INHIBITORS OF PROTEASES AND OTHER STRESSORS INDUCE LOW-MOLECULAR-WEIGHT HEAT-SHOCK PROTEINS IN SACCHAROMYCES-CEREVISIAE

Gröpper, T., and Rensing, L. 1993. Inhibitors of proteases and other stressors induce low-molecular-weight heat-shock proteins in Saccharomyces cerevisiae. Experimental Mycology 17, 46-54. During the first 30 min of heat shock (40°C) in Saccharomyces cerevisiae novel, small heat-shock proteins (HSP) (24, 20, 19, 14, and 12 kDa) were slightly induced. They accumulated during the following 1-3 h. Several agents (H2O2, alcohols, and formaldehyde) enhanced the synthesis rate of these proteins to a greater extent than heat shock. Five synthetic protease inhibitors demonstrated the greatest inducing effects on the small HSPs, but did not affect the large HSPs. Thus, the small heat-shock proteins cannot be degradation products of the large ones. Experiments with heat shock applied together with high concentrations of alcohols or dimethyl sulfoxide revealed an inhibition of heat-shock proteins. © 1993 Academic Press. All rights reserved.