Transcriptional and translational regulation of major heat shock proteins and patterns of trehalose mobilization during hyperthermic recovery in repressed and derepressedSaccharomyces cerevisiae

1998 ◽  
Vol 44 (4) ◽  
pp. 341-350 ◽  
Author(s):  
Claudia Gross ◽  
Kenneth Watson
Keyword(s):  
Heat Stress ◽  
Heat Shock ◽  
Heat Shock Proteins ◽  
Translational Regulation ◽  
De Novo ◽  
Recovery Period ◽  
Recovery Phase ◽  
Heat Shock Gene ◽  
Genes Encoding ◽  
Shock Proteins

Patterns of heat shock gene transcription and translation, as well as trehalose content, were investigated in both glucose (repressed) and acetate (derepressed) grown cells of Saccharomyces cerevisiae during heat shock and subsequent return of cells to 25°C. Heat-shocked cells (37°C for 30 min), grown in either glucose- or acetate-supplemented media, initially acquired high thermotolerance to a 50°C heat stress, which was progressively lost when cultures were allowed to recover at 25°C and subsequently exposed to a second heat stress. In all cases, with the notable exception of repressed cells of a relatively thermosensitive strain, inhibition of protein synthesis and coincident decrease in trehalose accumulation during the heat shock had little effect on the kinetics of loss of thermotolerance. Heat shock at 37°C elicited a marked increase in transcription and translation of genes encoding major heat shock proteins (hsps). During recovery at 25°C, both metabolic activities were suppressed followed by a gradual increase in hsp mRNA transcription to levels observed prior to heat shock. De novo translation of hsp mRNAs, however, was no longer observed during the recovery phase, although immuno- detection analyses demonstrated persistence of high levels of hsps 104, 90, 70, and 60 in cells throughout the 240-min recovery period. In addition, while heat shock induced trehalose was rapidly degraded during recovery in repressed cells, levels remained high in derepressed cells. Results therefore indicated that the progressive loss of induced thermotolerance exhibited by glucose- and acetate-grown cells was not closely correlated with levels of hsp or trehalose. It was concluded that both constitutive and de novo synthesized hsps require heat shock associated activation to confer thermotolerance and this modification is progressively reversed upon release from the heat-shocked state.Key words: thermotolerance, hyperthermic recovery, hsp transcription, hsp translation, trehalose.

The Heat-Shock Response Relevant to Molecular and Structural Changes in Wheat Yield and Quality

1994 ◽  
Vol 21 (6) ◽  
pp. 901 ◽  
Author(s):  
C Blumenthal ◽  
CW Wrigley ◽  
IL Batey ◽  
EWR Barlow
Keyword(s):  
Heat Stress ◽  
Heat Shock ◽  
Heat Shock Proteins ◽  
Structural Changes ◽  
De Novo ◽  
Wheat Yield ◽  
Radioactive Tracer ◽  
Gluten Proteins ◽  
Radioactive Labelling ◽  
Shock Proteins

When wheat coleoptiles or plants are subjected to a period of heat stress (e.g, at > 35�C for 1 h or more), there is a reduction in normal protein synthesis, accompanied by de novo synthesis of the classical range of heat-shock proteins (based on radioactive tracer experiments) in virtually all parts of the plant. Study of coleoptile elongation rates indicates that this synthesis is related to a protective effect, whereby a preliminary heat shock provides a degree of protection against a later lethal shock. This thermotolerance is also associated with the appearance in coleoptiles and roots of a small peptide (detected without radioactive labelling) whose amino acid sequence (12 residues) is the same as the N-terminal sequence of the alpha- and beta-gliadin proteins of the endosperm. Heat stress during grain filling leads to important changes in the synthesis of gluten proteins with reduced synthesis of the high molecular weight (HMW) subunits of glutenin, and continuing synthesis of other gluten proteins, particularly various gliadin proteins. This latter group of polypeptides is thus presumed to be acting as heat-shock proteins, and indeed, multiple heat-shock elements are present in the published sequences of representative genes, up-stream of the coding regions. HPLC analysis (with or without radioactive labelling) shows that there is a resulting change from the normal balance of gluten polypeptides immediately after the shock as well as in the mature grain. As a result, there is a lower proportion of large-sized aggregates of glutenin and weaker dough properties. This scenario indicates that it should be possible to identify genotypes that would be tolerant to stressrelated variations in quality by analysis of gluten composition and, at the gene level, by screening for heat-stress elements in the genes encoding HMW-glutenin subunits. In addition, heat stress modifies the particle size distribution of the starch fraction of mature grain, producing an increase in the proportion of large (A-type) starch granules. No change in chemical structure was detectable as a result of heat stress.

