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Hsp70 interactions with membrane lipids regulate cellular functions in health and disease. Prog Lipid Res 2019; 74:18-30. [PMID: 30710597 DOI: 10.1016/j.plipres.2019.01.004] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 01/18/2019] [Accepted: 01/28/2019] [Indexed: 02/07/2023]
Abstract
Beyond guarding the cellular proteome the major stress inducible heat shock protein Hsp70 has been shown to interact with lipids. Non-cytosolic Hsp70 stabilizes membranes during stress challenges and, in pathophysiological states, facilitates endocytosis, counteracts apoptotic mechanisms, sustains survival pathways or represents a signal that can be recognized by the immune system. Disease-coupled lipid-associated functions of Hsp70 may be targeted via distinct subcellular localizations of Hsp70 itself or its specific interacting lipids. With a special focus on interacting lipids, here we discuss localization-dependent roles of the membrane-bound Hsp70 in the context of its therapeutic potential, particularly in cancer and neurodegenerative diseases.
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Yoshihara T, Kobayashi H, Kakigi R, Sugiura T, Naito H. Heat stress-induced phosphorylation of FoxO3a signalling in rat skeletal muscle. Acta Physiol (Oxf) 2016; 218:178-187. [PMID: 27306326 DOI: 10.1111/apha.12735] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Revised: 04/03/2016] [Accepted: 06/09/2016] [Indexed: 01/10/2023]
Abstract
AIM A recent study demonstrated that FoxO3a was directly induced by the overexpression of Hsp72 in rat soleus muscle. However, whether heat stress treatment induces FoxO3a phosphorylation in rat skeletal muscle remains unclear. This study examined the effects of heat stress on the regulation of the FoxO3a signalling pathway in rat skeletal muscle. METHODS Thirty-two male Wistar rats (15 weeks old) were randomly assigned into two groups; sedentary control group (Sed, n = 8) and experimental group (n = 24). After an overnight fast, one leg of each rat (HS leg) in the experimental group was immersed in hot water (43 °C) for 30 min, and the soleus and plantaris muscles in both legs were removed immediately (0 min), 30 min, 60 min, or 24 h after the heat stress (n = 6 each group). The contralateral, non-heated leg in the experimental group served as an internal control (CT leg). RESULTS Heat stress treatment resulted in a significant increase in FoxO3a phosphorylation (Ser253) in the soleus and plantaris muscles of heat-stressed legs after 24 h. Hsp72 expression in heat-stressed legs was significantly higher at 60 min and 24 h in these muscles. Activation of the PTEN/Akt and MEK/ERK pathways was also observed in these muscles immediately after stress, but not at 24 h. There were no differences in FoxO1 and AMPKα phosphorylation in either muscle. CONCLUSION Heat stress in rat skeletal muscle induces phosphorylation of FoxO3a signalling, and it may be related to Hsp72 upregulation, and the activation of the PTEN/Akt and MEK/ERK pathways.
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Affiliation(s)
- T. Yoshihara
- Graduate School of Health and Sports Science; Juntendo University; Inzai Chiba Japan
| | - H. Kobayashi
- Graduate School of Health and Sports Science; Juntendo University; Inzai Chiba Japan
- Mito Medical Center; Tsukuba University Hospital; Mito Ibaraki Japan
| | - R. Kakigi
- Faculty of Medicine; Juntendo University; Bunkyo-ku Tokyo Japan
| | - T. Sugiura
- Faculty of Education; Yamaguchi University; Yamaguchi Yamaguchi Japan
| | - H. Naito
- Graduate School of Health and Sports Science; Juntendo University; Inzai Chiba Japan
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Heider H, Boscheinen O, Scharf KD. A Heat-Stress Pulse Inactivates a 50 kDa Myelin Basic Protein Kinase in Tomato. ACTA ACUST UNITED AC 2014. [DOI: 10.1111/j.1438-8677.1998.tb00725.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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The complex function of hsp70 in metastatic cancer. Cancers (Basel) 2013; 6:42-66. [PMID: 24362507 PMCID: PMC3980608 DOI: 10.3390/cancers6010042] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 12/05/2013] [Accepted: 12/11/2013] [Indexed: 12/26/2022] Open
Abstract
Elevated expression of the inducible heat shock protein 70 (Hsp70) is known to correlate with poor prognosis in many cancers. Hsp70 confers survival advantage as well as resistance to chemotherapeutic agents, and promotes tumor cell invasion. At the same time, tumor-derived extracellular Hsp70 has been recognized as a "chaperokine", activating antitumor immunity. In this review we discuss localization dependent functions of Hsp70 in the context of invasive cancer. Understanding the molecular principles of metastasis formation steps, as well as interactions of the tumor cells with the microenvironment and the immune system is essential for fighting metastatic cancer. Although Hsp70 has been implicated in different steps of the metastatic process, the exact mechanisms of its action remain to be explored. Known and potential functions of Hsp70 in controlling or modulating of invasion and metastasis are discussed.
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Lang BJ, Nguyen L, Nguyen HC, Vieusseux JL, Chai RCC, Christophi C, Fifis T, Kouspou MM, Price JT. Heat stress induces epithelial plasticity and cell migration independent of heat shock factor 1. Cell Stress Chaperones 2012; 17:765-78. [PMID: 22791010 PMCID: PMC3468677 DOI: 10.1007/s12192-012-0349-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 06/21/2012] [Accepted: 06/22/2012] [Indexed: 02/03/2023] Open
Abstract
Current cancer therapies including cytotoxic chemotherapy, radiation and hyperthermic therapy induce acute proteotoxic stress in tumour cells. A major challenge to cancer therapeutic efficacy is the recurrence of therapy-resistant tumours and how to overcome their emergence. The current study examines the concept that tumour cell exposure to acute proteotoxic stress results in the acquisition of a more advanced and aggressive cancer cell phenotype. Specifically, we determined whether heat stress resulted in an epithelial-to-mesenchymal transition (EMT) and/or the enhancement of cell migration, components of an advanced and therapeutically resistant cancer phenotype. We identified that heat stress enhanced cell migration in both the lung A549, and breast MDA-MB-468 human adenocarcinoma cell lines, with A549 cells also undergoing a partial EMT. Moreover, in an in vivo model of thermally ablated liver metastases of the mouse colorectal MoCR cell line, immunohistological analysis of classical EMT markers demonstrated a shift to a more mesenchymal phenotype in the surviving tumour fraction, further demonstrating that thermal stress can induce epithelial plasticity. To identify a mechanism by which thermal stress modulates epithelial plasticity, we examined whether the major transcriptional regulator of the heat shock response, heat shock factor 1 (HSF1), was a required component. Knockdown of HSF1 in the A549 model did not prevent the associated morphological changes or enhanced migratory profile of heat stressed cells. Therefore, this study provides evidence that heat stress significantly impacts upon cancer cell epithelial plasticity and the migratory phenotype independent of HSF1. These findings further our understanding of novel biological downstream effects of heat stress and their potential independence from the classical heat shock pathway.
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Affiliation(s)
- B. J. Lang
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, VIC 3800 Australia
| | - L. Nguyen
- Department of Surgery, Austin Health, The University of Melbourne, Heidelberg, VIC 3084 Australia
| | - H. C. Nguyen
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, VIC 3800 Australia
| | - J. L. Vieusseux
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, VIC 3800 Australia
| | - R. C. C. Chai
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, VIC 3800 Australia
| | - C. Christophi
- Department of Surgery, Austin Health, The University of Melbourne, Heidelberg, VIC 3084 Australia
| | - T. Fifis
- Department of Surgery, Austin Health, The University of Melbourne, Heidelberg, VIC 3084 Australia
| | - M. M. Kouspou
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, VIC 3800 Australia
| | - John T. Price
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, VIC 3800 Australia
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Shin JK, Jeong YT, Jo HC, Kang MY, Chang IS, Baek JC, Park JK, Lee SA, Lee JH, Choi WS, Paik WY. Increased interaction between heat shock protein 27 and mitogen-activated protein kinase (p38 and extracellular signal-regulated kinase) in pre-eclamptic placentas. J Obstet Gynaecol Res 2010; 35:888-94. [PMID: 20149037 DOI: 10.1111/j.1447-0756.2009.01053.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS Heat shock protein 27 (Hsp27) is a well-known stress response protein that is characterized by its phosphorylative capacity. Hsp27 becomes phosphorylated in response to various stimuli through interaction with several different kinases. The purpose of this study was to evaluate the interaction between Hsp27 and mitogen-activated protein kinase (MAPK) (p38, extracellular signal-regulated kinase [ERK], and c-Jun N-terminal kinase) in the human placenta derived from patients with pre-eclampsia. METHODS Western blot analysis was used to examine the levels of expression of Hsp27 and MAPK (p38, ERK, and c-Jun N-terminal kinase). Immunoprecipitation analysis was used to determine the interaction between Hsp27 and MAPK (p38 and ERK). RESULTS Western blotting analysis and immunohistochemistry showed that the expression of Hsp27 and p-Hsp27 in the placental tissues of the pre-eclampsia group were significantly higher than that in the normal pregnancy group. Immunoprecipitation analysis showed that the interaction between Hsp27 and MAPK (p38 and ERK) was significantly increased in the pre-eclamptic placenta tissues. CONCLUSION The interaction between Hsp27 and MAPK was increased, suggesting that phosphorylation of Hsp27 might be induced by p38 and ERK in placentas from patients with pre-eclampsia.
