scholarly journals Expression of a heat-inducible gene of the HSP70 family in human myelomonocytic cells: regulation by bacterial products and cytokines

Blood ◽  
1991 ◽  
Vol 77 (3) ◽  
pp. 579-586
Author(s):  
G Fincato ◽  
N Polentarutti ◽  
A Sica ◽  
A Mantovani ◽  
F Colotta
Keyword(s):  
Heat Shock ◽  
Transcriptional Activation ◽  
Blot Analysis ◽  
Human Peripheral Blood ◽  
Hsp70 Expression ◽  
Hsp70 Gene ◽  
Blood Leukocytes ◽  
Hsp70 Mrna ◽  
Hsp70 Family ◽  
Myelomonocytic Cells

In this study we have examined the expression of a heat-shock protein (HSP) 70 gene in normal human peripheral blood leukocytes. Northern blot analysis showed that appreciable levels of hsp70 mRNA are present in monocytes and granulocytes, whereas transcript levels were barely detectable or absent in lymphocytes. Monocytes functionally activated by bacterial lipopolysaccharide (LPS) showed an early (15 minutes) increase of hsp70 transcripts that was shown, by actinomycin D blocking and nuclear run-off experiments, to be dependent on transcriptional activation of the gene. LPS did not appreciably affect the hsp70 mRNA half-life. Monocytes exposed to inactivated streptococci, phorbol-12- myristate-13-acetate, and tumor necrosis factor showed augmented levels of hsp70 transcripts, whereas interferon-gamma and monocyte, granulocyte, and granulocyte-monocyte colony-stimulating factors had no effect. Adherence to plastic augmented hsp70 expression in monocytes. S1 protection analysis indicated that the gene expressed in monocytes is indeed a heat-inducible member of the hsp70 gene family rather than a constitutively expressed heat-shock cognate gene. Western blot analysis showed that a heat-inducible HSP72 was present in monocytes and, at augmented levels, in LPS-treated monocytes. LPS-activated monocytes were more resistant to heat shock than unstimulated cells. These data indicate that a heat-inducible hsp70 gene can be efficiently expressed in myelomonocytic cells at physiologic temperatures. Expression of hsp70 genes in monocytes suggests a possible role of heat- inducible genes in the differentiation and/or functional activation of terminally differentiated nonproliferating elements of the myelomonocytic lineage.

scholarly journals Expression of a heat-inducible gene of the HSP70 family in human myelomonocytic cells: regulation by bacterial products and cytokines

Blood ◽  
1991 ◽  
Vol 77 (3) ◽  
pp. 579-586 ◽  
Author(s):  
G Fincato ◽  
N Polentarutti ◽  
A Sica ◽  
A Mantovani ◽  
F Colotta
Keyword(s):  
Heat Shock ◽  
Transcriptional Activation ◽  
Blot Analysis ◽  
Human Peripheral Blood ◽  
Hsp70 Expression ◽  
Hsp70 Gene ◽  
Blood Leukocytes ◽  
Hsp70 Mrna ◽  
Hsp70 Family ◽  
Myelomonocytic Cells

Abstract In this study we have examined the expression of a heat-shock protein (HSP) 70 gene in normal human peripheral blood leukocytes. Northern blot analysis showed that appreciable levels of hsp70 mRNA are present in monocytes and granulocytes, whereas transcript levels were barely detectable or absent in lymphocytes. Monocytes functionally activated by bacterial lipopolysaccharide (LPS) showed an early (15 minutes) increase of hsp70 transcripts that was shown, by actinomycin D blocking and nuclear run-off experiments, to be dependent on transcriptional activation of the gene. LPS did not appreciably affect the hsp70 mRNA half-life. Monocytes exposed to inactivated streptococci, phorbol-12- myristate-13-acetate, and tumor necrosis factor showed augmented levels of hsp70 transcripts, whereas interferon-gamma and monocyte, granulocyte, and granulocyte-monocyte colony-stimulating factors had no effect. Adherence to plastic augmented hsp70 expression in monocytes. S1 protection analysis indicated that the gene expressed in monocytes is indeed a heat-inducible member of the hsp70 gene family rather than a constitutively expressed heat-shock cognate gene. Western blot analysis showed that a heat-inducible HSP72 was present in monocytes and, at augmented levels, in LPS-treated monocytes. LPS-activated monocytes were more resistant to heat shock than unstimulated cells. These data indicate that a heat-inducible hsp70 gene can be efficiently expressed in myelomonocytic cells at physiologic temperatures. Expression of hsp70 genes in monocytes suggests a possible role of heat- inducible genes in the differentiation and/or functional activation of terminally differentiated nonproliferating elements of the myelomonocytic lineage.

scholarly journals Induction of HSP70 gene expression by the antiproliferative prostaglandin PGA2: a growth-dependent response mediated by activation of heat shock transcription factor.

