Heat shock gene expression in Xenopus laevis A6 cells in response to heat shock and sodium arsenite treatments

1988 ◽  
Vol 66 (8) ◽  
pp. 862-870 ◽  
Author(s):  
S. Darasch ◽  
D. D. Mosser ◽  
N. C. Bols ◽  
J. J. Heikkila
Keyword(s):  
Heat Shock ◽  
Xenopus Laevis ◽  
Sodium Arsenite ◽  
Polyacrylamide Gel Electrophoresis ◽  
Heat Shock Gene ◽  
Epithelial Cell Line ◽  
Continuous Exposure ◽  
Mrna Levels ◽  
Hsp 70 ◽  
Mrna Accumulation

Continuous exposure of a Xenopus laevis kidney epithelial cell line, A6, to either heat shock (33 °C) or sodium arsenite (50 μM) resulted in transient but markedly different temporal patterns of heat-shock protein (HSP) synthesis and HSP 70 and 30 mRNA accumulation. Heat-shock-induced synthesis of HSPs was detectable within 1 h and reached maximum levels by 2–3 h. While sodium arsenite induced the synthesis of some HSPs within 1 h, maximal HSP synthesis did not occur until 12 h. The pattern of HSP 70 and 30 mRNA accumulation was similar to the response observed at the protein level. During recovery from heat shock, a coordinate decline in HSPs and HSP 70 and 30 mRNA was observed. During recovery from sodium arsenite, a similar phenomenon occurred during the initial stages. However, after 6 h of recovery, HSP 70 mRNA levels persisted in contrast to the declining HSP 30 mRNA levels. Two-dimensional polyacrylamide gel electrophoresis revealed the presence of 5 HSPs in the HSP 70 family, of which two were constitutive, and 16 different stress-inducible proteins in the HSP 30 family. In conclusion, heat shock and sodium arsenite induce a similar set of HSPs but maximum synthesis of the HSP is temporally separated by 12–24 h.

Heat and sodium arsenite act synergistically on the induction of heat shock gene expression in Xenopus laevis A6 cells

1987 ◽  
Vol 65 (4) ◽  
pp. 310-316 ◽  
Author(s):  
J. J. Heikkila ◽  
S. P. Darasch ◽  
D. D. Mosser ◽  
N. C. Bols
Keyword(s):  
Heat Shock ◽  
Sodium Arsenite ◽  
Heat Shock Gene ◽  
Northern Hybridization ◽  
Epithelial Cell Line ◽  
Hsp 70 ◽  
Dot Blot ◽  
Mrna Accumulation ◽  
A6 Cells ◽  
Heat Shock Gene Expression

Heat shock protein (HSP) synthesis was studied in the Xenopus epithelial cell line A6 in response to heat and sodium arsenite, either singly or together. Temperatures of 33–35 °C consistently brought about the synthesis of HSPs at 87,73,70,54,31, and 30 kilodaltons (kDa), whereas sodium arsenite at 25–100 μM induced the synthesis of HSPs at 73 and 70 kDa. In cultures exposed to 10 μM sodium arsenite at 30 °C, HSP synthesis in the 68- to 73-kDa and 29- to 31-kDa regions was much greater than the HSP synthesis in response to each treatment individually. RNA dot blot analysis using homologous genomic subclones revealed that heat shock induced the accumulation of HSP 70 and 30 mRN As. The sizes of the HSP 70 and 30 mRN As determined by Northern hybridization were 2.7 and 1.5 kilobases, respectively. Sodium arsenite (10–100 μM) also induced the accumulation of both HSP 70 and 30 mRNAs. Finally, a mild heat shock (30 °C) plus a low concentration of sodium arsenite (10 μM) acted synergistically on HSP 70 and 30 mRN A accumulation in A6 cells. Thus sodium arsenite and heat act synergistically at the level of both HSP synthesis and HSP mRNA accumulation.

Examination of heat shock protein mRNA accumulation in early Xenopus laevis embryos

1987 ◽  
Vol 65 (2) ◽  
pp. 87-94 ◽  
Author(s):  
J. J. Heikkila ◽  
N. Ovsenek ◽  
P. Krone
Keyword(s):  
Heat Shock ◽  
Xenopus Laevis ◽  
Heat Shock Protein ◽  
Incubation Temperature ◽  
Effect Of Temperature ◽  
Continuous Exposure ◽  
Hsp 70 ◽  
Mrna Accumulation ◽  
Mrna Induction ◽  
Xenopus Laevis Embryos

