manner. Polaprezinc significantly suppressed acetylsalicylic acid-induced apoptosis of rat intestinal epithelial cells at its late phase. At the same time, polaprezinc increased Heat shock protein 70 expressions of rat intestinal epithelial cells in a time-dependent manner. However, in Heat shock protein 70-silenced rat intestinal epithelial cells, polaprezinc could not suppress acetylsalicylic acid -induced apoptosis at its late phase. We conclude that polaprezinc-increased Heat shock protein 70 expression might be an important mechanism by which polaprezinc suppresses acetylsalicylic

  6. Identification of Heat Shock Transcription Factor Genes Involved in Thermotolerance of Octoploid Cultivated Strawberry

    Science.gov (United States)

    Liao, Wan-Yu; Lin, Lee-Fong; Jheng, Jing-Lian; Wang, Chun-Chung; Yang, Jui-Hung; Chou, Ming-Lun

    2016-01-01

    Heat shock transcription factors (HSFs) are mainly involved in the activation of genes in response to heat stress as well as other abiotic and biotic stresses. The growth, development, reproduction, and yield of strawberry are strongly limited by extreme temperatures and droughts. In this study, we used Illumina sequencing and obtained transcriptome data set from Fragaria × ananassa Duchessne cv. Toyonoka. Six contigs and three unigenes were confirmed to encode HSF proteins (FaTHSFs). Subsequently, we characterized the biological functions of two particularly selected unigenes, FaTHSFA2a and FaTHSFB1a, which were classified into class A2 and B HSFs, respectively. Expression assays revealed that FaTHSFA2a and FaTHSFB1a expression was induced by heat shock and correlated well with elevated ambient temperatures. Overexpression of FaTHSFA2a and FaTHSFB1a resulted in the activation of their downstream stress-associated genes, and notably enhanced the thermotolerance of transgenic Arabidopsis plants. Besides, both FaTHSFA2a and FaTHSFB1a fusion proteins localized in the nucleus, indicating their similar subcellular distributions as transcription factors. Our yeast one-hybrid assay suggested that FaTHSFA2a has trans-activation activity, whereas FaTHSFB1a expresses trans-repression function. Altogether, our annotated transcriptome sequences provide a beneficial resource for identifying most genes expressed in octoploid strawberry. Furthermore, HSF studies revealed the possible insights into the molecular mechanisms of thermotolerance, thus rendering valuable molecular breeding to improve the tolerance of strawberry in response to high-temperature stress. PMID:27999304

  7. The stress protein heat shock cognate 70 (Hsc70) inhibits the Transient Receptor Potential Vanilloid type 1 (TRPV1) channel

    Science.gov (United States)

    Iftinca, Mircea; Flynn, Robyn; Basso, Lilian; Melo, Helvira; Aboushousha, Reem; Taylor, Lauren

    2016-01-01

    Background Specialized cellular defense mechanisms prevent damage from chemical, biological, and physical hazards. The heat shock proteins have been recognized as key chaperones that maintain cell survival against a variety of exogenous and endogenous stress signals including noxious temperature. However, the role of heat shock proteins in nociception remains poorly understood. We carried out an expression analysis of the constitutively expressed 70 kDa heat-shock cognate protein, a member of the stress-induced HSP70 family in lumbar dorsal root ganglia from a mouse model of Complete Freund’s Adjuvant-induced chronic inflammatory pain. We used immunolabeling of dorsal root ganglion neurons, behavioral analysis and patch clamp electrophysiology in both dorsal root ganglion neurons and HEK cells transfected with Hsc70 and Transient Receptor Potential Channels to examine their functional interaction in heat shock stress condition. Results We report an increase in protein levels of Hsc70 in mouse dorsal root ganglia, 3 days post Complete Freund’s Adjuvant injection in the hind paw. Immunostaining of Hsc70 was observed in most of the dorsal root ganglion neurons, including the small size nociceptors immunoreactive to the TRPV1 channel. Standard whole-cell patch-clamp technique was used to record Transient Receptor Potential Vanilloid type 1 current after exposure to heat shock. We found that capsaicin-evoked currents are inhibited by heat shock in dorsal root ganglion neurons and transfected HEK cells expressing Hsc70 and TRPV1. Blocking Hsc70 with matrine or spergualin compounds prevented heat shock-induced inhibition of the channel. We also found that, in contrast to TRPV1, both the cold sensor channels TRPA1 and TRPM8 were unresponsive to heat shock stress. Finally, we show that inhibition of TRPV1 depends on the ATPase activity of Hsc70 and involves the rho-associated protein kinase. Conclusions Our work identified Hsc70 and its ATPase activity as a central

  8. Effect of Calcium Lactate and Heat-Shock on Texture in Fresh-Cut Lettuce During Storage

    OpenAIRE

    Martin-Diana, Ana Belen; Rico, Daniel; Frias, Jesus Maria; Henehan, Gary; Mulcahy, Jemina; Barat, J.; Barry-Ryan, Catherine

    2006-01-01

    Textural and microstructural changes in fresh-cut lettuce were analysed over 12 days storage. The vegetable was treated with 120 ppm chlorine and with 15 g/L calcium lactate at room temperature (18–20 °C) and at 50 °C (heat-shock). Texturometer analysis showed that samples washed with calcium lactate had significantly (p > 0.05) higher crispness values than samples washed with chlorine. However the use of 50 °C treatment (heat-shock) gave better textural properties at the end of storage and s...

  9. Heat shock factors in tomatoes: genome-wide identification, phylogenetic analysis and expression profiling under development and heat stress

    Directory of Open Access Journals (Sweden)

    Xuedong Yang

    2016-05-01

    Full Text Available The HSF (heat shock factor gene family contains highly conserved plant-specific transcription factors that play an important role in plant high-temperature stress responses. The present study aimed to characterize the HSF transcription factor genes in tomato (Solanum lycopersicum, which is an important vegetable crop worldwide and the model plant for fruit development studies. Twenty-six SlyHSF genes were identified in tomato, and the phylogenetic analysis showed the possible evolution profile of subgroups among in the plant kingdom. A new group O was identified that involved HSF genes in primitive plant species, like in the green algae, mosses and lycophytes. The gene structure and motifs of each SlyHSF were comprehensively analyzed. We identified orthologous, co-orthologous and paralogous HSF gene pairs in tomato, Arabidopsis and rice, and constructed a complex interaction network among these genes. The SlyHSF genes were expressed differentially in different species and at a higher level in mature fruits. The qPCR analysis was performed and showed SlyHSF genes greatly participate in plant heat tolerant pathways. Our comprehensive genome-wide analysis provided insights into the HSF gene family of tomatoes.

  10. Heterologous expression of a plant small heat-shock protein enhances Escherichia coli viability under heat and cold stress.

    Science.gov (United States)

    Soto, A; Allona, I; Collada, C; Guevara, M A; Casado, R; Rodriguez-Cerezo, E; Aragoncillo, C; Gomez, L

    1999-06-01

    A small heat-shock protein (sHSP) that shows molecular chaperone activity in vitro was recently purified from mature chestnut (Castanea sativa) cotyledons. This protein, renamed here as CsHSP17. 5, belongs to cytosolic class I, as revealed by cDNA sequencing and immunoelectron microscopy. Recombinant CsHSP17.5 was overexpressed in Escherichia coli to study its possible function under stress conditions. Upon transfer from 37 degrees C to 50 degrees C, a temperature known to cause cell autolysis, those cells that accumulated CsHSP17.5 showed improved viability compared with control cultures. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of cell lysates suggested that such a protective effect in vivo is due to the ability of recombinant sHSP to maintain soluble cytosolic proteins in their native conformation, with little substrate specificity. To test the recent hypothesis that sHSPs may be involved in protection against cold stress, we also studied the viability of recombinant cells at 4 degrees C. Unlike the major heat-induced chaperone, GroEL/ES, the chestnut sHSP significantly enhanced cell survivability at this temperature. CsHSP17.5 thus represents an example of a HSP capable of protecting cells against both thermal extremes. Consistent with these findings, high-level induction of homologous transcripts was observed in vegetative tissues of chestnut plantlets exposed to either type of thermal stress but not salt stress.

  11. Non-lethal heat shock increased Hsp70 and immune protein transcripts but not Vibrio tolerance in the white-leg shrimp.

    Directory of Open Access Journals (Sweden)

    Nguyen Hong Loc

    Full Text Available Non-lethal heat shock boosts bacterial and viral disease tolerance in shrimp, possibly due to increases in endogenous heat shock protein 70 (Hsp70 and/or immune proteins. To further understand the mechanisms protecting shrimp against infection, Hsp70 and the mRNAs encoding the immune-related proteins prophenoloxidase (proPO, peroxinectin, penaeidin, crustin and hemocyanin were studied in post-larvae of the white-leg shrimp Litopenaeus vannamei, following a non-lethal heat shock. As indicated by RT-qPCR, a 30 min abrupt heat shock increased Hsp70 mRNA in comparison to non-heated animals. Immunoprobing of western blots and quantification by ELISA revealed that Hsp70 production after heat shock was correlated with enhanced Hsp70 mRNA. proPO and hemocyanin mRNA levels were augmented, whereas peroxinectin and crustin mRNA levels were unchanged following non-lethal heat shock. Penaeidin mRNA was decreased by all heat shock treatments. Thirty min abrupt heat shock failed to improve survival of post-larvae in a standardized challenge test with Vibrio harveyi, indicating that under the conditions of this study, L. vannamei tolerance to Vibrio infection was influenced neither by Hsp70 accumulation nor the changes in the immune-related proteins, observations dissimilar to other shrimp species examined.

  12. Magnetogasdynamic spherical shock wave in a non-ideal gas under gravitational field with conductive and radiative heat fluxes

    Science.gov (United States)

    Nath, G.; Vishwakarma, J. P.

    2016-11-01

    Similarity solutions are obtained for the flow behind a spherical shock wave in a non-ideal gas under gravitational field with conductive and radiative heat fluxes, in the presence of a spatially decreasing azimuthal magnetic field. The shock wave is driven by a piston moving with time according to power law. The radiation is considered to be of the diffusion type for an optically thick grey gas model and the heat conduction is expressed in terms of Fourier's law for heat conduction. Similarity solutions exist only when the surrounding medium is of constant density. The gas is assumed to have infinite electrical conductivity and to obey a simplified van der Waals equation of state. It is shown that an increase of the gravitational parameter or the Alfven-Mach number or the parameter of the non-idealness of the gas decreases the compressibility of the gas in the flow-field behind the shock, and hence there is a decrease in the shock strength. The pressure and density vanish at the inner surface (piston) and hence a vacuum is formed at the center of symmetry. The shock waves in conducting non-ideal gas under gravitational field with conductive and radiative heat fluxes can be important for description of shocks in supernova explosions, in the study of a flare produced shock in the solar wind, central part of star burst galaxies, nuclear explosion etc. The solutions obtained can be used to interpret measurements carried out by space craft in the solar wind and in neighborhood of the Earth's magnetosphere.

  13. Expression of Heat Shock Protein Genes in Different Developmental Stages and After Temperature Stress in the Maize Weevil (Coleoptera: Curculionidae).

    Science.gov (United States)

    Tungjitwitayakul, Jatuporn; Tatun, Nujira; Vajarasathira, Boongeua; Sakurai, Sho

    2015-06-01

    The maize weevil, Sitophilus zeamais Motschulsky, is a major pest of rice and other postharvest grain stocks in tropical countries. Heating and cooling treatments have been adopted to control this pest. Because heat shock protein (hsp) genes respond to temperature stress, we examined the association of hsp genes with development and thermal stress in S. zeamais. The temperature response of the insect to heat and cold treatments was assessed at four developmental stages: egg, larva, pupa, and adult. LT50 values at high temperatures were similar among the four developmental stages, while adults were the most tolerant to low temperatures, and eggs, larvae, and pupae exhibited similar LT50 values. Expression levels of three hsps--Szhsp70, Szhsc70, and Szhsp90--fluctuated substantially throughout the four stages at a rearing temperature of 28°C. Heat shock and cold shock increased the expression of all three hsps, and the highest upregulation was observed at 40°C, although the intensity of upregulation varied among the three genes: strongly in Szhsp70, moderately in Szhsp90, and slightly in Szhsc70. Basal expression of the three hsps at 28°C and gene responses to heat and cold shock also varied significantly at the tissue level.

  14. Shock-induced heating and millisecond boiling in gels and tissue due to high intensity focused ultrasound.

    Science.gov (United States)

    Canney, Michael S; Khokhlova, Vera A; Bessonova, Olga V; Bailey, Michael R; Crum, Lawrence A

    2010-02-01

    Nonlinear propagation causes high-intensity ultrasound waves to distort and generate higher harmonics, which are more readily absorbed and converted to heat than the fundamental frequency. Although such nonlinear effects have been investigated previously and found to not significantly alter high-intensity focused ultrasound (HIFU) treatments, two results reported here change this paradigm. One is that at clinically relevant intensity levels, HIFU waves not only become distorted but form shock waves in tissue. The other is that the generated shock waves heat the tissue to boiling in much less time than predicted for undistorted or weakly distorted waves. In this study, a 2-MHz HIFU source operating at peak intensities up to 25,000 W/cm(2) was used to heat transparent tissue-mimicking phantoms and ex vivo bovine liver samples. Initiation of boiling was detected using high-speed photography, a 20-MHz passive cavitation detector and fluctuation of the drive voltage at the HIFU source. The time to boil obtained experimentally was used to quantify heating rates and was compared with calculations using weak shock theory and the shock amplitudes obtained from nonlinear modeling and measurements with a fiber optic hydrophone. As observed experimentally and predicted by calculations, shocked focal waveforms produced boiling in as little as 3 ms and the time to initiate boiling was sensitive to small changes in HIFU output. Nonlinear heating as a result of shock waves is therefore important to HIFU, and clinicians should be aware of the potential for very rapid boiling because it alters treatments.

  15. Inducing Muscle Heat Shock Protein 70 Improves Insulin Sensitivity and Muscular Performance in Aged Mice.

    Science.gov (United States)

    Silverstein, Marnie G; Ordanes, Diane; Wylie, Ashley T; Files, D Clark; Milligan, Carol; Presley, Tennille D; Kavanagh, Kylie

    2015-07-01

    Heat shock proteins (HSPs) are molecular chaperones with roles in longevity and muscular preservation. We aimed to show elevating HSP70 improves indices of health span. Aged C57/BL6 mice acclimated to a western diet were randomized into: geranylgeranylacetone (GGA)-treated (100 mg/kg/d), biweekly heat therapy (HT), or control. The GGA and HT are well-known pharmacological and environmental inducers of HSP70, respectively. Assessments before and after 8 weeks of treatment included glycemic endpoints, body composition, and muscular endurance, power, and perfusion. An HT mice had more than threefold, and GGA mice had a twofold greater HSP70 compared with control. Despite comparable body compositions, both treatment groups had significantly better insulin sensitivity and insulin signaling capacity. Compared with baseline, HT mice ran 23% longer than at study start, which was significantly more than GGA or control. Hanging ability (muscular endurance) also tended to be best preserved in HT mice. Muscle power, contractile force, capillary perfusion, and innervation were not different. Heat treatment has a clear benefit on muscular endurance, whereas HT and GGA both improved insulin sensitivity. Different effects may relate to muscle HSP70 levels. An HSP induction could be a promising approach for improving health span in the aged mice. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Characterization of heat-shock proteins in Escherichia coli strains under thermal stress in vitro.

    Science.gov (United States)

    Urban-Chmiel, Renata; Dec, Marta; Puchalski, Andrzej; Wernicki, Andrzej

    2013-12-01

    The aim of this study was to evaluate the effect of heat stress in in vitro conditions on the induction of heat-shock protein (Hsp)70 by Escherichia coli cells, and to determine the localization of Hsps in cell fractions. The material consisted of wild strains of E. coli isolated from the digestive tract of calves, suspended in an exponential-phase culture and subjected to 41.5 °C for 2 h. Individual fractions were analysed by SDS-PAGE and two-dimensional electrophoresis. Western blotting with mouse anti-Hsp70 and anti-Hsp60 mAbs was used to identify the proteins. Electrophoretic analysis of the heat-treated cells detected Hsp70 in all three fractions, cytoplasmic, periplasmic and membrane, which was confirmed by Western blotting. The proteins obtained had diverse localizations in the pH gradient in two-dimensional electrophoresis, which may indicate changes in their conformation and physical properties leading to stabilization and protection of intracellular structures in stress conditions. The presence of these Hsps in different cell fractions indicates a very strong protective adaptation in the bacteria in unfavourable conditions, which is critical for the organism infected by them.

  17. Identification and expression analysis of heat shock transcription factors in the wild Chinese grapevine (Vitis pseudoreticulata).

