Use of gene regulatory sensors to monitor environmental pollutant levels in small mammals and birds

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The abundance of pesticides and dioxin-like pollutants has massively increased in the environment due to human activity. Some of these chemicals are persistent and accumulate in the food chain, which raises major concerns regarding mid- and long-term exposure on human and even wildlife health. The classical way of measuring such pollutants in the environment is to sample water and soil sources by biochemical means to assess their abundance. Once these measurements are determined, it is assessed whether they are within a range that is deemed "safe" for living creatures. However the major flaw with this is that how does one know how much of these chemicals are required to affect the health of individual species? Cells will be detoxified of pollutants and pesticides, at least in part, by the action of the aryl hydrocarbon receptor (AhR), which regulates xenobiotic metabolism enzymes belonging to the cytochrome P450 1A family (including CYP1A1 and CYP1B1). In theory, the more these CYP genes are expressed, the more a particular species is dealing with a significant dose of a particular pollutant. My laboratory has developed molecular tools to measure CYP gene expression in cells by qRT-PCR. Thus, my research plan will be to measure CYP1A1 and CYP1B1 gene expression in animals that live close to regions of intense agricultural practices, and also in regions where the use of pesticides is minimal. These species will include (but not limited to) the tree swallow, the masked shrew, the raccoon, and the little brown bat. We will also monitor if estrogen signaling is compromised in these animals and directly test for the presence of genotoxic estrogen metabolites. This multidisciplinary research program aims at addressing several important biological/environmental problems. I firmly believe that our genetic approach (coupled to HPLC/mass spectrometry) is significantly more sensitive and accurate than conventional biochemical/chemical methods to measure contamination in the environment. Hence our genetic tools could prove to be extremely useful and cost effective in assessing the potential effects of intense agriculture on wildlife and human health.