PW05 Genomics and Proteomics
Exhibit Hall
8:00 AM - Wednesday, 12 November 2003
(PW097) Toxicogenomics in Marine Systems.
Walsh, P1, Bookman, R1, Mayer, G1, Zaias, J1, Abraham, W1, Grosell, M1, Blanchard, J1, Crawford, D1, Bourdelais, A2, Baden, D2, 1 University of Miami, Miami, FL, USA2 University of North Carolina, Wilmington, NC, USA
ABSTRACT- The NIEHS Marine and Freshwater Biomedical Sciences Center at the University of Miami is taking two approaches to the emerging area of environmental toxicogenomics. First, commercial mouse arrays are being used to examine gene expression changes associated with exposures to marine algal toxins in mammals. As one example of this approach, the marine brevetoxins (PbTxs) are multi-cyclic polyether toxins produced by dinoflagelletes (e.g., Karenia brevis) that are responsible for fish kills and human respiratory symptoms associated with harmful algal blooms known as red tides. Although PbTxs are potent and acute activators of voltage-gated sodium channels, in prior work, we discovered that one isoform, PbTx-6, binds substantially to the aryl hydrocarbon receptor (AhR) with nearly equal avidity as classic dioxin ligands. Thus, there is potential for multiple pathway level responses through direct activation of gene transcription mediated by AhR. To test this hypothesis mice were dosed with sub-lethal levels of purified PbTx-6, and global mRNA expression patterns were assessed. Results will be presented demonstrating that PbTx elicits an acute phase response in mice. In a second approach, we are developing microarrays from non-model aquatic species (e.g., the common killifish, Fundulus heteroclitus) for parallel studies of marine toxins, as well as to examine gene expression changes associated with aquatic and dietary metal exposures. Thus this presentation will also report on our methods for array construction from non-model species, as well as preliminary data on PbTx and metals exposures in killifish. (Supported by NIEHS ES05705).
Key words: brevetoxins, Fundulus heteroclitus, harmful algal blooms, acute phase response