    Science.gov (United States)

    Hu, Yang; Han, Yong-Tao; Zhang, Kai; Zhao, Feng-Li; Li, Ya-Juan; Zheng, Yi; Wang, Yue-Jin; Wen, Ying-Qiang

    2016-02-01

    Heat shock transcription factors (Hsfs) are known to play pivotal roles in the adaptation of plants to heat stress and other stress stimuli. While grapevine (Vitis vinifera L.) is one of the most important fruit crops worldwide, little is known about the Hsf family in Vitis spp. Here, we identified nineteen putative Hsf genes (VviHsfs) in Vitis spp based on the 12 × grape genome (V. vinifera L.). Phylogenetic analysis revealed three classes of grape Hsf genes (classes A, B, and C). Additional comparisons between grape and Arabidopsis thaliana demonstrated that several VviHsfs genes occurred in corresponding syntenic blocks of Arabidopsis. Moreover, we examined the expression profiles of the homologs of the VviHsfs genes (VpHsfs) in the wild Chinese Vitis pseudoreticulata accession Baihe-35-1, which is tolerant to various environmental stresses. Among the nineteen VpHsfs, ten VpHsfs displayed lower transcript levels under non-stress conditions and marked up-regulation during heat stress treatment; several VpHsfs also displayed altered expression levels in response to cold, salt, and hormone treatments, suggesting their versatile roles in response to stress stimuli. In addition, eight VpHsf-GFP fusion proteins showed differential subcellular localization in V. pseudoreticulata mesophyll protoplasts. Taken together, our data may provide an important reference for further studies of Hsf genes in Vitis spp.

  18. Reduction of RNA A-to-I editing in Drosophila acclimated to heat shock

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    Joel Stocker

    2013-09-01

    Full Text Available Although an increasing number of RNA adenosine-to-inosine (A-to-I editing sites are being discovered, how the editing frequencies of these sites are modulated to fine-tune protein function in adaptive responses is not well understood. A previous study screening for heat tolerance in Drosophila mutants discovered a hypnos-2 mutant strain that was later found to be defective in dADAR, the Drosophila gene encoding the A-to-I editing enzyme. This supports the hypothesis that cells and organisms respond to stressful environments by ADAR (adenosine deaminase acting on RNA-mediated RNA editing. Here, we investigated changes in the RNA A-to-I editing frequencies of 30 Drosophila nervous system targets in response to heat shock, a stress acclimatization that requires the dADAR function. To our surprise, most of these nervous system editing targets showed reduced editing. Our results suggest that a change in RNA editing pattern is a mechanism by which organisms acclimate to drastic environmental change. However, how RNA editing confers heat resistance is more complicated and requires further investigation.

  19. Effect of sequential heat and cold shocks on nuclear phenotypes of the blood-sucking insect, Panstrongylus megistus (Burmeister (Hemiptera, Reduviidae

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    Garcia Simone L

    2002-01-01

    Full Text Available Thermal shocks induce changes in the nuclear phenotypes that correspond to survival (heterochromatin decondensation, nuclear fusion or death (apoptosis, necrosis responses in the Malpighian tubules of Panstrongylus megistus. Since thermal tolerance increased survival and molting rate in this species following sequential shocks, we investigated whether changes in nuclear phenotypes accompanied the insect survival response to sequential thermal shocks. Fifth instar nymphs were subjected to a single heat (35 or 40°C, 1 h or cold (5 or 0°C, 1 h shock and then subjected to a second shock for 12 h at 40 or 0°C, respectively, after 8, 18, 24 and 72 h at 28°C (control temperature. As with specimen survival, sequential heat and cold shocks induced changes in frequency of the mentioned nuclear phenotypes although their patterns differed. The heat shock tolerance involved decrease in apoptosis simultaneous to increase in cell survival responses. Sequential cold shocks did not involve cell/nuclear fusion and even elicited increase in necrosis with advancing time after shocks. The temperatures of 40 and 0ºC were more effective than the temperatures of 35 and 5ºC in eliciting the heat and cold shock tolerances, respectively, as shown by cytological analysis of the nuclear phenotypes. It is concluded that different sequential thermal shocks can trigger different mechanisms of cellular protection against stress in P. megistus, favoring the insect to adapt to various ecotopes.

  20. Topoisomerase activity during the heat shock response in Escherichia coli K-12.

    Science.gov (United States)

    Camacho-Carranza, R; Membrillo-Hernández, J; Ramírez-Santos, J; Castro-Dorantes, J; Chagoya de Sánchez, V; Gómez-Eichelmann, M C

    1995-01-01

    During the upshift of temperature from 30 to 42, 45, 47, or 50 degrees C, an increase in the level of supercoiling of a reporter plasmid was observed. This increase was present in groE and dnaK mutants but was inhibited in cells treated with chloramphenicol and novobiocin. The intracellular [ATP]/[ADP] ratio increased rapidly after an upshift in temperature from 30 to 47 degrees C and then decreased to reach a level above that observed at 30 degrees C. These results suggest that gyrase and proteins synthesized during heat shock are responsible for the changes seen in plasmid supercoiling. Proteins GroE and DnaK are probably not involved in this phenomenon. PMID:7768879

  1. Modulation of heat shock protein response in SH-SY5Y by mobile phone microwaves

    Institute of Scientific and Technical Information of China (English)

    Emanuele; Calabrò; Salvatore; Condello; Monica; Currò; Nadia; Ferlazzo; Daniela; Caccamo; Salvatore; Magazù; Riccardo; Ientile

    2012-01-01

    AIM: To investigate putative biological damage caused by GSM mobile phone frequencies by assessing electromagnetic fields during mobile phone working. METHODS: Neuron-like cells, obtained by retinoicacid-induced differentiation of human neuroblastoma SH-SY5Y cells, were exposed for 2 h and 4 h to microwaves at 1800 MHz frequency bands. RESULTS: Cell stress response was evaluated by MTT assay as well as changes in the heat shock protein expression (Hsp20, Hsp27 and Hsp70) and caspase-3 activity levels, as biomarkers of apoptotic pathway. Under our experimental conditions, neither cell viability nor Hsp27 expression nor caspase-3 activity was significantly changed. Interestingly, a significant decrease in Hsp20 expression was observed at both times of exposure, whereas Hsp70 levels were significantly increased only after 4 h exposure. CONCLUSION: The modulation of the expression of Hsps in neuronal cells can be an early response to radiofrequency microwaves.

  2. Synthesis of heat shock proteins in rat brain cortex after transient ischemia.

    Science.gov (United States)

    Dienel, G A; Kiessling, M; Jacewicz, M; Pulsinelli, W A

    1986-08-01

    Cell-free protein synthesis and two-dimensional gel autoradiography were used to characterize early postischemic protein synthesis in rat neocortex. Severe forebrain ischemia was induced for 30 min (four-vessel occlusion model) and followed by 3 h of recirculation. Polysomes were isolated from the cerebral cortex, translated in vitro in a reticulocyte system, and analyzed by two-dimensional gel electrophoresis. The translation products of postischemic polysomes included a major new protein family (70 kDa) with multiple isoelectric variants that was found to comigrate with the 68- to 70-kDa "heat shock" protein synthesized from polysomes of hyperthermic rats. Two other stress proteins (93 and 110 kDa) also appeared to be synthesized in increased amounts after ischemia. A complement of proteins that was indistinguishable from that of controls was also synthesized after ischemia, indicating that messenger ribonucleic acid coding for most brain proteins is preserved after ischemia and is bound to polysomes.

  3. Expression of heat shock protein 72 in atrophied rat skeletal muscles

    Science.gov (United States)

    Oishi, Y.; Ishihara, A.; Talmadge, R. J.; Ohira, Y.; Taniguchi, K.; Matsumoto, H.; Roy, R. R.; Edgerton, V. R.

    2001-01-01

    Changes in the expression of heat shock protein 72 (HSP72) in response to atrophic-inducing perturbations of muscle involving chronic mechanical unloading and denervation were determined. Adult male Wistar rats were assigned randomly to a sedentary cage control (CON), hind limb unloading (HU, via tail suspension), HU plus tenotomy (HU + TEN), HU plus denervation (HU + DEN), or HU + TEN + DEN group. Tenotomy and DEN involved cutting the Achilles tendon and removing a segment of the sciatic nerve, respectively. After 5 days, HSP72 levels in the soleus of the HU + DEN and HU + TEN + DEN groups were 42 (P rat plantarflexor are responsive to a chronic decrease in the levels of loading and/or activation and suggest that the neuromuscular activity level and the presence of innervation of a muscle are important factors that induce HSP72 expression.

  4. Small heat shock protein Hsp27 is required for proper heart tube formation.

    Science.gov (United States)

    Brown, Daniel D; Christine, Kathleen S; Showell, Christopher; Conlon, Frank L

    2007-11-01

    The small heat shock protein Hsp27 has been shown to be involved in a diverse array of cellular processes, including cellular stress response, protein chaperone activity, regulation of cellular glutathione levels, apoptotic signaling, and regulation of actin polymerization and stability. Furthermore, mutation within Hsp27 has been associated with the human congenital neuropathy Charcot-Marie Tooth (CMT) disease. Hsp27 is known to be expressed in developing embryonic tissues; however, little has been done to determine the endogenous requirement for Hsp27 in developing embryos. In this study, we show that depletion of XHSP27 protein results in a failure of cardiac progenitor fusion resulting in cardia bifida. Furthermore, we demonstrate a concomitant disorganization of actin filament organization and defects in myofibril assembly. Moreover, these defects are not associated with alterations in specification or differentiation. We have thus demonstrated a critical requirement for XHSP27 in developing cardiac and skeletal muscle tissues.

  5. Heat shock protein 70 chaperoned alpha-fetoprotein in human hepatocellular carcinoma cell line BEL-7402

    Institute of Scientific and Technical Information of China (English)

    Xiao-Ping Wang; Qiao-Xia Wang; Hai-Yan Li; Rui-Fen Chen

    2005-01-01

    AIM: To investigate the interaction between heat shock protein 70 (HSP70) and α-fetoprotein (AFP) in human hepatocellular carcinoma (HCC) cell line BEL7402.METHODS: The expression and localization of HSP70 and AFP in human HCC cell line BEL-7402 were determined by immunocytochemistry and indirect immunofluorescence cytochemical staining. The interaction between HSP70 and AFP in HCC cells was analyzed by immunoprecipitation and Western blot.RESULTS: Immunocytochemical staining detection showed that HCC cell BEL-7402 expressed a high level of HSP70 and AFP synchronously. Both were stained in cell plasma.AFP existed in the immunoprecipitate of anti-HSP70 mAb,while there was HSP70 in the immunoprecipitate of antiAFP mAb.CONCLUSION: HSP70 chaperones AFP in human HCCcell BEL-7402. The interaction between HSP70 and AFP in human HCC cell can be a new route to study the pathogenesis and immunotherapy of HCC.

  6. Innate and Adaptive Responses to Heat Shock Proteins in Behcet’s Disease

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    H. Direskeneli

    2013-01-01

    Full Text Available Behcet’s disease (BD is a systemic, chronic inflammatory disorder with both innate and adaptive immune responses. Heat shock proteins (HSP are highly conserved molecules in different species with scavenger activity and involved in correct folding of newly synthesized proteins. T and B cell responses against HSPs are observed in BD patients in both αβ and γδ T-cell populations. 60-kD HSP (HSP60 is also shown to be recognized by pattern recognition receptors such as toll-like receptors (TLR and is suggested to be an endogenous “danger” signal to the immune system with rapid inflammatory cytokine releases and enhancement of adaptive Th1-type responses. Elucidating the exact role of HSPs in BD pathogenesis might pave the way to less toxic therapeutic approaches to BD, such as antibacterial therapies and immunomodulation.

  7. Heat-shock protein dysregulation is associated with functional and pathological TDP-43 aggregation

    Science.gov (United States)

    Chang, Hsiang-Yu; Hou, Shin-Chen; Way, Tzong-Der; Wong, Chi-Huey; Wang, I.-Fan

    2013-11-01

    Conformational disorders are involved in various neurodegenerative diseases. Reactive oxygen species (ROS) are the major contributors to neurodegenerative disease; however, ROS that affect the structural changes in misfolded disease proteins have yet to be well characterized. Here we demonstrate that the intrinsic propensity of TDP-43 to aggregate drives the assembly of TDP-43-positive stress granules and soluble toxic TDP-43 oligomers in response to a ROS insult via a disulfide crosslinking-independent mechanism. Notably, ROS-induced TDP-43 protein assembly correlates with the dynamics of certain TDP-43-associated chaperones. The heat-shock protein (HSP)-90 inhibitor 17-AAG prevents ROS-induced TDP-43 aggregation, alters the type of TDP-43 multimers and reduces the severity of pathological TDP-43 inclusions. In summary, our study suggests that a common mechanism could be involved in the pathogenesis of conformational diseases that result from HSP dysregulation.

  8. Stability of lysozyme in aqueous extremolyte solutions during heat shock and accelerated thermal conditions.

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    Christina Avanti

    Full Text Available The purpose of this study was to investigate the stability of lysozyme in aqueous solutions in the presence of various extremolytes (betaine, hydroxyectoine, trehalose, ectoine, and firoin under different stress conditions. The stability of lysozyme was determined by Nile red Fluorescence Spectroscopy and a bioactivity assay. During heat shock (10 min at 70°C, betaine, trehalose, ectoin and firoin protected lysozyme against inactivation while hydroxyectoine, did not have a significant effect. During accelerated thermal conditions (4 weeks at 55°C, firoin also acted as a stabilizer. In contrast, betaine, hydroxyectoine, trehalose and ectoine destabilized lysozyme under this condition. These findings surprisingly indicate that some extremolytes can stabilize a protein under certain stress conditions but destabilize the same protein under other stress conditions. Therefore it is suggested that for the screening extremolytes to be used for protein stabilization, an appropriate storage conditions should also be taken into account.

  9. Targeting Heat Shock Protein 90 for the Treatment of Malignant Pheochromocytoma

    Science.gov (United States)

    Giubellino, Alessio; Sourbier, Carole; Lee, Min-Jung; Scroggins, Brad; Bullova, Petra; Landau, Michael; Ying, Weiwen; Neckers, Len

    2013-01-01

    Metastatic pheochromocytoma represents one of the major clinical challenges in the field of neuroendocrine oncology. Recent molecular characterization of pheochromocytoma suggests new treatment options with targeted therapies. In this study we investigated the 90 kDa heat shock protein (Hsp90) as a potential therapeutic target for advanced pheochromocytoma. Both the first generation, natural product Hsp90 inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG, tanespimycin), and the second-generation synthetic Hsp90 inhibitor STA-9090 (ganetespib) demonstrated potent inhibition of proliferation and migration of pheochromocytoma cell lines and induced degradation of key Hsp90 clients. Furthermore, ganetespib induced dose-dependent cytotoxicity in primary pheochromocytoma cells. Using metastatic models of pheochromocytoma, we demonstrate the efficacy of 17-AAG and ganetespib in reducing metastatic burden and increasing survival. Levels of Hsp70 in plasma from the xenograft studies served as a proximal biomarker of drug treatment. Our study suggests that targeting Hsp90 may benefit patients with advanced pheochromocytoma. PMID:23457505

  10. Simulation of intense heating and shock hydrodynamics in free-moving liquid targets.

    Energy Technology Data Exchange (ETDEWEB)

    Hassanein, A.

    1999-08-27

    Recently, significant interest has focused on the use of free or open liquid-metal targets flowing with high velocities in various nuclear and high-energy physics applications such as the ISOLDE and muon collider projects. This is because the heat generated in solid targets due to beam bombardment cannot be removed easily and the resulting thermal shock damage is a serious problem. The behavior of a free-moving liquid mercury or gallium jet due to a proton beam deposition in a strong magnetic field has been modeled and analyzed for the muon collider project. Free liquid-metal jets offer significant advantages over conventional solid targets, particularly for the more demanding and challenging high-power applications.

  11. Regulatory effect of heat shock protein 70 in stress-induced rat intestinal epithelial barrier dysfunction

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    Stevie Struiksma

    2009-06-01

    Full Text Available Background: Psychological stress is one of the factors associated with many human diseases; the mechanisms need to be further understood. Methods: Rats were subjected to chronic water avoid stress. Intestinal epithelial heat shock protein (HSP 70 was evaluated. The intestinal epithelial permeability was examined with Ussing chamber technique. Results: HSP70 was detected in normal intestinal epithelial cells. Psychological stress decreased HSP70 in the intestinal epithelial cells that correlated with the stress-induced intestinal epithelial hyperpermeability. Pretreatment with HSP70 abrogated stress-induced intestinal barrier dysfunction. Conclusions: Chronic stress inhibits HSP70 activity in rat intestinal epithelial layer that is associated with intestinal epithelial barrier dysfunction, which can be prevented by pretreatment with HSP70 protein.

