QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

Vol. 15, Issue 9, 4321-4336, September 2004

This Article Full Text Full Text (PDF) All Versions of this Article: E04-05-0375v1 15/9/4321    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Keller-Seitz, M. U. Articles by Fasullo, M. Search for Related Content PubMed PubMed Citation Articles by Keller-Seitz, M. U. Articles by Fasullo, M.

Transcriptional Response of Yeast to Aflatoxin B₁: Recombinational Repair Involving RAD51 and RAD1

Monika U. Keller-Seitz ^*, Ulrich Certa , Christian Sengstag ^*, Friedrich E. Würgler ^*, Mingzeng Sun , and Michael Fasullo  

^* Institute of Toxicology, Swiss Federal Institute of Technology ETH, CH-8603 Schwerzenbach, Switzerland; Pharma Division, F. Hoffmann-La Roche Ltd., CH-4070 Basel, Switzerland; and Ordway Research Institute, Albany, NY 12208-03479

Submitted May 7, 2004; Revised June 9, 2004; Accepted June 14, 2004
Monitoring Editor: Keith Yamamoto

The potent carcinogen aflatoxin B₁ is a weak mutagen but a strong recombinagen in Saccharomyces cerevisiae. Aflatoxin B₁ exposure greatly increases frequencies of both heteroallelic recombination and chromosomal translocations. We analyzed the gene expression pattern of diploid cells exposed to aflatoxin B₁ using high-density oligonucleotide arrays comprising specific probes for all 6218 open reading frames. Among 183 responsive genes, 46 are involved in either DNA repair or in control of cell growth and division. Inducible growth control genes include those in the TOR signaling pathway and SPO12, whereas PKC1 is downregulated. Eleven of the 15 inducible DNA repair genes, including RAD51, participate in recombination. Survival and translocation frequencies are reduced in the rad51 diploid after aflatoxin B₁ exposure. In mec1 checkpoint mutants, aflatoxin B₁ exposure does not induce RAD51 expression or increase translocation frequencies; however, when RAD51 is constitutively overexpressed in the mec1 mutant, aflatoxin B₁ exposure increased translocation frequencies. Thus the transcriptional profile after aflatoxin B₁ exposure may elucidate the genotoxic properties of aflatoxin B₁.

Corresponding author. E-mail address: mfasullo{at}ordwayresearch.org.

This article has been cited by other articles:

				Y. Guo, L. L. Breeden, H. Zarbl, B. D. Preston, and D. L. Eaton Expression of a Human Cytochrome P450 in Yeast Permits Analysis of Pathways for Response to and Repair of Aflatoxin-Induced DNA Damage Mol. Cell. Biol., July 15, 2005; 25(14): 5823 - 5833. [Abstract] [Full Text] [PDF]