1992 ◽  
Vol 12 (4) ◽  
pp. 1528-1534 ◽  
Author(s):  
N J Holbrook ◽  
S G Carlson ◽  
A M Choi ◽  
J Fargnoli
Keyword(s):  
Heat Shock ◽  
Stress Proteins ◽  
Heat Shock Factor ◽  
Hsp70 Expression ◽  
Hsp70 Gene ◽  
Hsp70 Mrna ◽  
Antiproliferative Effects ◽  
Growth State ◽  
Hsp70 Family ◽  
High Level

Prostaglandins (PG) of the A series are potent inhibitors of cell proliferation. Recently, it was shown that PGA2-induced growth arrest was associated with the increased synthesis of stress proteins encoded by the HSP70 gene family. In this study, we have examined the molecular basis for this increases HSP70 expression. Northern (RNA) blot analysis and nuclear run-on assays demonstrated that induction of high levels of HSP70 mRNA results from an increase in the rate of transcription. High-level induction is specific to the HSP70 family of heat shock proteins and is rapid, reversible, dose dependent, and specific for PGs capable of growth-arresting HeLa cells. In addition, the response was found to be highly dependent on the growth state of the cells, as induction occurs in growing but not in confluent nongrowing cell populations. Induction is dependent on the activation of heat shock factor. Cycloheximide pretreatment, which inhibits the antiproliferative effects of PGA2, prevents activation of the heat shock factor and induction of HSP70 mRNA by PGA2. These results support a role for HSP70 in mediating the antiproliferative effects of PGA2.

Exercise-mediated regulation of Hsp70 expression following aerobic exercise training

2007 ◽  
Vol 293 (6) ◽  
pp. H3692-H3698 ◽  
Author(s):  
C. W. James Melling ◽  
David B. Thorp ◽  
Kevin J. Milne ◽  
Matthew P. Krause ◽  
Earl G. Noble
Keyword(s):  
Gene Expression ◽  
Heat Shock ◽  
Exercise Training ◽  
Transcriptional Activation ◽  
Acute Exercise ◽  
Aerobic Exercise Training ◽  
Exercise Stress ◽  
Hsp70 Expression ◽  
Hsp70 Gene ◽  
Hsp70 Mrna

An issue central to understanding the biological benefits associated with regular exercise training is to elucidate the intracellular mechanisms governing exercise-conferred cardioprotection. Heat shock proteins (HSPs), most notably the inducible 70-kDa HSP family member Hsp70, are believed to participate in the protection of the myocardium during cardiovascular stress. Following acute exercise, activation of PKA mediates the suppression of an intermediary protein kinase, ERK1/2, which phosphorylates and suppresses the activation of the heat shock transcription factor 1 (HSF1). However, following exercise training, ERK1/2 has been reported to regulate the transcriptional activation of several genes involved in cell growth and proliferation and has been shown to be associated with training-mediated myocardial hypertrophy. The present project examined the transcriptional activation of hsp70 gene expression in acutely exercised (60 min at 30 m/min) naïve sedentary and aerobically trained (8 wk, low intensity) male Sprague-Dawley rats. Following acute exercise stress, no significant differences were demonstrated in the expression of myocardial Hsp70 mRNA and activation of PKA between sedentary and trained animals. However, trained animals elicited expression of the hsp70 gene ( P < 0.05) in the presence of elevated ERK1/2 activation. Given the association of ERK1/2 and the suppression of hsp70 gene expression following acute exercise in naïve sedentary rats, these results suggest that training results in adaptations that allow for the simultaneous initiation of both proliferative and protective responses. While it is unclear what factors are associated with this training-related shift, increases in HSF1 DNA binding affinity ( P < 0.05) and posttranscriptional modifications of the Hsp70 transcript are suggested.

