Editors’ Note Added in Proof: Stress Proteins: Heat-Shock Proteins/Molecular Chaperones

Abstract

Investigations in the last few years led to the discovery of stress proteins and their catalytic roles in the folding of nascent proteins, as well as in the maintenance of/refolding native functional protein conformations in the face of stress-related insult. Insult to the cell environment activates a set of genes which express proteins that can repair stress-induced molecular damage to proteins and reestablish normal homeostasis. The standardizeh form of stress that has been used in studies with prokaryotic and eukaryotic cell cultures is exposure to unusually elevated temperatures (e.g., 42°C). This evokes a heat-shock response by inducing the dramatically enhanced expression of heat-shock-proteins (Hsp) to stabilize and reestablish partially denatured protein conformations. Under normal conditions Hsp’s are expressed at relatively low levels.