Elevation of the incubation temperature of Xenopus laevis neurulae from 22 to 33–35 °C induced the accumulation of heat shock protein (hsp) 70 mRNA (2.7 kilobases (kb)) and a putative hsp 87 mRNA (3.2 kb). While constitutive levels of both hsp mRNAs were detectable in unfertilized eggs and cleavage-stage embryos, heat-induced accumulation was not observed until after the mid-blastula stage. Exposure of Xenopus laevis embryos to other stressors, such as sodium arsenite or ethanol, also induced a developmental stage-dependent accumulation of hsp 70 mRNA. To characterize the effect of temperature on hsp 70 mRNA induction, neurulae were exposed to a range of temperatures (27–37 °C) for 1 h. Heat-induced hsp 70 mRNA accumulation was first detectable at 27 °C, with relatively greater levels at 30–35 °C and lower levels at 37 °C. A more complex effect of temperature on hsp 70 mRNA accumulation was observed in a series of time course experiments. While continuous exposure of neurulae to heat shock (27–35 °C) induced a transient accumulation of hsp 70 mRNA, the temporal pattern of hsp 70 mRNA accumulation was temperature dependent. Exposure of embryos to 33–35 °C induced maximum relative levels of hsp 70 mRNA within 1–1.5 h, while at 30 and 27 °C peak hsp 70 mRNA accumulation occurred at 3 and 12 h, respectively. Finally, placement of Xenopus neurulae at 22 °C after a 1-h heat shock at 33 °C produced an initial decrease in hsp 70 mRNA within 15–30 min, followed by a transient increase in hsp 70 mRNA at 1–2 h before decaying to background levels by 7 h.

Expression of heat shock genes of Neurospora crassa: effect of hyperthermia and other stresses on mRNA levels

1988 ◽  
Vol 66 (2) ◽  
pp. 81-92 ◽  
Author(s):  
Carol A. Curle ◽  
M. Kapoor
Keyword(s):  
Heat Shock ◽  
Neurospora Crassa ◽  
Sodium Arsenite ◽  
Gene Probe ◽  
Mrna Levels ◽  
Hsp 70 ◽  
Northern Blots ◽  
Stressed Cells ◽  
Shock Proteins

Neurospora crassa mycelium was heat shocked for intervals varying from 15–180 min. Heat shock mRNA was monitored by hybridization of Northern blots with the Drosophila hsp-70 gene probe and an inducible member of the yeast hsp-70 gene family, YG100. A 2.7 kilobase (kb) transcript, with homology to these two probes, was detected in cultures shocked for 15 min; its levels increased up to 60–90 min and declined thereafter. Sodium arsenite, too, induced the synthesis of this transcript. An additional, constitutively synthesized 2.4-kb transcript was revealed by hybridization with the yeast probe. The synthesis of this message was terminated during heat shock. Hybridization of Northern blots with the Drosophila actin gene probe demonstrated two size classes, 1.85 and 1.63 kb; the former decreased dramatically following heat shock. Recovery, as assessed by the disappearance of the 2.7-kb hsp-70-mRNA and restoration of the 1.85-kb actin message to the prestress levels, was essentially complete within 60 min of transfer to 28 °C. In vitro translations of RNA from stressed cells showed the heat shock messages to be stable and readily translatable. RNA of cells subjected to heat shock plus CdCl2 showed a higher content of messages for heat shock proteins of 70, 80, and 90 kilodaltons.

Effects of cycloheximide on thermotolerance expression, heat shock protein synthesis, and heat shock protein mRNA accumulation in rat fibroblasts

1986 ◽  
Vol 6 (4) ◽  
pp. 1088-1094
Author(s):  
R B Widelitz ◽  
B E Magun ◽  
E W Gerner
Keyword(s):  
Protein Synthesis ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
Mrna Levels ◽  
Hsp 70 ◽  
Mrna Accumulation ◽  
General Protein Synthesis ◽  
Rat Fibroblasts ◽  
General Protein ◽  
Rat Embryonic Fibroblasts

