Environmental magnetic fields change complementary DNA synthesis in cell-free systems.

Abstract

A number of studies have shown that exposures to environmental magnetic fields (MFs) increase cellular transcription and enhance DNA synthesis. However, little is known about the basic mechanisms underlying specific biological responses to MFs. We looked directly at the effect of MFs by using a cell-free rabbit globin cDNA synthesis system. cDNA synthesis reaction mixtures were placed in each of four exposure conditions and were tested simultaneously. Condition one was the control, with no exposure during either single-strand or double-strand synthesis (M-M-). The second condition was MF exposure only during single-strand synthesis (M+M-). The third condition was exposure only during double-strand synthesis (M-M+). The fourth condition was exposure during both single-strand and double-strand synthesis (M+M+). Results showed that cDNA synthesis was affected by 5-100 microT, 60 Hz MFs. Double-strand cDNA synthesis increased with MF exposure only during double-strand synthesis reactions (M-M+), and the greatest increase of double-strand cDNA synthesis was detected when MF exposure was at 10 microT, only during double-strand synthesis. Double-strand cDNA synthesis decreased when only single-strand synthesis reactions were exposed (M+M-; 100 microT). An increase of cDNA synthesis caused increased synthesis of rabbit globin cDNA and large-sized molecules. These results suggest that exposure to MF induced structural changes of synthesized cDNA, therefore altering the amount of cDNA. Our results show that environmental MFs can significantly alter cDNA synthesis in a cell-free system.