Induction of heat shock proteins in Chinese hamster ovary cells and development of thermotolerance by intermediate concentrations of puromycin

摘要: During 4 hr after puromycin (PUR: 20 micrograms/ml) treatment, the synthesis of three major heat shock protein families (HSPs: Mr = 110,000, 87,000, and 70,000) was enhanced 1.5-fold relative to that untreated cells, as studied by one-dimensional gel electrophoresis. The increase unique HSPs, if with two-dimensional gels, would probably be much greater. In parallel, thermotolerance observed at 10(-3) isosurvival a ratio (TTR) either 2 or greater than 5 heating 45.5 degrees C 43 C, respectively. However, induced only intermediate concentrations (3-30 inhibited 15-80%; high concentration PUR (100 95% did not induce HSPs thermotolerance. Also, never any (0.01-10 cycloheximide 5-94%. Furthermore, (20 addition (CHM: 10 micrograms/ml), reduces 94%, both HSP families. Thus, correlated an in newly synthesized This phenomenon compared another termed resistance when cells were heated presence CHM immediately 2-hr pretreatment PUR. Heat protection increased inhibition total Moreover, this decayed rapidly interval between 1-2 hr, have obvious relationship Therefore, there are two distinctly different pathways for developing thermal resistance. first is it requires incubation treatment apparently second before during does require pathway requiring also caused incubated 2-4 following