Induction of HSP70 gene expression by the antiproliferative prostaglandin PGA2: a growth-dependent response mediated by activation of heat shock transcription factor

1992 ◽  
Vol 12 (4) ◽  
pp. 1528-1534
Author(s):  
N J Holbrook ◽  
S G Carlson ◽  
A M Choi ◽  
J Fargnoli
Keyword(s):  
Heat Shock ◽  
Stress Proteins ◽  
Heat Shock Factor ◽  
Hsp70 Expression ◽  
Hsp70 Gene ◽  
Hsp70 Mrna ◽  
Antiproliferative Effects ◽  
Growth State ◽  
Hsp70 Family ◽  
High Level

Prostaglandins (PG) of the A series are potent inhibitors of cell proliferation. Recently, it was shown that PGA2-induced growth arrest was associated with the increased synthesis of stress proteins encoded by the HSP70 gene family. In this study, we have examined the molecular basis for this increases HSP70 expression. Northern (RNA) blot analysis and nuclear run-on assays demonstrated that induction of high levels of HSP70 mRNA results from an increase in the rate of transcription. High-level induction is specific to the HSP70 family of heat shock proteins and is rapid, reversible, dose dependent, and specific for PGs capable of growth-arresting HeLa cells. In addition, the response was found to be highly dependent on the growth state of the cells, as induction occurs in growing but not in confluent nongrowing cell populations. Induction is dependent on the activation of heat shock factor. Cycloheximide pretreatment, which inhibits the antiproliferative effects of PGA2, prevents activation of the heat shock factor and induction of HSP70 mRNA by PGA2. These results support a role for HSP70 in mediating the antiproliferative effects of PGA2.

Schistosome extracts with heat shock factor activity revealed by the gel shift assay

Parasitology ◽  
1994 ◽  
Vol 108 (1) ◽  
pp. 35-42 ◽  
Author(s):  
R. Levy-Holtzman ◽  
I. Schechter
Keyword(s):  
Heat Shock ◽  
Transcriptional Activation ◽  
Developmental Stages ◽  
Consensus Sequence ◽  
Structural Features ◽  
Heat Shock Factor ◽  
Regulatory Function ◽  
Hsp70 Gene ◽  
Mobility Shift ◽  
Hsp70 Mrna

SUMMARYTo understand the regulated expression of stage-specific genes of schistosomes, it is necessary to identify regulatory DNA elements and DNA-binding proteins that control the level of gene transcription. Here we describe the preparation of Schistosoma mansoni extracts with active transcription factors detected by the electrophoretic mobility shift assay (EMSA). We analysed the hsp70 system of S. mansoni because the promoters of the hsp70 gene contain two heat shock elements (HSE) that differ from the consensus sequence (CnnGAAnnTTCnnG) at one (HSEI) or three (HSEII) positions, and it is known that transcriptional activation of hsp70 genes is mediated by interaction of HSE with the heat shock factor (HSF). Analyses of parasite extracts from different developmental stages demonstrate the presence of putative HSF that correlates with the pattern of hsp70 mRNA expression (cercariae-, schistosomula+, adult worms+). Cercarial extracts did not show binding of 32P-labelled HSEI or HSEII. Extracts of schistosomula and of adult worms kept at 37 or 42 °C showed binding of HSEI but not HSEII. The specificity of HSEI-HSF complex formation was ascertained by inhibition experiments. The EMSA experiments and structural features of the hsp70 promoter indicate that HSEI is the major DNA element responsible for transcriptional activation of the hsp70 gene, while the HSEII may be a redundant sequence with minor (if any) regulatory function. The extracts reported here can be used to study transcriptional control of other schistosome genes.

scholarly journals Posttranscriptional regulation of hsp70 expression in human cells: effects of heat shock, inhibition of protein synthesis, and adenovirus infection on translation and mRNA stability.

1987 ◽  
Vol 7 (12) ◽  
pp. 4357-4368 ◽  
Author(s):  
N G Theodorakis ◽  
R I Morimoto
Keyword(s):  
Protein Synthesis ◽  
Heat Shock ◽  
Posttranscriptional Regulation ◽  
High Efficiency ◽  
Hsp70 Expression ◽  
Mrna Levels ◽  
Protein Synthesis Inhibitors ◽  
Hsp70 Mrna ◽  
Infected Cells ◽  
The Stability

We have examined the posttranscriptional regulation of hsp70 gene expression in two human cell lines, HeLa and 293 cells, which constitutively express high levels of HSP70. HSP70 mRNA translates with high efficiency in both control and heat-shocked cells. Therefore, heat shock is not required for the efficient translation of HSP70 mRNA. Rather, the main effect of heat shock on translation is to suppress the translatability of non-heat shock mRNAs. Heat shock, however, has a marked effect on the stability of HSP70 mRNA; in non-heat-shocked cells the half-life of HSP70 mRNA is approximately 50 min, and its stability increases at least 10-fold upon heat shock. Moreover, HSP70 mRNA is more stable in cells treated with protein synthesis inhibitors, suggesting that a heat shock-sensitive labile protein regulates its turnover. An additional effect on posttranscriptional regulation of hsp70 expression can be found in adenovirus-infected cells, in which HSP70 mRNA levels decline precipititously late during infection although hsp70 transcription continues unabated.

