RESUMO
<p><b>OBJECTIVE</b>To clone and identify MF-1 gene which responded to extremely low frequency magnetic fields(ELF MF) in Daudi cells, and explore the response universality of MF-1 gene in several MF-sensitive cell lines, so as to provide experimental basis for revealing the mechanism of biological effects induced by magnetic field.</p><p><b>METHODS</b>The DNA fragment of MF-1 was cloned and sequenced; the mRNA level of MF-1 gene were analysed in MF-sensitive cell lines(HL-60, L1210 and CHL) by Northern blot after these cells being treated with 0.1 mT and 0.8 mT MF for 20 minutes and 24 hours, respectively.</p><p><b>RESULTS</b>The MF-1 cDNA sequence had 100% homology with cytochrome oxidase subunit 1 gene(CO1) by searching Gene Bank database; the transcription of CO1 in HL-60, L1210 and CHL cell lines which exposed to 0.1 mT and 0.8 mT MF for 20 minutes were significantly lower(0.38 +/- 0.12 and 0.37 +/- 0.04) than that of control(0.58 +/- 0.12) and so did for 24 hours exposure(0.46 +/- 0.09 and 0.45 +/- 0.09 vs 0.65 +/- 0.06) (P < 0.05).</p><p><b>CONCLUSION</b>CO1 is a MF-responsive gene. Cytochrome oxidase activity may be affected through low level of CO1 transcription by magnetic fields, thus induce bioeffects in organisms.</p>
