You are here:
Application of a long-established molecular marker in larval teleosts to evaluate estrogenic potential in surface waters and wastewater effluents
Citation:
REDDY, T. V., D. L. LATTIER, J. M. LAZORCHAK, D. A. GORDON, M. E. Smith, AND M. CRANE. Application of a long-established molecular marker in larval teleosts to evaluate estrogenic potential in surface waters and wastewater effluents. Presented at SETAC North America 32nd Annual Meeting, Boston, MA, November 13 - 17, 2011.
Impact/Purpose:
Experimental procedures accomplished with limited biomass (early lifestage) is a step toward future Agency compliance, and likely to be perceived as more palatable by those advocating for animal welfare and humane conduct in animal testing. In addition to considerable cost and time savings, elimination of animal necropsy is a welcome facet of this protocol. Principally, this approach provides a straightforward, economical and transferable monitoring routine for surface waters and wastewater effluents.
Description:
In recent years molecular indicators, diagnostic for exposure in aquatic systems, have been developed using teleostean models in laboratory and field settings. Our laboratory has previously shown that the gene for vitellogenin, a protein precursor of egg yolk in oviparous animals, can undergo induced expression in fathead minnow (FHM; Pimephales promelas) swim-up fry. FHM are widely distributed freshwater fish, a key organism among USEPA standard aquatic toxicology models. Measurement of vitellogenin gene (Vtg) transcription as an approach to characterize presence of estrogen active compounds in early life stage development was applied to FHM 48 hr post hatch and in situ embryos exposed to control (0), 0.625, l.25, 2.5 and 5.0 ng L-1 of the synthetic estrogen, 17a-ethynylestradiol (EE2). Following post exposure, total RNA was isolated from single larvae in addition to statistically requisite numbers of groups comprising pooled larvae in quantities of 5 and 10. Using synthetic oligonucleotide primers specific for P. promelas VtgI primary transcript, quantified RNA was thermally amplified by QPCR. Initial analysis of ongoing experiments suggests that use of early life stages as biologic indicators for estrogenic EDCs offers an efficient and viable approach.