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Affiliation(s)
- Jeong-Kyu Shin
- Department of Obstetrics and Gynecology, College of Medicine, Gyeongsang National University, Jinju, Korea
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Gius D, Mattson D, Bradbury CM, Smart DK, Spitz DR. Thermal stress and the disruption of redox-sensitive signalling and transcription factor activation: possible role in radiosensitization. Int J Hyperthermia 2009; 20:213-23. [PMID: 15195515 DOI: 10.1080/02656730310001619505] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
In spite of ongoing research efforts, the specific mechanism(s) of heat-induced alterations in the cellular response to ionizing radiation (IR) remain ambiguous, in part because they likely involve multiple mechanisms and potential targets. One such group of potential targets includes a class of cytoplasmic signalling and/or nuclear transcription factors known as immediate early response genes, which have been suggested to perform cytotoxic as well as cytoprotective roles during cancer therapy. One established mechanism regulating the activity of these early response elements involves changes in cellular oxidation/reduction (redox) status. After establishing common alterations in early response genes by oxidative stress and heat exposure, one could infer that heat shock may have similarities to other forms of environmental antagonists that induce oxidative stress. In this review, recent evidence supporting a mechanistic link between heat shock and oxidative stress will be summarized. In addition, the hypothesis that one mechanism whereby heat shock alters cellular responses to anticancer agents (including hyperthermic radiosensitization) is through heat-induced disruption of redox-sensitive signalling factors will be discussed.
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Affiliation(s)
- D Gius
- Molecular Radiation Oncology Section, Radiation Oncology Branch, Radiation Oncology Sciences Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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Nadeau SI, Landry J. Mechanisms of Activation and Regulation of the Heat Shock-Sensitive Signaling Pathways. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2007; 594:100-13. [PMID: 17205679 DOI: 10.1007/978-0-387-39975-1_10] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Heat shock (HS), like many other stresses, induces specific and highly regulated signaling cascades that promote cellular homeostasis. The three major mitogen-activated protein kinases (MAPK) and protein kinase B (PKB/Akt) are the most notable of these HS-stimulated pathways. Their activation occurs rapidly and sooner than the transcriptional upregulation of heat shock proteins (Hsp), which generate a transient state of extreme resistance against subsequent thermal stress. The direct connection of these signaling pathways to cellular death or survival mechanisms suggests that they contribute importantly to the HS response. Some of them may counteract early noxious effects of heat, while others may bolster key apoptosis events. The triggering events responsible for activating these pathways are unclear. Protein denaturation, specific and nonspecific receptor activation, membrane alteration and chromatin structure perturbation are potential initiating factors.
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Affiliation(s)
- Sébastien Ian Nadeau
- Centre de recherche en cancérologie de I'Université Laval, L'Hôtel-Dieu de Québec, 9, rue McMahon, Québec, Canada G1 R 2J6
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Sonna LA, Sawka MN, Lilly CM. Exertional heat illness and human gene expression. PROGRESS IN BRAIN RESEARCH 2007; 162:321-46. [PMID: 17645926 DOI: 10.1016/s0079-6123(06)62016-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Microarray analysis of gene expression at the level of RNA has generated new insights into the relationship between cellular responses to acute heat shock in vitro, exercise, and exertional heat illness. Here we discuss the systemic physiology of exertional hyperthermia and exertional heat illness, and compare the results of several recent microarray studies performed in vitro on human cells subjected to heat shock and in vivo on samples obtained from subjects performing exercise or suffering from exertional heat injury. From these comparisons, a concept of overlapping component responses emerges. Namely, some of the gene expression changes observed in peripheral blood mononuclear cells during exertional heat injury can be accounted for by normal cellular responses to heat, exercise, or both; others appear to be specific to the disease state itself. If confirmed in future studies, these component responses might provide a better understanding of adaptive and pathological responses to exercise and exercise-induced hyperthermia, help find new ways of identifying individuals at risk for exertional heat illness, and perhaps even help find rational molecular targets for therapeutic intervention.
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Affiliation(s)
- Larry A Sonna
- Division of Pulmonary and Critical Care Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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Lee KH, Lee CT, Kim YW, Han SK, Shim YS, Yoo CG. Preheating accelerates mitogen-activated protein (MAP) kinase inactivation post-heat shock via a heat shock protein 70-mediated increase in phosphorylated MAP kinase phosphatase-1. J Biol Chem 2005; 280:13179-86. [PMID: 15677475 DOI: 10.1074/jbc.m410059200] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Heat shock (HS) activates mitogen-activated protein (MAP) kinases. Although prior exposure to nonlethal HS makes cells refractory to the lethal effect of a subsequent HS, it is unclear whether this also occurs in MAP kinase activation. This study was undertaken to evaluate the effect of a heat pretreatment on MAP kinase activation by a subsequent HS and to elucidate its possible mechanism. Preheating did not make BEAS-2B cells refractory to extracellular signal-regulated protein kinase (ERK) and c-Jun N-terminal kinase (JNK) activation by a second HS but accelerated their inactivation after HS. The rapid inactivation of ERK and JNK was dependent on de novo protein synthesis and associated with the up-regulation of heat shock protein 70 (HSP70). Moreover, the inhibition of phosphatase activity reversed this rapid inactivation. MAP kinase phosphatase-1 (MKP-1) expression was increased by HS, and the presence of its phosphorylated form (p-MKP-1) correlated with the observed rapid ERK and JNK inactivation. Blocking induction of p-MKP-1 with antisense MKP-1 oligonucleotides suppressed the rapid inactivation of ERK and JNK in preheated cells. HSP70 overexpression caused the early phosphorylation of MKP-1. Moreover, MKP-1 phosphorylation and the rapid inactivation of ERK were inhibited by blocking HSP70 induction in preheated cells. In addition, MKP-1 was insolubilized by HS, and HSP70 associated physically with MKP-1, suggesting that a chaperone effect of HSP70 might have caused the early phosphorylation of MKP-1. These results indicate that preheating accelerated MAP kinase inactivation after a second HS and that this is related to a HSP70-mediated increase in p-MKP-1.
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Affiliation(s)
- Kyoung-Hee Lee
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Korea
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Maroni P, Bendinelli P, Tiberio L, Rovetta F, Piccoletti R, Schiaffonati L. In vivo heat-shock response in the brain: signalling pathway and transcription factor activation. ACTA ACUST UNITED AC 2004; 119:90-9. [PMID: 14597233 DOI: 10.1016/j.molbrainres.2003.08.018] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We analysed the expression of the hsp70 gene, the phosphorylation status of different members of the mitogen-activated protein kinase (MAPK) family, the behaviour of the Akt-GSK3 pathway, as well as the DNA-binding activity of several transcription factors, potential targets of these kinases, in the brain of rats exposed to a fever-like increase in body temperature. Two different brain regions, the cerebellum and the hippocampus, were studied. Hyperthermia caused HSF activation and the induction of hsp70 mRNA and protein to a greater extent in the cerebellum than in the hippocampus. In the cerebellum, ERK1/2 and p38 MAPK phosphorylation were increased by hyperthermia and returned to basal levels during the recovery from heat stress, whereas JNK3 phosphorylation decreased and recovered to above control levels within 60 min of recovery. JNK1 phosphorylation was never modified. In the hippocampus, ERK phosphorylation did not increase but rather decreased, whereas the behaviour of p38 MAPK and JNK was similar to that observed in the cerebellum. Akt phosphorylation increased after hyperthermia and was accompanied by an increased phosphorylation of two substrates, GSK3 and FKHRL1, in both brain areas, with a major effect in the cerebellum. DNA-binding activities of AP-1, NF-kappaB, and MEF2 were activated by heat shock in the cerebellum, whereas only MEF2 was activated in the hippocampus. Our data indicate that a physiologically relevant increase in body temperature induces brain injury and survival response to it as demonstrated by induction of hsp70 gene expression and activation of specific signalling pathways. Reprogramming of gene expression, by the specific transcription factors activated, probably plays a central role in cell adaptation and survival to heat stress. The hippocampus shows less responsiveness to hyperthermia than the cerebellum.
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Affiliation(s)
- Paola Maroni
- Istituto di Patologia Generale, Università degli Studi di Milano, Via Mangiagalli 31, 20133 Milan, Italy
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Chen Q, Li W, Quan Z, Sumpio BE. Modulation of vascular smooth muscle cell alignment by cyclic strain is dependent on reactive oxygen species and P38 mitogen-activated protein kinase. J Vasc Surg 2003; 37:660-8. [PMID: 12618707 DOI: 10.1067/mva.2003.95] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
PURPOSE The aim of this study was to investigate the molecular targets of reactive oxygen species (ROS) and to determine whether cyclic strain induces smooth muscle cell (SMC) alignment via the ROS system. We assessed stretch-induced nicotinamide adenine dinucleotide phosphate (NAD(P)H) oxidase activation and the redox sensitivity of cyclic strain-stimulated activation of the mitogen-activated protein kinase (MAPK) family. METHODS SMCs were seeded on flexible collagen I-coated plates and exposed to cyclic strain. NAD(P)H oxidase activation was measured with lucigenin-enhanced chemiluminescent detection of superoxide. Activation of MAPK was detected by determining phosphorylation of extracellular signal-regulated protein kinase (ERK1/2), c-jun N-terminal kinase (JNK1/2), and p38 MAPK with immunoblotting. In other experiments, SMCs were exposed to diphenylene iodonium (DPI), an NAD(P)H inhibitor, 30 minutes before stretch. MAPK activation and cell orientation were then assessed. RESULTS Cyclic strain elicits a rapid increase in intracellular NADH/NADPH oxidase in SMCs. There was also a rapid and robust phosphorylation of ERK1/2, JNK1/2, and p38 MAPK. Cyclic strain-induced intracellular NAD(P)H generation was almost completely blocked with DPI. DPI also inhibited the strain-induced phosphorylation of ERK1/2, JNK1/2, and p38 MAPK. Both the p38 MAPK specific inhibitor, SB 202190, and DPI blocked cyclic strain-induced cell alignment, but PD98059, an ERK1/2-specific inhibitor, and SP600125, an anthrazolone inhibitor of JNK, did not. CONCLUSION Our results provide evidence that p38 MAPK is a critical component of the oxidant stress ROS-sensitive signaling pathway and plays a crucial role in vascular alignment induced by cyclic stain.
