TRANSCRIPTIONAL REPRESSION OF THE PROINTERLEUKIN 1-BETA GENE BY HEAT-SHOCK FACTOR-1

Heat shock factor 1 activates the promoters of heat shock genes at ele vated temperatures through its interaction with heat shock elements. W e have examined a new role for heat shock factor 1 in the repression o f the prointerluekin 1 beta gene in human monocytes responding to stim ulation with lipopolysaccharide. Both exposure to elevated temperature s and heat-independent heat shock factor 1 expression repressed the tr anscription of the prointerleukin 1 beta gene, and repression was stri ctly dependent on an intact consensus heat shock element in the proint erleukin 1 beta promoter to which heat shock factor 1 bound. This is t he first demonstration of heat shock factor 1 as a transcriptional rep ressor and suggests a role for the factor in the counter-regulation of cytokine gene transcription.