  12. The Stress Granule RNA-Binding Protein TIAR-1 Protects Female Germ Cells from Heat Shock in Caenorhabditis elegans

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    Gabriela Huelgas-Morales

    2016-04-01

    Full Text Available In response to stressful conditions, eukaryotic cells launch an arsenal of regulatory programs to protect the proteome. One major protective response involves the arrest of protein translation and the formation of stress granules, cytoplasmic ribonucleoprotein complexes containing the conserved RNA-binding proteins TIA-1 and TIAR. The stress granule response is thought to preserve mRNA for translation when conditions improve. For cells of the germline—the immortal cell lineage required for sexual reproduction—protection from stress is critically important for perpetuation of the species, yet how stress granule regulatory mechanisms are deployed in animal reproduction is incompletely understood. Here, we show that the stress granule protein TIAR-1 protects the Caenorhabditis elegans germline from the adverse effects of heat shock. Animals containing strong loss-of-function mutations in tiar-1 exhibit significantly reduced fertility compared to the wild type following heat shock. Analysis of a heat-shock protein promoter indicates that tiar-1 mutants display an impaired heat-shock response. We observed that TIAR-1 was associated with granules in the gonad core and oocytes during several stressful conditions. Both gonad core and oocyte granules are dynamic structures that depend on translation; protein synthesis inhibitors altered their formation. Nonetheless, tiar-1 was required for the formation of gonad core granules only. Interestingly, the gonad core granules did not seem to be needed for the germ cells to develop viable embryos after heat shock. This suggests that TIAR-1 is able to protect the germline from heat stress independently of these structures.

  13. The expression and function of hsp30-like small heat shock protein genes in amphibians, birds, fish, and reptiles.

    Science.gov (United States)

    Heikkila, John J

    2017-01-01

    Small heat shock proteins (sHSPs) are a superfamily of molecular chaperones with important roles in protein homeostasis and other cellular functions. Amphibians, reptiles, fish and birds have a shsp gene called hsp30, which was also referred to as hspb11 or hsp25 in some fish and bird species. Hsp30 genes, which are not found in mammals, are transcribed in response to heat shock or other stresses by means of the heat shock factor that is activated in response to an accumulation of unfolded protein. Amino acid sequence analysis revealed that representative HSP30s from different classes of non-mammalian vertebrates were distinct from other sHSPs including HSPB1/HSP27. Studies with amphibian and fish recombinant HSP30 determined that they were molecular chaperones since they inhibited heat- or chemically-induced aggregation of unfolded protein. During non-mammalian vertebrate development, hsp30 genes were differentially expressed in selected tissues. Also, heat shock-induced stage-specific expression of hsp30 genes in frog embryos was regulated at the level of chromatin structure. In adults and/or tissue culture cells, hsp30 gene expression was induced by heat shock, arsenite, cadmium or proteasomal inhibitors, all of which enhanced the production of unfolded/damaged protein. Finally, immunocytochemical analysis of frog and chicken tissue culture cells revealed that proteotoxic stress-induced HSP30 accumulation co-localized with aggresome-like inclusion bodies. The congregation of damaged protein in aggresomes minimizes the toxic effect of aggregated protein dispersed throughout the cell. The current availability of probes to detect the presence of hsp30 mRNA or encoded protein has resulted in the increased use of hsp30 gene expression as a marker of proteotoxic stress in non-mammalian vertebrates.

  14. Molecular cloning, characterization and functional analysis of a heat shock protein 70 gene in Cyclina sinensis.

    Science.gov (United States)

    Ren, Yipeng; Pan, Heting; Yang, Ying; Pan, Baoping; Bu, Wenjun

    2016-11-01

    Heat shock protein 70 (HSP70) is an important member of the heat shock protein superfamily and is involved in protecting organisms against various stressors. In the present study, we used RACE to clone a full-length Cyclina sinensis HSP70 cDNA termed CsHSP70. The full length of the CsHSP70 cDNA was 2308 bp, with a 5' untranslated region (UTR) of 42 bp, a 3' UTR of 268 bp, and an open reading frame (ORF) of 1998 bp encoding a polypeptide of 655 amino acids with an estimated molecular mass of 72.75 kDa and an estimated isoelectric point of 5.48. Quantitative real-time PCR was employed to analyze the tissue distribution and temporal expression of the CsHSP70 gene after bacterial challenge and cadmium (Cd) exposure. The CsHSP70 mRNA transcript was expressed ubiquitously in five examined tissues, with the highest expression in hemocytes (P < 0.05) and with the lowest expression in the hepatopancreas. Furthermore, the expression level of CsHSP70 in hemocytes at 3 h after Vibrio anguillarum challenge was extremely significantly up-regulated (P < 0.01). Moreover, the CsHSP70 transcript was up-regulated significantly following exposure to a safe Cd concentration (0.1 mg/L). Finally, after the CsHSP70 gene was silenced by RNA interference, the expression of the CsTLR13 and CsMyD88 genes were extremely significantly decreased (P < 0.01). The results indicated that CsHSP70 could play an important role in mediating the environmental stress and immune responses, and regulating TLR signaling pathway in C. sinensis.

  15. Inactivation of GABAA receptor is related to heat shock stress response in organism model Caenorhabditis elegans.

    Science.gov (United States)

    Camargo, Gabriela; Elizalde, Alejandro; Trujillo, Xochitl; Montoya-Pérez, Rocío; Mendoza-Magaña, María Luisa; Hernandez-Chavez, Abel; Hernandez, Leonardo

    2016-09-01

    The mechanisms underlying oxidative stress (OS) resistance are not completely clear. Caenorhabditis elegans (C. elegans) is a good organism model to study OS because it displays stress responses similar to those in mammals. Among these mechanisms, the insulin/IGF-1 signaling (IIS) pathway is thought to affect GABAergic neurotransmission. The aim of this study was to determine the influence of heat shock stress (HS) on GABAergic activity in C. elegans. For this purpose, we tested the effect of exposure to picrotoxin (PTX), gamma-aminobutyric acid (GABA), hydrogen peroxide, and HS on the occurrence of a shrinking response (SR) after nose touch stimulus in N2 (WT) worms. Moreover, the effect of HS on the expression of UNC-49 (GABAA receptor ortholog) in the EG1653 strain and the effect of GABA and PTX exposure on HSP-16.2 expression in the TJ375 strain were analyzed. PTX 1 mM- or H2O2 0.7 mM-exposed worms displayed a SR in about 80 % of trials. GABA exposure did not cause a SR. HS prompted the occurrence of a SR as did PTX 1 mM or H2O2 0.7 mM exposure. In addition, HS increased UNC-49 expression, and PTX augmented HSP-16.2 expression. Thus, the results of the present study suggest that oxidative stress, through either H2O2 exposure or application of heat shock, inactivates the GABAergic system, which subsequently would affect the oxidative stress response, perhaps by enhancing the activity of transcription factors DAF-16 and HSF-1, both regulated by the IIS pathway and related to hsp-16.2 expression.

  16. Role of heat shock factor-1 activation in the doxorubicin-induced heart failure in mice.

    Science.gov (United States)

    Vedam, Kaushik; Nishijima, Yoshinori; Druhan, Lawrence J; Khan, Mahmood; Moldovan, Nicanor I; Zweier, Jay L; Ilangovan, Govindasamy

    2010-06-01

    Treating cancer patients with chemotherapeutics, such as doxorubicin (Dox), cause dilated cardiomyopathy and congestive heart failure because of oxidative stress. On the other hand, heat shock factor-1 (HSF-1), a transcription factor for heat shock proteins (Hsps), is also known to be activated in response to oxidative stress. However, the possible role of HSF-1 activation and the resultant Hsp25 in chemotherapeutic-induced heart failure has not been investigated. Using HSF-1 wild-type (HSF-1(+/+)) and knock-out (HSF-1(-/-)) mice, we tested the hypothesis that activation of HSF-1 plays a role in the development of Dox-induced heart failure. Higher levels of Hsp25 and its phosphorylated forms were found in the failing hearts of Dox-treated HSF-1(+/+) mice. More than twofold increase in Hsp25 mRNA level was found in Dox-treated hearts. Proteomic analysis showed that there is accumulation and aggregation of Hsp25 in Dox-treated failing hearts. Additionally, Hsp25 was found to coimmunoprecipitate with p53 and vice versa. Further studies indicated that the Dox-induced higher levels of Hsp25 transactivated p53 leading to higher levels of the pro-apoptotic protein Bax, but other p53-related proteins remained unaltered. Moreover, HSF-1(-/-) mice showed significantly reduced Dox-induced heart failure and higher survival rate, and there was no change in Bax upon treating with Dox in HSF-1(-/-) mice. From these results we propose a novel mechanism for Dox-induced heart failure: increased expression of Hsp25 because of oxidant-induced activation of HSF-1 transactivates p53 to increase Bax levels, which leads to heart failure.

  17. Removal of silver nanoparticles using live and heat shock Aspergillus niger cultures.

    Science.gov (United States)

    Gomaa, Ola M

    2014-06-01

    Silver nanoparticles (SNPs) are extensively used in many industrial and medical applications; however, the impact of their release in the environment is still considered an understudied field. In the present work, SNPs present in aqueous lab waste water (average size of 30 nm) were used to determine their impact on microflora if released in soil rhizosphere and sewage waste water. The results showed that 24 h incubation with different SNP concentrations resulted in a 2.6-fold decrease for soil rhizosphere microflora and 7.45-fold decrease for sewage waste water microflora, both at 24 ppm. Live and heat shock (50 and 70 °C) Aspergillus niger cultures were used to remove SNP waste, the results show 76.6, 81.74 and 90.8 % SNP removal, respectively after 3 h incubation. There was an increase in the log total bacterial count again after SNP removal by A. niger in the following order: live A. niger niger niger. The pH value decreased from 5.8 to 3.8 in the same order suggesting the production of an acid in the culture media. Scanning electron microscopy images showed agglomeration and/or complexation of SNP particles, in a micron size, in between the fungal mycelia, hence settling on and in between the mycelial network. The results suggest that silver was reduced again and agglomerated and/or chelated together in its oxidized form by an acid in A. niger media. More studies are recommended to determine the acid and the heat shock proteins to confirm the exact mode of action.

  18. Specific Genetic Immunotherapy Induced by Recombinant Vaccine Alpha-Fetoprotein-Heat Shock Protein 70 Complex

    Science.gov (United States)

    Wang, Xiaoping; Lin, Huanping; Wang, Qiaoxia

    Purposes: To construct a recombinant vaccine alpha-fetoprotein (AFP)-heat shock protein (HSP70) complex, and study its ability to induce specific CTL response and its protective effect against AFP-producing tumor. Material/Methods: A recombinant vaccine was constructed by conjugating mouse alpha-fetoprotein to heat shock protein 70. By way of intracutaneous injection, mice were primed and boosted with recombinant vaccine mAFP/HSP70, whereas single mAFP or HSP70 injection as controls. The ELISPOT and ELISA were used to measure the frequency of cells producing the cytokine IFN-γ in splenocytes and the level of anti-AFP antibody of serum from immunized mice respectively. In vivo tumor challenge were carried out to assess the immune effect of the recombinant vaccine. Results: By recombinant mAFP/HSP70 vaccine immunization, the results of ELISPOT and ELISA showed that the number of splenic cells producing IFN-γ and the level of anti-AFP antibody of serum were significantly higher in mAFP/HSP70 group than those in mAFP and HSP70 groups (108.50±11.70 IFN-γ spots/106 cells vs 41.60±10.40 IFN-γ spots/106 cells, 7.32±3.14 IFN-γ spots/106 cells, Precombinant mAFP/HSP70 vaccine could generate effective antitumor immunity on AFP-producing tumor. The recombined mAFP/HSP70 vaccine may be suitable for serving as an immunotherapy for hepatocellular carcinoma.

  19. Activity of heat shock genes' promoters in thermally contrasting animal species.

    Science.gov (United States)

    Astakhova, Lyubov N; Zatsepina, Olga G; Funikov, Sergei Yu; Zelentsova, Elena S; Schostak, Natalia G; Orishchenko, Konstantin E; Evgen'ev, Michael B; Garbuz, David G

    2015-01-01

    Heat shock gene promoters represent a highly conserved and universal system for the rapid induction of transcription after various stressful stimuli. We chose pairs of mammalian and insect species that significantly differ in their thermoresistance and constitutive levels of Hsp70 to compare hsp promoter strength under normal conditions and after heat shock (HS). The first pair includes the HSPA1 gene promoter of camel (Camelus dromedarius) and humans. It was demonstrated that the camel HSPA1A and HSPA1L promoters function normally in vitro in human cell cultures and exceed the strength of orthologous human promoters under basal conditions. We used the same in vitro assay for Drosophila melanogaster Schneider-2 (S2) cells to compare the activity of the hsp70 and hsp83 promoters of the second species pair represented by Diptera, i.e., Stratiomys singularior and D. melanogaster, which dramatically differ in thermoresistance and the pattern of Hsp70 accumulation. Promoter strength was also monitored in vivo in D. melanogaster strains transformed with constructs containing the S. singularior hsp70 ORF driven either by its own promoter or an orthologous promoter from the D. melanogaster hsp70Aa gene. Analysis revealed low S. singularior hsp70 promoter activity in vitro and in vivo under basal conditions and after HS in comparison with the endogenous promoter in D. melanogaster cells, which correlates with the absence of canonical GAGA elements in the promoters of the former species. Indeed, the insertion of GAGA elements into the S. singularior hsp70 regulatory region resulted in a dramatic increase in promoter activity in vitro but only modestly enhanced the promoter strength in the larvae of the transformed strains. In contrast with hsp70 promoters, hsp83 promoters from both of the studied Diptera species demonstrated high conservation and universality.

  20. CHIP Knockdown Reduced Heat Shock Response and Protein Quality Control Capacity in Lens Epithelial Cells.

    Science.gov (United States)

    Zhang, W; Liu, Z; Bao, X; Qin, Y; Taylor, A; Shang, F; Wu, M

    2015-01-01

    Protein quality control (PQC) systems, including molecular chaperones and ubiquitin-proteasome pathway (UPP), plays an important role in maintaining intracellular protein homeostasis. Carboxyl terminus of Hsc70- interacting protein (CHIP) links the chaperone and UPPs, thus contributing to the repair or removal of damaged proteins. Over-expression of CHIP had previously been used to protect cells from environmental stress. In order to gain a more physiologic mechanism of the advantage conferred by CHIP, we induced a CHIP knockdown and monitored the ability of cells to cope with environmental stress. To knockdown CHIP, the human lens epithelial cell line HLE B3 was transfected with lentiviral particles that encode a CHIP short hairpin RNA (shRNA) or negative control lentiviral particles. Stable CHIP-knock down cells (KD) and negative control cells (NC) were selected with puromycin. After exposure to heat shock stress, there was no change observed in the expression of Hsp90. In contrast, Hsp70 levels increased significantly in NC cells but less so in KD cells. Hsp27 levels also increased after heat shock, but only in NC cells. Protein ubiquitination was reduced when CHIP was knocked down. CHIP knockdown reduced the ability to clear aggregation proteins. When same levels of aggregation-prone RFP-mutant crystallin fusion protein, RFP/V76D-γD, was expressed, there was ~9- fold more aggregates in KD cells as compared to that observed in NC cells. Furthermore, KD cells were more sensitive to toxicity of amino acid analog canavanine as compared to NC cells. Together, these data indicate that CHIP is required for PQC and that CHIP knockdown diminished cellular PQC capacity in lens cells.

  1. Constitutively active heat shock factor 1 enhances glucose-driven insulin secretion.

    Science.gov (United States)

    Uchiyama, Tsuyoshi; Tomono, Shoichi; Utsugi, Toshihiro; Ohyama, Yoshio; Nakamura, Tetsuya; Tomura, Hideaki; Kawazu, Shoji; Okajima, Fumikazu; Kurabayashi, Masahiko

    2011-06-01

    Weak pancreatic β-cell function is a cause of type 2 diabetes mellitus. Glucokinase regulates insulin secretion via phosphorylation of glucose. The present study focused on a system for the self-protection of pancreatic cell by expressing heat shock factor (HSF) and heat shock protein (HSP) to improve insulin secretion without inducing hypoglycemia. We previously generated a constitutively active form of human HSF1 (CA-hHSF1). An adenovirus expressing CA-hHSF1 using the cytomegalovirus promoter was generated to infect mouse insulinoma cells (MIN6 cells). An adenovirus expressing CA-hHSF1 using a human insulin promoter (Ins-CA-hHSF1) was also generated to infect rats. We investigated whether CA-hHSF1 induces insulin secretion in MIN6 cells and whether Ins-CA-hHSF1 can improve blood glucose and serum insulin levels in healthy Wister rats and type 2 diabetes mellitus model rats. CA-hHSF1 expression increased insulin secretion 1.27-fold compared with the overexpression of wild-type hHSF1 in MIN6 cells via induction of HSP90 expression and subsequent activation of glucokinase. This mechanism is associated with activation of both glucokinase and neuronal nitric oxide synthase. Ins-CA-hHSF1 improved blood glucose levels in neonatal streptozotocin-induced diabetic rats. Furthermore, Ins-CA-hHSF1 reduced oral glucose tolerance testing results in healthy Wister rats because of an insulin spike at 15 minutes; however, it did not induce hypoglycemia. CA-hHSF1 induced insulin secretion both in vitro and in vivo. These findings suggest that gene therapy with Ins-CA-hHSF1 will be able to be used to treat patients with type 2 diabetes mellitus and impaired glucose tolerance without causing hypoglycemia at fasting. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. Protein kinase Cmu plays an essential role in hypertonicity-induced heat shock protein 70 expression.

