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Presentation Title: Measurement of Alkali-Labile Sites in Plasmid DNA Exposed to Uranyl Acetate Discipline: Department of Chemistry and Biochemistry School: Northern Arizona University Presentation Type: Poster Presentation Abstract: Measurement of Alkali-Labile Sites in Plasmid DNA Exposed to Uranyl Acetate Janice Wilson, Diane M. Stearns, Ph.D. Department of Chemistry and Biochemistry, Northern Arizona University

Uranium is an important emerging toxicant whose use is fast outpacing the rate at which we are learning about its health effects. Previous work in our lab has shown that uranyl acetate (UA) could be activated by either ascorbate (vitamin C) or UVB radiation to form DNA strand breaks in pBR322 plasmid DNA. The purpose of the current project was to develop a protocol to assess the presence of uranium-DNA adducts, and then to quantify their presence in plasmid DNA exposed to the above reaction conditions. A method was successfully developed in which warm piperidine was used to convert U-DNA adducts to akali-labile sites, which would then hydrolyze. The hydrolyzed DNA could be visualized and quantified by gel electrophoresis. We hypothesized that if U-DNA adducts were present, then warm piperidine treatment would degrade more DNA compared to the same reaction conditions in the absence of piperidine. Conversely, if U-DNA adducts were not present, then warm piperidine would have no affect. Data supported our hypothesis. For reactions of UA and ascorbate, piperidine treatment resulted in 46% degradation of DNA, a loss that was not seen in control reactions. For reactions of UA and a range of UVB radiation, piperidine treatment resulted in 15-23% degradation of DNA, which again was not seen in control reactions. This work is significant because it establishes a new method to quantify U-DNA adducts, which if present in humans exposed to uranium could be another source of mutations that may lead to cancer.

Presenter: Janice Wilson Tribe: Navajo Primary Email: Biography Hi, my name is Janice Wilson, I am a member of the Navajo tribe, from Many Farms, AZ. I am a graduate of DinÊ College and received my Associates of Science with options in Health Occupations in 2010. I transferred to Northern Arizona University this semester and have applied to the Nursing program to pursue my Bachelors of Science in Nursing. I am an Otten’s fellowship recipient and am working with my mentor on Undergraduate research in the area of the effects of uranium on DNA.


2011 National Conference Student Research Abstracts  
2011 National Conference Student Research Abstracts  

A comprehensive list of the student research topics that will be presented at the AISES 2011 National Conference