Regulation and conservation of the heat-shock transcription factor sigma32.

Heat shock and other stresses induce a set of genes encoding molecular chaperones and proteases through increase in the level of transcription factor sigma32 in Escherichia coli. Some of the cis- and trans-acting factors involved in the control of synthesis (translation), degradation and activity of sigma32 have been identified and characterized. These studies contribute to our understanding of early events of the heat-shock response, including modes of interaction between chaperones and sigma32. Besides, analysis of sigma32 homologues from diverse bacteria reveals new insights into evolution of the regulatory mechanisms.