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Affiliation(s)
- Quanhai Chen
- Department of Surgery, Yale University School of Medicine and Connecticut VA Health Care System, 333 Cedar Street, New Haven, CT 06520-8062, USA
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Takuma K, Mori K, Lee E, Enomoto R, Baba A, Matsuda T. Heat shock inhibits hydrogen peroxide-induced apoptosis in cultured astrocytes. Brain Res 2002; 946:232-8. [PMID: 12137926 DOI: 10.1016/s0006-8993(02)02888-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Heat shock proteins (HSPs) have been shown to act as inhibitors of apoptosis, but this anti-apoptotic effect is not known in the central nervous system. Prior heat shock has been demonstrated to protect astrocytes from cell death in a model of reperfusion injury (Brain Res. 735 (1996) 265). The present study examines the mechanism underlying the protective effect of the heat shock. Preincubation of astrocytes at 40 degrees C for 10 min attenuated the hydrogen peroxide (H(2)O(2))-induced decrease in cell viability, DNA ladder formation and nuclear condensation, and these effects were blocked by the protein synthesis inhibitor cycloheximide. The thermal stress inhibited the H(2)O(2)-induced increase in caspase-3 like protease activity, but it did not affect the H(2)O(2)-induced loss of mitochondrial membrane potential. The cytosol prepared from preheated cells did not affect Ca(2+)-induced swelling of mitochondria, a marker of the permeable transition pore. The protective effect of the thermal stress on the H(2)O(2)-induced decrease in cell viability was not affected by the mitogen-activated protein/extracellular signal-regulated kinase kinase inhibitor 2'-amino-3'-methoxyflavone, the phosphatidylinositol-3 kinase inhibitor wortmannin and the NF-kappaB inhibitor pyrrolidinedithiocarbamate. These findings suggest that HSPs inhibit apoptosis via an inhibition of caspase-3 activation without effect on mitochondrial dysfunction.
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Affiliation(s)
- Kazuhiro Takuma
- Department of Analytical Chemistry, Faculty of Pharmaceutical Sciences and High Technology Research Center, Kobe Gakuin University, Japan
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Kim HJ, Song EJ, Lee KJ. Proteomic analysis of protein phosphorylations in heat shock response and thermotolerance. J Biol Chem 2002; 277:23193-207. [PMID: 11886868 DOI: 10.1074/jbc.m201007200] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Heat shock (HS) induces a wide variety of biological processes, including inhibition of protein synthesis, elevated expression of heat shock proteins, induction of thermotolerance, and apoptotic cell death in a dose-dependent manner. We compared phosphorylated proteins in heat-shocked and thermotolerant cells using proteome analysis. After HS treatment of control RIF-1 and their thermotolerant derivatives, TR-RIF-1 cells, cellular proteins were separated by two-dimensional gel electrophoresis and the phosphorylated proteins were detected with the anti-phosphotyrosine antibodies. We found that 93 proteins showed significant changes in phosphorylation between control and thermotolerant cells as a function of recovery time after HS; we identified 81 of these proteins with peptide mass fingerprinting using MALDI-TOF MS after in-gel trypsin digestion. These phosphorylated proteins exhibit various cellular functions, including chaperones, ion channels, signaling molecules, in transcription and translation processes, in amino acid biosynthesis, oxidoreduction, energy metabolism, and cell motility or structure, suggesting that HS turns on the various signaling pathways by activating protein-tyrosine kinases (PTKs). Of these, 20 proteins were previously identified phosphorylated proteins and 64 were newly identified. These proteins can be grouped into three families: 1) proteins highly phosphorylated in TR-RIF-1 cells at basal level and phosphorylated more significantly by HS in RIF-1 than TR-RIF-1; 2) proteins highly phosphorylated in control RIF-1 cells at basal level and phosphorylated more easily by HS in TR-RIF-1 than in RIF-1 cells; and 3) proteins with a similar basal phosphorylation level in both RIF-1 and TR-RIF-1 cells and responding to HS similarly in both cells. Most of the phosphorylated proteins are presumably involved in HS signaling in different ways, with the first and second families of proteins influencing thermotolerance. The possible tyrosine phosphorylation sites, the possible PTKs phosphorylating these proteins, and the proteins binding to these phosphorylated sites were predicted by the Netphos, ScanProsite, and Scansite programs. These results suggest that HS can activate various PTKs and HS responses can be regulated by phosphorylations of proteins having various functions.
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Affiliation(s)
- Hee-Jung Kim
- Center for Cell Signaling Research, Division of Molecular Life Sciences and College of Pharmacy, Ewha Womans University, Seoul 120-750, Korea
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Sonna LA, Gaffin SL, Pratt RE, Cullivan ML, Angel KC, Lilly CM. Effect of acute heat shock on gene expression by human peripheral blood mononuclear cells. J Appl Physiol (1985) 2002; 92:2208-20. [PMID: 11960976 DOI: 10.1152/japplphysiol.01002.2001] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We studied the effect of heat shock on gene expression by normal human cells. Peripheral blood mononuclear cells (PBMCs) were obtained from healthy adults. Paired samples from each subject were subjected to either 20 min of heat shock (43 degrees C) or control (37 degrees C) conditions and then returned to 37 degrees C. RNA was isolated 160 min later, and five representative samples were analyzed on Affymetrix gene chip arrays containing approximately 12,600 probes. A biologically meaningful effect was defined as a statistically significant, twofold or greater difference in expression of sequences that were detected in all five experiments under control (downregulated sequences) or heat shock (upregulated sequences) conditions. Changes occurred in 395 sequences (227 increased by heat shock, 168 decreased), representing 353 Unigene numbers, in every functional category previously implicated in the heat shock response. By RT-PCR, we confirmed the findings for one upregulated sequence (Rad, a G protein) and one downregulated sequence (osteopontin, a cytokine). We conclude that heat shock causes extensive gene expression changes in PBMCs, affecting all functional categories of the heat shock response.
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Affiliation(s)
- Larry A Sonna
- Thermal and Mountain Medicine Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts 01760, USA.
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Abstract
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, contribute significantly to the heat shock response. In the case of p38, the activation leads to the phosphorylation and activation of one of the Hsps, Hsp27. Phosphorylation occurs very early during stress, is tightly regulated, and results from the triggering of a highly specific heat shock-sensing pathway.
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Affiliation(s)
- Sonia Dorion
- Centre de recherche en cancérologie de l'Université Laval, L'Hĵtel-Dieu de Québec, Canada
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Ng DC, Bogoyevitch MA. The mechanism of heat shock activation of ERK mitogen-activated protein kinases in the interleukin 3-dependent ProB cell line BaF3. J Biol Chem 2000; 275:40856-66. [PMID: 11005808 DOI: 10.1074/jbc.m004639200] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
We have investigated heat shock stimulation of MAPK cascades in an interleukin 3-dependent cell line, BaF3. Following exposure to 42 degrees C, the stress-activated JNK MAPKs were phosphorylated and activated, but p38 MAPKs remained unaffected. Surprisingly, heat shock also activated ERK MAPKs in a potent (>60-fold), delayed (>30 min), and sustained (>/=120 min) manner. These characteristics suggested a novel mechanism of ERK MAPK activation and became the focus of this study. A MEK-specific inhibitor, PD98059, inhibited heat shock ERK MAPK activation by >75%. Surprisingly, a role for Ras in the heat shock response was eliminated by the failure of a dominant-negative Ras(Asn-17) mutant to inhibit ERK MAPK activation and the failure to observe increases in Ras.GTP. Heat shock also failed to stimulate activation of A-, B-, and c-Raf. Instead, a serine/threonine phosphatase inhibitor, okadaic acid, activated ERK MAPK in a similar manner to heat shock. Furthermore, pretreatment with suramin, generally recognized as a broad range inhibitor of growth factor receptors, inhibited both okadaic acid-stimulated and heat shock-stimulated ERK MAPK activity by >40%. Inhibiting ERK MAPK activation during heat shock with PD98059 enhanced losses in cell viability. These results demonstrate Ras- and Raf-independent ERK MAPK activation maintains cell viability following heat shock.
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Affiliation(s)
- D C Ng
- Department of Biochemistry, University of Western Australia, Nedlands 6907, Australia
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18
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Abstract
In this study, we evaluated the effects of pervanadate, a tyrosine phosphatase inhibitor, on the regulation and function of heat-shock factor 1 (HSF1) in HeLa cells. We showed that 50-100 microM pervanadate induced the hyperphosphorylation of the latent HSF1, as demonstrated by a retarded mobility of the HSF1 protein in SDS-polyacrylamide gel electrophoresis and as supported by the reversal of this mobility shift upon treatment of the cell extract with acid phosphatase. Pervanadate by itself had no effect on the monomeric stoichiometry and DNA-binding activity of HSF1. Upon heat shock, the pervanadate-induced hyperphosphorylated HSF1 formed DNA-binding trimers and translocated into the nuclear compartment. At high concentration (approximately 500 microM), pervanadate also induced the tyrosine phosphorylation of many cellular proteins and blunted the heat-induced transcription of hsp 70. N-acetyl cysteine inhibited these effects of pervanadate, suggesting a redox-based mechanism for its activity. Analysis of the activation of mitogen-activated protein kinases (MAPKs) using antibodies specific for the phospho-form (activated) of the kinases in Western blot showed that pervanadate activated extracellular signal-regulated kinase (ERK1/2), c-Jun-N-terminal kinase 1/2 (JNK1/2), and p-38 kinase. Pharmacological inhibitors of the ERK1/2 kinase pathway or the p38 kinase had little or no effect on the pervanadate-induced hyperphosphorylation of HSF1. Our results show that hyperphosphorylation of hHSF1 can occur prior to and independent of other events involved in the activation of hHSF1. The possibility that activation of the MAPK signaling cascade, notably JNK, may contribute to the hyperphosphorylation of human HSF1 (hHSF1) is discussed.
