MAGNETIC-FIELD EXPOSURE ENHANCES MESSENGER-RNA EXPRESSION OF SIGMA(32) IN ESCHERICHIA-COLI

The mechanism of interaction between weak electromagnetic fields and c ells is not understood. As a result, the health effect(s) induced by e xposure to these fields remains unclear. In addition to questions rela ting to the site of initial magnetic field (MF) interactions, the natu re of the cell's response to these perturbations is also unclear. We e xamined the hypothesis that the cells respond to MFs in a manner simil ar to other environmental stressors such as heat. Using the bacterium Escherichia coli, we examined the mRNA levels of sigma(32), a protein that interacts with RNA polymerase to help it recognize a variety of s tress promoters in the cell. Our data show that the intracellular leve l of sigma(32) mRNA is enhanced following a 15-min exposure to a 60 Hz , 1.1 mT magnetic field. (C) 1998 Wiley-Liss, Inc.