PARENT SESSION
MP6 - Transgenic Organisms as Environmental Biosensors
Chair: Jackson, David1, 1 568 Doughten Drive, Ft. Detrick, MD, USA
Co-chair: van der Schalie, William2, 2 568 Doughten Drive, Ft. Detrick, MD
2:10 PM to 5:30 PM - Monday, 18 November 2002
Room Ballroom B
(295) Developmental toxicology in living zebrafish embryos carrying a stably integrated hsp70/eGFP reporter gene.
Blechinger, Scott*,1, Salisbury, Heather1, Warren, James2, Kuwada, John3, Krone, Patrick1, 1 University of Saskatchewan, Saskatoon, Saskatchewan, Canada2 Penn State University, Erie, PA, USA3 University of Michigan, Ann Arbor, MI, USA
ABSTRACT- The toxic effects of cadmium and other heavy metals have been well established, and many of these and other environmental pollutants are known to be embryotoxic or teratogenic. However, it has proven difficult to identify individual cells that respond to toxicants among the wide range of cell populations in an intact animal, particularly during early development when cells are continually changing their molecular and physiological characteristics as they differentiate. Here we report the establishment of an in vivo system that utilizes hsp70 gene activation as a measure of cadmium and arsenic toxicity in living early larvae of transgenic zebrafish carrying a stably integrated hsp70/eGFP reporter gene. We demonstrate that eGFP expression in this strain of fish acts as an accurate and reproducible indicator of cell-specific induction of the endogenous hsp70 gene and that it is expressed in predicted target tissues following cadmium and arsenic exposure. Furthermore, the transgene responds in a dose-dependent manner at concentrations similar to those observed for morphological indicators of early life stage toxicity, and is sensitive enough to detect cadmium and arsenic toxicity at doses below EC50 and LC50 values. The stable nature of this transgenic line should allow for rapid and reproducible toxicological profiling in live embryos and larvae as well as monitoring of subsequent morphilogical and physiological impacts following transgene induction in the same individual animal.
Key words: hsp70/eGFP, cadmium, arsenic, zebrafish