Interspecific- and acclimation-induced variation in levels of heat-shock proteins 70 (hsp70) and 90 (hsp90) and heat-shock transcription factor-1 (HSF1) in congeneric marine snails (genusTegula): implications for regulation ofhspgene expression

2002 ◽  
Vol 205 (5) ◽  
pp. 677-685 ◽  
Author(s):  
Lars Tomanek ◽  
George N. Somero
Keyword(s):  
Transcription Factor ◽  
Heat Stress ◽  
Heat Shock ◽  
Heat Shock Proteins ◽  
Solid Phase ◽  
Heat Shock Gene ◽  
Model Account ◽  
Warm Acclimation ◽  
Induced Variation ◽  
Shock Proteins

SUMMARYIn our previous studies of heat-shock protein (hsp) expression in congeneric marine gastropods of the genus Tegula, we observed interspecific and acclimation-induced variation in the temperatures at which heat-shock gene expression is induced (Ton). To investigate the factors responsible for these inter- and intraspecific differences in Ton, we tested the predictions of the ‘cellular thermometer’ model for the transcriptional regulation of hsp expression. According to this model, hsps not active in chaperoning unfolded proteins bind to a transcription factor, heat-shock factor-1 (HSF1), thereby reducing the levels of free HSF1 that are available to bind to the heat-shock element, a regulatory element upstream of hsp genes. Under stress, hsps bind to denatured proteins, releasing HSF1, which can now activate hsp gene transcription. Thus, elevated levels of heat-shock proteins of the 40, 70 and 90 kDa families (hsp 40, hsp70 and hsp90, respectively) would be predicted to elevate Ton. Conversely, elevated levels of HSF1 would be predicted to decrease Ton. Following laboratory acclimation to 13, 18 and 23°C, we used solid-phase immunochemistry (western analysis) to quantify endogenous levels of two hsp70 isoforms (hsp74 and hsp72), hsp90 and HSF1 in the low- to mid-intertidal species Tegula funebralis and in two subtidal to low-intertidal congeners, T. brunnea and T. montereyi. We found higher endogenous levels of hsp72 (a strongly heat-induced isoform) at 13 and 18°C in T. funebralis in comparison with T. brunnea and T. montereyi. However, T. funebralis also had higher levels of HSF1 than its congeners. The higher levels of HSF1 in T. funebralis cannot, within the framework of the cellular thermometer model, account for the higher Ton observed for this species, although they may explain why T. funebralis is able to induce the heat-shock response more rapidly than T. brunnea. However, the cellular thermometer model does appear to explain the cause of the increases in Ton that occurred during warm acclimation of the two subtidal species, in which warm acclimation was accompanied by increased levels of hsp72, hsp74 and hsp90, whereas levels of HSF1 remained stable. T. funebralis, which experiences greater heat stress than its subtidal congeners, consistently had higher ratios of hsp72 to hsp74 than its congeners, although the sum of levels of the two isoforms was similar for all three species except at the highest acclimation temperature (23°C). The ratio of hsp72 to hsp74 may provide a more accurate estimate of environmental heat stress than the total concentrations of both hsp70 isoforms.

scholarly journals Proteomic analysis of heat shock proteins in maize (Zea mays L.)