    Science.gov (United States)

    Lim, Yun Sook; Lee, Jae Seon; Huang, Tai Qin; Seo, Jeong Sun

    2008-12-31

    Heat shock protein 70 (HSP70), which evidences important functions as a molecular chaperone and anti-apoptotic molecule, is substantially induced in cells exposed to a variety of stresses, including hypertonic stress, heavy metals, heat shock, and oxidative stress, and prevents cellular damage under these conditions. However, the molecular mechanism underlying the induction of HSP70 in response to hypertonicity has been characterized to a far lesser extent. In this study, we have investigated the cellular signaling pathway of HSP70 induction under hypertonic conditions. Initially, we applied a variety of kinase inhibitors to NIH3T3 cells that had been exposed to hypertonicity. The induction of HSP70 was suppressed specifically by treatment with protein kinase C (PKC) inhibitors (Gö6976 and GF109203X). As hypertonicity dramatically increased the phosphorylation of PKCmu, we then evaluated the role of PKCmu in hypertonicity-induced HSP70 expression and cell viability. The depletion of PKCmu with siRNA or the inhibition of PKCmu activity with inhibitors resulted in a reduction in HSP70 induction and cell viability. Tonicity-responsive enhancer binding protein (TonEBP), a transcription factor for hypertonicity-induced HSP70 expression, was translocated rapidly into the nucleus and was modified gradually in the nucleus under hypertonic conditions. When we administered treatment with PKC inhibitors, the mobility shift of TonEBP was affected in the nucleus. However, PKCmu evidenced no subcellular co-localization with TonEBP during hypertonic exposure. From our results, we have concluded that PKCmu performs a critical function in hypertonicity-induced HSP70 induction, and finally cellular protection, via the indirect regulation of TonEBP modification.

  3. Prophylactic Antitumor Effect of Mixed Heat Shock Proteins/Peptides in Mouse Sarcoma

    Institute of Scientific and Technical Information of China (English)

    Yu Wang; Shu-Yun Liu; Mei Yuan; Yu Tang; Quan-Yi Guo; Xue-Mei Cui; Xiang Sui

    2015-01-01

    Background:To develop a vaccine-based immunotherapy for sarcoma,we evaluated a mixture of heat shock proteins (mHSPs) as a vaccine for sarcoma treatment in a mouse model.Heat shock protein/peptides (HSP/Ps) are autoimmune factors that can induce both adaptive and innate immune responses;HSP/Ps isolated from tumors can induce antitumor immune activity when used as vaccines.Methods:In this study,we evaluated the effects of mHSP/Ps on prophylactic antitumor immunity.We extracted mHSP/Ps,including HSP60,HSP70,GP96,and HSP l 10,from the mouse sarcoma cell lines S 180 and MCA207 using chromatography.The immunity induced by mHSP/Ps was assessed using flow cytometry,ELISPOT,lactate dehydrogenase release,and enzyme-linked immunosorbent assay.Results:Of S180 sarcoma-beating mice immunized with mHSP/Ps isolated from S180 cells,41.2% showed tumor regression and long-term survival,with a tumor growth inhibition rate of 82.3% at 30 days.Of MCA207 sarcoma-bearing mice immunized with mHSP/Ps isolated from MCA207 cells,50% showed tumor regression and long-term survival with a tumor growth inhibition rate of 79.3%.All control mice died within 40 days.The proportions of natural killer cells,CD8+,and interferon-γ-secreting cells and tumor-specific cytotoxic T-lymphocyte activity were increased in the immunized group.Conclusions:Vaccination with a polyvalent mHSP/P cancer vaccine can induce an immunological response and a marked antitumor response to autologous tumors.This mHSP/P vaccine exerted greater antitumor effects than did HSPT0,HSP60,or tumor lysates alone.

  4. The Mesenchymal Precursor Cell Marker Antibody STRO-1 Binds to Cell Surface Heat Shock Cognate 70.

    Science.gov (United States)

    Fitter, Stephen; Gronthos, Stan; Ooi, Soo Siang; Zannettino, Andrew C W

    2016-12-27

    Since its discovery more than 25 years ago, the STRO-1 antibody has played a fundamental role in defining the hierarchical nature of mesenchymal precursor cells (MPC) and their progeny. STRO-1 antibody binding remains a hallmark of immature pluripotent MPC. Despite the significance of STRO-1 in the MPC field, the identity of the antigen has remained elusive. Using a combination of two-dimensional gel electrophoresis, coupled with Western blotting and Tandem mass spectroscopy, we have identified the STRO-1 antigen as heat shock cognate 70 (HSC70;HSPA8). STRO-1 binds to immune-precipitated HSC70 and siRNA-mediated knock down of HSPA8 reduced STRO-1 binding. STRO-1 surface binding does not correlate with HSC70 expression and sequestration of cholesterol reduces STRO-1 surface binding, suggesting that the plasma membrane lipid composition may be an important determinant in the presentation of HSC70 on the cell surface. HSC70 is present on the surface of STRO-1(+) but not STRO-1(-) cell lines as assessed by cell surface biotinylation and recombinant HSC70 blocks STRO-1 binding to the cell surface. The STRO-1 epitope on HSC70 was mapped to the ATPase domain using a series of deletion mutants in combination with peptide arrays. Deletion of the first four amino acids of the consensus epitope negated STRO-1 binding. Notably, in addition to HSC70, STRO-1 cross-reacts with heat shock protein 70 (HSP70), however all the clonogenic cell activity is restricted to the STRO-1(BRIGHT) /HSP70(-) fraction. These results provide important insight into the properties that define multipotent MPC and provide the impetus to explore the role of cell surface HSC70 in MPC biology. Stem Cells 2016.

  5. LDH inhibition impacts on heat shock response and induces senescence of hepatocellular carcinoma cells.

    Science.gov (United States)

    Manerba, Marcella; Di Ianni, Lorenza; Govoni, Marzia; Roberti, Marinella; Recanatini, Maurizio; Di Stefano, Giuseppina

    2017-07-15

    In normal cells, heat shock response (HSR) is rapidly induced in response to a variety of harmful conditions and represents one of the most efficient defense mechanism. In cancer tissues, constitutive activation converts HSR into a life-threatening process, which plays a major role in helping cell survival and proliferation. Overexpression of heat shock proteins (HSPs) has been widely reported in human cancers and was found to correlate with tumor progression. Hepatocellular carcinoma is one of the conditions in which HSR activation was shown to have the highest clinical significance. Transcription of HSPs is induced by HSF-1, which also activates glycolytic metabolism and increases the expression of LDH-A, the master regulator of the Warburg effect. In this paper, we tried to explore the relationship between HSR and LDH-A. In cultured hepatocellular carcinoma cells, by using two enzyme inhibitors (oxamate and galloflavin), we found that the reduction of LDH-A activity led to decreased level and function of the major HSPs involved in tumorigenesis. Galloflavin (a polyphenol) also inhibited the ATPase activity of two of the examined HSPs. Finally, hindering HSR markedly lowered the alpha-fetoprotein cellular levels and induced senescence. Specific inhibitors of single HSPs are currently under evaluation in different neoplastic diseases. However, one of the effects usually observed during treatment is a compensatory elevation of other HSPs, which decreases treatment efficacy. Our results highlight a connection between LDH and HSR and suggest LDH inhibition as a way to globally impact on this tumor promoting process. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Deciphering human heat shock transcription factor 1 regulation via post-translational modification in yeast.

    Directory of Open Access Journals (Sweden)

    Liliana Batista-Nascimento

    Full Text Available Heat shock transcription factor 1 (HSF1 plays an important role in the cellular response to proteotoxic stresses. Under normal growth conditions HSF1 is repressed as an inactive monomer in part through post-translation modifications that include protein acetylation, sumoylation and phosphorylation. Upon exposure to stress HSF1 homotrimerizes, accumulates in nucleus, binds DNA, becomes hyper-phosphorylated and activates the expression of stress response genes. While HSF1 and the mechanisms that regulate its activity have been studied for over two decades, our understanding of HSF1 regulation remains incomplete. As previous studies have shown that HSF1 and the heat shock response promoter element (HSE are generally structurally conserved from yeast to metazoans, we have made use of the genetically tractable budding yeast as a facile assay system to further understand the mechanisms that regulate human HSF1 through phosphorylation of serine 303. We show that when human HSF1 is expressed in yeast its phosphorylation at S303 is promoted by the MAP-kinase Slt2 independent of a priming event at S307 previously believed to be a prerequisite. Furthermore, we show that phosphorylation at S303 in yeast and mammalian cells occurs independent of GSK3, the kinase primarily thought to be responsible for S303 phosphorylation. Lastly, while previous studies have suggested that S303 phosphorylation represses HSF1-dependent transactivation, we now show that S303 phosphorylation also represses HSF1 multimerization in both yeast and mammalian cells. Taken together, these studies suggest that yeast cells will be a powerful experimental tool for deciphering aspects of human HSF1 regulation by post-translational modifications.

  7. Chalcones from Angelica keiskei: Evaluation of Their Heat Shock Protein Inducing Activities.

    Science.gov (United States)

    Kil, Yun-Seo; Choi, Seul-Ki; Lee, Yun-Sil; Jafari, Mahtab; Seo, Eun-Kyoung

    2015-10-23

    Five new chalcones, 4,2',4'-trihydroxy-3'-[(2E,5E)-7-methoxy-3,7-dimethyl-2,5-octadienyl]chalcone (1), (±)-4,2',4'-trihydroxy-3'-[(2E)-6-hydroxy-7-methoxy-3,7-dimethyl-2-octenyl]chalcone (2), 4,2',4'-trihydroxy-3'-[(2E)-3-methyl-5-(1,3-dioxolan-2-yl)-2-pentenyl]chalcone (3), 2',3'-furano-4-hydroxy-4'-methoxychalcone (4), and (±)-4-hydroxy-2',3'-(2,3-dihydro-2-methoxyfurano)-4'-methoxychalcone (5), were isolated from the aerial parts of Angelica keiskei Koidzumi together with eight known chalcones, 6-13, which were identified as (±)-4,2',4'-trihydroxy-3'-[(6E)-2-hydroxy-7-methyl-3-methylene-6-octenyl]chalcone (6), xanthoangelol (7), xanthoangelol F (8), xanthoangelol G (9), 4-hydroxyderricin (10), xanthoangelol D (11), xanthoangelol E (12), and xanthoangelol H (13), respectively. Chalcones 1-13 were evaluated for their promoter activity on heat shock protein 25 (hsp25, murine form of human hsp27). Compounds 1 and 6 activated the hsp25 promoter by 21.9- and 29.2-fold of untreated control at 10 μM, respectively. Further protein expression patterns of heat shock factor 1 (HSF1), HSP70, and HSP27 by 1 and 6 were examined. Compound 6 increased the expression of HSF1, HSP70, and HSP27 by 4.3-, 1.5-, and 4.6-fold of untreated control, respectively, without any significant cellular cytotoxicities, whereas 1 did not induce any expression of these proteins. As a result, 6 seems to be a prospective HSP inducer.

  8. Effects of chronic heat stress on plasma concentration of secreted heat shock protein 70 in growing feedlot cattle.

    Science.gov (United States)

    Gaughan, J B; Bonner, S L; Loxton, I; Mader, T L

    2013-01-01

    Sixty Angus steers (449.2±11.0 kg) with implanted body temperature (BT) transmitters were used in a 110-d study to determine the effect of chronic stress (housing, diet, and climate) on extracellular heat shock protein 70 (eHsp70) concentration in plasma. The steers were a subset of a larger study involving 164 steers. Before the start of the study (d -31), 63 steers were implanted with a BT transmitter between the internal abdominal muscle and the peritoneum at the right side flank. Steers were housed in 20 pens (10 with shade and 10 without). Within each pen, 3 steers had a transmitter, and BT was recorded at 30-min intervals throughout the study. On d 0, 30, 60, 90, and 110, steers were weighed, BCS assessed (1 to 9 scale in which 1=emaciated and 9=obese), and 10 mL of blood from the coccygeal vein was collected for determination of inducible heat shock protein 70 (Hsp70) concentration by ELISA. Climatic variables (ambient temperature, relative humidity, solar radiation, black globe temperature, and wind speed) were obtained every 30 min from an on-site weather station. The relationship between the climatic variables and Hsp70 concentration were examined. As we failed to detect an effect of shade, all data were pooled. Mean BT over the duration of the study was 39.6±0.10°C. Mean BT was lowest (38.7±0.10°C) on d 0 and highest on d 110 (40.2°C±0.10). The Hsp70 concentration was least on d 0 (2.33±0.47 ng/mL) and greatest on d 30 (8.08±0.78 ng/mL). The Hsp70 concentration decreased from d 30 but remained above the d-0 concentrations on d 60, 90, and 110. There was a strong relationship between Hsp70 concentration and ambient temperature (r2=0.86; P38.6°C. The Hsp70 concentration is a reliable indicator of chronic stress but is not a reliable indicator of a single stressor when animals are exposed to multiple chronic stressors.

  9. ClpB1 overproduction in Synechocystis sp. strain PCC 6803 increases tolerance to rapid heat shock.

    Science.gov (United States)

    Gonzalez-Esquer, C Raul; Vermaas, Wim F J

    2013-10-01

    ClpB1 is a heat shock protein known to disaggregate large protein complexes. Constitutive, 16-fold ClpB1 overproduction in the cyanobacterium Synechocystis sp. strain PCC 6803 increased cell survival by 20-fold when cultures were heated quickly (1°C/s) to 50°C and delayed cell death by an average of 3 min during incubation at high temperatures (>46°C). Cooverexpression of ClpB1 and another heat shock protein, DnaK2, further increased cell survival. According to immunocytochemistry results, ClpB1 is dispersed throughout the cytoplasm but is concentrated in specific areas and is more prevalent near thylakoid membranes. However, ClpB1 overproduction does not lead to a change in the morphology, chlorophyll content, or photosystem ratio. Whereas electron microscopy demonstrated that apparent protein aggregation occurred after heat treatment in the control strain, protein aggregate size was maintained in the ClpB1 overexpresser. Constitutive ClpB1 overproduction allows an earlier response to heat shock and protects from rapid heating of cultures.

  10. RhoA Activation Sensitizes Cells to Proteotoxic Stimuli by Abrogating the HSF1-Dependent Heat Shock Response

    NARCIS (Netherlands)

    Meijering, Roelien A. M.; Wiersma, Marit; van Marion, Denise M. S.; Zhang, Deli; Hoogstra-Berends, Femke; Dijkhuis, Anne-Jan; Schmidt, Martina; Wieland, Thomas; Kampinga, Harm H.; Henning, Robert H.; Brundel, Bianca J. J. M.

    2015-01-01

    Background The heat shock response (HSR) is an ancient and highly conserved program of stress-induced gene expression, aimed at reestablishing protein homeostasis to preserve cellular fitness. Cells that fail to activate or maintain this protective response are hypersensitive to proteotoxic stress.

  11. A novel computational approach of image analysis to quantify behavioural response to heat shock in Chironomus Ramosus larvae (Diptera: Chironomidae

    Directory of Open Access Journals (Sweden)

    Bimalendu B. Nath

    2015-07-01

    Full Text Available All living cells respond to temperature stress through coordinated cellular, biochemical and molecular events known as “heat shock response” and its genetic basis has been found to be evolutionarily conserved. Despite marked advances in stress research, this ubiquitous heat shock response has never been analysed quantitatively at the whole organismal level using behavioural correlates. We have investigated behavioural response to heat shock in a tropical midge Chironomus ramosus Chaudhuri, Das and Sublette. The filter-feeding aquatic Chironomus larvae exhibit characteristic undulatory movement. This innate pattern of movement was taken as a behavioural parameter in the present study. We have developed a novel computer-aided image analysis tool “Chiro” for the quantification of behavioural responses to heat shock. Behavioural responses were quantified by recording the number of undulations performed by each larva per unit time at a given ambient temperature. Quantitative analysis of undulation frequency was carried out and this innate behavioural pattern was found to be modulated as a function of ambient temperature. Midge larvae are known to be bioindicators of aquatic environments. Therefore, the “Chiro” technique can be tested using other potential biomonitoring organisms obtained from natural aquatic habitats using undulatory motion as a behavioural parameter.

  12. Induction of DnaK and GroEL heat shock proteins by fluoroquinolones in Escherichia coli.

    OpenAIRE

    Mizushima, T.; Matsuo, M.; Sekimizu, K

    1997-01-01

    Various fluoroquinolones (norfloxacin, enoxacin, ofloxacin, levofloxacin, and sparfloxacin) induce DnaK and GroEL heat shock proteins in Escherichia coli. The induction is transient, consistent with the kinetics of cellular DNA relaxation. The concentrations of fluoroquinolones required for induction are similar to those required for DNA relaxation and much higher than those required for cell death.

