Heat shock genes encode proteins (hsp's) that play important structural roles under normal circumstances and are essential to the cells' ability to survive environmental insults. Evidence is presented herein that transcriptional regulation of hsp gene expression is linked with the regulation of overall protein synthesis as well as with the accumulation of proteins denatured by stressful events....

The human oesophageal epithelium is subject to damage from thermal stresses and low extracellular pH that can play a role in the cancer progression sequence, thus identifying a physiological model system that can be used to determine how stress responses control carcinogenesis. The classic heat shock protein HSP70 is not induced but rather is down-regulated after thermal injury to squamous epit...

When cells are exposed to heat shock, heavy metals, amino acid ana logues, and other stresses, the heat shock transcription factor (HSF) is activated. The HSF then binds to the promoter of the heat shock genes, stimulating transcription of the heat shock proteins. Here, we demonstrate that exposure of NIH-3T3 cells to oxidanls iI1..O, or menadione) also causes activation of the HSF. This activa...

We isolated and characterized a sequence coding for heat-shock protein 70 (HSP70) of the amphibian Pleurodeles waltl. Results from S1 nuclease protection assays led us to conclude that an hsp70 gene, strictly inducible in somatic cells during heat shock, is constitutively active during oogenesis. By quantitative northern and western blot analysis, we showed that both hsp70 mRNA and HSP70-relate...

Causes of lower induction of Hsp70 in neurons during heat shock are still a matter of debate. To further inquire into the mechanisms regulating Hsp70 expression in neurons, we studied the activity of Heat Shock Factor 1 (HSF1) and histone posttranslational modifications (PTMs) at the hsp70 promoter in rat cortical neurons. Heat shock induced a transient and efficient translocation of HSF1 to ne...

Cells exposed to several forms of stress, such as heat shock, transiently synthesize a group of proteins called heat shock proteins (hsps). Although many stressors other than heat shock are known to induce hsps, inhibitors of hsp expression have never been reported. Here we show that quercetin and several other flavonoids inhibit the synthesis of hsps induced by heat shock in two human cell lin...

Stress (biotic or abiotic) is an unfavourable condition for an organism including fungus. To overcome stress, organism expresses heat-shock proteins (Hsps) or chaperons to perform biological function. Hsps are involved in various routine biological processes such as transcription, translation and posttranslational modifications, protein folding, and aggregation and disaggregation of proteins. T...

The HSP70 heat-shock proteins are molecular chaperones that assist other proteins in their folding, transport and assembly into complexes. Most of these proteins are either constitutively expressed or their expression is induced by heat shock and other stresses. However, two members of the Hsp70 family (HSP70-2 and HSC70T in mice) are regulated developmentally and expressed specifically in sper...

In an effort to devise schemes to site-specifically deliver drugs “on demand” we have leveraged the inducible expression properties of the well-characterized class of stress-response factors, the heat shock proteins. We asked whether a small molecule ligand selective for such proteins could be used as a potential theranostic platform. By conjugating a fluorescent dye to a recently identified nu...

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...