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Affiliation(s)
- J Park
- Graduate Program in Cell and Developmental Biology, Rutgers State University of New Jersey, Piscataway, New Jersey, USA
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19
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Bang OS, Ha BG, Park EK, Kang SS. Activation of Akt is induced by heat shock and involved in suppression of heat-shock-induced apoptosis of NIH3T3 cells. Biochem Biophys Res Commun 2000; 278:306-11. [PMID: 11097835 DOI: 10.1006/bbrc.2000.3805] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Heat shock exposure to NIH3T3 cells for 15 min at 45 degrees C activated Akt, which is mediated by PI3-kinase, as evidenced by the significant inhibition of heat-shock-induced phosphorylation by specific inhibitors of PI3-kinase. The phosphorylated Akt was gradually decreased to the basal level within 9 h after heat shock. This resulted in growth arrest, but cell growth could be recovered within 24 h accompanied with a high rate of proliferation. However, heat shock for 60 min failed to activate Akt, resulting in apoptosis. The recovery of cell growth after heat-shock-inducing activation of Akt was completely blocked by wortmannin. Moreover, overexpression of a dominant-negative Akt mutant significantly inhibited the apoptosis-suppressive effect of heat shock, indicating the direct involvement of heat-shock-induced Akt activation in the apoptosis suppression. The results indicate that a signal transduction pathway, namely, PI3-kinase/Akt, may contribute to an apoptosis-suppressive function after heat shock in NIH3T3 cells.
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Affiliation(s)
- O S Bang
- Department of Biology, College of Natural Sciences, Kyungpook National University, Taegu, 702-701, Korea
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20
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Leoni S, Brambilla D, Risuleo G, de Feo G, Scarsella G. Effect of different whole body hyperthermic sessions on the heat shock response in mice liver and brain. Mol Cell Biochem 2000; 204:41-7. [PMID: 10718623 DOI: 10.1023/a:1007053504960] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We examined by Western blots the effect of variations of the heating sessions, such as duration and intensity on the following aspects: 70-kDa heat shock protein (HSP70) and HSP72 induction. Protein ubiquitination PLCgamma , PKCepsilon and PKCalpha levels in murine liver and brain were also studied. Results demonstrated that maximal induction of HSP72 was obtained after heat shock at 43.5 degrees C in both organs. Preconditioning at lower temperatures (either acclimation to 39 degrees C or induction of thermotolerance to 43.5 degrees C with a single exposure to 39 degrees C) attenuated the heat shock response. Hepatic HSP72 induction was elicited only as a consequence of hyperthermia since either fasting or restraint were unable to trigger its synthesis. On the contrary, a ubiquitination decrease of a 31 kDa protein was obtained both after hyperthermia and fasting This indicates that the latter is a more generic response of hepatic cells to noxious stimuli. Analysis of the above mentioned enzymes showed that in liver of naive mice PKCalpha is barely present while PKCepsilon is quite abundant. All hyperthermic treatments caused a general decrease of the latter, except for the heat shock at 43.5 degrees C that caused an increase. PLCgamma decreased after all heating sessions. It is known that hyperthermia in the range of 41-45 degrees C induces apoptotic death in many cell types. Therefore we analyzed the presence of the typical apoptotic DNA ladder. Our data strongly suggest that both hyperthermia and restraint induce necrosis in liver while apoptosis and necrosis become evident in brain. All these effects are still present 24 h from the last heating session: This indicates that in vivo, hyperthermia produces long term modifications of the hepatic cell.
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Affiliation(s)
- S Leoni
- Department of Cellular and Developmental Biology, The University of Rome, La Sapienza, Italy
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21
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Dorion S, Bérubé J, Huot J, Landry J. A short lived protein involved in the heat shock sensing mechanism responsible for stress-activated protein kinase 2 (SAPK2/p38) activation. J Biol Chem 1999; 274:37591-7. [PMID: 10608813 DOI: 10.1074/jbc.274.53.37591] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The stress-activated protein kinase 2 (SAPK2/p38) is activated by various environmental stresses and also by a vast array of agonists including growth factors and cytokines. This implies the existence of multiple proximal signaling pathways converging to the SAPK2/p38 activation cascade. Here, we show that there is a sensing mechanism highly specific to heat shock for activation of SAPK2/p38. After mild heat shock, cells became refractory to reinduction of the SAPK2/p38 pathway by a second heat shock. This was not the result of a toxic effect because the cells remained fully responsive to reinduction by other stresses, cytokines, or growth factors. Neither the activity of SAPK2/p38 itself nor the accumulation of the heat shock proteins was essential in the desensitization process. The cells were not desensitized to heat shock by other treatments that activated SAPK2/p38. Moreover, inhibiting SAPK2/p38 activity during heat shock did not block desensitization. Also, overexpression of HSP70, HSP27, or HSP90 by gene transfection did not cause desensitization, and inhibiting their synthesis after heat shock did not prevent desensitization. Desensitization rather appeared to be linked closely to the turnover of a putative upstream activator of SAPK2/p38. Cycloheximide induced a progressive and eventually complete desensitization. The effect was specific to heat shock and minimally affected activation by other stress inducers. Inhibiting protein degradation with MG132 caused the constitutive activation of SAPK2/p38, which was blocked by a pretreatment with either cycloheximide or heat shock. The results thus indicate that there is a sensing pathway highly specific to heat shock upstream of SAPK2/p38 activation. The pathway appears to involve a short lived protein that is the target of rapid successive up- and down-regulation by heat shock.
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Affiliation(s)
- S Dorion
- Centre de Recherche en Cancérologie de l'Université Laval, Québec G1R 2J6, Canada
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22
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Curry HA, Clemens RA, Shah S, Bradbury CM, Botero A, Goswami P, Gius D. Heat shock inhibits radiation-induced activation of NF-kappaB via inhibition of I-kappaB kinase. J Biol Chem 1999; 274:23061-7. [PMID: 10438474 DOI: 10.1074/jbc.274.33.23061] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Radiation stimulates signaling cascades that result in the activation of several transcription factors that are believed to play a central role in protective response(s) to ionizing radiation (IR). It is also well established that heat shock alters the regulation of signaling cascades and transcription factors and is a potent radiosensitizing agent. To explore the hypothesis that heat disrupts or alters the regulation of signaling factors activated by IR, the effect of heat shock on IR-induced activation of NF-kappaB was determined. Irradiated HeLa cells demonstrated transient increases in NF-kappaB DNA binding activity and NF-kappaB protein nuclear localization. In addition, irradiated cells demonstrated increased I-kappaB phosphorylation and decreased I-kappaBalpha cytoplasmic protein levels, corresponding temporally with the increase of NF-kappaB DNA binding. Heat shock prior to IR inhibited the increase in NF-kappaB DNA binding activity, nuclear localization of NF-kappaB, and the phosphorylation and subsequent degradation of I-kappaB. I-kappaB kinase (IKK) immunoprecipitation assays demonstrated an increase in IKK catalytic activity in response to IR that was inhibited by pretreatment with heat. Kinetic experiments determined that heat-induced inhibition of NF-kappaB activation in response to IR decayed within 5 h after heating. Furthermore, pretreatment with cycloheximide, to block de novo protein synthesis, did not alter heat shock inhibition of IR induction of NF-kappaB. These experiments demonstrate that heat shock transiently inhibits IR induction of NF-kappaB DNA binding activity by preventing IKK activation and suggests a mechanism independent of protein synthesis.
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Affiliation(s)
- H A Curry
- Section of Cancer Biology, Radiation Oncology Center, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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23
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Diamond DA, Parsian A, Hunt CR, Lofgren S, Spitz DR, Goswami PC, Gius D. Redox factor-1 (Ref-1) mediates the activation of AP-1 in HeLa and NIH 3T3 cells in response to heat shock. J Biol Chem 1999; 274:16959-64. [PMID: 10358044 DOI: 10.1074/jbc.274.24.16959] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The early response genes, c-Fos and c-Jun, are induced by environmental stress and are thought to modulate injury processes via the induction of AP-1-dependent target genes. AP-1 activation is thought to be regulated by changes in intracellular oxidation/reduction reactions involving the redox factor-1 (Ref-1) protein. In this study, NIH 3T3 and HeLa cells were used to determine whether heat shock induces the AP-1 transcription factor via signaling pathways involving Ref-1. Reverse transcriptase-polymerase chain reaction analysis and immunoblotting demonstrated that c-Fos and c-Jun were induced 2-10 h following heat shock, and this induction was accompanied by an increase in AP-1 DNA binding. Electrophoretic mobility shift assay extracts immunodepleted of Ref-1 protein demonstrated that the increase in AP-1 DNA-binding activity following heating was dependent upon the presence of Ref-1 and that Ref-1 regulates inducible, but not basal, AP-1 DNA-binding activity. This was confirmed by the restoration of heat-inducible DNA binding upon addition of Ref-1 to immunodepleted extracts. The ability of Ref-1 from heated cells to stimulate AP-1 DNA binding was abolished by chemical oxidation and restored by chemical reduction. These results indicate that heat shock activates c-Fos/c-Jun gene expression and AP-1 DNA binding and suggests that redox-sensitive signal transduction pathways involving Ref-1 may mediate heat-induced alterations in AP-1 activation.
