Grantee Research Project Results
2016 Progress Report: Development of a larval fish neurobehavior adverse outcome pathway to predict effects of contaminants at the ecosystem level and across multiple ecologically relevant taxa
EPA Grant Number: R835798Title: Development of a larval fish neurobehavior adverse outcome pathway to predict effects of contaminants at the ecosystem level and across multiple ecologically relevant taxa
Investigators: Murphy, Cheryl A. , Carvan, Michael , Jones, Michael , Garcia-Reyero, Natàlia
Current Investigators: Murphy, Cheryl A. , Garcia-Reyero, Natàlia , Carvan, Michael , Jones, Michael
Institution: Michigan State University , Mississippi State University , University of Wisconsin - Milwaukee
Current Institution: Michigan State University , University of Wisconsin - Milwaukee , Mississippi State University
EPA Project Officer: Spatz, Kyle
Project Period: June 1, 2015 through May 31, 2018 (Extended to May 31, 2021)
Project Period Covered by this Report: May 1, 2016 through April 30,2017
Project Amount: $800,000
RFA: Systems-Based Research for Evaluating Ecological Impacts of Manufactured Chemicals (2014) RFA Text | Recipients Lists
Research Category: Chemical Safety for Sustainability
Objective:
The overall objective of this project is to advance the adverse outcome pathway framework to predict effects of contaminants with different modes of action on the neurobehavior of larval fish from three different species and to determine what Adverse Outcome Pathways (AOPs) are common between species.
Objective 1: Identify genes predictive of neurobehavior toxicity in response to exposure to two different chemicals with different molecular initiating events and modes of action in order to identify neurobehavior AOPs using a reverse engineering approach on zebrafish
Objective 2: Determine the effects of PCB126 and MeHg on gene expression and behavior of the larval stage of two species of ecological relevance (fathead minnow and yellow perch).
Objective 3: Incorporate behavioral effects and transcriptomics data from fathead minnow and yellow perch into an individual-based model (IBM) to predict changes in growth and survival to complete the neurobehavior AOP suitable for ecological risk assessment for MeHg and PCB126.
Objective 4: Define and compare neurobehavioral AOPs between species and contaminants to determine their similarities and to elucidate what kind of information is lost or gained by using a typical laboratory model to inform on environmentally relevant species at the population level.
Progress Summary:
Objective 1 and Objective 2
We have completed exposures for both contaminants and videotaped behavioral assays for yellow perch and zebrafish. The fathead minnow behavioral assays are currently ongoing. The brains were isolated using our newly developed microdissection technique. The brains are going to be sent off for transcriptomic analysis once the fathead minnow assays are complete and the brains from fathead minnow larvae are isolated. We also sequenced the yellow perch genome, and have just completed one other approach to increase the number of reads. This is the first time the yellow perch transcriptome has been sequenced and it should add great value to many future studies that use yellow perch transcriptomics. The manuscript is in preparation. The behavior has been videotaped, and we are currently seeking a graduate student to analyze the videos. We anticipate analyzing the videos for swimming speed, resting time, prey choice, handling time, and capture success. The data from these behavioral assays will be linked to an individual-based model. We have completed brain dissections and behavioral video capture for zebrafish, yellow perch and preliminary data for killifish. At least 180 brains have been collected for zebrafish and yellow perch and 60 for killifish.
Species VMR Videos Locomotion Videos Feeding Videos
Zebrafish 36 (384) 180 (1,800) 278 (278)
Yellow Perch Not possible 122 (1,220) 326 (326)
Killifish 14 (168) 30 (300) 211 (211)
Video #’s shown; # of individuals in parentheses
Objective 3
We have already developed a yellow perch individual-based model (IBM; manuscript to be submitted within the next year) that examines the impacts of sublethal impacts of contaminants on the growth and survival of a yellow perch cohort. Developed in Fortran, this model tracks individuals of a cohort from hatch through the pelagic larval phase in two different habitats. However, the model lacked the generalizability required to utilize this IBM to explore a more diverse array of contaminants, environments and species. Therefore, we have taken a this model and made it more generalizable by removing much of the hard-wired coding structure, which prevented using the model for different environments or species, and replaced these with input files that can be developed for any species with adequate data. Input files follow the same format, that we have documented, making the model more user-friendly as well. As such, the IBM can easily change between species and environments (including numbers of predators and prey types included in the model). With this more generalized model, we are currently developing a fathead minnow IBM to explore the sublethal impacts of MeHg and PCB on larval fathead minnow growth and survival. This particular model will be more basic than the previously developed yellow perch IBM so as to facilitate 1) sensitivity and uncertainty analysis and 2) comparing model results among our focal species (killifish, yellow perch, fathead minnow). As such, we have collected fathead parameters to be used in the development of such a model with documentation. We will present the preliminary version of this model at Society for Environmental Toxicology and Chemistry in 2017. This model should be of interest to the EPA because of their work with fathead minnows as model organism for ecotoxicology research. In addition to IBMs developed in Fortran, we also developed a NetLogo version of the larval fish IBM for both killifish and yellow perch. It is hoped that this model, due to its user-friendly advantages over Fortran, could be a base model utilized for a variety of species and contaminants by users outside our immediate project team. We are exploring using our NetLogo version for larval killifish, yellow perch, fathead minnows and lake trout. Finally, we have also begun a sensitivity analyses of the generalized, simple IBM to determine parameter uncertainty. We will conduct sensitivity analyses with both simplified perch and fathead minnow parameters. To do so, we simplified the existing yellow perch IBM to minimize the number of parameters to include and enhance the feasibility to adequately assess the model. We are working on selecting the appropriate parameter distributions for each parameter included in the model. After this is completed, we will generate the required input files for the sensitivity analyses, run the sensitivity analysis, and determine to which parameters the model is most sensitive. This process will assist us in our future risk assessment analysis.
Other Progress
We have a Co-operative agreement with Dr. Diane Nacci’s group at the EPA in Narragansett RI. They have begun to conduct parallel experiments in killifish (see Table). We have been collaborating with Dr. Roger Nisbet and his co-investigators of an EPA STAR grant funded under the same RFP as this grant, through a National Institute of Mathematical and Biological Synthesis (NIMBioS) working group to bridge our adverse outcome pathway work to dynamic energy budgets. This has potential to be quite transformative because it will mean we can screen thousands of chemical to predict impacts on thousands of species.
Future Activities:
The perch transcriptome is sequenced and we plan to submit a manuscript in the near future. The fathead minnow model will be finished soon and we incorporate uncertainty into risk assessments. The behavioral assays have to be analyzed. Once behavior is analyzed, the RNA sequencing is complete, we can compare between species.
Journal Articles:
No journal articles submitted with this report: View all 26 publications for this projectSupplemental Keywords:
transcriptomics, larval fish, fathead minnow, yellow perch, zebrafish, neurobehavior, MeHg, PCBs, adverse outcome pathways, individual-based models, ecological risk assessment, uncertainty, riskProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.
Project Research Results
- Final Report
- 2019 Progress Report
- 2018 Progress Report
- 2017 Progress Report
- 2015 Progress Report
- Original Abstract
6 journal articles for this project