  13. MORPHOLOGY OF THE MITOCHONDRIA IN HEAT-SHOCK-PROTEIN-60 DEFICIENT FIBROBLASTS FROM MITOCHONDRIAL MYOPATHY PATIENTS - EFFECTS OF STRESS CONDITIONS

    NARCIS (Netherlands)

    HUCKRIEDE, A; HEIKEMA, A; SJOLLEMA, K; BRIONES, P; AGSTERIBBE, E

    1995-01-01

    We have described two mitochondrial (mt) myopathy patients with reduced activities of various mt enzymes associated with significantly decreased amounts of heat shock protein 60 (hsp60). Experimental evidence suggested that the lack of hsp60 was the primary defect. Since hsp60 is essential for the p

  14. Interactions of p60, a mediator of progesterone receptor assembly, with heat shock proteins hsp90 and hsp70

    DEFF Research Database (Denmark)

    Chen, S; Prapapanich, V; Rimerman, R A;

    1996-01-01

    mature PR complexes. In the present study we observe that a monoclonal antibody specific for p60 can, on the one hand, inhibit formation of mature PR complexes containing heat shock protein 90 (hsp90), p23, and immunophilins and, on the other, enhance recovery of early PR complexes containing hsp70...

  15. Chlamydia trachomatis and chlamydial heat shock protein 60-specific antibody and cell-mediated responses predict tubal factor infertility

    DEFF Research Database (Denmark)

    Tiitinen, A.; Surcel, H.-M.; Halttunen, M.

    2006-01-01

    BACKGROUND: To evaluate the role of Chlamydia trachomatis-induced humoral and cell-mediated immune (CMI) responses in predicting tubal factor infertility (TFI). METHODS: Blood samples were taken from 88 women with TFI and 163 control women. C. trachomatis and chlamydial heat shock protein 60 (CHSP...

  16. The inactivation of RNase G reduces the Stenotrophomonas maltophilia susceptibility to quinolones by triggering the heat shock response.

    Directory of Open Access Journals (Sweden)

    Alejandra eBernardini

    2015-10-01

    Full Text Available Quinolone resistance is usually due to mutations in the genes encoding bacterial topoisomerases. However different reports have shown that neither clinical quinolone resistant isolates nor in vitro obtained S. maltophilia mutants present mutations in such genes. The mechanisms so far described consist on efflux pumps' overexpression. Our objective is to get information on novel mechanisms of S. maltophilia quinolone resistance. For this purpose, a transposon-insertion mutant library was obtained in S. maltophilia D457.. One mutant presenting reduced susceptibility to nalidixic acid was selected. Inverse PCR showed that the inactivated gene encodes RNase G. Complementation of the mutant with wild-type RNase G allele restored the susceptibility to quinolones. Transcriptomic and real-time RT-PCR analyses showed that several genes encoding heat-shock response proteins were expressed at higher levels in the RNase defective mutant than in the wild-type strain. In agreement with this situation, heat-shock reduces the S. maltophilia susceptibility to quinolone. We can then conclude that the inactivation of the RNase G reduces the susceptibility of S. maltophilia to quinolones, most likely by regulating the expression of heat-shock response genes. Heat-shock induces a transient phenotype of quinolone resistance in S. maltophilia.

  17. Heritable variation in heat shock gene expression: a potential mechanism for adaptation to thermal stress in embryos of sea turtles.

    Science.gov (United States)

    Tedeschi, J N; Kennington, W J; Tomkins, J L; Berry, O; Whiting, S; Meekan, M G; Mitchell, N J

    2016-01-13

    The capacity of species to respond adaptively to warming temperatures will be key to their survival in the Anthropocene. The embryos of egg-laying species such as sea turtles have limited behavioural means for avoiding high nest temperatures, and responses at the physiological level may be critical to coping with predicted global temperature increases. Using the loggerhead sea turtle (Caretta caretta) as a model, we used quantitative PCR to characterise variation in the expression response of heat-shock genes (hsp60, hsp70 and hsp90; molecular chaperones involved in cellular stress response) to an acute non-lethal heat shock. We show significant variation in gene expression at the clutch and population levels for some, but not all hsp genes. Using pedigree information, we estimated heritabilities of the expression response of hsp genes to heat shock and demonstrated both maternal and additive genetic effects. This is the first evidence that the heat-shock response is heritable in sea turtles and operates at the embryonic stage in any reptile. The presence of heritable variation in the expression of key thermotolerance genes is necessary for sea turtles to adapt at a molecular level to warming incubation environments.

  18. Small heat shock proteins inhibit amyloid-beta protein aggregation and cerebrovascular amyloid-beta protein toxicity.

    NARCIS (Netherlands)

    Wilhelmus, M.M.; Boelens, W.C.; Otte-Holler, I.; Kamps, B.; Waal, R.M.W. de; Verbeek, M.M.

    2006-01-01

    Small heat shock proteins Hsp20 and HspB2/B3 co-localize with Abeta deposition in senile plaques and cerebral amyloid angiopathy in Alzheimer's disease brains, respectively. It was the aim of our study to investigate if these and other sHsps bind to wild-type Abeta1-42 or the more toxic Abeta1-40

  19. Comparative physiology and transcriptional networks underlying the heat shock response in Populus trichocarpa, Arabidopsis thaliana and Glycine max

    Energy Technology Data Exchange (ETDEWEB)

    Weston, David [ORNL; Wullschleger, Stan D [ORNL; Yang, Xiaohan [ORNL; Karve, Abhijit A [ORNL; Gunter, Lee E [ORNL; Jawdy, Sara [ORNL; Allen, Sara M [ORNL

    2011-01-01

    The heat shock response continues to be layered with additional complexity as interactions and crosstalk among heat shock proteins (HSPs), the reactive oxygen network and hormonal signalling are discovered. However, comparative analyses exploring variation in each of these processes among species remain relatively unexplored. In controlled environment experiments, photosynthetic response curves were conducted from 22 to 42 C and indicated that temperature optimum of light-saturated photosynthesis was greater for Glycine max relative to Arabidopsis thaliana or Populus trichocarpa. Transcript profiles were taken at defined states along the temperature response curves, and inferred pathway analysis revealed species-specific variation in the abiotic stress and the minor carbohydrate raffinose/galactinol pathways. A weighted gene co-expression network approach was used to group individual genes into network modules linking biochemical measures of the antioxidant system to leaf-level photosynthesis among P. trichocarpa, G. max and A. thaliana. Network-enabled results revealed an expansion in the G. max HSP17 protein family and divergence in the regulation of the antioxidant and heat shock modules relative to P. trichocarpa and A. thaliana. These results indicate that although the heat shock response is highly conserved, there is considerable species-specific variation in its regulation.

  20. PUTATIVE CREATINE KINASE M-ISOFORM IN HUMAN SPERM IS IDENTIFIED AS THE 70-KILODALTON HEAT SHOCK PROTEIN HSPA2

    Science.gov (United States)

    THE PUTATIVE CREATINE KINASE M-ISOFORM IN HUMAN SPERM IS IDENTIFIED AS THE 70 kDa HEAT SHOCK PROTEIN HSPA2* Gabor Huszar1, Kathryn Stone2, David Dix3 and Lynne Vigue11The Sperm Physiology Laboratory, Department of Obstetrics and Gynecology, 2 W.M. Keck Foundatio...

  1. Close correlation between heat shock response and cytotoxicity in Neurospora crassa treated with aliphatic alcohols and phenols

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, U.; Schweim, P.; Fracella, F.; Rensing, L. [Univ. of Bremen (Germany)

    1995-03-01

    In Neurospora crassa the aliphatic alcohols methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, ethylene glycol, glycerol, and allyl alcohol and the phenolic compounds phenol, hydroquinone, resorcinol, pyrogallol, phloroglucinol, sodium salicylate, and acetylsalicylic acid were analyzed with respect to their capacities to induce heat shock proteins (HSP) and to inhibit protein synthesis. Both the alcohols and phenols showed the greatest levels of HSP induction at concentrations which inhibited the overall protein synthesis by about 50%. The abilities of the different alcohols to induce the heat shock response are proportional to their lipophilicities: the lipophilic alcohol isobutanol is maximally inductive at about 0.6 M, whereas the least lipophilic alcohol, methanol, causes maximal induction at 5.7 M. The phenols, in general, show a higher capability to induce the heat shock response. The concentrations for maximal induction range between 25 mM (sodium salicylate) and 100 mM (resorcinol). Glycerol (4.1 M) shifted the concentration necessary for maximal HSP induction by hydroquinone from 50 to 200 mM. The results reveal that the induction of HSP occurs under conditions which considerably constrain cell metabolism. The heat shock response, therefore, does not represent a sensitive marker for toxicity tests but provides a good estimate for the extent of cell damage.

  2. The heat shock response plays an important role in TDP-43 clearance: evidence for dysfunction in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Chen, Han-Jou; Mitchell, Jacqueline C; Novoselov, Sergey; Miller, Jack; Nishimura, Agnes L; Scotter, Emma L; Vance, Caroline A; Cheetham, Michael E; Shaw, Christopher E

    2016-05-01

    Detergent-resistant, ubiquitinated and hyperphosphorylated Tar DNA binding protein 43 (TDP-43, encoded by TARDBP) neuronal cytoplasmic inclusions are the pathological hallmark in ∼95% of amyotrophic lateral sclerosis and ∼60% of frontotemporal lobar degeneration cases. We sought to explore the role for the heat shock response in the clearance of insoluble TDP-43 in a cellular model of disease and to validate our findings in transgenic mice and human amyotrophic lateral sclerosis tissues. The heat shock response is a stress-responsive protective mechanism regulated by the transcription factor heat shock factor 1 (HSF1), which increases the expression of chaperones that refold damaged misfolded proteins or facilitate their degradation. Here we show that manipulation of the heat shock response by expression of dominant active HSF1 results in a dramatic reduction of insoluble and hyperphosphorylated TDP-43 that enhances cell survival, whereas expression of dominant negative HSF1 leads to enhanced TDP-43 aggregation and hyperphosphorylation. To determine which chaperones were mediating TDP-43 clearance we over-expressed a range of heat shock proteins (HSPs) and identified DNAJB2a (encoded by DNAJB2, and also known as HSJ1a) as a potent anti-aggregation chaperone for TDP-43. DNAJB2a has a J domain, allowing it to interact with HSP70, and ubiquitin interacting motifs, which enable it to engage the degradation of its client proteins. Using functionally deleted DNAJB2a constructs we demonstrated that TDP-43 clearance was J domain-dependent and was not affected by ubiquitin interacting motif deletion or proteasome inhibition. This indicates that TDP-43 is maintained in a soluble state by DNAJB2a, leaving the total levels of TDP-43 unchanged. Additionally, we have demonstrated that the levels of HSF1 and heat shock proteins are significantly reduced in affected neuronal tissues from a TDP-43 transgenic mouse model of amyotrophic lateral sclerosis and patients with

  3. Exogenous heat shock cognate protein 70 pretreatment attenuates cardiac and hepatic dysfunction with associated anti-inflammatory responses in experimental septic shock.

    Science.gov (United States)

    Hsu, Jong-Hau; Yang, Rei-Cheng; Lin, Shih-Jen; Liou, Shu-Fen; Dai, Zen-Kong; Yeh, Jwu-Lai; Wu, Jiunn-Ren

    2014-12-01

    It has been recently demonstrated that intracellular heat shock cognate protein 70 (HSC70) can be released into extracellular space with physiologic effects. However, its extracellular function in sepsis is not clear. In this study, we hypothesize that extracellular HSC70 can protect against lipopolysaccharide (LPS)-induced myocardial and hepatic dysfunction because of its anti-inflammatory actions. In Wistar rats, septic shock developed with hypotension, tachycardia, and myocardial and hepatic dysfunction at 4 h following LPS administration (10 mg/kg, i.v.). Pretreatment with recombinant bovine HSC70 (20 μg/kg, i.v.) attenuated LPS-induced hypotension and tachycardia by 21% and 23%, respectively (P shock cognate protein 70 also prevented LPS-induced hypoglycemia (217 vs. 59 mg/dL, P shock, extracellular HSC70 conveys pleiotropic protection on myocardial, hepatic, and systemic derangements, with associated inhibition of proinflammatory mediators including tumor necrosis factor α, nitric oxide, cyclooxygenase 2, and matrix metalloproteinase 9, through mitogen-activated protein kinase/nuclear factor κB signaling pathways. Therefore, extracellular HSC70 may have a promising role in the prophylactic treatment of sepsis.

  4. Similarity Solution for a Cylindrical Shock Wave in a Self-gravitating, Rotating Axisymmetric Dusty Gas with Heat Conduction and Radiation Heat Flux

    Directory of Open Access Journals (Sweden)

    Ruchi Bajargaan

    2017-01-01

    Full Text Available Similarity solutions are obtained for unsteady adiabatic propagation of a cylindrical shock wave in a self gravitating, rotating, axisymmetric dusty gas with heat conduction and radiation heat flux in which variable energy input is continuously supplied by the piston. The dusty gas is taken to be a mixture of non-ideal gas and small solid particles. Azimuthal fluid velocity and axial fluid velocity in the ambient medium are taken to be variable. The equilibrium flow conditions are assumed to be maintained. The initial density is assumed to be constant. The heat conduction is expressed in terms of Fourier’s law and the radiation is taken to be of the diffusion type for an optically thick grey gas model. The thermal conductivity and the absorption coefficient are assumed to vary with temperature and density. The effects of the variation of the gravitational parameter and the heat transfer parameters on the shock strength and the flow variables such as radial velocity, azimuthal velocity, axial velocity, density, pressure, total heat flux, mass behind the shock front, azimuthal vorticity vector, axial vorticity vector, isothermal speed of sound and adiabatic compressibility are studied. It is found that the presence of gravitation effect in the medium modify the radiation and conduction effect on the flow variables.

  5. RhoA Activation Sensitizes Cells to Proteotoxic Stimuli by Abrogating the HSF1-Dependent Heat Shock Response.

    Directory of Open Access Journals (Sweden)

    Roelien A M Meijering

    Full Text Available The heat shock response (HSR is an ancient and highly conserved program of stress-induced gene expression, aimed at reestablishing protein homeostasis to preserve cellular fitness. Cells that fail to activate or maintain this protective response are hypersensitive to proteotoxic stress. The HSR is mediated by the heat shock transcription factor 1 (HSF1, which binds to conserved heat shock elements (HSE in the promoter region of heat shock genes, resulting in the expression of heat shock proteins (HSP. Recently, we observed that hyperactivation of RhoA conditions cardiomyocytes for the cardiac arrhythmia atrial fibrillation. Also, the HSR is annihilated in atrial fibrillation, and induction of HSR mitigates sensitization of cells to this disease. Therefore, we hypothesized active RhoA to suppress the HSR resulting in sensitization of cells for proteotoxic stimuli.Stimulation of RhoA activity significantly suppressed the proteotoxic stress-induced HSR in HL-1 atrial cardiomyocytes as determined with a luciferase reporter construct driven by the HSF1 regulated human HSP70 (HSPA1A promoter and HSP protein expression by Western Blot analysis. Inversely, RhoA inhibition boosted the proteotoxic stress-induced HSR. While active RhoA did not preclude HSF1 nuclear accumulation, phosphorylation, acetylation, or sumoylation, it did impair binding of HSF1 to the hsp genes promoter element HSE. Impaired binding results in suppression of HSP expression and sensitized cells to proteotoxic stress.These results reveal that active RhoA negatively regulates the HSR via attenuation of the HSF1-HSE binding and thus may play a role in sensitizing cells to proteotoxic stimuli.

  6. Suppression of rpoH (htpR) mutations of Escherichia coli: heat shock response in suhA revertants.

    Science.gov (United States)

    Tobe, T; Kusukawa, N; Yura, T

    1987-09-01

    Temperature-resistant pseudorevertants were isolated from rpoH (htpR) mutants of Escherichia coli K-12 that cannot grow at a high temperature owing to a deficiency in sigma 32 required for the induction of heat shock proteins. Among them was a class of revertants carrying a suppressor mutation, designated suhA, that suppressed all the nonsense and missense rpoH mutations tested. suhA is located at 77 min, about 1 min away from rpoH, on the genetic map. In contrast to the rpoH mutants, the suhA revertants that contained both rpoH (nonsense) and suhA mutations were fully or partially proficient in the induction of heat shock proteins upon exposure to a high temperature. Under these conditions, transcription from two heat shock promoters as determined by operon fusion was transiently activated. In one of the rpoH(Am) suhA revertants studied in detail, an increase in temperature caused the synthesis of significant amounts of sigma 32, accompanied by increased stability and accumulation of rpoH mRNAs. On the other hand, the same mutation (suhA6) only weakly suppressed the rpoH deletion mutant; however, two of the major heat shock genes, dnaK and groE, were apparently induced in the absence of sigma 32. Thus, suhA6 seems to bring about the induction of heat shock genes by at least two mechanisms, one increasing the level of sigma 32 synthesis, and the other activating some transcription factor other than sigma 32.

  7. Resveratrol induces antioxidant and heat shock protein mRNA expression in response to heat stress in black-boned chickens.

