Are Your Water Systems Safe? A Study on CYP1A Expression in Brown Bullhead and Channel Catfish in Response to Sediment Exposure From Killbuck Creek Wooster, Ohio

Name: Madison Elizabeth Carter
Major: Biology
Advisor: Rebecca Williams

CYP1A gene expression responds to pollutants in the environment, specifically PAHs. CYP1A is a significant biomarker that is useful for assessing clean and polluted environments. Fish in contaminated sites are expected to have higher expression of CYP1A, indicating there are more pollutants. Fish in clean sites are expected to have lower CYP1A expression, suggesting there are minimal pollutants in the environment. My research cohort investigated four different topics: sediment analysis, single PAH influence on CYP1A induction, Group of PAHs influence on CYP1A induction, and genome differences in clean versus contaminated fish. This study evaluated CYP1A protein expression in Brown bullhead (Ameiurus nebulosus) and Channel Catfish (Ictalurus punctatus) in response to sediment collected from two sites in Killbuck Creek Wooster, Ohio; one clean (reference) and experimental (contaminated). Western immunoblotting quantified the CYP1A protein in each sample from the clean and polluted sites. CYP1A expression was highest in the clean site in both bullhead and catfish, while the CYP1A expression was lowest in the experimental (contaminated sediment) group of both bullhead and catfish. These results suggest a relationship between CYP1A induction and multiple PAHs in the environment. However, the cumulative effect of PAHs versus the effect of a single PAH on CYP1A expression are not well known and needs more clarity. Additionally, higher concentrations of CYP1A in the clean site may indicate a potential adaptation at play in the CYP1A biomarker gene. Further research needs to investigate CYP1A gene variants overtime in bullhead and catfish to make more solidified support of selection for the CYP1A variant.

It was very exciting to see the results I got in my study to be able to interpret the quality of the Water systems here in Wooster, Ohio. Especially, since my results were opposite of normal trends found in similar studies, which can suggest potential adaptation. A future I.S. student is using my samples next year to run the methodology again and it would be interesting to see if the results are similar or different. They are also doing an assessment of other locations (Cuyahoga, Lake Erie, and East Palestine) as well. It would be very exciting to see those results compared to Wooster, Ohio and to see if there is more support for adaptation at play in the CYP1A variant gene.

Posted in Comments Enabled, Independent Study, Symposium 2023 on April 20, 2023.

One response to “Are Your Water Systems Safe? A Study on CYP1A Expression in Brown Bullhead and Channel Catfish in Response to Sediment Exposure From Killbuck Creek Wooster, Ohio”

1. Dr. Williams says:

   April 21, 2023 at 10:59 am

   Congratulations Madison! Best wishes for the day.