Preferential deadenylation of Hsp70 mRNA plays a key role in regulating Hsp70 expression in Drosophila melanogaster

1994 ◽  
Vol 14 (6) ◽  
pp. 3646-3659
Author(s):  
R P Dellavalle ◽  
R Petersen ◽  
S Lindquist
Keyword(s):  
Drosophila Melanogaster ◽  
Heat Shock ◽  
Rna Processing ◽  
Hsp70 Expression ◽  
Hsp70 Mrna ◽  
Mild Heat ◽  
Endonucleolytic Cleavage ◽  
Heat Shocks ◽  
Low Efficiency ◽  
Hsp70 Synthesis

Following a standard heat shock, approximately 40% of Hsp70 transcripts in Drosophila melanogaster lack a poly(A) tail. Since heat shock disrupts other aspects of RNA processing, this observation suggested that heat might disrupt polyadenylation as well. We find, however, that as the temperature is increased a larger fraction of Hsp70 RNA is polyadenylated. Poly(A)-deficient Hsp70 RNAs arise not from a failure in polyadenylation but from the rapid and selective removal of poly(A) from previously adenylated transcripts. Poly(A) removal is highly regulated: poly(A) is (i) removed much more rapidly from Hsp70 RNAs than from Hsp23 RNAs, (ii) removed more rapidly after mild heat shocks than after severe heat shocks, and (iii) removed more rapidly after a severe heat shock if cells have first been conditioned by a mild heat treatment. Poly(A) seems to be removed by simple deadenylation rather than by endonucleolytic cleavage 5' of the adenylation site. During recovery from heat shock, deadenylation is rapidly followed by degradation. In cells maintained at high temperatures, however, the two processes are uncoupled and Hsp70 RNAs are deadenylated without being degraded. These deadenylated mRNAs are translated with low efficiency. Deadenylation therefore allows Hsp70 synthesis to be repressed even when degradation of the mRNA is blocked. Poly(A) tail shortening appears to play a key role in regulating Hsp70 expression.

Regulation of HSP70 by PTH: a model of gene regulation not mediated by changes in cAMP levels

1996 ◽  
Vol 271 (1) ◽  
pp. C121-C129 ◽  
Author(s):  
S. Fukayama ◽  
B. Lanske ◽  
J. Guo ◽  
H. M. Kronenberg ◽  
F. R. Bringhurst
Keyword(s):  
Heat Shock ◽  
Adenylate Cyclase ◽  
Gene Transcription ◽  
Cellular Response ◽  
Host Cells ◽  
Osteoblastic Cell ◽  
Target Cells ◽  
Hsp70 Gene ◽  
Hsp70 Mrna ◽  
Human Hsp70

Parathyroid hormone (PTH) activates both adenylate cyclase and phospholipase C in target cells, and cloned PTH/PTH-related protein (PTHrP) receptor can mediate both responses when expressed in host cells such as LLC-PK1 renal epithelial cells. Because calcitonin (CT) is known to augment 70-kDa heat shock protein (HSP70) mRNA by an adenosine 3',5'-cyclic monophosphate (cAMP)-independent mechanism in LLC-PK1 cells, we examined regulation of HSP70 transcription by PTH in these cells. Like CT, human PTH-(1-34) [hPTH-(1-34); 10(-10) to 10(-7) M)] increased porcine HSP70 mRNA and human HSP70 promoter-chloramphenicol acetyltransferase (CAT) expression within 4 h in LLC-PK1 cells that stably express > or = 100,000 PTH/PTHrP receptors per cell. The effect of PTH on HSP70 mRNA was not mimicked by cAMP analogues, forskolin, phorbol esters, Ca2+ ionophores, or alpha-thrombin; was insensitive to pertussis toxin; and was not due to increased mRNA stability. The upregulation of HSP70 gene transcription by hPTH (and CT) was clearly observed even after deletion of the functional heat shock consensus element in the promoter region of the human HSP70/CAT reporter. Upregulation of HSP70 transcription via endogenous PTH receptors also was observed in the osteoblastic cell lines SaOS-2 and ROS 17/2.8. Regulation of HSP70 gene transcription by PTH may be a common cellular response to the hormone, which, in some cells, may not be mediated by activation of adenylate cyclase or protein kinase C.