    Science.gov (United States)

    Liu, L L; He, J H; Xie, H B; Yang, Y S; Li, J C; Zou, Y

    2014-01-01

    This study investigated the effects of dietary resveratrol at 0, 200, 400, or 600 mg/kg of diet on the performance, immune organ growth index, serum parameters, and expression levels of heat shock protein (Hsp) 27, Hsp70, and Hsp90 mRNA in the bursa of Fabricius, thymus, and spleen of 42-d-old female black-boned chickens exposed to heat stress at 37 ± 2°C for 15 d. The results showed that heat stress reduced daily feed intake and BW gain; decreased serum glutathione (GSH), growth hormone, and insulin-like growth factor-1 levels; and inhibited GSH peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT) activities compared with birds subjected to thermo-neutral circumstances. Chickens that were fed diets supplemented with resveratrol exhibited a linear increase in feed intake and BW gain (P chickens that were fed diets without resveratrol during heat stress. In contrast, serum malonaldehyde concentrations were decreased (P chickens fed a resveratrol-supplemented diet. Heat stress also reduced (P heat stress and coincided with an increase in supplemental resveratrol levels. The expression of Hsp27, Hsp70, and Hsp90 mRNA in the bursa of Fabricius and spleen were increased (P heat stress compared with no heat stress. Resveratrol attenuated the heat stress-induced overexpression of Hsp27, Hsp70, and Hsp90 mRNA in the bursa of Fabricius and spleen and increased the low expression of Hsp27 and Hsp90 mRNA in thymus upon heat stress. The results suggest that supplemental resveratrol improves growth performance and reduces oxidative stress in heat-stressed black-boned chickens by increasing serum growth hormone concentrations and modulating the expression of heat shock genes in organs of the immune system.

  8. Quercetin suppresses heat shock-induced nuclear translocation of Hsp72

    Directory of Open Access Journals (Sweden)

    Antoni Gawron

    2011-08-01

    Full Text Available The effect of quercetin and heat shock on the Hsp72 level and distribution in HeLa cells was studied by Western blotting, indirect immunofluorescence and immunogold electron microscopy. In control cells and after quercetin treatment, Hsp72 was located both in the cytoplasm and in the nucleus in comparable amounts. After hyperthermia, the level of nuclear Hsp72 raised dramatically. Expression of Hsp72 in cytoplasm was also higher but not to such extent as that observed in the nucleus. Preincubation of heated cells with quercetin inhibited strong Hsp72 expression observed after hyperthermia and changed the intracellular Hsp72 distribution. The cytoplasmic level of protein exceeded the nuclear one, especially around the nucleus, where the coat of Hsp72 was noticed. Observations indicating that quercetin was present around and in the nuclear envelope suggested an involvement of this drug in the inhibition of nuclear translocation. Our results indicate that pro-apoptotic activity of quercetin may be correlated not only with the inhibition of Hsp72 expression but also with suppression of its migration to the nucleus.

  9. Functional differentiation of small heat shock proteins in diapause-destined Artemia embryos.

    Science.gov (United States)

    King, Allison M; Toxopeus, Jantina; MacRae, Thomas H

    2013-10-01

    Encysted embryos of Artemia franciscana cease development and enter diapause, a state of metabolic suppression and enhanced stress tolerance. The development of diapause-destined Artemia embryos is characterized by the coordinated synthesis of the small heat shock proteins (sHsps) p26, ArHsp21 and ArHsp22, with the latter being stress inducible in adults. The amounts of sHsp mRNA and protein varied in Artemia cysts, suggesting transcriptional and translational regulation. By contrast to p26, knockdown of ArHsp21 by RNA interference had no effect on embryo development. ArHsp21 provided limited protection against stressors such as desiccation and freezing but not heat. ArHsp21 may have a non-essential or unidentified role in cysts. Injection of Artemia adults with amounts of ArHsp22 double-stranded RNA less than those used for other sHsps killed females and males, curtailing the analysis of ArHsp22 function in developing embryos and cysts. The results indicate that diapause-destined Artemia embryos synthesize varying amounts of sHsps as a result of differential gene expression and mRNA translation and also suggest that these sHsps have distinctive functions.

  10. Expression of Heat Shock Proteins in Human Fibroblast Cells under Magnetic Resonant Coupling Wireless Power Transfer

    Directory of Open Access Journals (Sweden)

    Kohei Mizuno

    2015-10-01

    Full Text Available Since 2007, resonant coupling wireless power transfer (WPT technology has been attracting attention and has been widely researched for practical use. Moreover, dosimetric evaluation has also been discussed to evaluate the potential health risks of the electromagnetic field from this WPT technology based on the International Commission on Non-Ionizing Radiation Protection (ICNIRP guidelines. However, there has not been much experimental evaluation of the potential health risks of this WPT technology. In this study, to evaluate whether magnetic resonant coupling WPT induces cellular stress, we focused on heat shock proteins (Hsps and determined the expression level of Hsps 27, 70 and 90 in WI38VA13 subcloned 2RA human fibroblast cells using a western blotting method. The expression level of Hsps under conditions of magnetic resonant coupling WPT for 24 h was not significantly different compared with control cells, although the expression level of Hsps for cells exposed to heat stress conditions was significantly increased. These results suggested that exposure to magnetic resonant coupling WPT did not cause detectable cell stress.

  11. Investigating the Chaperone Properties of a Novel Heat Shock Protein, Hsp70.c, from Trypanosoma brucei

    Directory of Open Access Journals (Sweden)

    Adélle Burger

    2014-01-01

    Full Text Available The neglected tropical disease, African Trypanosomiasis, is fatal and has a crippling impact on economic development. Heat shock protein 70 (Hsp70 is an important molecular chaperone that is expressed in response to stress and Hsp40 acts as its co-chaperone. These proteins play a wide range of roles in the cell and they are required to assist the parasite as it moves from a cold blooded insect vector to a warm blooded mammalian host. A novel cytosolic Hsp70, from Trypanosoma brucei, TbHsp70.c, contains an acidic substrate binding domain and lacks the C-terminal EEVD motif. The ability of a cytosolic Hsp40 from Trypanosoma brucei J protein 2, Tbj2, to function as a co-chaperone of TbHsp70.c was investigated. The main objective was to functionally characterize TbHsp70.c to further expand our knowledge of parasite biology. TbHsp70.c and Tbj2 were heterologously expressed and purified and both proteins displayed the ability to suppress aggregation of thermolabile MDH and chemically denatured rhodanese. ATPase assays revealed a 2.8-fold stimulation of the ATPase activity of TbHsp70.c by Tbj2. TbHsp70.c and Tbj2 both demonstrated chaperone activity and Tbj2 functions as a co-chaperone of TbHsp70.c. In vivo heat stress experiments indicated upregulation of the expression levels of TbHsp70.c.

  12. Overexpression of small heat shock protein LimHSP16.45 in Arabidopsis enhances tolerance to abiotic stresses.

    Directory of Open Access Journals (Sweden)

    Changjun Mu

    Full Text Available Small heat shock proteins (smHSPs play important and extensive roles in plant defenses against abiotic stresses. We cloned a gene for a smHSP from the David Lily (Lilium davidii (E. H. Wilson Raffill var. Willmottiae, which we named LimHSP16.45 based on its protein molecular weight. Its expression was induced by many kinds of abiotic stresses in both the lily and transgenic plants of Arabidopsis. Heterologous expression enhanced cell viability of the latter under high temperatures, high salt, and oxidative stress, and heat shock granules (HSGs formed under heat or salinity treatment. Assays of enzymes showed that LimHSP16.45 overexpression was related to greater activity by superoxide dismutase and catalase in transgenic lines. Therefore, we conclude that heterologous expression can protect plants against abiotic stresses by preventing irreversible protein aggregation, and by scavenging cellular reactive oxygen species.

  13. Effect of the C.-1 388 A>G polymorphism in chicken heat shock transcription factor 3 gene on heat tolerance

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wen-wu; KONG Li-na; ZHANG De-xiang; JI Cong-liang; ZHANG Xi-quan; LUO Qing-bin

    2015-01-01

    Heat stress is one of the main factors that inlfuence poultry production. Heat shock proteins (HSPs) are known to affect heat tolerance. The formation of HSPs is regulated by heat shock transcription factor 3 (HSF3) in chicken. A DNA pool was established for identifying single nucleotide polymorphisms (SNPs) of the chicken HSF3, and 13 SNPs were detected. The bioinformatic analysis showed that 8 SNPs had the capacity to alter the transcription activity of HSF3. The dual luciferase report gene assay showed that there was a signiifcant difference (PG (S1) and C.–1 388 A>G (S4) sites at the 5´-untranslated region (UTR) of chicken HSF3. The elec-trophoretic mobility shift assay showed that the S4 site was a transcription binding factor. The analysis of the association of the S1 and S4 sites with heat tolerance index revealed that the S4 site was signiifcantly correlated with the CD3+T cel , corticosterone, and T3 levels in Lingshan chickens and with the heterophil/lymphocyte value in White Recessive Rock. These results showed that the S4 site at the 5´ UTR of chicken HSF3 might have an impact on heat tolerance in summer and could be used as a potential marker for the selection of chicken with heat tolerance in the future.

  14. Gas-dynamic shock heating of post-flare loops due to retraction following localized, impulsive reconnection

    CERN Document Server

    Longcope, D W; Linton, M G

    2008-01-01

    We present a novel model in which shortening of a magnetic flux tube following localized, three-dimensional reconnection generates strong gas-dynamic shocks around its apex. The shortening releases magnetic energy by progressing away from the reconnection site at the Alfven speed. This launches inward flows along the field lines whose collision creates a pair of gas-dynamic shocks. The shocks raise both the mass density and temperature inside the newly shortened flux tube. Reconnecting field lines whose initial directions differ by more that 100 degrees can produce a concentrated knot of plasma hotter that 20 MK, consistent with observations. In spite of these high temperatures, the shocks convert less than 10% of the liberated magnetic energy into heat - the rest remains as kinetic energy of bulk motion. These gas-dynamic shocks arise only when the reconnection is impulsive and localized in all three dimensions; they are distinct from the slow magnetosonic shocks of the Petschek steady-state reconnection mod...

  15. Short-term heat shock affects the course of immune response in Galleria mellonella naturally infected with the entomopathogenic fungus Beauveria bassiana.

    Science.gov (United States)

    Vertyporokh, Lidiia; Taszłow, Paulina; Samorek-Pieróg, Małgorzata; Wojda, Iwona

    2015-09-01

    We aimed to investigate how exposition of infected insects to short-term heat shock affects the biochemical and molecular aspects of their immune response. Galleria mellonella larvae were exposed to 43°C for 15min, at the seventy second hour after natural infection with entomopathogenic fungus Beauveria bassiana. As a result, both qualitative and quantitative changes in hemolymph protein profiles, and among them infection-induced changes in the amount of apolipophorin III (apoLp-III), were observed. Heat shock differently affects the expression of the tested immune-related genes. It transiently inhibits expression of antifungal peptides gallerimycin and galiomicin in both the fat body and hemocytes of infected larvae. The same, although to a lesser extent, concerned apoLp-III gene expression and was observed directly after heat shock. Nevertheless, in larvae that had recovered from heat shock, apoLp-III expression was higher in comparison to unshocked larvae in the fat body but not in hemocytes, which was consistent with the higher amount of this protein detected in the hemolymph of the infected, shocked larvae. Furthermore, lysozyme-type activity was higher directly after heat shock, while antifungal activity was significantly higher also in larvae that had recovered from heat shock, in comparison to the respective values in their non-shocked, infected counterparts. These results show how changes in the external temperature modulate the immune response of G. mellonella suffering from infection with its natural pathogen B. bassiana.

  16. Coronal Heating and Acceleration of the High/Low-Speed Solar Wind by Fast/Slow MHD Shock Trains

    CERN Document Server

    Suzuki, T K

    2004-01-01

    We investigate coronal heating and acceleration of the high- and low-speed solar wind in the open field region by dissipation of fast and slow magnetohydrodynamical (MHD) waves through MHD shocks. Linearly polarized \\Alfven (fast MHD) waves and acoustic (slow MHD) waves travelling upwardly along with a magnetic field line eventually form fast switch-on shock trains and hydrodynamical shock trains (N-waves) respectively to heat and accelerate the plasma. We determine one dimensional structure of the corona from the bottom of the transition region (TR) to 1AU under the steady-state condition by solving evolutionary equations for the shock amplitudes simultaneously with the momentum and proton/electron energy equations. Our model reproduces the overall trend of the high-speed wind from the polar holes and the low-speed wind from the mid- to low-latitude streamer except the observed hot corona in the streamer. The heating from the slow waves is effective in the low corona to increase the density there, and plays ...

  17. MIPS: a calmodulin-binding protein of Gracilaria lemaneiformis under heat shock.

    Science.gov (United States)

    Zhang, Xuan; Zhou, Huiyue; Zang, Xiaonan; Gong, Le; Sun, Hengyi; Zhang, Xuecheng

    2014-08-01

    To study the Ca(2+)/Calmodulin (CaM) signal transduction pathway of Gracilaria lemaneiformis under heat stress, myo-inositol-1-phosphate synthase (MIPS), a calmodulin-binding protein, was isolated using the yeast two-hybrid system. cDNA and DNA sequences of mips were cloned from G. lemaneiformis by using 5'RACE and genome walking procedures. The MIPS DNA sequence was 2,067 nucleotides long, containing an open reading frame (ORF) of 1,623 nucleotides with no intron. The mips ORF was predicted to encode 540 amino acids, which included the conserved MIPS domain and was 61-67 % similar to that of other species. After analyzing the amino acid sequence of MIPS, the CaM-Binding Domain (CaMBD) was inferred to be at a site spanning from amino acid 212 to amino acid 236. The yeast two-hybrid results proved that MIPS can interact with CaM and that MIPS is a type of calmodulin-binding protein. Next, the expression of CaM and MIPS in wild-type G. lemaneiformis and a heat-tolerant G. lemaneiformis cultivar, "981," were analyzed using real-time PCR under a heat shock of 32 °C. The expression level displayed a cyclical upward trend. Compared with wild type, the CaM expression levels of cultivar 981 were higher, which might directly relate to its resistance to high temperatures. This paper indicates that MIPS and CaM may play important roles in the high-temperature resistance of G. lemaneiformis.

  18. Involvement of small heat shock proteins, trehalose, and lipids in the thermal stress management in Schizosaccharomyces pombe.

    Science.gov (United States)

    Glatz, Attila; Pilbat, Ana-Maria; Németh, Gergely L; Vince-Kontár, Katalin; Jósvay, Katalin; Hunya, Ákos; Udvardy, Andor; Gombos, Imre; Péter, Mária; Balogh, Gábor; Horváth, Ibolya; Vígh, László; Török, Zsolt

    2016-03-01

    Changes in the levels of three structurally and functionally different important thermoprotectant molecules, namely small heat shock proteins (sHsps), trehalose, and lipids, have been investigated upon heat shock in Schizosaccharomyces pombe. Both α-crystallin-type sHsps (Hsp15.8 and Hsp16) were induced after prolonged high-temperature treatment but with different kinetic profiles. The shsp null mutants display a weak, but significant, heat sensitivity indicating their importance in the thermal stress management. The heat induction of sHsps is different in wild type and in highly heat-sensitive trehalose-deficient (tps1Δ) cells; however, trehalose level did not show significant alteration in shsp mutants. The altered timing of trehalose accumulation and induction of sHsps suggest that the disaccharide might provide protection at the early stage of the heat stress while elevated amount of sHsps are required at the later phase. The cellular lipid compositions of two different temperature-adapted wild-type S. pombe cells are also altered according to the rule of homeoviscous adaptation, indicating their crucial role in adapting to the environmental temperature changes. Both Hsp15.8 and Hsp16 are able to bind to different lipids isolated from S. pombe, whose interaction might provide a powerful protection against heat-induced damages of the membranes. Our data suggest that all the three investigated thermoprotectant macromolecules play a pivotal role during the thermal stress management in the fission yeast.

  19. Antitumor immunity induced by DNA vaccine encoding alpha-fetoprotein/heat shock protein 70

    Institute of Scientific and Technical Information of China (English)

    Xiao-Ping Wang; Guo-Zhen Liu; Ai-Li Song; Hai-Yan Li; Yu Liu

    2004-01-01

    AIM: To construct a DNA vaccine encoding human alphafetoprotein (hAFP)/heat shock protein 70 (HSP70), and to study its ability to induce specific CTL response and its protective effect against AFP-expressing tumor.METHODS: A DNA vaccine was constructed by combining hAFP gene with HSP70 gene. SP2/0 cells were stably transfected with pBBS212-hAFP and pBBS212-hAFP/HSP70eukaryotic expression vectors. Mice were primed and boosted with DNA vaccine hAFP/HSP70 by intramuscular injection, whereas plasmid with hAFP or HSP70 was used as controls. ELISPOT and ELISA were used to detect IFN-γ-producing splenocytes and the level of serum anti-AFP antibody from immunized mice respectively. In vivo tumor challenge was measured to assess the immune effect of the DNA vaccine.RESULTS: By DNA vaccine immunization, the results of ELISPOT and ELISA showed that the number of IFN-γ-producing splenocytes and the level of serum anti-AFP antibody were significantly higher in rhAFP/HSP70 group than in hAFP and empty plasmid groups (95.50±10.90IFN-γ spots/106 cells vs 23.60±11.80 IFN-γ spots/106 cells,7.17±4.24 IFN-γ spots/106 cells, P<0.01; 126.50±8.22 μg/mL vs 51.72±3.40 μg/mL, 5.83±3.79 μg/mL, P<0.01). The tumor volume in rhAFP/HSP70 group was significantly smaller than that in pBBS212-hAFP and empty plasmid groups (37.41±7.34 mm3 vs381.13±15.48 mm3, 817.51±16.25 mm3,P<0.01).CONCLUSION: Sequential immunization with a recombinant DNA vaccine encoding AFP and heat shock protein70 could generate effective AFP-specific T cell responses and induce definite antitumor effects on AFP-producing tumors, which may be suitable for some clinical testing as a vaccine for HCC.

