scholarly journals Activation of Heat Shock Genes Is Not Necessary for Protection by Heat Shock Transcription Factor 1 against Cell Death Due to a Single Exposure to High Temperatures

2003 ◽  
Vol 23 (16) ◽  
pp. 5882-5895 ◽  
Author(s):  
Sachiye Inouye ◽  
Kensaku Katsuki ◽  
Hanae Izu ◽  
Mitsuaki Fujimoto ◽  
Kazuma Sugahara ◽  
...  
Keyword(s):  
Cell Death ◽  
Heat Shock ◽  
Heat Shock Proteins ◽  
Heat Shock Response ◽  
Single Exposure ◽  
Heat Shock Genes ◽  
Amino Terminal ◽  
Shock Response ◽  
Shock Proteins

ABSTRACT Heat shock response, which is characterized by the induction of a set of heat shock proteins, is essential for induced thermotolerance and is regulated by heat shock transcription factors (HSFs). Curiously, HSF1 is essential for heat shock response in mammals, whereas in avian HSF3, an avian-specific factor is required for the burst activation of heat shock genes. Amino acid sequences of chicken HSF1 are highly conserved with human HSF1, but those of HSF3 diverge significantly. Here, we demonstrated that chicken HSF1 lost the ability to activate heat shock genes through the amino-terminal domain containing an alanine-rich sequence and a DNA-binding domain. Surprisingly, chicken and human HSF1 but not HSF3 possess a novel function that protects against a single exposure to mild heat shock, which is not mediated through the activation of heat shock genes. Overexpression of HSF1 mutants that could not bind to DNA did not restore the susceptibility to cell death in HSF1-null cells, suggesting that the new protective role of HSF1 is mediated through regulation of unknown target genes other than heat shock genes. These results uncover a novel role of vertebrate HSF1, which has been masked underthe roles of heat shock proteins.

scholarly journals Activation of the heat shock response in a primary cellular model of motoneuron neurodegeneration-evidence for neuroprotective and neurotoxic effects

2009 ◽  
Vol 14 (2) ◽  
Author(s):  
Bernadett Kalmar ◽  
Linda Greensmith
Keyword(s):  
Cell Death ◽  
Heat Shock ◽  
Heat Shock Response ◽  
Apoptotic Cell ◽  
Experimental Conditions ◽  
Pharmacological Agents ◽  
Shock Response ◽  
Induced Apoptosis ◽  
Shock Proteins ◽  
The Relationship

AbstractPharmacological up-regulation of heat shock proteins (hsps) rescues motoneurons from cell death in a mouse model of amyotrophic lateral sclerosis. However, the relationship between increased hsp expression and neuronal survival is not straightforward. Here we examined the effects of two pharmacological agents that induce the heat shock response via activation of HSF-1, on stressed primary motoneurons in culture. Although both arimoclomol and celastrol induced the expression of Hsp70, their effects on primary motoneurons in culture were significantly different. Whereas arimoclomol had survival-promoting effects, rescuing motoneurons from staurosporin and H2O2 induced apoptosis, celastrol not only failed to protect stressed motoneurons from apoptosis under same experimental conditions, but was neurotoxic and induced neuronal death. Immunostaining of celastrol-treated cultures for hsp70 and activated caspase-3 revealed that celastrol treatment activates both the heat shock response and the apoptotic cell death cascade. These results indicate that not all agents that activate the heat shock response will necessarily be neuroprotective.

scholarly journals SECOND ANOXIA-REOXYGENATION DOES NOT CAUSE THE APOPTOTIC CELL DEATH OF NEONATAL CARDIOMYOCYTES: POSSIBLE ROLE OF CHANGES OF mRNA EXPRESSION OF CYTOPROTECTIVE GENES

