Skip Navigation



ToxSci Advance Access published online on February 16, 2008
Toxicological Sciences, doi:10.1093/toxsci/kfn034
This Article
Right arrow Advance Access manuscript (PDF) Freely available
Right arrow All Versions of this Article:
103/1/68    most recent
kfn034v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Zhang, M.
Right arrow Articles by Xiao, W.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Zhang, M.
Right arrow Articles by Xiao, W.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2008. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org

Deletion of Yeast CWP Genes Enhances Cell Permeability to Genotoxic Agents

Min Zhang1, Yuping Liang2, Xiaohua Zhang1, Ying Xu1, Heping Dai1,* and Wei Xiao1,2,*

1 Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072 China 2 Department of Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK S7N 5E5 Canada

* To whom correspondence should be addressed at Institute of Hydrobiology, Chinese Academy of Sciences, 7 Donghu Road South, Wuhan, Hubei, 430072 China. Fax: 86-27-68780123. E-mail: hpdai{at}ihb.ac.cn (H.D.) or Department of Microbiology and Immunology, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK S7N 5E5 Canada. Fax: 306-9666-4311. E-mail: wei.xiao{at}usask.ca (W.X.)

Received December 26, 2007; revision received December 26, 2007; accepted February 7, 2008


  Abstract

We have previously reported the development of a novel genotoxic testing system based on the transcriptional response of the yeast RNR3-lacZ reporter gene to DNA damage. This system appears to be more sensitive than other similar tests in microorganisms, and is comparable to the Ames test. In an effort to further enhance detection sensitivity, we examined the effects of altering major cell wall components on cell permeability and subsequent RNR3-lacZ sensitivity to genotoxic agents. While inactivation of single CWP genes encoding cell wall mannoproteins had little effect, the simultaneous inactivation of both CWP1 and CWP2 had profound effects on the cell wall structure and permeability. Consequently, the RNR3-lacZ detection sensitivity is markedly enhanced, especially to high molecular weight compounds such as 4-nitroquinoline-N-oxide (>7 fold) and phleomycin (>13 fold). In contrast, deletion of genes encoding representative membrane components or membrane transporters had minor effects on cell permeability. We conclude that the yeast cell wall mannoproteins constitute the major barrier to environmental genotoxic agents and that their removal will significantly enhance the sensitivity of RNR-lacZ as well as other yeast-based genotoxic tests.

Key Words: RNR3-lacZ; yeast; cell wall; mannoprotein; genotoxicity test; sensitivity; permeability.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.