  20. Inhibiting heat-shock protein 90 reverses sensory hypoalgesia in diabetic mice

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    Brian S J Blagg

    2010-08-01

    Full Text Available Increasing the expression of Hsp70 (heat-shock protein 70 can inhibit sensory neuron degeneration after axotomy. Since the onset of DPN (diabetic peripheral neuropathy is associated with the gradual decline of sensory neuron function, we evaluated whether increasing Hsp70 was sufficient to improve several indices of neuronal function. Hsp90 is the master regulator of the heat-shock response and its inhibition can up-regulate Hsp70. KU-32 (N-{7-[(2R,3R,4S,5R-3,4-dihydroxy-5-methoxy-6,6-dimethyl-tetrahydro-2H-pyran-2-yloxy]-8-methyl-2-oxo-2H-chromen-3-yl}acetamide was developed as a novel, novobiocin-based, C-terminal inhibitor of Hsp90 whose ability to increase Hsp70 expression is linked to the presence of an acetamide substitution of the prenylated benzamide moiety of novobiocin. KU-32 protected against glucose-induced death of embryonic DRG (dorsal root ganglia neurons cultured for 3 days in vitro. Similarly, KU-32 significantly decreased neuregulin 1-induced degeneration of myelinated Schwann cell DRG neuron co-cultures prepared from WT (wild-type mice. This protection was lost if the co-cultures were prepared from Hsp70.1 and Hsp70.3 KO (knockout mice. KU-32 is readily bioavailable and was administered once a week for 6 weeks at a dose of 20 mg/kg to WT and Hsp70 KO mice that had been rendered diabetic with streptozotocin for 12 weeks. After 12 weeks of diabetes, both WT and Hsp70 KO mice developed deficits in NCV (nerve conduction velocity and a sensory hypoalgesia. Although KU-32 did not improve glucose levels, HbA1c (glycated haemoglobin or insulin levels, it reversed the NCV and sensory deficits in WT but not Hsp70 KO mice. These studies provide the first evidence that targeting molecular chaperones reverses the sensory hypoalgesia associated with DPN.

  1. Inhibiting heat-shock protein 90 reverses sensory hypoalgesia in diabetic mice.

    Science.gov (United States)

    Urban, Michael J; Li, Chengyuan; Yu, Cuijuan; Lu, Yuanming; Krise, Joanna M; McIntosh, Michelle P; Rajewski, Roger A; Blagg, Brian S J; Dobrowsky, Rick T

    2010-08-11

    Increasing the expression of Hsp70 (heat-shock protein 70) can inhibit sensory neuron degeneration after axotomy. Since the onset of DPN (diabetic peripheral neuropathy) is associated with the gradual decline of sensory neuron function, we evaluated whether increasing Hsp70 was sufficient to improve several indices of neuronal function. Hsp90 is the master regulator of the heat-shock response and its inhibition can up-regulate Hsp70. KU-32 (N-{7-[(2R,3R,4S,5R)-3,4-dihydroxy-5-methoxy-6,6-dimethyl-tetrahydro-2H-pyran-2-yloxy]-8-methyl-2-oxo-2H-chromen-3-yl}acetamide) was developed as a novel, novobiocin-based, C-terminal inhibitor of Hsp90 whose ability to increase Hsp70 expression is linked to the presence of an acetamide substitution of the prenylated benzamide moiety of novobiocin. KU-32 protected against glucose-induced death of embryonic DRG (dorsal root ganglia) neurons cultured for 3 days in vitro. Similarly, KU-32 significantly decreased neuregulin 1-induced degeneration of myelinated Schwann cell DRG neuron co-cultures prepared from WT (wild-type) mice. This protection was lost if the co-cultures were prepared from Hsp70.1 and Hsp70.3 KO (knockout) mice. KU-32 is readily bioavailable and was administered once a week for 6 weeks at a dose of 20 mg/kg to WT and Hsp70 KO mice that had been rendered diabetic with streptozotocin for 12 weeks. After 12 weeks of diabetes, both WT and Hsp70 KO mice developed deficits in NCV (nerve conduction velocity) and a sensory hypoalgesia. Although KU-32 did not improve glucose levels, HbA1c (glycated haemoglobin) or insulin levels, it reversed the NCV and sensory deficits in WT but not Hsp70 KO mice. These studies provide the first evidence that targeting molecular chaperones reverses the sensory hypoalgesia associated with DPN.

  2. Anopheles gambiae heat shock protein cognate 70B impedes o'nyong-nyong virus replication

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    Higgs Stephen

    2007-07-01

    Full Text Available Abstract Background Phylogenetic and functional analysis was conducted on an Anopheles gambiae gene, ENSANGG00000017398. Based on phylogenetic analysis, this gene belongs to the same lineage as Heat shock protein cognate 70-4 (Hsc70-4 in Drosophila. Accordingly, we propose to name this gene Heat shock protein cognate 70B (HSC70B. We previously reported that expression of HSC70B and other genes including elongation factor-1α (EF-1α and the agglutinin attachment subunit (agglutinin were up-regulated in o'nyong-nyong virus (ONNV-infected female An. gambiae. Double-stranded RNA interferences have been applied to further investigate HSC70B, EF-1α and the agglutinin functions in ONNV replication in An. gambiae. Results Among these three RNAi silenced genes, only dsRNAs of HSC70B (dsHSC70B promoted ONNV replication in adult An. gambiae compared to the control mosquitoes that were co-injected with ONNV and dsRNA of β-galactosidase (dsβ-gal. ONNV titers from mosquitoes co-injected with dsHSC70B were about 9-fold higher at 6 days post-injection (d.p.i. as compared to the control mosquitoes. By using ONNV tagged with enhanced green fluorescent protein (ONNV-eGFP, co-injection of ONNV-eGFP with dsHSC70B also showed approximately 2 ~ 3-fold higher GFP expression rates than the controls in the head, thorax, and abdomen of the mosquito. Furthermore, co-injection of ONNV with dsHSC70B significantly reduced the lifespan of adult mosquitoes as compared with the control, co-injection of ONNV with dsβ-gal treated mosquitoes. Conclusion These results indicate that HSC70B plays important roles in homeostasis and suppression of ONNV replication in the vector, An. gambiae. Biological implications of these findings are that while mosquitoes allow ONNV to replicate in them, they also check viral titers so that ONNV infection will result in no harmful effect on mosquitoes. Therefore, mosquitoes can function as vectors of ONNV transmission to humans while ONNV

  3. Heat shock protein 90 has roles in intracellular calcium homeostasis, protein tyrosine phosphorylation regulation, and progesterone-responsive sperm function in human sperm.

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    Kun Li

    Full Text Available Heat shock protein 90 plays critical roles in client protein maturation, signal transduction, protein folding and degradation, and morphological evolution; however, its function in human sperm is not fully understood. Therefore, our objective in this study was to elucidate the mechanism by which heat shock protein 90 exerts its effects on human sperm function. By performing indirect immunofluorescence staining, we found that heat shock protein 90 was localized primarily in the neck, midpiece, and tail regions of human sperm, and that its expression increased with increasing incubation time under capacitation conditions. Geldanamycin, a specific inhibitor of heat shock protein 90, was shown to inhibit this increase in heat shock protein 90 expression in western blotting analyses. Using a multifunctional microplate reader to examine Fluo-3 AM-loaded sperm, we observed for the first time that inhibition of heat shock protein 90 by using geldanamycin significantly decreased intracellular calcium concentrations during capacitation. Moreover, western blot analysis showed that geldanamycin enhanced tyrosine phosphorylation of several proteins, including heat shock protein 90, in a dose-dependent manner. The effects of geldanamycin on human sperm function in the absence or presence of progesterone was evaluated by performing chlortetracycline staining and by using a computer-assisted sperm analyzer. We found that geldanamycin alone did not affect sperm capacitation, hyperactivation, and motility, but did so in the presence of progesterone. Taken together, these data suggest that heat shock protein 90, which increases in expression in human sperm during capacitation, has roles in intracellular calcium homeostasis, protein tyrosine phosphorylation regulation, and progesterone-stimulated sperm function. In this study, we provide new insights into the roles of heat shock protein 90 in sperm function.

  4. Effects of chronic heat stress on the expressions of heat shock proteins 60, 70, 90, A2, and HSC70 in the rabbit testis.

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    Pei, Yangli; Wu, Yingjie; Qin, Yinghe

    2012-01-01

    Few studies have focused on the expression of heat shock proteins (HSPs) after chronic heat stress. The objective of this study was to investigate the effect of chronic high temperature-humidity index treatment on the expressions of HSP60, HSP70, HSP90, HSPA2 and HSC70, in the Rex rabbit testis and the expressions of these proteins after recovery from the chronic heat shock. Thirty mature male rabbits of the same age were randomly divided into three groups: control, heat stress, and recovery. The western blot results showed that the expressional levels of HSP60, HSP90, and HSC70 increased significantly and HSPA2 was elevated slightly after a 9-week heat treatment. HSP70 was absent in the control testis and had a high level of expression after heat stress. All of these proteins partially reverted back to normal levels after a 9-week recovery. The immunohistochemical results indicated that the expression patterns of HSP60, HSP90, HSPA2, and HSC70 did not change.

  5. Nonlinear interactions in superfluid dynamics: Nonstationary heat transfer due to second sound shock waves

    Science.gov (United States)

    Liepmann, H. W.; Torczynski, J. R.

    1983-01-01

    Second sound techniques were used to study superfluid helium. Second sound shock waves produced relative velocities in the bulk fluid. Maximum counterflow velocities produced in this way are found to follow the Langer-Fischer prediction for the fundamental critical velocity in its functional dependence on temperature and pressure. Comparison of successive shock and rotating experiments provides strong evidence that breakdown results in vorticity production in the flow behind the shock. Schlieren pictures have verified the planar nature of second sound shocks even after multiple reflections. The nonlinear theory of second sound was repeatedly verified in its prediction of double shocks and other nonlinear phenomena.

  6. Investigations on biological functions of heat shock transcription factor 1 (HSF1) using a gene knock out mouse model

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    HSF1 is the major heat shock transcription factor that binds heat shock element (HSE) in the promoter of heat shock proteins (HSPs) and controls rapid HSP induction in cells subjected to various stresses such as elevated temperature, chemicals, or exposure to toxins. Although at least four members of the vertebrate HSF have been cloned, details of their individual physiological roles remain relatively obscure. To clarify the exact in vivo functions of HSF1 and assess whether HSF1 exhibits redundant or unique roles, we have created homozygous Hsf1-/- mice using standard gene targeting techniques and isolated Hsf1-/- embryonic fibroblasts. Here we demonstrate that heat shock response (HSR) was not attainable in Hsf1-/- embryonic fibroblasts, and this response was required for thermotolerance and protection against heat-induced apoptosis, and that homozygous Hsf1-/- mice, which survived to adulthood according to genetic background, exhibited multiple phenotypes including: (1) placental defects that reduced embryonic viability after late midgestation (day 13.5); (2) growth retardation; (3) female infertility caused by preimplantation lethality, and (4) increased mortality (+/+ vs -/-, P<0.05) and exaggerated production of proinflammatory cytokine, TNF α (+/- vs -/-, P<0.05) after endotoxin challenge. Interestingly, although Hsf1-/- mice exhibited placental defects and embryonic death, basal HSP expression is not appreciably altered during embryonic development by the HSF1 null mutation, suggesting this factor might be involved in regulating some non-HSP genes or signaling pathways which may be important for development. Taken together, our results established direct causal effects for the HSF1 transactivator in regulating diverse physiological and pathophysiological conditions such as developnent, growth, reproduction, apoptosis and sepsis. The present work also provided a useful mammalian model for further investigating the implications of Hsf1 and its target

  7. The 70 kDa heat shock protein assists during the repair of chilling injury in the insect, Pyrrhocoris apterus.

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    Vladimír Kostál

    Full Text Available BACKGROUND: The Pyrrhocoris apterus (Insecta: Heteroptera adults attain high levels of cold tolerance during their overwintering diapause. Non-diapause reproducing adults, however, lack the capacity to express a whole array of cold-tolerance adaptations and show relatively low survival when exposed to sub-zero temperatures. We assessed the competence of non-diapause males of P. apterus for responding to heat- and cold-stresses by up-regulation of 70 kDa heat shock proteins (Hsps and the role of Hsps during repair of heat- and cold-induced injury. PRINCIPAL FINDINGS: The fragments of P. apterus homologues of Hsp70 inducible (PaHsp70 and cognate forms (PaHsc70 were cloned and sequenced. The abundance of mRNA transcripts for the inducible form (qPCR and corresponding protein (Western blotting were significantly up-regulated in response to high and low temperature stimuli. In the cognate form, mRNA was slightly up-regulated in response to both stressors but very low or no up-regulation of protein was apparent after heat- or cold-stress, respectively. Injection of 695 bp-long Pahsp70 dsRNA (RNAi caused drastic suppression of the heat- and cold-stress-induced Pahsp70 mRNA response and the up-regulation of corresponding protein was practically eliminated. Our RNAi predictably prevented recovery from heat shock and, in addition, negatively influenced repair of chilling injuries caused by cold stress. Cold tolerance increased when the insects were first exposed to a mild heat shock, in order to trigger the up-regulation of PaHsp70, and subsequently exposed to cold stress. CONCLUSION: Our results suggest that accumulation of PaHsp70 belongs to a complex cold tolerance adaptation in the insect Pyrrhocoris apterus.

  8. Heat Shock-Induced Three-Dimensional-Like Proliferation of Normal Human Fibroblasts Mediated by Pressed Silk

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    Shigeki Inoue

    2009-11-01

    Full Text Available The aim of this study was to determine the optimal heat treatment conditions for enhancement of pressed silk-mediated 3D-like proliferation of normal human dermal fibroblasts, as well as to determine the responses to heat shock of cells and intracellular signaling pathways. The beginning of 3D-like pattern formation of cells was observed in the second week after the start of the experiment. The mean rates of beginning of 3D-like pattern formation by cells heat-treated at 40 ºC and 43 ºC for 10 min were significantly higher (3.2- and 8.6-fold, respectively than that of untreated cells. We found that apoptosis had occurred in 7.5% and 50.0% of the cells at one week after heat treatment for 10 min at 43 ºC and 45 ºC, respectively. Western blot analysis demonstrated that phosphorylation of p38 MAPK and that of Hsp27 were markedly increased by heat treatment at 43 ºC for 10 min. The results of an experiment using a p38 MAPK inhibitor and Hsp27 inhibitor suggest that activation of p38 MAPK by heat shock is associated with 3D-like cell proliferation and that Hsp27 contributes to the inhibition of apoptosis. The results of this study should be useful for further studies aimed at elucidation of the physiologic mechanisms underlying thermotherapy.

  9. Structure of the Contact Region and its Application to the Reflexion of a Plane Shock Wave from a Heat Conducting Wall

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    B. C. Pandey

    1970-07-01

    Full Text Available A study of the structure of the contact region has been made taking into account the effects of viscosity, heat conduction and radiative heat transfer. Analytical solutions for the temperature, velocity and pressure distributions in a uniformly moving contact region have been obtained under the optically thick-gas approximation when the thermal conductivity and absorption coefficients are given by power laws. Applying the analysis of the contact region to the situation when a plane shock is reflected from a plane heat-conducting wall it has been shown that the reflected shock is attenuated due to the combined effects of molecular heat conduction and radiative heat conduction.

  10. Transcriptional regulation of heat shock proteins and ascorbate peroxidase by CtHsfA2b from African bermudagrass conferring heat tolerance in Arabidopsis

    Science.gov (United States)

    Wang, Xiuyun; Huang, Wanlu; Yang, Zhimin; Liu, Jun; Huang, Bingru

    2016-01-01

    Heat stress transcription factor A2s (HsfA2s) are key regulators in plant response to high temperature. Our objectives were to isolate an HsfA2 gene (CtHsfA2b) from a warm-season grass species, African bermudagrass (Cynodon transvaalensis Burtt-Davy), and to determine the physiological functions and transcriptional regulation of HsfA2 for improving heat tolerance. Gene expression analysis revealed that CtHsfA2b was heat-inducible and exhibited rapid response to increasing temperature. Ectopic expression of CtHsfA2b improved heat tolerance in Arabidopsis and restored heat-sensitive defects of Arabidopsis hsfa2 mutant, which was demonstrated by higher survival rate and photosynthetic parameters, and lower electrolyte leakage in transgenic plants compared to the WT or hsfa2 mutant. CtHsfA2b transgenic plants showed elevated transcriptional regulation of several downstream genes, including those encoding ascorbate peroxidase (AtApx2) and heat shock proteins [AtHsp18.1-CI, AtHsp22.0-ER, AtHsp25.3-P and AtHsp26.5-P(r), AtHsp70b and AtHsp101-3]. CtHsfA2b was found to bind to the heat shock element (HSE) on the promoter of AtApx2 and enhanced transcriptional activity of AtApx2. These results suggested that CtHsfA2b could play positive roles in heat protection by up-regulating antioxidant defense and chaperoning mechanisms. CtHsfA2b has the potential to be used as a candidate gene to genetically modify cool-season species for improving heat tolerance. PMID:27320381

  11. [Some properties of complexes formed by small heat shock proteins with denatured actin].