A single hyperthermic exposure can render cells transiently resistant to subsequent high temperature stresses. Treatment of rat embryonic fibroblasts with cycloheximide for 6 h after a 20-min interval at 45 degrees C inhibits protein synthesis, including heat shock protein (hsp) synthesis, and results in an accumulation of hsp 70 mRNA, but has no effect on subsequent survival responses to 45 degrees C hyperthermia. hsp 70 mRNA levels decreased within 1 h after removal of cycloheximide but then appeared to stabilize during the next 2 h (3 h after drug removal and 9 h after heat shock). hsp 70 mRNA accumulation could be further increased by a second heat shock at 45 degrees C for 20 min 6 h after the first hyperthermic exposure in cycloheximide-treated cells. Both normal protein and hsp synthesis appeared increased during the 6-h interval after hyperthermia in cultures which received two exposures to 45 degrees C for 20 min compared with those which received only one treatment. No increased hsp synthesis was observed in cultures treated with cycloheximide, even though hsp 70 mRNA levels appeared elevated. These data indicate that, although heat shock induces the accumulation of hsp 70 mRNA in both normal and thermotolerant cells, neither general protein synthesis nor hsp synthesis is required during the interval between two hyperthermic stresses for Rat-1 cells to express either thermotolerance (survival resistance) or resistance to heat shock-induced inhibition of protein synthesis.

scholarly journals Effects of cycloheximide on thermotolerance expression, heat shock protein synthesis, and heat shock protein mRNA accumulation in rat fibroblasts.

1986 ◽  
Vol 6 (4) ◽  
pp. 1088-1094 ◽  
Author(s):  
R B Widelitz ◽  
B E Magun ◽  
E W Gerner
Keyword(s):  
Protein Synthesis ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
Mrna Levels ◽  
Hsp 70 ◽  
Mrna Accumulation ◽  
General Protein Synthesis ◽  
Rat Fibroblasts ◽  
General Protein ◽  
Rat Embryonic Fibroblasts

A single hyperthermic exposure can render cells transiently resistant to subsequent high temperature stresses. Treatment of rat embryonic fibroblasts with cycloheximide for 6 h after a 20-min interval at 45 degrees C inhibits protein synthesis, including heat shock protein (hsp) synthesis, and results in an accumulation of hsp 70 mRNA, but has no effect on subsequent survival responses to 45 degrees C hyperthermia. hsp 70 mRNA levels decreased within 1 h after removal of cycloheximide but then appeared to stabilize during the next 2 h (3 h after drug removal and 9 h after heat shock). hsp 70 mRNA accumulation could be further increased by a second heat shock at 45 degrees C for 20 min 6 h after the first hyperthermic exposure in cycloheximide-treated cells. Both normal protein and hsp synthesis appeared increased during the 6-h interval after hyperthermia in cultures which received two exposures to 45 degrees C for 20 min compared with those which received only one treatment. No increased hsp synthesis was observed in cultures treated with cycloheximide, even though hsp 70 mRNA levels appeared elevated. These data indicate that, although heat shock induces the accumulation of hsp 70 mRNA in both normal and thermotolerant cells, neither general protein synthesis nor hsp synthesis is required during the interval between two hyperthermic stresses for Rat-1 cells to express either thermotolerance (survival resistance) or resistance to heat shock-induced inhibition of protein synthesis.

Analysis of hsp 30, hsp 70 and ubiquitin gene expression in Xenopus laevis tadpoles

Development ◽  
1988 ◽  
Vol 103 (1) ◽  
pp. 59-67
Author(s):  
P.H. Krone ◽  
J.J. Heikkila
Keyword(s):  
Heat Shock ◽  
Xenopus Laevis ◽  
Temporal Pattern ◽  
Size Range ◽  
Continuous Exposure ◽  
Hsp 70 ◽  
Blastula Stage ◽  
Tailbud Stage ◽  
Actin Mrna ◽  
Continuous Heat

Heat-induced accumulation of hsp 30 mRNA (1.1 kb) during early development of Xenopus laevis was first detectable at the tailbud stage (stage 30–34). This contrasts with heat-induced accumulation of hsp 70 mRNA (2.7 kb) and ubiquitin mRNA (size range = 1.7–3.1 kb), which was first detectable at the mid- to late-blastula stage. Continuous exposure of tadpoles to a 33 degrees C heat shock resulted in a coordinate, transient accumulation of hsp 30, hsp 70 and ubiquitin mRNA. A coordinate, temporal pattern was also observed for the decay of hsp 30, hsp 70 and ubiquitin mRNA in tadpoles recovering at 22 degrees C following a 1 h heat shock at 33 degrees C. Thus, while hsp 30 genes are regulated differently during development compared with hsp 70 and ubiquitin genes, these genes all exhibit a coordinate heat-inducible pattern of expression at the tadpole stage. Levels of alpha-cardiac actin mRNA remained unchanged during continuous heat shock and recovery experiments.

scholarly journals Three light-inducible heat shock genes of Chlamydomonas reinhardtii.