scholarly journals Regulation of heat shock protein synthesis by quercetin in human erythroleukaemia cells

1994 ◽  
Vol 300 (1) ◽  
pp. 201-209 ◽  
Author(s):  
G Elia ◽  
M G Santoro
Keyword(s):  
Heat Shock ◽  
Mammalian Cells ◽  
Elevated Temperatures ◽  
K562 Cells ◽  
Hsp70 Expression ◽  
Transcriptional Level ◽  
Hsp70 Mrna ◽  
Shock Proteins ◽  
Hsp70 Synthesis

Synthesis of heat-shock proteins (HSPs) is universally induced in eukaryotic and prokaryotic cells by exposure to elevated temperatures or to other types of environmental stress. In mammalian cells, HSPs belonging to the 70 kDa family (HSP70) have a regulatory role in several cellular processes, and have been shown to be involved in the control of cell proliferation and differentiation. Although many types of HSP70 inducers have been identified, only a few compounds, all belonging to the flavonoid group, have been shown to inhibit HSP70 induction. Because inhibitors of HSP70 synthesis could be an important tool with which to study the function of this protein, we have investigated the effect of quercetin, a flavonoid with antiproliferative activity which is widely distributed in nature, on HSP70 synthesis in human K562 erythroleukaemia cells after treatment with severe or mild heat shock and with other inducers. Quercetin was found to affect HSP70 synthesis at more than one level, depending on the conditions used. Indeed, after severe heat shock (45 degrees C for 20 min) treatment with quercetin, at non-toxic concentrations, was found to inhibit HSP70 synthesis for a period of 3-4 h. This block appeared to be exerted at the post-transcriptional level and to be cell-mediated, as the addition of quercetin during translation of HSP70 mRNA in vitro had no effect. After prolonged (90 min) exposure at 43 degrees C, however, quercetin was found to inhibit also HSP70 mRNA transcription. Pretreatment of K562 cells with quercetin had no effect on HSP70 expression, and quercetin needed to be present during induction to be effective. Under all conditions tested, the quercetin-induced block of HSP70 synthesis was found to be transient and, after an initial delay, synthesis of HSP70 reached the control rate and continued at the same level for several hours after the time at which HSP70 synthesis had been turned off in control cells. Finally, inhibition of HSP70 synthesis by quercetin appeared to be dependent on the temperature used and on the type of stressor.

Exogenous heat shock protein-70 inhibits cigarette smoke-induced intimal thickening

2008 ◽  
Vol 295 (4) ◽  
pp. R1320-R1327 ◽  
Author(s):  
Michiaki Matsumoto ◽  
Paul C. Dimayuga ◽  
Charles Wang ◽  
Jonathan Kirzner ◽  
Miha Cercek ◽  
...  
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Cigarette Smoke ◽  
Heat Shock Protein 70 ◽  
Nuclear Antigen ◽  
Cigarette Smoke Exposure ◽  
Hsp70 Expression ◽  
Intimal Thickening ◽  
Hsp70 Mrna ◽  
Recombinant Hsp70

Cigarette smoke is associated with increased carotid intimal thickening or stroke. Preliminary work showed that exposure to smoke resulted in a 4.5-fold reduction of heat shock protein-70 (HSP70) expression in spleens of mice using gene microarray analysis. In the current study, we investigated the role of extracellular HSP70 in carotid intimal thickening of mice exposed to cigarette smoke. Intimal thickening was induced by placement of a cuff around the right carotid artery of mice. Cuff injury resulted in increased HSP70 mRNA expression in carotid arteries that persisted for 21 days. Cigarette smoke exposure decreased arterial HSP70 expression and significantly increased intimal thickening compared with mice exposed to air. Treatment of mice exposed to cigarette smoke with intravenous recombinant HSP70 attenuated intimal thickening through reduced phosphorylated extracellular signal-regulated kinase (pERK) expression in the arterial wall. In vitro experiments with rat aortic smooth muscle cells confirmed that recombinant HSP70 decreases pERK and proliferating cell nuclear antigen (PCNA) expression in cells exposed to cigarette smoke extract and H2O2. Our study suggests that decreased expression of arterial HSP70 is an important mechanism by which exposure to cigarette smoke augments intimal thickening. The effects of recombinant HSP70 suggest a role for extracellular HSP70.

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