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Precision Omics for Aquatic wildlife health assessment

PRecision Omics for AQUAtic wildlife health assessment

Aquatic wildlife act as sentinels for environmental and human health. They are apt indicators of pollutant and climate change effects yet the current methods do not effectively capture the scope of deleterious effects that impact the individual and populations. Particularly vulnerable are those life stages where considerable growth, formation, and remodeling of body plans occur such as in embryonic/fetal development, metamorphosis, infancy, and childhood. Exposure at any of these critical stages could result in permanent dysfunction, increased susceptibility to cancer, behavioural and/or reproductive problems. Sometimes these effects can span multiple generations. It is critical to have the appropriate tools to identify when a deleterious outcome is likely to happen to effectively mitigate problems. We can do this by looking at genes that are expressed and the products that they make.

The Helbing lab is developing and using a wide range of molecular approaches on amphibians, fish, marine mammals, bivalves, and other wildlife to better define effects of exposure to substances including pharmaceuticals, personal care products, oil spills, and chemical mixtures from municipal wastewater. To assess animal health, we are enabling the application of the latest 'omics technologies to wildlife species including RNA-Seq, quantitative real time polymerase chain reaction (qPCR), metabolomics and proteomics. We have even sequenced and assembled the first “true frog” genome! One research goal is to develop accessible non-lethal health tests for wildlife. To assess population health, we are applying our molecular expertise to develop robust tools for biologists to track species distribution using environmental DNA. These eDNA tools can be made to test for endangered or invasive species depending upon the need, and the presence of their DNA can be tested from a scoop of water!

Cellular mechanisms of amphibian metamorphosis

Frog tadpoles undergo remarkable remodeling of the body plan in anticipation of the transition from an aquatic to a terrestrial lifestyle. This metamorphosis is caused by thyroid hormones - the same hormones that are important in all vertebrates for normal growth, development, and health. These hormones have very different effects depending upon the tissue type. In tadpoles, the tail disappears, the legs grow, the skin changes, and the liver and brain remodel - all in response to thyroid hormones. This research program focuses on understanding how these differences come about. We hypothesize that there are specific genes that contribute to these differences and we are identifying them and examining the molecular switches that regulate how they work. Understanding this is important because it gives us fundamental information on different tissue responses that can be used to better design therapeutics used as hormone replacements. It also gives us insight into why some tissues are more sensitive to environmental contaminants that act as hormone disruptors. These endocrine disruptors come from a variety of sources such as plants, pharmaceuticals, pesticides, personal care products, and industry. A better understanding and identification of thyroid hormone disruptors will help develop effective means of keeping track of their release into the environment and contribute to creating safer consumer products.

To accomplish these goals, we are using powerful biochemical and bioinformatics techniques to examine gene expression programs and their controlling factors in tadpole tissues. Since thyroid hormone signaling is important in all vertebrates including humans, the knowledge obtained by studying them will give us important clues in understanding the basis of diseases including cancer and metabolic disorders.

Adult male bullfrog, Rana catesbiana

Last Update: April 2018