HEAT-INDUCED STRESS PROTEINS AND THE CONCEPT OF MOLECULAR CHAPERONES

Heat stress proteins can be assigned to eleven protein families conser ved among bacteria, plants and animals. Most of them aid other protein s to maintain or regain their native conformation by stabilizing parti ally unfolded states. Hence, they are called molecular chaperones. Exp erimental data indicate that many of them form heterooligomeric comple xes, so-called chaperone machines, interacting with each other to gene rate a network for maturation, assembly and intracellular targeting of proteins. In this review we summarize the essential information on th e structure and function of chaperone and chaperone complexes. In addi tion we present a compilation of in vitro and in vivo test systems use d in the preceding ten years of chaperone research.