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Iwahashi H, Kitagawa E, Suzuki Y, Ueda Y, Ishizawa YH, Nobumasa H, Kuboki Y,
Hosoda H, Iwahashi Y.
Evaluation of toxicity of the mycotoxin citrinin
using yeast ORF DNA microarray and Oligo DNA
microarray.
BMC Genomics. 2007 Apr 5;8:95
Human Stress Signal Research Center,
National Institute of Industrial Science and Technology, AIST,
Tsukuba West, Onogawa Tsukuba, Ibaraki, Japan.
hitoshi.iwahashi@aist.go.jp
BACKGROUND: Mycotoxins are fungal secondary
metabolites commonly present in feed and food, and are widely
regarded as hazardous contaminants. Citrinin, one of the very
well known mycotoxins that was first isolated from Penicillium
citrinum, is produced by more than 10 kinds of fungi, and is
possibly spread all over the world. However, the information on
the action mechanism of the toxin is limited. Thus, we
investigated the citrinin-induced genomic response for
evaluating its toxicity. RESULTS: Citrinin inhibited growth of
yeast cells at a concentration higher than 100 ppm. We monitored
the citrinin-induced mRNA expression profiles in yeast using the
ORF DNA microarray and Oligo DNA microarray, and the expression
profiles were compared with those of the other stress-inducing
agents. Results obtained from both microarray experiments
clustered together, but were different from those of the
mycotoxin patulin. The oxidative stress response genes--AADs,
FLR1, OYE3, GRE2, and MET17--were significantly induced. In the
functional category, expression of genes involved in
"metabolism", "cell rescue, defense and virulence", and "energy"
were significantly activated. In the category of "metabolism",
genes involved in the glutathione synthesis pathway were
activated, and in the category of "cell rescue, defense and
virulence", the ABC transporter genes were induced. To alleviate
the induced stress, these cells might pump out the citrinin
after modification with glutathione. While, the citrinin
treatment did not induce the genes involved in the DNA repair.
CONCLUSION: Results from both microarray studies suggest that
citrinin treatment induced oxidative stress in yeast cells. The
genotoxicity was less severe than the patulin, suggesting that
citrinin is less toxic than patulin. The reproducibility of the
expression profiles was much better with the Oligo DNA
microarray. However, the Oligo DNA microarray did not completely
overcome cross hybridization.
PMID: 17408496 |
