CHEMICAL INDUCTION OF STRESS PROTEINS DOES NOT INDUCE SPLICING THERMOTOLERANCE UNDER CONDITIONS PRODUCING SURVIVAL THERMOTOLERANCE

Cell survival during a severe heat stress can be enhanced when heat sh ock proteins are induced prior to the severe heat treatment. Induction can be accomplished either by heat or chemical treatments. The increa se in survival at these severe elevated temperatures after pretreatmen t has been referred to as thermotolerance, which we now refer to as su rvival thermotolerance. It has also been shown previously that mild he at treatment allows splicing in cells subjected to a severe heat treat ment, now referred to as splicing thermotolerance. The experiments sho wn here demonstrate that even though chemical induction of the heat sh ock proteins leads to survival thermotolerance, this same treatment do es not induce splicing thermotolerance. These are the first results th at demonstrate at least two distinct aspects of thermotolerance. (C) 1 994 Academic Press, Inc.