2019 ◽  
Vol 43 (1) ◽  
Author(s):  
Mahmoud Hussien Abou-Deif ◽  
Mohamed Abdel-Salam Rashed ◽  
Kamal Mohamed Khalil ◽  
Fatma El-Sayed Mahmoud
Keyword(s):  
Heat Treatment ◽  
Heat Stress ◽  
Heat Shock ◽  
Heat Shock Proteins ◽  
Proteome Analysis ◽  
High Temperature Stress ◽  
Heat Treatments ◽  
Maize Plants ◽  
Adverse Influence ◽  
Shock Proteins

Abstract Background Maize is one of the important cereal food crops in the world. High temperature stress causes adverse influence on plant growth. When plants are exposed to high temperatures, they produce heat shock proteins (HSPs), which may impart a generalized role in tolerance to heat stress. Proteome analysis was performed in plant to assess the changes in protein types and their expression levels under abiotic stress. The purpose of the study is to explore which proteins are involved in the response of the maize plant to heat shock treatment. Results We investigated the responses of abundant proteins of maize leaves, in an Egyptian inbred line of maize “K1”, upon heat stress through two-dimensional electrophoresis (2-DE) on samples of maize leaf proteome. 2-DE technique was used to recognize heat-responsive protein spots using Coomassie Brilliant Blue (CBB) and silver staining. In 2-D analysis of proteins from plants treated at 45 °C for 2 h, the results manifested 59 protein spots (4.3%) which were reproducibly detected as new spots where did not present in the control. In 2D for treated plants for 4 h, 104 protein spots (7.7%) were expressed only under heat stress. Quantification of spot intensities derived from heat treatment showed that twenty protein spots revealed clear differences between the control and the two heat treatments. Nine spots appeared with more intensity after heat treatments than the control, while four spots appeared only after heat treatments. Five spots were clearly induced after heat treatment either at 2 h or 4 h and were chosen for more analysis by LC-MSMS. They were identified as ATPase beta subunit, HSP26, HSP16.9, and unknown HSP/Chaperonin. Conclusion The results revealed that the expressive level of the four heat shock proteins that were detected in this study plays important roles to avoid heat stress in maize plants.

scholarly journals Proteome and Transcriptome Reveal Involvement of Heat Shock Proteins and Indoleacetic Acid Metabolism Process in Lentinula Edodes Thermotolerance

2018 ◽  
Vol 50 (5) ◽  
pp. 1617-1637 ◽  
Author(s):  
Gang-Zheng Wang ◽  
Chao-Jun Ma ◽  
Yi Luo ◽  
Sha-Sha Zhou ◽  
Yan Zhou ◽  
...  
Keyword(s):  
Heat Stress ◽  
Heat Shock ◽  
Heat Shock Proteins ◽  
Indoleacetic Acid ◽  
Lentinula Edodes ◽  
Acid Biosynthesis ◽  
Over Expression ◽  
Indoleacetic Acid Biosynthesis ◽  
Shock Proteins ◽  
Exogenous Iaa

Background/Aims: Heat stress could cause huge losses for Lentinula edodes in China and other Asian cultivation areas. Yet our understanding of mechanism how to defend to heat stress is incomplete. Methods: Using heat-tolerant and heat-sensitive strains of L. edodes, we reported a combined proteome and transcriptome analysis of L. edodes response to 40 °C heat stress for 24 h. Meanwhile, the effect of LeDnaJ on the thermotolerance and IAA (indoleacetic acid) biosynthesis in L. edodes was analyzed via the over-expression method. Results: The proteome results revealed that HSPs (heat shock proteins) such as Hsp40 (DnaJ), Hsp70, Hsp90 and key enzymes involved in tryptophan and IAA metabolism process LeTrpE, LeTrpD, LeTam-1, LeYUCCA were more highly expressed in S606 than in YS3357, demonstrating that HSPs and tryptophan as well as IAA metabolism pathway should play an important role in thermotolerance. Over-expression of LeDnaJ gene in S606 strains showed better tolerance to heat stress. It was also documented that intracellular IAA accumulation of S606 (8-fold up) was more than YS3357 (2-fold up), and exogenous IAA enhanced L. edodes tolerance to heat stress. Conclusion: Our data support the interest of LeTrpE, LeDnaJ, tryptophan and IAA could play a pivotal role in enhancing organism thermotolerance.

Sign in / Sign up

Export Citation Format

Share Document