Cytochrome P450 and Glutathione-S-Transferase Activity are Altered Following Environmentally Relevant Atrazine Exposures in Crayfish (Faxoniusvirilis)
The herbicide atrazine is heavily applied in the U.S. Midwest to control broadleaf weeds. It enters local streams and rivers through runoff and seepage, and exposure can affect non-target aquatic organisms, like crayfish. We examined sublethal effects of atrazine on the expression and activity of the detoxification enzymes cytochrome P450 (CYP450) and glutathione-S-transferase (GST) in crayfish. Crayfish were exposed to 0, 10, 40, 80, 100 and 300 ppb atrazine for 1, 2, 4, 7 and 10 days. Their hepatopancreas was collected and CYP450 expression and GST activity was analyzed. Atrazine exposure caused differential expression and activity of CYP450 and GST. CYP450 expression varied over exposure concentrations and time. Further, GST activity significantly increased following a 2 day, 10 ppb exposure to atrazine and a 300 ppb atrazine exposure for all days tested. We found that atrazine detoxification is a dynamic process that changes with the length and intensity of atrazine exposure.
KeywordsAtrazine Hepatopancreas Crayfish Cytochrome P450 Glutathione-S-transferase
This work was supported by the National Institutes of Health (NIH) Common Fund and Office of Scientific Workforce Diversity (Grant Nos. RL5GM118981, TL4GM118983, and 1UL1GM118982) and the University of Detroit Mercy (Faculty Research Award to R.M.B). This work also utilized Core Services at the University of Michigan, which are supported by an NIH grant (Grant No. DK097153).
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