Carcinogenesis, Vol 19, 1673-1678, Copyright © 1998 by Oxford University Press
C Kaplanski, CP Wild and C Sengstag
The role of aflatoxin B1 (AFB1) in the induction of rearrangements
affecting minisatellite sequences was studied in an in vitro yeast model.
The Saccharomyces cerevisiae strain used expresses human cytochrome P450
1A2 and NADPH-cytochrome P450 oxidoreductase and has previously been used
to study genetic recombination events induced by AFB1. DNA multilocus
fingerprinting was performed using probe M13 core hybridizing to a set of
hypervariable minisatellite sequences in S. cerevisiae. Frequent
spontaneous genomic alterations that affect the minisatellite fingerprint
pattern were observed. Control cultures showed 15.8% rearrangements in
minisatellites, and this frequency increased to 40.0% in cultures exposed
to AFB1 (80 microg/ml). A total of approximately 29 minisatellite loci were
visualized for each culture. Given the number of cultures examined (40
AFB1-treated and 38 controls) the rearrangement frequency per detectable
minisatellite was 2.59% in the AFB1-treated group and 0.73% in the control
group, which represents a statistically significant (P = 0.001) difference.
Thus, our data strongly suggest that AFB1 can promote the genetic events
responsible for minisatellite rearrangements in the yeast genome. Such
genetic rearrangements may be important events during the etiology of liver
carcinogenesis in people chronically exposed to dietary aflatoxins.
ARTICLES
Rearrangements in minisatellite sequences induced by aflatoxin B1 in a metabolically competent strain of Saccharomyces cerevisiae
Unit of Environmental Carcinogenesis, International Agency for Research on Cancer, Lyon, France.
![]()
CiteULike
Connotea
Del.icio.us What's this?