2009 ◽  
Vol 55 (1) ◽  
pp. 19-26
Author(s):  
O.V. Surova ◽  
◽  
V.E. Dosenko ◽  
V.S. Nagibin ◽  
L.V. Tumanovskaya ◽  
...  
Keyword(s):  
Cell Death ◽  
Heat Shock ◽  
Heat Shock Proteins ◽  
Apoptotic Cell ◽  
First Episode ◽  
Mrna Levels ◽  
Neonatal Cardiomyocytes ◽  
Genes Expression ◽  
Shock Proteins

The cells death and genes expression in neonatal cardiomyocytes culture at two anoxia-reoxygenation modeling were investigated. The primary culture of neonatal cardiomyocytes was under­gone 30 min of anoxia followed by 24 h (A-R1) and the second anoxia-reoxygenation – 30 min and 60 min respectively (A-R2). The percentages of living, necrotic, apoptotic and autophagic cells were determined by staining with bis-benzimide, propidium iodide and monodansylcadaverine. Anoxia-reoxygenation sig­nificantly influenced the ratio of living, necrotic, apoptotic and autophagic cells both at its first A-R1 and second A-R2 epi­sodes. It was shown that the main mechanism of cell death after the both periods of anoxia-reoxygenation is necrosis. The changes of mRNA levels of genes of heat shock proteins HSP70 and HSP90, antiapoptotic protein Bcl2 and key regulator of au-tophagy FRAP in cardiomyocytes culture were established. The data obtained allow to make suggestion that in 24 h after the first episode of anoxia-reoxygenation A-R1 the overexpression of heat shock proteins starts the cascade of reactions that causes the necrotic cell death prevalent and the blocking of apoptotic program at second anoxia-reoxygenation A-R2.

scholarly journals Characterizing Gene Copy Number of Heat Shock Protein Gene Families in the Emerald Rockcod, Trematomus bernacchii

Genes ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 867
Author(s):  
Anthony D. Tercero ◽  
Sean P. Place
Keyword(s):  
Heat Shock ◽  
Gene Duplication ◽  
Heat Shock Proteins ◽  
Heat Shock Response ◽  
Copy Number ◽  
Gene Families ◽  
Gene Copy ◽  
Shock Response ◽  
Trematomus Bernacchii ◽  
Shock Proteins

The suborder Notothenioidae is comprised of Antarctic fishes, several of which have lost their ability to rapidly upregulate heat shock proteins in response to thermal stress, instead adopting a pattern of expression resembling constitutive genes. Given the cold-denaturing effect that sub-zero waters have on proteins, evolution in the Southern Ocean has likely selected for increased expression of molecular chaperones. These selective pressures may have also enabled retention of gene duplicates, bolstering quantitative output of cytosolic heat shock proteins (HSPs). Given that newly duplicated genes are under more relaxed selection, it is plausible that gene duplication enabled altered regulation of such highly conserved genes. To test for evidence of gene duplication, copy number of various isoforms within major heat shock gene families were characterized via qPCR and compared between the Antarctic notothen, Trematomus bernacchii, which lost the inducible heat shock response, and the non-Antarctic notothen, Notothenia angustata, which maintains an inducible heat shock response. The results indicate duplication of isoforms within the hsp70 and hsp40 super families have occurred in the genome of T. bernacchii. The findings suggest gene duplications may have been critical in maintaining protein folding efficiency in the sub-zero waters and provided an evolutionary mechanism of alternative regulation of these conserved gene families.

Physical Activity, Muscle, and the HSP70 Response

1998 ◽  
Vol 23 (3) ◽  
pp. 245-260 ◽  
Author(s):  
J. Lon Kilgore ◽  
Timothy I. Musch ◽  
Christopher R. Ross
Keyword(s):  
Physical Activity ◽  
Heat Shock ◽  
Heat Shock Proteins ◽  
Heat Shock Protein ◽  
Heat Shock Response ◽  
Shock Response ◽  
Potential Applications ◽  
Shock Proteins ◽  
External Stimuli ◽  
Exercise And Training

