Molecular chaperones: heat-shock proteins, foldases, and matchmakers.

The term molecular chaperone includes a large family of unrelated proteins that comprise both stress-inducible and constitutive molecules. In recent years, molecular chaperones or heat-shock proteins (Hsps) have emerged as fundamentally important topics in cell biology. Living organisms respond to stressful conditions, such as heat shock, by rapidly producing a relatively small class of specific proteins that function to stabilize cellular components against stress. Hsps or molecular chaperones function by preventing misfolding of newly synthesized proteins, escorting proteins targeted for other cellular compartments, and modulating or regulating proteins involved in cell growth and differentiation. Clearly these proteins are of enormous importance to cellular function but of even more importance in helping to fight disease. From heart tissue protection after coronary thrombosis to the regulation of tumor suppressor activity to the use of these molecules as new diagnostic and therapeutic agents, molecular chaperones offer scientists many potential rewards. This review provides an insider's peek at molecular chaperones--a most indispensable set of molecules for cell growth, survival, and regulation.