K. Kaarniranta et al., Protein synthesis is required for stabilization of hsp70 mRNA upon exposure to both hydrostatic pressurization and elevated temperature, FEBS LETTER, 475(3), 2000, pp. 283-286
We have recently described that in chondrocytic cells high hydrostatic pres
sure (HP) causes a heat shock response via mRNA stabilization without a tra
nscriptional activation of the hsp70 gene. In this study, we investigated w
hether this exceptional regulatory mechanism occurs more generally in diffe
rent types of cells. Indeed, hsp70 mRNA and protein accumulated in HeLa, Ha
Cat and MG-63 cells under 30 MPa HP, without DNA-binding of heat shock tran
scription factor 1 (HSF1) to the heat shock element of the hsp70 gene or fo
rmation of nuclear HSF1 granules, revealing a lack of transcriptional activ
ation. Moreover, we observed that protein synthesis is needed for mRNA stab
ilization. Thus, high HP offers a model to study the mechanisms of hsp70 mR
NA stabilization without HSF1-mediated induction of the heat shock gene res
ponse. (C) 2000 Federation of European Biochemical Societies. Published by
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