The heat shock response in yeast is regulated by the interaction between a chaperone protein and a heat shock transcription factor, and fine-tuned by phosphorylation.

Heat shock at 42°caused a rapid inhibition of protein synthesis in Reuber H35 hepatoma cells. Inhibition was maximal within 5 min after the temperature was increased. After heat shock at 42°for 30 min, protein synthesis was restored in 4 to 5 hr. Heat shock did not inhibit amino acid transport or cause a decrease of cellular amino acid pools, excluding a direct effect of these parameters on t...

Heat shock leads to accumulation of polyadenylated RNA in nuclei of Saccharomyces cerevisiae cells, transcriptional induction of heat shock genes, and efficient export of polyadenylated heat shock mRNAs. These studies were conducted to examine the requirements for export of mRNA following heat shock. We used in situ hybridization to detect SSA4 mRNA (encoding Hsp70) and flow cytometry to measur...

To characterize heat-shock proteins (HSPs) of the 70-kDa family in the crayfish medial giant axon (MGA), we analyzed axoplasmic proteins separately from proteins of the glial sheath. Several different molecular weight isoforms of constitutive HSP 70s that were detected on immunoblots were approximately 1-3% of the total protein in the axoplasm of MGAs. To investigate inducible HSPs, MGAs were h...

Heat shock factor 1 (HSF1) is the ubiquitous stress-responsive transcriptional activator which is essential for the inducible transcription of genes encoding heat shock proteins and molecular chaperones. HSF1 localizes within the nucleus of cells exposed to heat shock, heavy metals, and amino acid analogues, to form large, irregularly shaped, brightly staining granules which are not detected du...

Heme oxygenase-l is an essential enzyme in heme catabolism, and its human gene promoter contains a putative heat shock element (HHO-HSE). This study was designed to analyze the regulation of human heme oxygenase-l gene expression under thermal stress. The amounts of heme oxygenase-l protein were not increased by heat shock (incubation at 42°C) in human alveolar macrophages and in a human eryth...

Heat shock factor (HSF) binds to heat shock elements (HSEs) and the binding can be highly cooperative. Here we report an analysis of binding of Drosophila HSF to both native and synthetic heat shock regulatory regions. We find that cooperative binding of HSF requires close proximity, rather than helical alignment, of HSEs. Two or more trimeric HSEs organized as contiguous 5 bp units show much h...

High levels of regulated oncogen-alpha (GRO-a) expression have been observed in the liver. GRO-a stimulates proliferation of epithelial cells and induction of rolling and extravascular migration of neutrophils and mononuclear cells. Given the above observations, this chemokine was chosen to be analyzed in freshly isolated and cultured hepatocytes. In this study, hepatocytes (2×106 cell/ml) were...

Bacterial and viral triggers are suspected agents in the initial etiology of autoimmune diseases. There are some studies on the etiology of autoimmune disorders which have focused on streptococcal infection and a possible relation with microbial heat shock proteins (hsp) which show significant homology with human heat shock proteins. In addition, some serotypes of streptococci cross-react ...

Using beta-galactosidase and luciferase as reporter enzymes, we have previously shown that enzymatic inactivation occurring during a heat shock is concomitant with protein insolubilization (Nguyen, V. T., Morange, M., and Bensaude, O. (1989) J. Biol. Chem. 264, 10487-10492). In this paper, we observe that pretreatment of cells with D2O and glycerol, compounds known to stabilize protein structur...