Scientific research is designed to build knowledge and explore. Sometimes, that means changing previous ideas. In the US, we have a system that reviews and updates toxic chemicals. In 2017, benzo[a]pyrene (BaP) was updated. BaP is a polycyclic aromatic hydrocarbon (PAH) (https://superfund.oregonstate.edu/all-about-pahs). It is also a carcinogen. Exposure to a carcinogen may increase cancer risk.

The review of BaP found it to be 7 times less toxic than previously thought. However, it is still a carcinogen. This change may impact Superfund sites that have PAHs as pollutants. Why? Because BaP is used as a standard of toxicity for 6 other carcinogenic PAHs. When the toxicity of BaP changes, it changes these other PAHs. This means that BaP and 6 other PAHs will be considered 7 times less carcinogenic. We developed a one-page infographic describing this change (https://superfund.oregonstate.edu/sites/superfund.oregonstate.edu/files/image-album/infographics/infographics_0.jpg). The Portland Harbor Superfund site has BaP and other PAHs. Only BaP and 6 PAHs will be affected by the change in toxicity. Other PAHs will not be changed.

Want to learn more about PAHs? Check out our newest research:  https://www.researchgate.net/project/Superfund-Research-Program-at-Oregon-State-University

 

By Mike Garland and Mitra Geier

 

This past fall, we traveled to the Pacific Northwest National Laboratory (PNNL) for training in computational analysis of RNA-seq data. During this two-day externship, we worked with PNNL scientists as they walked us through our data and gave us an overview of computational approaches they use to analyze RNA-seq data.

 

Research Impacts

During the externship we were provided hands-on experience with computational methods under the guidance of experts. Our ultimate goal was to apply what we learned at PNNL to current and future RNA-seq projects.

Our work at PNNL centered around an experiment that compared regenerating vs non-regenerating caudal fins of zebrafish, which is a phenomenon of interest for a variety of applications.  The regenerating caudal fin model is a useful toxicological tool for chemical screening, and is well-suited for studying how chemical exposure can lead to changes in molecular signaling events that occur during the wound healing process. Furthermore, regeneration and development share many critical signaling events, making this model useful for interrogating mechanisms of developmental toxicity.

By using a systems approach to understand expression patterns of mRNA and miRNA during regeneration, we can improve our understanding of molecular processes involved in wound healing. This would allow us to be better-informed when making hypotheses about the mechanisms of toxicity following chemical exposure in zebrafish. Given the applicability of this model to developmental toxicology, the results from this experiment will be particularly useful for future directions of SRP Project 3.

Age is a known factor of regenerative ability, and different life stages are frequently used in various toxicological studies.  This was incorporated into the experiment using age-based cohorts and we learned methods to compare age-dependent differences in gene expression during regeneration. Drs. Joe Brown and Jason Wendler, both computational biologists at PNNL, trained us over our externship on a variety of methodologies including quality control, read alignment, statistical inference, biological pathway enrichments, and data visualization methods.

 

Career Impacts

Over the course of the two days, we covered many computational methods involved in RNA-seq data analysis, which will be useful in our other ongoing projects, as well as future work as our careers progress. We are also grateful for the opportunities for professional networking outside of our typical academic circles. We learned quite a bit about the mechanics of working in a national laboratory and how that is different than working for a university. We are appreciative of the time and effort put in by Drs. Brown and Wendler, and we also thank Dr. Katrina Waters who helped organize our trip to PNNL.

Working with the RTC, SRP trainee Sydelle Harrison coordinated a campus visit for students from the Confederated Tribes of the Warm Springs Reservation and the Confederated Tribes of the Umatilla Indian Reservation (CTUIR) on May 13-14. Students went on a campus tour, ate lunch at the Eena Haws Native American Longhouse Annual Salmon Bake, and met with Dr. Rohlman (CEC, RTC) to learn about recent tribal-university collaborations (more information available here). The tour culminated in a hands-on lab activity wherein students learned how to isolate DNA from strawberries as a proxy for understanding how SRP investigators can learn underlying genetic determinants of disease by analyzing DNA. This event was a collaborative effort between the Research Translation Core, Training Core, Administrative Core and Community Engagement Core.