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Affiliation(s)
- D A Diamond
- Section of Cancer Biology, Radiation Oncology Center, Mallinckrodt Institute of Radiology, St. Louis, Missouri 63108, USA
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24
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Abe T, Gotoh S, Higashi K. Higher induction of heat shock protein 72 by heat stress in cisplatin-resistant than in cisplatin-sensitive cancer cells. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1445:123-33. [PMID: 10209264 DOI: 10.1016/s0167-4781(99)00036-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Induction of the heat shock proteins (HSPs) is involved in the increased resistance to cancer therapies such as chemotherapy and hyperthermia. We used two human ovarian cancer cell lines; a cisplatin (CDDP)-sensitive line A2780 and its CDDP-resistant derivative, A2780CP. The concentration of intracellular glutathione (GSH) is higher (2.7-fold increase) in A2780CP cells than in A2780 cells. A mild treatment with a heat stress (42 degrees C for 30 min) induced synthesis of both the heat shock protein 72 (Hsp72) mRNA and the HSP72 protein in A2780CP cells, but not in A2780 cells. In contrast, a severe heat stress (45 degrees C for 30 min) increased synthesis of the HSP72 protein in the two cell lines. The induced level of the HSP72 protein by the severe treatment was higher in A2780CP than in A2780 cells. The gel mobility shift assay showed that DNA binding activities of the heat shock factor (HSF) in the two cell lines were induced similarly and significantly by the mild heat stress. Immunocytochemistry using an anti HSF1 antibody also indicated that mild heat stress activated the HSF1 translocation from the cytosol to the nucleus similarly in the both cell lines. Pretreatment of CDDP-sensitive A2780 cells with N-acetyl-L-cysteine, a precursor of GSH, effectively enhanced induction of the Hsp72 mRNA by the mild heat stress. The present findings demonstrate that induction of the Hsp72 mRNA by the mild heat stress was more extensive in CDDP-resistant A2780CP cells. It is likely that the higher GSH concentration in A2780CP cells plays an important role in promoting Hsp72 gene expression induced by the mild heat stress probably through processes downstream of activation of HSF-DNA binding.
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Affiliation(s)
- T Abe
- Department of Biochemistry, School of Medicine, University of Occupational and Environmental Health, Japan, Iseigaoka 1-1, Yahatanishi-ku, Kitakyushu, Fukuoka 807-8555, Japan.
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25
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Holmberg CI, Roos PM, Lord JM, Eriksson JE, Sistonen L. Conventional and novel PKC isoenzymes modify the heat-induced stress response but are not activated by heat shock. J Cell Sci 1998; 111 ( Pt 22):3357-65. [PMID: 9788877 DOI: 10.1242/jcs.111.22.3357] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In mammalian cells, the heat-induced stress response is mediated by the constitutively expressed heat shock transcription factor 1 (HSF1). Upon exposure to elevated temperatures, HSF1 undergoes several post-translational modifications, including inducible phosphorylation or hyperphosphorylation. To date, neither the role of HSF1 hyperphosphorylation in regulation of the transcriptional activity of HSF1 nor the signaling pathways involved have been characterized. We have previously shown that the protein kinase C (PKC) activator, 12-O-tetradecanoylphorbol 13-acetate (TPA), markedly enhances the heat-induced stress response, and in the present study we elucidate the mechanism by which PKC activation affects the heat shock response in human cells. Our results show that several conventional and novel PKC isoenzymes are activated during the TPA-mediated enhancement of the heat shock response and that the enhancement can be inhibited by the specific PKC inhibitor bisindolylmaleimide I. Furthermore, the potentiating effect of TPA on the heat-induced stress response requires an intact heat shock element in the hsp70 promoter, indicating that PKC-responsive pathways are able to modulate the activity of HSF1. We also demonstrate that PKC is not activated by heat stress per se. These results reveal that PKC exhibits a significant modulatory role of the heat-induced stress response, but is not directly involved in regulation of the heat shock response.
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Affiliation(s)
- C I Holmberg
- Turku Centre for Biotechnology, University of Turku, Abo Akademi University, PO Box 123, FIN-20521 Turku, Finland
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26
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Nagasaka Y, Nakamura K. Modulation of the heat-induced activation of mitogen-activated protein (MAP) kinase by quercetin. Biochem Pharmacol 1998; 56:1151-5. [PMID: 9802325 DOI: 10.1016/s0006-2952(98)00253-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Effects of quercetin, a bioflavonoid compound, on heat-induced activation of mitogen-activated protein (MAP) kinase in rat hepatoma (H4) cells were examined. Quercetin decreased cell viability and induced DNA fragmentation in heat-shocked H4 cells. MAP kinase in heat-shocked cells was activated and reached a peak at 1 hr after the heat shock, and then gradually decreased. Quercetin inhibited the heat-induced activation of MAP kinase observed at 1 hr after heat shock, but markedly stimulated MAP kinase activity at 4 hr after heat shock. Thus, quercetin modulated the heat-induced activation of MAP kinase in a biphasic manner. Present observations indicate that quercetin modulates protein phosphorylation, especially that controled by MAP kinase, in early events of heat shock response.
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Affiliation(s)
- Y Nagasaka
- Department of Nutrition, Yamaguchi Prefectural University, Japan.
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27
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Dimon-Gadal S, Raynaud F, Evain-Brion D, Keryer G. MAP kinase abnormalities in hyperproliferative cultured fibroblasts from psoriatic skin. J Invest Dermatol 1998; 110:872-9. [PMID: 9620292 DOI: 10.1046/j.1523-1747.1998.00203.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Several studies indicate that dermal fibroblasts have a specific role in the pathophysiology of psoriasis. We have previously found that cultured fibroblasts from psoriatic patients are hyperproliferative and have low cyclic AMP-dependent protein kinase activity. In this study, we observed that these cells are also larger than normal. Given the key role of mitogen-activated protein kinases (MAPK) in the regulation of cell proliferation and cytoskeleton function, we characterized MAPK in psoriatic fibroblasts and in normal fibroblasts. Serum and platelet-derived growth factor treatment of serum-deprived fibroblasts led to a larger increase in MAPK activity in psoriatic cells than in normal cells. We then purified MAPK by ion-exchange chromatography. MAPK activity was again found to be significantly higher in psoriatic fibroblasts than in normal cells, both when deprived of serum (p < 0.01) and when stimulated with serum (p < 0.05). Interestingly, 8-bromo-cAMP treatment inhibited serum-stimulated MAPK phosphorylation in normal fibroblasts but had no effect in psoriatic fibroblasts. We observed a temporal variation in nuclear localization of phosphorylated MAPK in cultured fibroblasts stimulated by either serum or platelet-derived growth factor. No difference in the localization of phosphorylated MAPK in normal and psoriatic skins was found. Psoriatic fibroblasts are the first example of a MAPK pathway abnormality in large human benign hyperproliferative cells.
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Affiliation(s)
- S Dimon-Gadal
- Unité INSERM 427, Faculté des Sciences Pharmaceutiques et Biologiques, Paris, France
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28
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Lin RZ, Hu ZW, Chin JH, Hoffman BB. Heat shock activates c-Src tyrosine kinases and phosphatidylinositol 3-kinase in NIH3T3 fibroblasts. J Biol Chem 1997; 272:31196-202. [PMID: 9388274 DOI: 10.1074/jbc.272.49.31196] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
There is increasing evidence that cellular responses to stress are in part regulated by protein kinases, although specific mechanisms are not well defined. The purpose of these experiments was to investigate potential upstream signaling events activated during heat shock in NIH3T3 fibroblasts. Experiments were designed to ask whether heat shock activates p60 c-Src tyrosine kinase or phosphatidylinositol 3-kinase (PI 3-kinase). Using in vitro protein kinase activity assays, it was demonstrated that heat shock stimulates c-Src and PI 3-kinase activity in a time-dependent manner. Also, there was increased PI 3-kinase activity in anti-phosphotyrosine and anti-c-Src immunoprecipitated immunocomplexes from heated cells. Heat shock activated mitogen-activated protein kinase (MAPK) and p70 S6 kinase (S6K) in these cells. The role of PI 3-kinase in regulating heat shock activation of MAPK and p70 S6K was investigated using wortmannin, a specific pharmacological inhibitor of PI 3-kinase. The results demonstrated that wortmannin inhibited heat shock activation of p70 S6K but only partially inhibited heat activation of MAPK. A dominant negative Raf mutant inhibited activation of MAPK by heat shock but did not inhibit heat shock stimulation of p70 S6K. Genistein, a tyrosine kinase inhibitor, and suramin, a growth factor receptor inhibitor, both inhibited heat shock stimulation of MAPK activity and tyrosine phosphorylation of MAPK. Furthermore, a selective epidermal growth factor receptor (EGFR) inhibitor, tryphostin AG1478, and a dominant negative EGFR mutant also inhibited heat shock activation of MAPK. Heat shock induced EGFR phosphorylation. These results suggest that early upstream signaling events in response to heat stress may involve activation of PI 3-kinase and tyrosine kinases, such as c-Src, and a growth factor receptor, such as EGFR; activation of important downstream pathways, such as MAPK and p70 S6K, occur by divergent signaling mechanisms similar to growth factor stimulation.
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Affiliation(s)
- R Z Lin
- Veterans Affairs Palo Alto Health Care System and Geriatrics Research, Education and Clinical Center, Palo Alto, California 94304, USA
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29
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Mosser DD, Caron AW, Bourget L, Denis-Larose C, Massie B. Role of the human heat shock protein hsp70 in protection against stress-induced apoptosis. Mol Cell Biol 1997; 17:5317-27. [PMID: 9271409 PMCID: PMC232382 DOI: 10.1128/mcb.17.9.5317] [Citation(s) in RCA: 699] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Resistance to stress-induced apoptosis was examined in cells in which the expression of hsp70 was either constitutively elevated or inducible by a tetracycline-regulated transactivator. Heat-induced apoptosis was blocked in hsp70-expressing cells, and this was associated with reduced cleavage of the common death substrate protein poly(ADP-ribose) polymerase (PARP). Heat-induced cell death was correlated with the activation of the stress-activated protein kinase SAPK/JNK (c-Jun N-terminal kinase). Activation of SAPK/JNK was strongly inhibited in cells in which hsp70 was induced to a high level, indicating that hsp70 is able to block apoptosis by inhibiting signaling events upstream of SAPK/JNK activation. In contrast, SAPK/JNK activation was not inhibited by heat shock in cells with constitutively elevated levels of hsp70. Cells that constitutively overexpress hsp70 resist apoptosis induced by ceramide, a lipid signaling molecule that is generated by apoptosis-inducing treatments and is linked to SAPK/JNK activation. Similar to heat stress, resistance to ceramide-induced apoptosis occurs in spite of strong SAPK/JNK activation. Therefore, hsp70 is also able to inhibit apoptosis at some point downstream of SAPK/JNK activation. Since PARP cleavage is prevented in both cell lines, these results suggest that hsp70 is able to prevent the effector steps of apoptotic cell death. Processing of the CED-3-related protease caspase-3 (CPP32/Yama/apopain) is inhibited in hsp70-expressing cells; however, the activity of the mature enzyme is not affected by hsp70 in vitro. Caspase processing may represent a critical heat-sensitive target leading to cell death that is inhibited by the chaperoning function of hsp70. The inhibition of SAPK/JNK signaling and apoptotic protease effector steps by hsp70 likely contributes to the resistance to stress-induced apoptosis seen in transiently induced thermotolerance.