1989 ◽  
Vol 9 (9) ◽  
pp. 3911-3918 ◽  
Author(s):  
E D von Gromoff ◽  
U Treier ◽  
C F Beck
Keyword(s):  
Thermal Stress ◽  
Elevated Temperature ◽  
Heat Shock ◽  
Chlamydomonas Reinhardtii ◽  
Heat Shock Gene ◽  
Mrna Levels ◽  
Heat Shock Genes ◽  
Drastic Increase ◽  
Shock Gene

Genomic clones representing three Chlamydomonas reinhardtii genes homologous to the Drosophila hsp70 heat shock gene were isolated. The mRNAs of genes hsp68, hsp70, and hsp80 could be translated in vitro into proteins of Mr 68,000, 70,000, and 80,000, respectively. Transcription of these genes increased dramatically upon heat shock, and the corresponding mRNAs rapidly accumulated, reaching a peak at around 30 min after a shift to the elevated temperature. Light also induced the accumulation of the mRNAs encoded by these heat shock genes. A shift of dark-grown cells to light resulted in a drastic increase in mRNA levels, which reached a maximum at around 1 h after the shift. Thus, in Chlamydomonas, expression of hsp70-homologous heat shock genes appears to be regulated by thermal stress and light.

Depressed expression of the inducible form of HSP 70 (HSP 72) in brain and heart after in vivo heat shock

1995 ◽  
Vol 269 (3) ◽  
pp. R608-R613 ◽  
Author(s):  
S. C. Beck ◽  
C. N. Paidas ◽  
H. Tan ◽  
J. Yang ◽  
A. De Maio
Keyword(s):  
Heat Shock ◽  
Cell Types ◽  
Heat Shock Gene ◽  
Hsp 70 ◽  
Shock Gene ◽  
Heat Shock Gene Expression ◽  
Total Body ◽  
Different Levels ◽  
Low Expression

The heat shock gene expression plays a role in the protection of cells from injury. In the present study, we have analyzed the expression of heat shock protein (HSP) 72 (the major inducible form of the HSP 70 family) in different rat organs after a total body hyperthermia. The content of HSP 72 was greatest in liver and colon. In contrast, accumulation of HSP 72 was low in heart and brain (3-5% and < 1% of the amount in liver, respectively). This low expression of HSP 72 in heart and brain could not be explained by a difference in the actual temperature within these organs. Analysis of cells in culture that resemble hepatocytes, myoblast, and neurons showed a pattern of HSP 72 expression similar to that observed in liver, heart, and brain in vivo after heat shock. These results suggest that this disparate expression of HSP 72 is due to intrinsic characteristics of the cell types rather than to physiological or environmental conditions. The differential expression of HSP 72 among different cell lines could be correlated with the different levels of protein synthesis protection.

scholarly journals Heat shock of human synovial and dermal fibroblasts induces delayed up-regulation of collagenase-gene expression

1995 ◽  
Vol 308 (3) ◽  
pp. 743-747 ◽  
Author(s):  
E G Hitraya ◽  
J Varga ◽  
S A Jimenez
Keyword(s):  
Gene Expression ◽  
Heat Shock ◽  
Binding Site ◽  
Transcriptional Activation ◽  
Human Fibroblasts ◽  
Dermal Fibroblasts ◽  
Mrna Levels ◽  
Hsp 70 ◽  
Mobility Shift ◽  
Collagenase Gene

We investigated the effect of heat shock on the expression of the collagenase gene in normal human synovial and dermal fibroblasts. Heat shock (42-44 degrees C for 1 h) caused a marked increase in heat-shock protein 70 (HSP-70) mRNA levels, followed by a delayed increase in collagenase mRNA levels, in both cell types. Pretreatment with cycloheximide had no effect on the heat-shock-induced increase in HSP-70 mRNA expression, but abrogated the induction of collagenase mRNA during the recovery. To study the mechanisms of collagenase-gene induction by heat shock, the transcriptional activity of a collagenase-promoter-driven chloramphenicol acetyltransferase (CAT) reporter gene was examined in transient transfection experiments. Heat shock was followed by a > 2-fold increase in CAT activity driven by a 3.8 kb fragment of the collagenase promoter, or by a construct containing an AP-1 binding site. A mutation in the AP-1 binding site abolished the effect of heat shock. Electrophoretic-mobility-shift assays revealed a marked increase in DNA-binding activity specific for the AP-1 binding site in nuclear extracts prepared from synovial fibroblasts recovering from heat shock. These results indicate that heat shock causes a delayed increase in collagenase-gene expression in human fibroblasts, and suggests that this stimulation involves, at least in part, transcriptional activation through an AP-1 binding site. Heat shock appears to initiate a programme of cellular events resulting in collagenase-gene expression, and therefore may contribute to connective-tissue degradation in disease states.

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