ACTIVATION OF MULTIPLE TRANSCRIPTION FACTORS AND FOS AND JUN GENE FAMILY EXPRESSION IN CELLS EXPOSED TO A SINGLE ELECTRIC PULSE

We report that exposure of cells to a single electric pulse (250-1250 V/cm) results in the rapid and persistent activation of the DNA bindin g activities of a number of transcription factors, including AP-1, SP1 , AP-2, and NF-kappa B, and the transient expression of select members of the fos and jun gene families. Induction of gene expression occurs primarily at the level of transcription, although c-jun expression al so appears to be regulated posttranscriptionally. Interestingly, maxim al induction of gene expression is detected at electrical field streng ths that do not result in pore formation in the plasma membrane and th at do not significantly affect cell viability. Exposure of cells to el ectric pulses does not result in the activation of HSF1 DNA binding ac tivity, or the induction of hsp70 or p53 protein synthesis, indicating that the induction of fos and jun gene expression is not coincident w ith protein or DNA damage. The results of these studies suggest that e lectrical pulses may represent a novel mechanism for inducing the acti vities of multiple transcription factors and the expression of select members of the fos and jun gene families. (C) Academic Press, Inc.