Abstract
The heat shock response is a universally conserved mechanism protecting cells from external stress. Here we present an overall picture of the heat shock response of E. coli. Under steady state conditions, the DnaK chaperone system downregulates the activity, synthesis and stability of the heat shock transcription factor σ32, which plays a central role in the synthesis of heat shock proteins. Upon heat shock, the downregulation by the DnaK system is overcome and σ32 is induced, leading to rapid and transient induction of heat shock proteins. Degradation of σ32 is mainly achieved by the membrane-bound ATP-dependent protease FtsH.