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Affiliation(s)
- D D Mosser
- Biotechnology Research Institute, National Research Council of Canada, Montreal, Quebec.
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30
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Paslaru L, Trigon S, Kuhlmann M, Morange M. MAP kinase activation by cyclosporine A. Biochem Biophys Res Commun 1997; 236:599-603. [PMID: 9245696 DOI: 10.1006/bbrc.1997.7017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Short treatment of HeLa cells with cyclosporine A led to the activation in the crude cell extracts of a MAP kinase-like activity. Fractionation by chromatography on a Mono Q column allowed the separation of two activities co-eluting with the MAP kinases ERK1 and ERK2. The activation of these two MAP kinases was demonstrated in Western Blotting by the appearance, after CsA treatment, of two new slowly migrating forms on SDS electrophoretic gels. A similar activation was also obtained in renal epithelial BSC-1 cells and 3T3 fibroblasts. MAP kinase activation might result from a perturbation of calcium homeostasis induced by CsA treatment.
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Affiliation(s)
- L Paslaru
- University of Medicine and Pharmacy Carol Davila, Post-Graduate Department of Biochemistry, Fundeni Hospital, Bucharest, Romania
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31
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Kline MP, Morimoto RI. Repression of the heat shock factor 1 transcriptional activation domain is modulated by constitutive phosphorylation. Mol Cell Biol 1997; 17:2107-15. [PMID: 9121459 PMCID: PMC232058 DOI: 10.1128/mcb.17.4.2107] [Citation(s) in RCA: 243] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Heat shock transcription factor 1 (HSF1) is constitutively expressed in mammalian cells and negatively regulated for DNA binding and transcriptional activity. Upon exposure to heat shock and other forms of chemical and physiological stress, these activities of HSF1 are rapidly induced. In this report, we demonstrate that constitutive phosphorylation of HSF1 at serine residues distal to the transcriptional activation domain functions to repress transactivation. Tryptic phosphopeptide analysis of a collection of chimeric GAL4-HSF1 deletion and point mutants identified a region of constitutive phosphorylation encompassing serine residues 303 and 307. The significance of phosphorylation at serines 303 and 307 in the regulation of HSF1 transcriptional activity was demonstrated by transient transfection and assay of a chloramphenicol acetyltransferase reporter construct. Whereas the transfected wild-type GAL4-HSF1 chimera is repressed for transcriptional activity and derepressed by heat shock, mutation of serines 303 and 307 to alanine results in derepression to a high level of constitutive activity. Similar results were obtained with mutation of these serine residues in the context of full-length HSF1. These data reveal that constitutive phosphorylation of serines 303 and 307 has an important role in the negative regulation of HSF1 transcriptional activity at control temperatures.
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Affiliation(s)
- M P Kline
- Department of Biochemistry, Molecular Biology and Cell Biology, Northwestern University, Evanston, Illinois 60208, USA
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32
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Guay J, Lambert H, Gingras-Breton G, Lavoie JN, Huot J, Landry J. Regulation of actin filament dynamics by p38 map kinase-mediated phosphorylation of heat shock protein 27. J Cell Sci 1997; 110 ( Pt 3):357-68. [PMID: 9057088 DOI: 10.1242/jcs.110.3.357] [Citation(s) in RCA: 525] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have studied the contribution of the individual kinases of the MAP (mitogen-activated protein) kinase family, including ERK (extracellular-signal regulated kinase), JNK/SAPK (c-JUN NH2-terminal kinase/stress-activated protein kinase) and p38, to activation of the HSP27 (heat shock protein 27) kinase MAPKAP kinase-2/3 and to HSP27 phosphorylation in Chinese hamster CCL39 cells stimulated by either growth factors, cytokines or stressing agents. In vitro assays using fractionated cell extracts or immunoprecipitates indicated that only fractions containing ERK or p38, and not those containing JNK/SAPK, had the capacity to activate MAPKAP kinase-2/3. In vivo, however, it appeared that only p38 is an upstream activator of HSP27 phosphorylation after both stress or growth factor stimulation: expression of an interfering mutant of ras, which blocked the activation of ERK by both types of inducers, had no effect on HSP27 phosphorylation and p38 activation; and the cell-permeant specific inhibitor of 038, SB203580, blocked MAPKAP-kinase2/3 activation and HSP27 phosphorylation. HSP27 has been suggested to have a phosphorylation-activated homeostatic function at the actin cytoskeleton level. This raises the possibility that p38 might be directly involved in mediating actin responses to external stimuli. Accordingly, we observed that a prior activation of p38 increased the stability of the actin microfilaments in cells exposed to cytochalasin D. The effect was dependent on the expression of HSP27 and was totally annihilated by blocking the p38 activity with SB203580. The results provide strong support to the idea that activation of p38 during adverse environmental conditions serves a homeostatic function aimed at regulating actin dynamics that would otherwise be destabilized during stress. Its activation during normal agonist stimulation may constitute an additional actin signaling pathway, the importance of which depends on the level of expression of HSP27.
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Affiliation(s)
- J Guay
- Centre de recherche en cancérologie de l'Université Laval. L'Hôtel-Dieu de Québec, Canada
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33
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Wieprecht M, Wieder T, Paul C, Geilen CC, Orfanos CE. Evidence for phosphorylation of CTP:phosphocholine cytidylyltransferase by multiple proline-directed protein kinases. J Biol Chem 1996; 271:9955-61. [PMID: 8626633 DOI: 10.1074/jbc.271.17.9955] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Reversible phosphorylation of CTP:phosphocholine cytidylyltransferase, the rate-limiting enzyme of phosphatidylcholine biosynthesis, is thought to play a role in regulating its activity. In the present study, the hypothesis that proline-directed kinases play a major role in phosphorylating cytidylyltransferase is substantiated using a c-Ha-ras-transfected clone of the human keratinocyte cell line HaCaT. Cellular extracts from epidermal growth factor-stimulated HaCaT cells and from ras-transfected HaCaT cells phosphorylated cytidylyltransferase much stronger as compared with extracts from quiescent HaCaT cells. The tryptic phosphopeptide pattern of cytidylyltransferase phosphorylated by cell-free extracts from ras-transfected HaCaT cells was similar compared with the patterns of cytidylyltransferase phosphorylated by p44mpkmitogen-activated protein kinase and p34cdc2 kinase in vitro, whereas in the case of casein kinase II the pattern was different. Furthermore, in c-Ha-ras-transfected HaCaT cells the in vivo phosphorylation state of cytidylyltransferase was 2-fold higher as compared with untransfected HaCaT cells. This higher phosphorylation of cytidylyltransferase in the ras-transfected clone was reduced to a level below the phosphorylation of cytidylyltransferase in untransfected cells, using olomoucine, a specific inhibitor of proline-directed kinases. The reduced phosphorylation of cytidylyltransferase in olomoucine-treated cells correlated with an enhanced stimulation of enzyme activity by oleic acid.
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Affiliation(s)
- M Wieprecht
- Institute of Molecular Biology and Biochemistry, University Medical Center Benjamin Franklin, Free University of Berlin, Berlin D-12200, Germany
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34
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Varela JCS, Mager WH. Response of Saccharomyces cerevisiae to changes in external osmolarity. MICROBIOLOGY (READING, ENGLAND) 1996; 142 ( Pt 4):721-731. [PMID: 8936301 DOI: 10.1099/00221287-142-4-721] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Joäo C S Varela
- Department of Biochemistry and Molecular Biology, Institute for Molecular Biological Sciences, BioCentrum Amsterdam, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
| | - Willem H Mager
- Department of Biochemistry and Molecular Biology, Institute for Molecular Biological Sciences, BioCentrum Amsterdam, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
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35
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36
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Bensaude O, Bellier S, Dubois MF, Giannoni F, Nguyen VT. Heat-shock induced protein modifications and modulation of enzyme activities. EXS 1996; 77:199-219. [PMID: 8856976 DOI: 10.1007/978-3-0348-9088-5_13] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Upon heat stress, the cell physiology is profoundly altered. The extent of the alterations depends on the severity of the stress and may lead to cell death. The heat shock response is an array of metabolic changes characterized by the impairment of major cellular functions and by an adaptative reprogramming of the cell metabolism. The enhanced synthesis of the HSPs is a spectacular manifestation of this reprogramming. Numerous post translational modifications of proteins occur in response to heat stress and can be related to altered cellular functions. Some proteins are heat-denatured and temporarily inactivated. Heat-denaturation is reversible, chaperones may contribute to the repair. The extent of heat-denaturation depends on the cell metabolism: (a) it is attenuated in thermotolerant cells or in cells overexpressing the appropriate chaperones (b) it is enhanced in energy-deprived cells. Covalent modifications may also rapidly alter protein function. Changes in protein glycosylation, methylation, acetylation, farnesylation, ubiquitination have been found to occur during stress. But protein phosphorylation is the most studied modification. Several protein kinase cascades are activated, among which the various mitogen activated protein kinase (MAP kinase) cascades which are also triggered by a wide range of stimuli. As a possible consequence, stress modifies the phosphorylation status and the activity of components from the transcriptional and translational apparatuses. The same kinases also target key enzymes of the cellular metabolism. Protein denaturation results in constitutive hsp titration, this titration is a signal to trigger the heat-shock gene transcription and to activate some of the protein kinase cascades.