Selye (1936) described how organisms react to various external stimuli (i.e., stressors). These reactions generally follow a programmed series of events and help the organism adapt to the imposed stress. The heat shock response is a common cellular reaction to external stressors, including physical activity. A characteristic set of proteins is synthesised shortly after the organism is exposed to stress. Researchers have not determined how heat shock proteins affect the exercise response. However, their role in adaptation to exercise and training might he inferred, since the synthetic patterns correlate well with the stress adaptation syndrome that Selye described. This review addresses the 70 kilodalton heat shock protein family (HSP70), the most strongly induced heat shock proteins. This paper provides an overview of the general heat shock response and a brief review of literature on HSP70 function, structure, regulation, and potential applications. Potential applications in health, exercise, and medicine are provided. Key words: heat shock, protein, exercise

Heat shock proteins affect RNA processing during the heat shock response of Saccharomyces cerevisiae

1991 ◽  
Vol 11 (2) ◽  
pp. 1062-1068
Author(s):  
H J Yost ◽  
S Lindquist
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Protein Synthesis ◽  
Heat Shock ◽  
Heat Shock Proteins ◽  
Heat Shock Response ◽  
Rna Splicing ◽  
Yeast Cells ◽  
Yeast Saccharomyces Cerevisiae ◽  
Shock Response ◽  
Shock Proteins

In the yeast Saccharomyces cerevisiae, the splicing of mRNA precursors is disrupted by a severe heat shock. Mild heat treatments prior to severe heat shock protect splicing from disruption, as was previously reported for Drosophila melanogaster. In contrast to D. melanogaster, protein synthesis during the pretreatment is not required to protect splicing in yeast cells. However, protein synthesis is required for the rapid recovery of splicing once it has been disrupted by a sudden severe heat shock. Mutations in two classes of yeast hsp genes affect the pattern of RNA splicing during the heat shock response. First, certain hsp70 mutants, which overproduce other heat shock proteins at normal temperatures, show constitutive protection of splicing at high temperatures and do not require pretreatment. Second, in hsp104 mutants, the recovery of RNA splicing after a severe heat shock is delayed compared with wild-type cells. These results indicate a greater degree of specialization in the protective functions of hsps than has previously been suspected. Some of the proteins (e.g., members of the hsp70 and hsp82 gene families) help to maintain normal cellular processes at higher temperatures. The particular function of hsp104, at least in splicing, is to facilitate recovery of the process once it has been disrupted.

Activation of HSF and selective increase in heat-shock proteins by acute dexamethasone treatment

2000 ◽  
Vol 278 (4) ◽  
pp. H1091-H1097 ◽  
Author(s):  
L. Sun ◽  
J. Chang ◽  
S. R. Kirchhoff ◽  
A. A. Knowlton
Keyword(s):  
Heat Shock ◽  
Heat Shock Proteins ◽  
Heat Shock Response ◽  
Cardiac Myocyte ◽  
Adult Rat ◽  
Shock Response ◽  
Cytokine Tumor Necrosis Factor ◽  
Factor Α ◽  
Shock Proteins ◽  
Selective Increase

Heat-shock proteins (HSPs) are an important family of endogenous protective proteins, which increase in response to myocardial ischemia and other stresses. Overexpression of HSP72 is cardioprotective. We were interested in the regulation of heat-shock factor (HSF), the transcription factor for HSP genes. Previously we have observed that the inflammatory cytokine tumor necrosis factor-α increases HSP72 levels and postulated that dexamethasone might effect the heat shock response. In the adult rat cardiac myocyte we found that treatment with either low (10 μM)- or high (100 μM)-dose dexamethasone activated HSF by 2–6 h as determined by gel shift assay without evidence of cytotoxicity. Although HSF activation is a key step in expression of HSP72, this may not result in an increase in HSP72. We found that 10 μM dexamethasone increased HSP72 38%, and 100 μM dexamethasone increased HSP72 62% ( P < 0.05). HSP27 and HSP60 were unchanged. The selective increase in HSP72 was associated with protection of the cardiac myocytes from hypoxia and reoxygenation. We conclude that dexamethasone is a novel inducer of the heat shock response.

Sign in / Sign up

Export Citation Format

Share Document