Natural Science Forum / Biology / Biology / January 2008

full text @ http://www.biomagres.com/content/4/1/7

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Anna-Lisa Paul1 , Robert J Ferl1  and Mark W Meisel2

1Department of Horticultural Sciences and The Biotechnology Program,
University of Florida, Gainesville, FL 32611-0690, USA
2Department of Physics and National High Magnetic Field Laboratory,
University of Florida, Gainesville, FL 32611-8440, USA

Abstract
Background
High magnetic fields are becoming increasingly prevalent components of
non-invasive, biomedical imaging tools (such as MRI), thus, an
understanding of the molecular impacts associated with these field
strengths in biological systems is of central importance. The
biological impact of magnetic field strengths up to 30 Tesla were
investigated in this study through the use of transgenic Arabidopsis
plants engineered with a stress response gene consisting of the
alcohol dehydrogenase (Adh) gene promoter driving the β-glucuronidase
(GUS) gene reporter.

Methods
Magnetic field induced Adh/GUS activity was evaluated with
histochemical staining to assess tissue specific expression and
distribution, and with quantitative, spectrofluometric assays to
measure degree of activation. The evaluation of global changes in the
Arabidopsis genome in response to exposure to high magnetic fields was
facilitated with Affymetrix Gene Chip microarrays. Quantitative
analyses of gene expression were performed with quantitative real-time
polymerase-chain-reaction (qRT-PCR).

Results
Field strengths in excess of about 15 Tesla induce expression of the
Adh/GUS transgene in the roots and leaves. From the microarray
analyses that surveyed 8000 genes, 114 genes were differentially
expressed to a degree greater than 2.5 fold over the control. These
results were quantitatively corroborated by qRT-PCR examination of 4
of the 114 genes.

Conclusion
The data suggest that magnetic fields in excess of 15 Tesla have far-
reaching effect on the genome. The wide-spread induction of stress-
related genes and transcription factors, and a depression of genes
associated with cell wall metabolism, are prominent examples. The
roles of magnetic field orientation of macromolecules and
magnetophoretic effects are discussed as possible factors that
contribute to the mounting of this response.