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Affiliation(s)
- O Bensaude
- Génétique Moléculaire, Ecole Normale Supérieure, Paris, France
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37
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Csermely P, Schnaider T, Szántó I. Signalling and transport through the nuclear membrane. BIOCHIMICA ET BIOPHYSICA ACTA 1995; 1241:425-51. [PMID: 8547304 DOI: 10.1016/0304-4157(95)00015-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- P Csermely
- Institute of Biochemistry I., Semmelweis University, Budapest, Hungary
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38
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Chen F, Torres M, Duncan RF. Activation of mitogen-activated protein kinase by heat shock treatment in Drosophila. Biochem J 1995; 312 ( Pt 2):341-9. [PMID: 8526841 PMCID: PMC1136269 DOI: 10.1042/bj3120341] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Heat shock treatment of Drosophila melanogaster tissue culture cells causes increased tyrosine phosphorylation of several 44 kDa proteins, which are identified as Drosophila mitogen-activated protein (MAP) kinases. Tyrosine phosphorylation occurs within 5 min, and is maintained at high levels during heat shock. It decreases to basal levels during recovery, concurrent with the repression of heat shock transcription and heat-shock-protein synthesis. The increased MAP kinase tyrosine phosphorylation is parallelled by increased MAP kinase activity. At least two MAP kinases, DmERK-A and DmERK-B, are identified whose tyrosine phosphorylation increases during heat shock. Thus MAP kinase activation is an immediate early response to heat shock, and its increased activity is maintained throughout heat shock treatment. Protracted MAP kinase activation may contribute to heat shock transcription factor phosphorylation and the numerous metabolic alterations that constitute the heat-shock response.
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Affiliation(s)
- F Chen
- Department of Molecular Pharmacology and Toxicology, University of Southern California School of Pharmacy, Los Angeles 90033, USA
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39
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Engel K, Schultz H, Martin F, Kotlyarov A, Plath K, Hahn M, Heinemann U, Gaestel M. Constitutive activation of mitogen-activated protein kinase-activated protein kinase 2 by mutation of phosphorylation sites and an A-helix motif. J Biol Chem 1995; 270:27213-21. [PMID: 7592979 DOI: 10.1074/jbc.270.45.27213] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
A recently described downstream target of mitogen-activated protein kinases (MAPKs) is the MAPK-activated protein (MAPKAP) kinase 2 which has been shown to be responsible for small heat shock protein phosphorylation. We have analyzed the mechanism of MAPKAP kinase 2 activation by MAPK phosphorylation using a recombinant MAPKAP kinase 2-fusion protein, p44MAPK and p38/40MAPK in vitro and using an epitope-tagged MAPKAP kinase 2 in heat-shocked NIH 3T3 cells. It is demonstrated that, in addition to the known phosphorylation of the threonine residue carboxyl-terminal to the catalytic domain, Thr-317, activation of MAPKAP kinase 2 in vitro and in vivo is dependent on phosphorylation of a second threonine residue, Thr-205, which is located within the catalytic domain and which is highly conserved in several protein kinases. Constitutive activation of MAPKAP kinase 2 is obtained by replacement of both of these threonine residues by glutamic acid. A constitutively active form of MAPKAP kinase 2 is also obtained by deletion of a carboxyl-terminal region containing Thr-317 and the A-helix motif or by replacing the conserved residues of the A-helix. These data suggest a dual mechanism of MAPKAP kinase 2 activation by phosphorylation of Thr-205 inside the catalytic domain and by phosphorylation of Thr-317 outside the catalytic domain involving an autoinhibitory A-helix motif.
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Affiliation(s)
- K Engel
- Max-Delbrück-Centrum für Molekulare Medizin, Berlin, Federal Republic of Germany
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40
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Varela JC, Praekelt UM, Meacock PA, Planta RJ, Mager WH. The Saccharomyces cerevisiae HSP12 gene is activated by the high-osmolarity glycerol pathway and negatively regulated by protein kinase A. Mol Cell Biol 1995; 15:6232-45. [PMID: 7565776 PMCID: PMC230875 DOI: 10.1128/mcb.15.11.6232] [Citation(s) in RCA: 161] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The HSP12 gene encodes one of the two major small heat shock proteins of Saccharomyces cerevisiae. Hsp12 accumulates massively in yeast cells exposed to heat shock, osmostress, oxidative stress, and high concentrations of alcohol as well as in early-stationary-phase cells. We have cloned an extended 5'-flanking region of the HSP12 gene in order to identify cis-acting elements involved in regulation of this highly expressed stress gene. A detailed analysis of the HSP12 promoter region revealed that five repeats of the stress-responsive CCCCT motif (stress-responsive element [STRE]) are essential to confer wild-type induced levels on a reporter gene upon osmostress, heat shock, and entry into stationary phase. Disruption of the HOG1 and PBS2 genes leads to a dramatic decrease of the HSP12 inducibility in osmostressed cells, whereas overproduction of Hog1 produces a fivefold increase in wild-type induced levels upon a shift to a high salt concentration. On the other hand, mutations resulting in high protein kinase A (PKA) activity reduce or abolish the accumulation of the HSP12 mRNA in stressed cells. Conversely, mutants containing defective PKA catalytic subunits exhibit high basal levels of HSP12 mRNA. Taken together, these results suggest that HSP12 is a target of the high-osmolarity glycerol (HOG) response pathway under negative control of the Ras-PKA pathway. Furthermore, they confirm earlier observations that STRE-like sequences are responsive to a broad range of stresses and that the HOG and Ras-PKA pathways have antagonistic effects upon CCCCT-driven transcription.
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Affiliation(s)
- J C Varela
- Department of Biochemistry and Molecular Biology, Instituut voor Moleculair Biologische Wetenschappen, BioCentrum Amsterdam, Vrije Universiteit, The Netherlands
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41
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Gould GW, Cuenda A, Thomson FJ, Cohen P. The activation of distinct mitogen-activated protein kinase cascades is required for the stimulation of 2-deoxyglucose uptake by interleukin-1 and insulin-like growth factor-1 in KB cells. Biochem J 1995; 311 ( Pt 3):735-8. [PMID: 7487926 PMCID: PMC1136064 DOI: 10.1042/bj3110735] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The uptake of 2-deoxyglucose into KB cells was stimulated about 2-fold by interleukin-1 (IL1), anisomycin or insulin-like growth factor-1 (IGF1). Stimulation by IL1 and anisomycin was prevented by SB 203580, a specific inhibitor of the mitogen-activated protein (MAP) kinase homologue termed 're-activating kinase' [RK; also known as p38, p40 and CSBP (cytokine synthesis anti-inflammatory-drug-binding protein)], but was unaffected by PD 98059, a specific inhibitor of the activation of the classical MAP kinase pathway. In contrast, the stimulation of 2-deoxyglucose uptake by IGF1 was blocked by PD 98059 and unaffected by SB 203580. Consistent with these observations, IL1 and anisomycin were potent activators of MAP kinase-activated protein (MAPKAP) kinase-2, a physiological substrate of RK, whereas IGF1 was only a very weak activator of MAPKAP kinase-2. Conversely, IGF1 was a stronger activator of p42 MAP kinase than IL1 or anisomycin. These results imply that the activation of distinct MAP kinase pathways is required for the stimulation of glucose transport by IL1/anisomycin and IGF1 in KB cells, and suggest that the combined use of SB 203580 and PD 98059 is a powerful new approach to explore the roles of different MAP kinase cascades in cell regulation.
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Affiliation(s)
- G W Gould
- Division of Biochemistry and Molecular Biology, University of Glasgow, U.K
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42
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Venetianer A, Dubois MF, Nguyen VT, Bellier S, Seo SJ, Bensaude O. Phosphorylation state of the RNA polymerase II C-terminal domain (CTD) in heat-shocked cells. Possible involvement of the stress-activated mitogen-activated protein (MAP) kinases. EUROPEAN JOURNAL OF BIOCHEMISTRY 1995; 233:83-92. [PMID: 7588777 DOI: 10.1111/j.1432-1033.1995.083_1.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
RNA polymerase (RNAP) II is a multisubunit enzyme composed of several different subunits. Phosphorylation of the C-terminal domain (CTD) of the largest subunit is tightly regulated. In quiescent or in exponentially growing cells, both the unphosphorylated (IIa) and the multiphosphorylated (IIo) subunits of RNAP II are found in equivalent amounts as the result of the equilibrated antagonist action of protein kinases and phosphatases. In Drosophila and mammalian cells, heat shock markedly modifies the phosphorylation of the RNAP II CTD. Mild heat shocks result in dephosphorylation of the RNAP II CTD. This dephosphorylation is blocked in the presence of actinomycin D, as the CTD dephosphorylation observed in the presence of protein kinase inhibitors. Thus, heat shock might inactivate CTD kinases which are operative at normal growth temperatures, as some protein kinase inhibitors do. In contrast, severe heat shocks are found to increase the amount of phosphorylated subunit independently of the transcriptional activity of the cells. Mild and severe heat shocks activate protein kinases, which then phosphorylate, in vitro and in vivo, the CTD fused to beta-galactosidase. Most of the heat-shock-activated CTD kinases present in cytosolic lysates co-purify with the activated mitogen-activated protein (MAP) kinases, p42mapk and p44mapk. The weak CTD kinase activation occurring upon mild heat shock might be insufficient to compensate for the heat inactivation of the already existing CTD kinases. However, under severe stress, the MAP kinases are strongly heat activated and might prevail over the phosphatases. A survey of different cells and different heat-shock conditions shows that the RNAP II CTD hyperphosphorylation rates follow the extent of MAP kinase activation. These observations lead to the proposal that the RNAP II CTD might be an in vivo target for the activated p42mapk and p44mapk MAP kinases.
