HA5 Genomics and Proteomics
Room 17A/B, Level 4
8:00 AM - 12:00 PM, Thursday, 13 November 2003
Chair: Ferguson, Lee ,
(521) Using genomics to examine multiple exposure variables in bioindicators research.
Miracle, A1, Lattier, D1, 1 National Exposure Research Laboratory, US EPA, Cincinnati, Ohio, USA
ABSTRACT- Genomics technologies provide a powerful tool for rapid assessment of differentially expressed genes in laboratory and field animals exposed to toxicants, and a means by which to link the earliest indicators of exposure to diverse effects in organisms and populations. However, application of these new technologies can be challenging when applied to an environmental model organism that has not been historically used in basic biological research. Because there is very little gene sequence information for the standard aquatic toxicology organism, the fathead minnow (Pimephales promelas), a unique approach was developed to examine specific gene expression in response to a potent estrogenic stressor across dose and age variables. Exposure-specific subtractive cDNA libraries were constructed from adult liver using 17 
- ethynylestradiol (EE2) at nominal, but environmentally relevant concentrations (5 ppt). The resulting differentially expressed cDNA clones were arrayed on a glass slide microarray platform for differences in individual variation, life stages, and chemical concentrations. Our data suggest that gene expression profiling will provide a sensitive measure of response to environmental estrogens when analyzed in context of various developmental stages and inter-individual variations. Thus, the use of genomics and microarray technologies to examine gene expression promises to be a powerful tool in understanding environmental exposures and subsequent impacts.
Key words: genomics, microarrays, cDNA libraries, estrogens