ABSTRACT
Organisms are exposed to a variety of stressful condition that damage important cellular structures and interfere with essential functions. In response to heat and other insults, cells activate an ancient signalling pathway leading to the transient expression of heat shock or heat stress proteins (HSPs). HSPs exhibit sophisticated protection mechanisms that protect the damaged cells. HSPs assist in protein folding, translocation and assembly of newly synthesized polypeptides. They also stabilize proteins during heat shock and other stresses, thus contributing to cell survival after injury. The elevated expression of stress proteins is considered to be a universal response to adverse conditions. In this Review we summarize the concepts of the HSPs protective mechanism.