Heat shock response of thermophilic fungi: membrane lipids and soluble carbohydrates under elevated temperatures

Elena A. Ianutsevich; Olga A. Danilova; Natalia V. Groza; Ekaterina R. Kotlova; Vera M. Tereshina

doi:10.1099/mic.0.000279

Mitochondrial activity and heat-shock response during morphogenesis in the pathogenic fungus Histoplasma capsulatum

Biochemistry and Cell Biology ◽

10.1139/o92-031 ◽

1992 ◽

Vol 70 (3-4) ◽

pp. 207-214 ◽

Cited By ~ 17

Author(s):

Eduardo J. Patriarca ◽

George S. Kobayashi ◽

Bruno Maresca

Keyword(s):

Heat Shock ◽

Heat Shock Response ◽

Elevated Temperatures ◽

Histoplasma Capsulatum ◽

Pathogenic Fungus ◽

Temperature Shift ◽

Mitochondrial Activity ◽

Mitochondrial Atpase ◽

Heat Shock Genes ◽

Shock Response

Changes in temperature and a variety of other stimuli coordinately induce transcription of a specific set of heat-shock genes in all organisms. In the human fungal pathogen Histoplasma capsulatum, a temperature shift from 25 to 37 °C acts not only as a signal that causes transcription of heat-shock genes, but also triggers a morphological mycelium-to yeast-phase transition. The temperature-induced morphological transition may be viewed as a heat-shock response followed by cellular adaptation to a higher temperature. We have found that by inducing thermotolerance, i.e., an initial incubation at 34 °C, the thermosensitive attenuated Downs strain of H. capsulatum can be made to resemble those of the more temperature-tolerant G222B strain with respect to mitochondrial ATPase activity and electron transport efficiency at elevated temperatures. Furthermore, if the heat-shock response is first elicited by preincubation at milder temperatures or stress, transcription of heat-shock mRNA in mycelial cells of Downs strain that shifted to 37 °C proceeds at rates comparable to those of the virulent strains.Key words: heat shock, thermotolerance, ATPase, 70-kilodalton heat-shock protein, fungal morphogenesis.

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Molecular Basis of the Defective Heat Stress Response in Mycobacterium leprae

Journal of Bacteriology ◽

10.1128/jb.00601-07 ◽

2007 ◽

Vol 189 (24) ◽

pp. 8818-8827 ◽

Cited By ~ 15

Author(s):

Diana L. Williams ◽

Tana L. Pittman ◽

Mike Deshotel ◽

Sandra Oby-Robinson ◽

Issar Smith ◽

...

Keyword(s):

Heat Stress ◽

Stress Response ◽

Heat Shock ◽

Heat Shock Response ◽

Elevated Temperatures ◽

Transcriptional Response ◽

Mycobacterium Leprae ◽

Heat Stress Response ◽

Regulatory Circuits ◽

Shock Response

ABSTRACT Mycobacterium leprae, a major human pathogen, grows poorly at 37°C. The basis for its inability to survive at elevated temperatures was investigated. We determined that M. leprae lacks a protective heat shock response as a result of the lack of transcriptional induction of the alternative sigma factor genes sigE and sigB and the major heat shock operons, HSP70 and HSP60, even though heat shock promoters and regulatory circuits for these genes appear to be intact. M. leprae sigE was found to be capable of complementing the defective heat shock response of mycobacterial sigE knockout mutants only in the presence of a functional mycobacterial sigH, which orchestrates the mycobacterial heat shock response. Since the sigH of M. leprae is a pseudogene, these data support the conclusion that a key aspect of the defective heat shock response in M. leprae is the absence of a functional sigH. In addition, 68% of the genes induced during heat shock in M. tuberculosis were shown to be either absent from the M. leprae genome or were present as pseudogenes. Among these is the hsp/acr2 gene, whose product is essential for M. tuberculosis survival during heat shock. Taken together, these results suggest that the reduced ability of M. leprae to survive at elevated temperatures results from the lack of a functional transcriptional response to heat shock and the absence of a full repertoire of heat stress response genes, including sigH.

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Influence of temperature on the development, reproduction and regeneration in the flatworm model organism Macrostomum lignano

10.1101/389478 ◽

2018 ◽

Cited By ~ 1

Author(s):

Jakub Wudarski ◽

Kirill Ustyantsev ◽

Lisa Glazenburg ◽

Eugene Berezikov

Keyword(s):

Heat Shock ◽

Heat Shock Response ◽

Elevated Temperatures ◽

Model Organism ◽

Response Threshold ◽

Reproduction Rate ◽

Negative Consequences ◽

Time Reproduction ◽

Shock Response ◽

Macrostomum Lignano

AbstractThe free-living marine flatworm Macrostomum lignano is a powerful model organism to study mechanisms of regeneration and stem cell regulation due to its convenient combination of biological and experimental properties, including the availability of transgenesis methods, which is unique among flatworm models. However, due to its relatively recent introduction in research, there are still many biological aspects of the animal that are not known. One of such questions is the influence of the culturing temperature on Macrostomum biology. Here we systematically investigated how different culturing temperatures affect the development time, reproduction rate, regeneration, heat shock response, and gene knockdown efficiency by RNA interference in M. lignano. We used marker transgenic lines of the flatworm to accurately measure the regeneration endpoint and to establish the stress response threshold for temperature shock. We found that compared to the culturing temperature of 20°C commonly used for M. lignano, elevated temperatures of 25°C-30°C substantially speed-up the development and regeneration time and increase reproduction rate without detectable negative consequences for the animal, while temperatures above 30°C elicit a heat shock response.We show that altering the temperature conditions can be used to shorten the time required to establish M. lignano cultures, store important lines and optimize the microinjection procedures for transgenesis. Our findings will help to optimize the design of experiments in M. lignano and thus facilitate future research in this model organism.

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Conventional and novel PKC isoenzymes modify the heat-induced stress response but are not activated by heat shock

Journal of Cell Science ◽

10.1242/jcs.111.22.3357 ◽

1998 ◽

Vol 111 (22) ◽

pp. 3357-3365 ◽

Cited By ~ 1

Author(s):

C.I. Holmberg ◽

P.M. Roos ◽

J.M. Lord ◽

J.E. Eriksson ◽

L. Sistonen

Keyword(s):

Stress Response ◽

Heat Shock ◽

Heat Shock Response ◽

Mammalian Cells ◽

Elevated Temperatures ◽

Heat Shock Element ◽

Post Translational Modifications ◽

Induced Stress ◽

Shock Response

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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