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Affiliation(s)
- A Venetianer
- Institute of Genetics, Biological Research Center, Hungarian Academy of Sciences, Szeged, Hungary
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43
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Ovelgönne H, Van Wijk R. Modulation of HSP68 gene expression after heat shock in thermosensitized and thermotolerant cells is not solely regulated by binding of HSF to HSE. Int J Hyperthermia 1995; 11:719-32. [PMID: 7594822 DOI: 10.3109/02656739509022503] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Induction of heat shock proteins (HSP) is generally regarded as a consequence of binding of the heat shock transcription factor (HSF) to heat shock elements (HSE), i.e. to be a single hit induction. The activation of HSF and the induction of HSP68 mRNA were studied in non pretreated Reuber H35 rat hepatoma cells in a thermosensitized and in a thermotolerant state. It was found that HSF in Reuber H35 hepatoma cells already acquires maximum DNA binding activity at temperatures that are too low to induce HSP68 mRNA. Directly following heat shock cells are in a transient thermosensitized state. In this state a second stress of lower impact leads to even higher production of HSP68, which corresponds with a decreased decay rate HSF-HSE binding. Directly following the thermosensitized state cells become refractory. In this period a second stress of the same impact does lead to HSF-HSE binding but the production of HSP68 mRNA is lowered, while only higher-impact stresses lead to high inductions of the said mRNA. The results indicate that regulation of HSP68 gene transcription involves at least one additional event outside the acquisition of DNA-binding activity by HSF and that this process can thus be described as a multiple-hit occurrence.
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Affiliation(s)
- H Ovelgönne
- Utrecht University, Department of Molecular Cell Biology, The Netherlands
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44
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Cornelius G, Engel M. Stress causes induction of MAP kinase-specific phosphatase and rapid repression of MAP kinase activity in Drosophila. Cell Signal 1995; 7:611-5. [PMID: 8588977 DOI: 10.1016/0898-6568(95)00027-m] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Heat shock and chemical stress induce activation of heat shock (stress) genes and synthesis of heat shock proteins. It is not yet fully understood which molecular mechanism leads to activation. Probably denatured proteins play an important role in activating the transcription factor (HSF), but on the other hand there are many hints that a phosphorylation event is involved, too. During a search for a possible signal transduction system in Drosophila Schneider 2 cells we analysed the response of the mitogen-activated protein (MAP) kinase after stress and its regulation by phosphatases. We show here that stress activates a MAP kinase-specific phosphatase in Drosophila and inhibits MAP kinase activity.
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Affiliation(s)
- G Cornelius
- Institute for Genetics, Saarland University, Federal Republic of Germany
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45
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Trigon S, Morange M. Different carboxyl-terminal domain kinase activities are induced by heat-shock and arsenite. Characterization of their substrate specificity, separation by Mono Q chromatography, and comparison with the mitogen-activated protein kinases. J Biol Chem 1995; 270:13091-8. [PMID: 7768904 DOI: 10.1074/jbc.270.22.13091] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
In response to heat-shock and chemical treatments, cells undergo profound biochemical changes such as modifications in protein phosphorylation in order to resist the new, unfavorable growth conditions. We have previously shown that in HeLa cells a protein kinase (HS-CTD kinase) activity is induced rapidly after a heat or sodium arsenite shock. This kinase activity is able to phosphorylate a synthetic peptide composed of four repeats of the motif Ser-Pro-Thr-Ser-Pro-Ser-Tyr, a motif highly repeated in the carboxyl-terminal domain (CTD) of the largest subunit of eukaryotic RNA polymerase II. In this paper, we designed a new experimental procedure to characterize the substrate specificity of this kinase activity. We show that HS-CTD kinase activity phosphorylates a consensus sequence (-P-X-S/T-P-) which is similar to the sequence phosphorylated by extracellular regulated protein kinases (also called mitogen-activated protein kinases). However, there is a slight but reproducible difference between these kinases in their use of serine or threonine as the phosphate acceptor. Mono Q chromatography allows the separation of five stress-induced CTD kinase activities, two of which coelute with active mitogen-activated protein kinase forms revealed by Western blotting with anti ERK1-ERK2 antibodies. The other three CTD kinase activities induced after a stress are distinct from ERK1 and ERK2 and have different enzymatic properties. The molecular nature of these HS-CTD kinases and the physiological significance of their activation during stress remain to be determined.
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Affiliation(s)
- S Trigon
- Unité de Génétique moléculaire, Ecole Normale Superieure, Paris, France
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46
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Corton JM, Gillespie JG, Hawley SA, Hardie DG. 5-aminoimidazole-4-carboxamide ribonucleoside. A specific method for activating AMP-activated protein kinase in intact cells? EUROPEAN JOURNAL OF BIOCHEMISTRY 1995; 229:558-65. [PMID: 7744080 DOI: 10.1111/j.1432-1033.1995.tb20498.x] [Citation(s) in RCA: 933] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The AMP-activated protein kinase (AMPK) is believed to protect cells against environmental stress (e.g. heat shock) by switching off biosynthetic pathways, the key signal being elevation of AMP. Identification of novel targets for the kinase cascade would be facilitated by development of a specific agent for activating the kinase in intact cells. Incubation of rat hepatocytes with 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR) results in accumulation of the monophosphorylated derivative (5-aminoimidazole-4-carboxamide ribonucleoside; ZMP) within the cell. ZMP mimics both activating effects of AMP on AMPK, i.e. direct allosteric activation and promotion of phosphorylation by AMPK kinase. Unlike existing methods for activating AMPK in intact cells (e.g. fructose, heat shock), AICAR does not perturb the cellular contents of ATP, ADP or AMP. Incubation of hepatocytes with AICAR activates AMPK due to increased phosphorylation, causes phosphorylation and inactivation of a known target for AMPK (3-hydroxy-3-methylglutaryl-CoA reductase), and almost total cessation of two of the known target pathways, i.e. fatty acid and sterol synthesis. Incubation of isolated adipocytes with AICAR antagonizes isoprenaline-induced lipolysis. This provides direct evidence that the inhibition by AMPK of activation of hormone-sensitive lipase by cyclic-AMP-dependent protein kinase, previously demonstrated in cell-free assays, also operates in intact cells. AICAR should be a useful tool for identifying new target pathways and processes regulated by the protein kinase cascade.
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Affiliation(s)
- J M Corton
- Department of Biochemistry, University, Dundee, Scotland
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47
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Corton JM, Gillespie JG, Hawley SA, Hardie DG. 5-Aminoimidazole-4-Carboxamide Ribonucleoside. A Specific Method for Activating AMP-Activated Protein Kinase in Intact Cells? ACTA ACUST UNITED AC 1995. [DOI: 10.1111/j.1432-1033.1995.0558k.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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48
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Keyse SM. An emerging family of dual specificity MAP kinase phosphatases. BIOCHIMICA ET BIOPHYSICA ACTA 1995; 1265:152-60. [PMID: 7696343 DOI: 10.1016/0167-4889(94)00211-v] [Citation(s) in RCA: 210] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- S M Keyse
- ICRF Molecular Pharmacology Unit, Biomedical Research Centre, Ninewells Hospital, Dundee, UK
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49
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Heider H, Widmer HR. Okadaic acid potentiates heat-induced activation of erk2. BIOCHIMICA ET BIOPHYSICA ACTA 1995; 1265:196-200. [PMID: 7696349 DOI: 10.1016/0167-4889(94)00227-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Subjecting exponentially growing HeLa cells to heat shock at 45 degrees C for 30 min leads to retarded migration of erk1 and erk2, as revealed on immunoblots indicating their activation. Renaturation gels confirmed activation of erk2 but not erk1. Treatment of cells with okadaic acid (OA) alone marginally upregulated erk1 and erk2, whereas simultaneous exposure to heat shock and OA led to a considerably augmented response for erk2 which was approximately 3-fold higher than the sum of heat- and OA-induced activation. Chronic treatment of cells with 12-O-tetradecanoyl-phorbol 13-acetate marginally diminished the extent of erk2 stimulation, but had no influence on the OA-induced potentiation of heat-induced erk2 activity.
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Affiliation(s)
- H Heider
- Institute of Anatomy, University of Berne, Switzerland
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50
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Peterson SR, Jesch SA, Chamberlin TN, Dvir A, Rabindran SK, Wu C, Dynan WS. Stimulation of the DNA-dependent protein kinase by RNA polymerase II transcriptional activator proteins. J Biol Chem 1995; 270:1449-54. [PMID: 7836414 DOI: 10.1074/jbc.270.3.1449] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The DNA-dependent protein kinase (DNA-PK) phosphorylates RNA polymerase II and a number of transcription factors. We now show that the activity of DNA-PK is directly stimulated by certain transcriptional activator proteins, including the human heat shock transcription factor 1 (HSF1) and a transcriptionally active N-terminal 147 amino acid GAL4 derivative. Stimulation of DNA-PK activity required specific sequences in the activator proteins outside the minimal DNA binding domains. The stimulation of DNA-PK activity also required DNA and was greater with DNA containing relevant activator binding sites. Comparison of different HSF binding fragments showed that optimal stimulation occurred when two HSF binding sites were present. Stimulation with HSF and GAL4 was synergistic with Ku protein, another regulator of DNA-PK activity. DNA-PK is tightly associated with the transcriptional template, and an increase in its activity could potentially influence transcription through the phosphorylation of proteins associated with the transcription complex.
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Affiliation(s)
- S R Peterson
- Department of Chemistry and Biochemistry, University of Colorado, Boulder 80309-0215
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