    Science.gov (United States)

    Pivovarova, A V; Chebotareva, N A; Guseev, N B; Levitskiĭ, D I

    2008-01-01

    We applied different methods to analyze the effects of the recombinant wild-type small heat shock protein with an apparent molecular mass of 27 kD (Hsp27-wt) and its S15,78,82D mutant (Hsp27-3D), which mimics the naturally occurring phosphorylation of this protein, on the thermal denaturation and aggregation of F-actin. It has been shown that, at the weight ratio of Hsp27/actin equal to 1/4, both Hsp27-wt and Hsp27-3D do not affect the thermal unfolding of F-actin but effectively prevent the aggregation of F-actin by forming soluble complexes with denatured actin. The formation of these complexes occurs upon heating and accompanies the F-actin thermal denaturation. It is known that Hsp27-wt forms high-molecular-mass oligomers, whereas Hsp27-3D forms small dimers or tetramers. However, the complexes formed by Hsp27-wt and Hsp27-3D with denatured actin did not differ in their size, as measured by dynamic light scattering, and demonstrated the same hydrodynamic radius of 17-18 nm. On the other hand, the sedimentation coefficients of these complexes were distributed within the range 10-45 S in the case of Hsp27-3D and 18-60 S in the case of Hsp27-wt. Thus, the ability of Hsp27 to form soluble complexes with denatured actin does not significantly depend on the initial oligomeric state of Hsp27.

  12. Small heat shock proteins and the postharvest chilling tolerance of tomato fruit.

    Science.gov (United States)

    Ré, Martín D; Gonzalez, Carla; Escobar, Mariela R; Sossi, María Laura; Valle, Estela M; Boggio, Silvana B

    2017-02-01

    Plants have the largest number of small heat shock proteins (sHsps) (15-42 kDa) among eukaryotes, but little is known about their function in vivo. They accumulate in response to different stresses, and specific sHsps are also expressed during developmental processes such as seed development, germination, and ripening. The presence of organelle-specific sHsps appears to be unique to plants. The sHsps expression is regulated by heat stress transcription factors (Hsfs). In this work, it was explored the role of sHsps in the chilling injury of tomato fruit. The level of transcripts and proteins of cytoplasmic and organellar sHsps was monitored in fruit during ripening and after cold storage (4 weeks at 4°C). Expression of HsfA1, HsfA2, HsfA3, and HsfB1 was also examined. Two cultivars of tomato (Solanum lycopersicum) contrasting in chilling tolerance were assayed: Micro-Tom (chilling-tolerant) and Minitomato (chilling-sensitive). Results showed that sHsps were induced during ripening in fruit from both cultivars. However, sHsps were induced in Micro-Tom fruit but not in Minitomato fruit after storage at a low temperature. In particular, sHsp 17.4-CII and sHsp23.8-M transcripts strongly accumulated in Micro-Tom fruit and HsfA3 transcript diminished after cold storage. These data suggest that sHsps may be involved in the protection mechanisms against chilling stress and substantiate the hypothesis that sHsps may participate in the mechanism of tomato genotype chilling tolerance. © 2016 Scandinavian Plant Physiology Society.

  13. Small heat shock protein Hsp27 prevents heat-induced aggregation of F-actin by forming soluble complexes with denatured actin.

    Science.gov (United States)

    Pivovarova, Anastasia V; Chebotareva, Natalia A; Chernik, Ivan S; Gusev, Nikolai B; Levitsky, Dmitrii I

    2007-11-01

    Previously, we have shown that the small heat shock protein with apparent molecular mass 27 kDa (Hsp27) does not affect the thermal unfolding of F-actin, but effectively prevents aggregation of thermally denatured F-actin [Pivovarova AV, Mikhailova VV, Chernik IS, Chebotareva NA, Levitsky DI & Gusev NB (2005) Biochem Biophys Res Commun331, 1548-1553], and supposed that Hsp27 prevents heat-induced aggregation of F-actin by forming soluble complexes with denatured actin. In the present work, we applied dynamic light scattering, analytical ultracentrifugation and size exclusion chromatography to examine the properties of complexes formed by denatured actin with a recombinant human Hsp27 mutant (Hsp27-3D) mimicking the naturally occurring phosphorylation of this protein at Ser15, Ser78, and Ser82. Our results show that formation of these complexes occurs upon heating and accompanies the F-actin thermal denaturation. All the methods show that the size of actin-Hsp27-3D complexes decreases with increasing Hsp27-3D concentration in the incubation mixture and that saturation occurs at approximately equimolar concentrations of Hsp27-3D and actin. Under these conditions, the complexes exhibit a hydrodynamic radius of approximately 16 nm, a sedimentation coefficient of 17-20 S, and a molecular mass of about 2 MDa. It is supposed that Hsp27-3D binds to denatured actin monomers or short oligomers dissociated from actin filaments upon heating and protects them from aggregation by forming relatively small and highly soluble complexes. This mechanism might explain how small heat shock proteins prevent aggregation of denatured actin and by this means protect the cytoskeleton and the whole cell from damage caused by accumulation of large insoluble aggregates under heat shock conditions.

  14. A contribution to the investigation of the heat load of shock absorbers of semi-active suspensions in motor vehicles

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    Miroslav D. Demić

    2013-10-01

    Full Text Available Dynamic simulation, based on modeling, has a significant role during the process of vehicle development. It is especially important in the first stages of vehicle design, when relevant vehicle parameters are to be defined. Shock absorbers as executive parts of vehicle semi-active suspension systems suffer thermal loads, which may result in damage and degradation of ther characteristics. Therefore,this paper shows an attempt to analyze converting of mechanical work into heat by using the dynamic simulation method. Introduction Shock absorbers are integral elements of semi-active suspension systems for vehicles (hereinafter SASS. They directly affect the active vehicle safety. The role of shock absorbers is to absorb mechanical vibrations transferred from the road and to ensure the safety of passengers in a vehicle. The kinetic energy of vehicle vibrations transforms into mechanical work or heat in shock absorbers. In practice, in the first stage of vehicle development, the shock absorber parameters are chosen from the condition of damping vibrations of vehicles, but their thermal shock loads should be also taken into account. Motor vehicles have complex dynamic characteristics manifested by spatial movement, parameters change during operation, a number of disturbing influences, backlash, friction, hysteresis, etc. The above-mentioned dynamic phenomena, especially vibration, lead to fatigue of driver and users, reduce the life of the vehicle and its systems, etc. The main objective of the system is to reduce the reliance of the above-mentioned negative effects, improving the vehicle behavior on the road and allow the exploitation of vehicles in a wide range of service conditions. Classical systems cannot satisfiy these conditions, so there was a need to introduce new suspension systems with controlled characteristics (briefly called "semi-active", or "active" systems. Oscillatory model of vehicle The differential equations of vibratory motion of

  15. Altered expression of heat shock proteins in embryonal carcinoma and mouse early embryonic cells.

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    Morange, M; Diu, A; Bensaude, O; Babinet, C

    1984-04-01

    In a previous paper, we have shown that in the absence of stress, mouse embryonal carcinoma cells, like mouse early embryo multipotent cells, synthesize high levels of 89- and 70-kilodalton heat shock proteins (HSP)(O. Bensaude and M. Morange, EMBO J. 2:173-177, 1983). We report here the pattern of proteins synthesized after a short period of hyperthermia in various mouse embryonal carcinoma cell lines and early mouse embryo cells. Among the various cell lines tested, two of them, PCC4-Aza R1 and PCC7-S-1009, showed an unusual response in that stimulation of HSP synthesis was not observed in these cells after hyperthermia. However, inducibility of 68- and 105-kilodalton HSP can be restored in PCC7-S-1009 cells after in vitro differentiation triggered by retinoic acid. Similarly, in the early mouse embryo, hyperthermia does not induce the synthesis of nonconstitutive HSP at the eight-cell stage, but induction of the 68-kilodalton HSP does occur at the blastocyst stage. Such a transition in the expression of HSP has already been described for Drosophila melanogaster and sea urchin embryos and recently for mouse embryos. It may be a general property of early embryonic cells.

  16. Phylogenetic analysis of the Trypanosoma genus based on the heat-shock protein 70 gene.

    Science.gov (United States)

    Fraga, Jorge; Fernández-Calienes, Aymé; Montalvo, Ana Margarita; Maes, Ilse; Deborggraeve, Stijn; Büscher, Philippe; Dujardin, Jean-Claude; Van der Auwera, Gert

    2016-09-01

    Trypanosome evolution was so far essentially studied on the basis of phylogenetic analyses of small subunit ribosomal RNA (SSU-rRNA) and glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) genes. We used for the first time the 70kDa heat-shock protein gene (hsp70) to investigate the phylogenetic relationships among 11 Trypanosoma species on the basis of 1380 nucleotides from 76 sequences corresponding to 65 strains. We also constructed a phylogeny based on combined datasets of SSU-rDNA, gGAPDH and hsp70 sequences. The obtained clusters can be correlated with the sections and subgenus classifications of mammal-infecting trypanosomes except for Trypanosoma theileri and Trypanosoma rangeli. Our analysis supports the classification of Trypanosoma species into clades rather than in sections and subgenera, some of which being polyphyletic. Nine clades were recognized: Trypanosoma carassi, Trypanosoma congolense, Trypanosoma cruzi, Trypanosoma grayi, Trypanosoma lewisi, T. rangeli, T. theileri, Trypanosoma vivax and Trypanozoon. These results are consistent with existing knowledge of the genus' phylogeny. Within the T. cruzi clade, three groups of T. cruzi discrete typing units could be clearly distinguished, corresponding to TcI, TcIII, and TcII+V+VI, while support for TcIV was lacking. Phylogenetic analyses based on hsp70 demonstrated that this molecular marker can be applied for discriminating most of the Trypanosoma species and clades.

  17. A preliminary study on functional domains of small heat shock protein Hsp16.3

    Institute of Scientific and Technical Information of China (English)

    CHANG Yong; LI Xuemei; RAO Zihe

    2004-01-01

    Hsp16.3, the small heat shock protein (sHSP) from Mycobacterium tuberculosis, was originally identified as an immunodominant antigen,which possesses three functional domains typical of sHSP family, namely the N-terminal hydrophobic region, α-crystallin domain and a short non-conserved C-terminal extension.To further understand the functional assignment of these independent regions, the three functional domains of Hsp16.3 were defined and the two N- or C-terminal truncated Hsp16.3 remnants were successfully cloned, expressed and purified.In the far and near circular dichroism analysis, the results showed that these remnants expressed similar secondary and tertiary structures to that of wild-type protein.During the reassembly of wild-type nonamer, the C-terminal truncated remnant could interact with the wild-type protein to form hetero-oligomers.When trypsin is used to digest the wild-type Hsp16.3, its α-crystallin domain could resist such degradation.Taken together, these results indicate that the stable secondary and tertiary structures of Hsp16.3 are mainly kept by its α-crystallin domain.

  18. Aberrant Expression and Secretion of Heat Shock Protein 90 in Patients with Bullous Pemphigoid

    Science.gov (United States)

    Tukaj, Stefan; Kleszczyński, Konrad; Vafia, Katerina; Groth, Stephanie; Meyersburg, Damian; Trzonkowski, Piotr; Ludwig, Ralf J.; Zillikens, Detlef; Schmidt, Enno; Fischer, Tobias W.; Kasperkiewicz, Michael

    2013-01-01

    The cell stress chaperone heat shock protein 90 (Hsp90) has been implicated in inflammatory responses and its inhibition has proven successful in different mouse models of autoimmune diseases, including epidermolysis bullosa acquisita. Here, we investigated expression levels and secretory responses of Hsp90 in patients with bullous pemphigoid (BP), the most common subepidermal autoimmune blistering skin disease. In comparison to healthy controls, the following observations were made: (i) Hsp90 was highly expressed in the skin of BP patients, whereas its serum levels were decreased and inversely associated with IgG autoantibody levels against the NC16A immunodominant region of the BP180 autoantigen, (ii) in contrast, neither aberrant levels of circulating Hsp90 nor any correlation of this protein with serum autoantibodies was found in a control cohort of autoimmune bullous disease patients with pemphigus vulgaris, (iii) Hsp90 was highly expressed in and restrictedly released from peripheral blood mononuclear cells of BP patients, and (iv) Hsp90 was potently induced in and restrictedly secreted from human keratinocyte (HaCaT) cells by BP serum and isolated anti-BP180 NC16A IgG autoantibodies, respectively. Our results reveal an upregulated Hsp90 expression at the site of inflammation and an autoantibody-mediated dysregulation of the intracellular and extracellular distribution of this chaperone in BP patients. These findings suggest that Hsp90 may play a pathophysiological role and represent a novel potential treatment target in BP. PMID:23936217

  19. Characterization and Expression of Genes Encoding Three Small Heat Shock Proteins in Sesamia inferens (Lepidoptera: Noctuidae

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    Meng Sun

    2014-12-01

    Full Text Available The pink stem borer, Sesamia inferens (Walker, is a major pest of rice and is endemic in China and other parts of Asia. Small heat shock proteins (sHSPs encompass a diverse, widespread class of stress proteins that have not been characterized in S. inferens. In the present study, we isolated and characterized three S. inferens genes that encode members of the α-crystallin/sHSP family, namely, Sihsp21.4, Sihsp20.6, and Sihsp19.6. The three cDNAs encoded proteins of 187, 183 and 174 amino acids with calculated molecular weights of 21.4, 20.6 and 19.6 kDa, respectively. The deduced amino acid sequences of the three genes showed strong similarity to sHSPs identified in other lepidopteran insects. Sihsp21.4 contained an intron, but Sihsp20.6 and Sihsp19.6 lacked introns. Real-time quantitative PCR analyses revealed that Sihsp21.4 was most strongly expressed in S. inferens heads; Whereas expression of Sihsp20.6 and Sihsp19.6 was highest in eggs. The three S. inferens sHSP genes were up-regulated during low temperature stress. In summary, our results show that S. inferens sHSP genes have distinct regulatory roles in the physiology of S. inferens.

  20. Role of exercise-induced reactive oxygen species in the modulation of heat shock protein response.

    Science.gov (United States)

    Fittipaldi, S; Dimauro, I; Mercatelli, N; Caporossi, D

    2014-01-01

    The multiple roles that have been associated with heat shock proteins (HSPs), inside and outside cells are remarkable. HSPs have been found to play a fundamental role in multiple stress conditions and to offer protection from subsequent insults. Exercise, because of the physiological stresses associated with it, is one of the main stimuli associated with a robust increase of different HSPs in several tissues. Given the combination of physiological stresses induced by exercise, and the 'cross-talk' that occurs between signaling pathways in different tissues, it is likely that exercise induces the HSP expression through a combination of 'stressors', among which reactive oxygen species (ROS) could play a major role. Indeed, although an imbalance between ROS production and antioxidant levels results in oxidative stress, causing damage to lipids, proteins, and nucleic acids with a possible activation of the programed cell death pathway, at moderate concentrations ROS play an important role as regulatory mediators in signaling processes. Many of the ROS-mediated responses actually protect the cells against oxidative stress and re-establish redox homeostasis. The aim of this review is to provide a critical update on the role of exercise-induced ROS in the modulation of the HSP's response, focusing on experimental results from animal and human studies where the link between redox homeostasis and HSPs' expression in different tissues has been addressed.

  1. Protein carbonylation and heat shock proteins in human skeletal muscle: relationships to age and sarcopenia.

    Science.gov (United States)

    Beltran Valls, Maria R; Wilkinson, Daniel J; Narici, Marco V; Smith, Kenneth; Phillips, Bethan E; Caporossi, Daniela; Atherton, Philip J

    2015-02-01

    Aging is associated with a gradual loss of muscle mass termed sarcopenia, which has significant impact on quality-of-life. Because oxidative stress is proposed to negatively impact upon musculoskeletal aging, we investigated links between human aging and markers of oxidative stress, and relationships to muscle mass and strength in young and old nonsarcopenic and sarcopenic adults. Sixteen young and 16 old males (further subdivided into "old" and "old sarcopenic") were studied. The abundance of protein carbonyl adducts within skeletal muscle sarcoplasmic, myofibrillar, and mitochondrial protein subfractions from musculus vastus lateralis biopsies were determined using Oxyblot immunoblotting techniques. In addition, concentrations of recognized cytoprotective proteins (eg, heat shock proteins [HSP], αβ-crystallin) were also assayed. Aging was associated with increased mitochondrial (but not myof